September 2004
                          NSF04/16/EPADWCTR
                            EPA/600/R-04/186
Environmental Technology
Verification Report

Removal of Arsenic in Drinking Water

Watts Premier
M-Series M-15,000 Reverse
Osmosis Treatment System
            Prepared by
          NSF International
       Under a Cooperative Agreement with
      U.S. Environmental Protection Agency

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         THE ENVIRONMENTAL TECHNOLOGY VERIFICATION
                                     PROGRAM
                                   ET
      >O
v
    U.S. Environmental Protection Agency                                               NSF International
                     ETV Joint Verification Statement
    TECHNOLOGY TYPE:  MEMBRANE FILTRATION USED IN DRINKING WATER
                           TREATMENT SYSTEMS
    APPLICATION:         REMOVAL OF ARSENIC
    TECHNOLOGY NAME:  WATTS PREMIER M-SERIES M-15,000 REVERSE
                           OSMOSIS (RO) TREATMENT SYSTEM

    COMPANY:            WATTS PREMIER

    ADDRESS:             1725 W. WILLIAMS DRIVE, #C-20 PHONE:  (623)505-1514
                           PHOENIX, ARIZONA 85027       FAX:     (623)931-0191

    WEB SITE:             www.wattspremier.com
    EMAIL:                murphysp@wattsind.com
The U.S. Environmental Protection Agency (EPA) supports the Environmental Technology Verification
(ETV)  Program to facilitate  the deployment of innovative  or improved environmental technologies
through performance verification and dissemination of information.  The goal of the ETV Program is to
further  environmental protection by accelerating the acceptance and use of improved and more cost-
effective technologies. ETV seeks to achieve this goal by providing high-quality, peer-reviewed data on
technology performance to those involved in the design,  distribution, permitting, purchase, and use of
environmental technologies.

ETV works in partnership with recognized standards and testing organizations, stakeholder groups
(consisting of buyers, vendor organizations, and permitters), and with the full participation of individual
technology developers. The program evaluates the performance of innovative technologies by developing
test plans that are responsive to the needs of stakeholders, conducting field or laboratory tests  (as
appropriate), collecting and analyzing data,  and preparing peer-reviewed reports. All evaluations  are
conducted in accordance with rigorous  quality  assurance protocols to ensure that data of known and
adequate quality are generated and that the results are defensible.

NSF International (NSF) in cooperation with the EPA operates the Drinking Water Systems (DWS)
Center, one of seven technology areas under the ETV Program.  The DWS Center recently evaluated the
performance  of a membrane  separations system for the  reduction  of arsenic in drinking water. This
verification statement provides a summary of the test results  for the Watts Premier MSeries Ml5,000
Reverse Osmosis (RO) Treatment System. MWH, an NSF-qualified field testing organization (FTO),
performed the verification testing. The verification report contains a comprehensive description of the
test.
04/16/EPADWCTR     The accompanying notice is an integral part of this verification statement.        September 2004
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ABSTRACT
Verification testing of the Watts Premier M-Series M-15,000 RO Treatment System was conducted over a
31-day period from April 26, 2004, through May 26, 2004.  This test was conducted at the Coachella
Valley Water District (CVWD) Well 7802 in Thermal,  California.  The source water  was a chlorinated
groundwater supply.  Based on the manufacturer's recommendations, the unit was operated at an average
inlet pressure of 135  pounds per square inch (psi), water recovery of 53%, flux of 34 gallons per square-
foot per day (gfd), and a specific flux of approximately 0.36 gfd/psi at 25 degrees Celsius (°C). The total
arsenic (As) concentration in the feed water averaged 14 micrograms per liter (ug/L)  during the testing
period.  The M-15,000 RO Treatment System reduced the arsenic levels to below detection (1.0 ug/L) for
all but the last two samples, which were 1.4 and 1.2 ug/L.  Six sets of samples were speciated and the
dominant form of arsenic was As(V).

The system operated for 27 days of the 31-day verification period, with three system shut downs due to
operational issues associated with the pre-filter.  The  verification study indicated that arsenic can be
removed by the  M-15,000 RO  Treatment System, but depending on the source water characteristics, the
appropriate pre-filter selection is important to prevent clogging of the pre-filters.

TECHNOLOGY DESCRIPTION
The following technology description was provided by the manufacturer and has not been verified.

The M-15,000 RO Treatment  System contains six  pressure  vessels, each  containing  one 4" x 40"
membrane  module.  Each  stainless steel  pressure vessel  is four inches (10  cm) in diameter and
approximately 45 inches (110 cm) long. The M-15,000 RO Treatment System is a skid-mounted unit that
is constructed with a carbon steel frame and  powder coating.  The verification unit is 37 %" (length) x 28
%" (depth) x 53 1A>"  (height) and requires a minimum  of 18" clearance on all sides for  servicing, 40"
clearance on top, and a floor sink drain of  1 1A" diameter within  10' of the processing unit.  The main
components of the RO unit are a 3 Hp feed pump, carbon bloc (for removal of chlorine) or sediment pre-
filter pretreatment, six pressure vessels, and  an in-line conductivity meter. The  M-15,000 RO Treatment
System unit may use either a  carbon pretreatment for  removal of chlorine or a sediment pre-filter as
standard equipment for the system.  The membranes are not tolerant of chlorine and, therefore, when the
system is used on a chlorinated water source, the carbon  pretreatment should be used.

VERIFICATION TESTING DESCRIPTION
Test Site
The verification testing site was the CVWD Well 7802 located in Thermal, California. The feed water for
the verification study was a chlorinated source, with an  average free chlorine residual of 0.47 milligrams
per liter (mg/L).  The chlorine enters the distribution system at the discharge manifold, and was fed from
a Hammond's tablet feeder using calcium hypochlorite  tablets as  the chlorine source. The average feed
water quality during the verification testing is provided in the table below.

In addition to being a suitable fit for water quality, the site also had sufficient access (1  acre site); full
electrical supply with backup  diesel powered generator; 6' privacy/security wall; all utilities readily
available including raw water supply, power, and a drain (blow-off structure)  for the discharge of the
water from the  ETV verification  testing;  and  safety  facilities,  including an  emergency  shower and
eyewash.
04/16/EPADWCTR      The accompanying notice is an integral part of this verification statement.         September 2004
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Total Arsenic
Dissolved Arsenic
As (III)
As(V)1
TOC
Calcium
Chloride
Hardness
Alkalinity
Free Chlorine
Total Chlorine
pH2
Temperature
Mg/L
Mg/L
Mg/L
Mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
--
°C
27
5
5
5
5
5
5
5
5
18
18
27
54
14
14
3.7
11
<0.50
4.8
8.5
18
83
0.47
0.51
9.213
27.5
Turbidity
Conductivity
TDS
TSS
Manganese
Iron
Barium
Silica
Fluoride
Sulfate
Chromium
Vanadium

NTU3
umoh/cm
mg/L
mg/L
Mg/L
mg/L
Mg/L
mg/L
mg/L
mg/L
Mg/L
Mg/L

5
54
27
5
5
5
5
5
5
5
5
5

0.40
231
140
<10
<2.0
0.019
7.1
15
0.80
20
13
49

Average Feed Water Quality during Verification Testing
                            #of
   Parameter       Units   Samples    Average     Parameter
                                           Units
  #of
Samples
Average
1 As (V) is a calculated value.
3 pH is reported as the median, not the average.
3 Nephelometric Turbidity Unit(s).

Methods and Procedures

Water  quality was  monitored from  three water  streams:   feed water,  permeate, and  concentrate.
Conductivity,  pH, turbidity, chlorine  (free  and total), temperature, alkalinity, hardness analyses were
conducted on-site, using equipment set up in the pump house at CVWD Well 7802 and in accordance
with Standard Methods for the Examination of Water and Wastewater, 2Cfh edition.  Conductivity and
feed water temperature were monitored twice per day, while pH was monitored once per day.  Alkalinity,
hardness, chlorine, and turbidity were monitored once per week on-site using methods approved by NSF.
The following additional samples were sent to MWH Laboratories for analysis: arsenic (total, dissolved,
and As+3), total suspended solids (TSS), total dissolved solids (TDS), total organic carbon (TOC), silica,
barium, calcium, chloride, sulfate, iron, manganese, fluoride, chromium, and  vanadium.  Total arsenic
and TDS samples were collected once per day; dissolved arsenic, As+3, TSS, TDS, TOC, silica, barium,
calcium, chloride, sulfate,  iron, manganese, fluoride,  chromium, and vanadium samples were collected
once per week. One sample was collected during the verification test for silt density index (SDI) analysis.
Complete descriptions of the verification testing results and quality assurance/quality control procedures
are included in the verification report.

VERIFICATION OF PERFORMANCE
System Operation
RO is a pressure-driven process, with the pressure  used for separation by allowing fresh water to move
through a membrane, leaving various  dissolved constituents of the water behind.  In the M-l5,000 RO
Treatment System, feed water  is initially passed through a pre-filter (sediment filter or  carbon bloc for
chlorine removal) to remove particles that have the potential to damage the membrane.  There is a
sampling port just prior to  the pre-filter to collect the feed water samples. After passing through the pre-
filter, the feed water is blended with re-circulated concentrate water and is then referred to as the inlet
water.  The inlet water is  then sent through a booster pump and after leaving the discharge side of the
pump,  the water line is split and feeds the two separate  banks of membranes (six membranes in total),
starting with membrane 1  and 4. For  the first bank of membranes, concentrate from membrane 1 feeds
membrane 2 and concentrate from membrane 2 feeds membrane 3.  For the second bank of membranes,
concentrate from membrane 4 feeds membrane 5 and concentrate from membrane 5 feeds membrane 6.
04/16/EPADWCTR
The accompanying notice is an integral part of this verification statement.
                         VS-iii
           September 2004

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Permeate from all membranes is collected from the bottom of the housing and exits the unit as drinking
water.  There is a permeate sample port for each of the six membranes, as well as the blended permeate
from all six of the membranes. During the verification test, permeate samples were collected from the
blended permeate sample port. Concentrate from membranes 3 and 6 is split, some being purged to waste
and some re-circulating back to the head of the system, just after the pre-filter where it is blended with the
feed water to create the inlet water. The concentrate that is re-circulated back to the head of the system is
referred to as recycle water.

The M-15,000 RO Treatment System was set up in accordance with the manufacturer's recommendations
the week prior to the verification test. The unit was tested to make sure all systems were operating in
accordance  with  their  recommended  ranges.   Based  on  discussions between the  FTO and the
manufacturer, the set points were adjusted to achieve a 50% permeate recovery. Once the set points were
adjusted, the system flow rates were stable for the remainder of the verification period.  The feed water
pressure was stable throughout the testing period, however, the inlet pressure varied from 102 to 145 psi,
due to clogging of the carbon bloc pre-filter.  Once the pre-filter was replaced with a sediment filter, the
inlet pressures stabilized (140 to 150 psi) for the remainder of the verification testing.

Water Quality Results
The M-15,000 RO Treatment System removed the feed water total arsenic from 14 ug/L (on average) to
non-detectable levels (<1.0 ug/L) for all but the last two samples collected, which were 1.4 and 1.2 ug/L.
As shown in the figure below, the  unit was able to produce a consistent, high quality permeate with total
arsenic levels below 1.0 ug/L in 95% of the  samples over the range of feed water of 12 to 16 ug/L.
Throughout most of the verification test, the total arsenic mass balance was very close, with the exception
of April 29, 2004, and  May 10, 2004, where the arsenic concentration in  the concentrate  stream was
significantly higher (greater than the 95% confidence interval), at 84 ug/L and 38 ug/L respectively. The
permeate conductivity and TDS slowly increased  throughout the verification testing, starting around 6.4
umoh/cm and increasing to 76.6 umoh/cm for conductivity and starting at <10  mg/L and increasing to 45
mg/L for TDS.  During the verification testing, a total of five weekly samples were collected for inorganic
analyses. Based on these five samples, the M-15,000 RO Treatment System removed on average: >72%
barium, >79% calcium,  85% fluoride, 85% chloride, >92% chromium, >90% sulfate,  >93% vanadium,
38% iron, and 62% silica.  Manganese was also sampled and analyzed during the verification testing, but
the percent removal could not be determined due to non-detectable (<2 ug/L) levels for all of the feed
water and permeate samples.
04/16/EPADWCTR      The accompanying notice is an integral part of this verification statement.        September 2004
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                                                                             -n— Concentrate
                                                                              •  Feed Water
                                                                             -O— Permeate
                               Verificatin Testing Date

                           Temporal Plot of Total Arsenic

Operation and Maintenance Results
The system ran continuously for 27 of the 31-day verification testing period.  For one 4-day period, the
system was shut down due to operational issues. Clogging of the carbon bloc pre-filter is believed to be
the cause of the shut down. The unit automatically shut down on two separate occasions, also believed to
be related to  clogging of the carbon bloc pre-filter.  On May  13, 2004 the carbon bloc pre-filter was
replaced with a 20-micron  sediment pre-filter.  The system ran continuously after the sediment filter was
installed, until the end of the verification testing on May 26,  2004, when the system was manually shut
down.

Quarterly maintenance was conducted upon completion of the verification testing.  The maintenance
procedure took approximately 45 minutes to change out the O-rings on the pre-filter and brine line,  and
replace the pre-filter and two of the six RO membranes. Upon completion of the maintenance procedures,
the system was started back up and both water quality and operational conditions were recorded. The
specific flux immediately  prior to the maintenance was 0.34  gfd/psi and upon start up after the
maintenance was 0.33 gfd/psi, thus a 97% recovery of specific flux was achieved upon completion of the
maintenance procedures.
04/16/EPADWCTR
The accompanying notice is an integral part of this verification statement.
                         VS-v
September 2004

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Consumables and Waste Generation

There were no "consumable" chemical items used for the verification testing; however, the pre-filter to
the system would be a consumable product and would have to be disposed of as solid waste.  The
concentrate waste stream produced from the verification test was blended back with the permeate water
for an equivalent water quality to the feed water from the CVWD Well 7802.  This water was then sent to
a blow-off structure for disposal. The estimated concentrate production rate was 17,300 gallons per day,
based on the targeted 50% permeate recovery.

Quality Assurance/Quality Control
NSF provided technical and quality assurance  oversight of the verification testing as described in the
verification report, including an audit of nearly 100% of the data. NSF personnel also conducted a
technical systems audit during testing to ensure the testing was in compliance with the test plan.  A
complete description of the QA/QC procedures is provided in the verification report.
      Original Signed by
      Lawrence W. Reiter
                09/30/04
Original Signed by
Gordon Bellen
09/30/04
   Lawrence W. Reiter                Date
   Acting Director
   National Risk Management Research Laboratory
   Office of Research and Development
   United States Environmental Protection Agency
                                     Gordon Bellen
                                     Vice President
                                     Research
                                     NSF International
                        Date
    NOTICE:  Verifications are based on an evaluation of technology performance under specific,
    predetermined criteria and the appropriate quality assurance procedures.  EPA and NSF make no
    expressed or implied warranties as to the performance of the technology and do not certify that a
    technology will always operate as verified.  The end-user is solely responsible for complying with
    any and all applicable federal, state, and local requirements.  Mention of corporate names, trade
    names, or commercial products does not constitute  endorsement or recommendation for use of
    specific products.  This  report is not an NSF Certification  of the specific product mentioned
    herein.
       Availability of Supporting Documents
       Copies  of the ETV Protocol for Equipment Verification  Testing for Arsenic Removal
       dated September 2003, the ETV Protocol for Equipment Verification Testing for Removal
       of Inorganic Constituents  dated  April  2002,  the verification   statement,  and  the
       verification report (NSF Report # 04/16/EPADWCTR) are available from the following
       sources:
       (NOTE: Appendices are not included in the verification report.  Appendices are available
       from NSF upon request.)
       1.  ETV Drinking Water Systems Center Manager (order hard copy)
           NSF International
           P.O. Box 130140
           Ann Arbor, Michigan 48113-0140
       2.  NSF web site: http://www.nsf. org/etv (electronic copy)
       3.  EPA web site: http://www. epa.gov/etv (electronic copy)
04/16/EPADWCTR
The accompanying notice is an integral part of this verification statement.        September 2004
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                                                      September 2004
     Environmental Technology Verification Report
         Removal of Arsenic in Drinking Water

                 Watts Premier M-Series
      M-15,000 Reverse Osmosis Treatment System
                         Prepared for:

                       NSF International
                   Ann Arbor, Michigan 48105
                         Prepared by:

                           MWH
                      Pasadena, CA 91101
Under a cooperative agreement with the U.S. Environmental Protection Agency
                 Jeffrey Q. Adams, Project Officer
           National Risk Management Research Laboratory
               U.S. Environmental Protection Agency
                     Cincinnati, Ohio 45268

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                                       Notice

The  U.S.  Environmental Protection  Agency  (EPA), through its  Office  of Research and
Development, has financially supported and collaborated with NSF International (NSF) under
Cooperative Agreement No. R-82833301. This verification effort was supported by the Drinking
Water  Systems  (DWS) Center,  operating  under the  Environmental  Technology Verification
(ETV)  Program. This  document has been peer reviewed,  reviewed  by NSF and EPA, and
recommended for public release.

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                                       Foreword

       The  U.S. Environmental  Protection  Agency (EPA)  is  charged by  Congress  with
protecting  the  Nation's  land,  air,  and water  resources.  Under  a  mandate  of  national
environmental laws, the  Agency  strives to  formulate  and  implement  actions leading  to a
compatible balance  between human activities  and the ability of natural  systems to support and
nurture  life. To  meet this mandate, EPA's research program is providing data and technical
support for solving environmental  problems today  and building a  science knowledge  base
necessary to manage our ecological  resources  wisely,  understand how  pollutants affect our
health, and prevent or reduce environmental risks in the future.

       The National Risk Management Research Laboratory (NRMRL) is the  Agency's center
for investigation of technological and management approaches for preventing and reducing risks
from pollution that  threaten human health and the environment. The focus of the Laboratory's
research program is on  methods and their cost-effectiveness  for prevention and control of
pollution to air, land, water, and subsurface resources; protection of water quality in public water
systems; remediation of contaminated  sites, sediments and ground water; prevention and control
of indoor air pollution; and restoration of ecosystems.  NRMRL collaborates with both public
and private sector partners to foster technologies that reduce the cost of compliance and to
anticipate emerging problems. NRMRL's research provides solutions to environmental problems
by: developing and promoting technologies that protect and improve the environment; advancing
scientific and engineering information to support regulatory and policy decisions; and providing
the technical support and information  transfer to  ensure implementation of environmental
regulations and strategies at the national, state, and community levels.

       This publication  has been produced  as part of the  Laboratory's strategic long-term
research plan. It is published and made available by EPA's Office of Research and Development
to assist the user community and to link researchers with their clients.
                                         Lawrence W. Reiter, Acting Director
                                         National Risk Management Research Laboratory
                                           in

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                                   Table of Contents

Section                                                                            Page
Verification Statement	VS-i
Title Page	i
Notice	ii
Foreword	iii
Table of Contents	iv
Abbreviations and Acronyms	ix
Acknowledgements	x

Chapter 1    Introduction  	1
1.1    ETV Purpose and Program Operation	1
1.2    Testing Participants and Responsibilities	1
       1.2.1  NSF International	2
       1.2.2  Field Testing Organization	2
       1.2.3  Manufacturer	3
       1.2.4  Analytical Laboratory	3
       1.2.5  U.S. Environmental Protection Agency	4
1.3    Verification Testing Site	4
       1.3.1  Source Water	4
       1.3.2  Pilot Effluent Discharge	5
       1.3.3  Discharge Permits	5

Chapter 2    Equipment Description and Operating Processes	6
2.1    Equipment  Description	6
2.2    Operating Process	10

Chapter 3    Methods and Procedures	13
3.1    Quantitative and Qualitative Evaluation Criteria	13
3.2    Key Treated Water Quality Parameters 	13
       3.2.1 Key Groundwater Quality Parameters the Equipment is Designed to Address	13
       3.2.2 Key Treated Water Quality Parameters for Evaluating Equipment Performance ...14
3.3    Calculations	14
       3.3.1  Calculation of Statistical  Uncertainty	14
       3.3.2  Calculation and Definition of Operational Parameters	15
3.4    Testing Schedule	19
3.5    Operation and Maintenance	20
3.6    Field Operations Procedures	20
3.7    Environmental Technology Verification Testing Plan	20
       3.7.1  Task 1:  Membrane Operation	21
       3.7.2  Task 2:  Cleaning Efficiency	21
       3.7.3  Task 3:  Feed Water and Treated Water Quality Monitoring	21
       3.7.4  Task 4:  Data Handling Protocol	22
       3.7.5  Task 5:  Quality Assurance Project Plan (QAPP)	22
3.8    Task 1: Membrane Optimization	22
                                           iv

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                              Table of Contents (continued)

Section                                                                             Page
       3.8.1   Experimental Objectives	23
       3.8.2   Work Plan	23
       3.8.3   Analytical Schedule	24
       3.8.4   Evaluation Criteria and Minimum Reporting Criteria	24
3.9    Task 2: Cleaning Efficiency	25
       3.9.1   Experimental Objectives	25
       3.9.2   Work Plan	25
       3.9.3   Analytical Schedule	26
       3.9.4   Evaluation Criteria and Minimum Reporting Criteria	26
3.10   Task 3: Water Quality Monitoring	27
       3.10.1  Experimental Objectives	27
       3.10.2  Work Plan	28
       3.10.3  Analytical Schedule	28
       3.10.4  Evaluation Criteria And Minimum Reporting Criteria	29
3.11   Task 4: Data Handling Protocol	29
       3.11.1  Experimental Objectives	30
       3.11.2  Work Plan	30
3.12   Task 5: Quality Assurance Project Plan (QAPP)	31
       3.12.1  Experimental Objectives	31
       3.12.2  Work Plan	31
       3.12.3  Monthly QA/QC Verification	31
       3.12.4  Data Correctness	31
              3.12.4.1 Representativeness	32
              3.12.4.2 Statistical Uncertainty	36
              3.12.4.3 Methodology for Measurement of Precision and Accuracy	37
              3.12.4.4 Completeness	41
       3.12.5  Calculation of Indictors of Data Quality	41
       3.12.6  Corrective Action Plan	42
3.13   Operation And Maintenance	43
       3.13.1  Operation	43
       3.13.2  Maintenance	44
       3.13.3  Operability	45

Chapter 4 Results and Discussion                                                      46
4.1    Introduction	46
4.2    Task 1: Membrane Operation	46
       4.2.1 General Operational Performance	41
              4.2.1.1  Feed Water, Permeate, Concentrate, and Recycle Flow Rates	47
              4.2.1.2  Membrane Element Inlet and Feed Water Pressures	50
              4.2.1.3  Water Recovery and Recycle Ratio	53
              4.2.1.4  Feed Water Temperature	55
              4.2.1.5  Flux, Specific Flux, Net Driving Pressure, and Osmotic Pressure	56

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                                Table of Contents (continued)

Section                                                                           Page
4.2.2  Power Consumption	62
       4.2.3 Consumables and Waste Generation	63
4.3 Task 2:  Cleaning Efficiency	63
       4.3.1  Measurement of Membrane Performance - Post Quarterly O&M Procedures	65
       4.3.2  Review of Watts Premier Operation and Maintenance Manual	67
4.4 Task 3:  Feed Water And Treated Water Quality Monitoring	67
       4.4.1 Percent Removal Of Inorganic Chemical Constituents	75
       4.4.2 Percent Removal Of Organic Constituents	80
             4.4.2.1 Mass Balance for Total Arsenic	81
             4.4.2.2 Limiting Salt Concentrations	82
       4.4.3  Removal of TSS	83
       4.4.4  SDI	84
       4.4.5  LSI	84
4.5 Task 4: Data Handling Protocol	83
4.6 Task 5:  Quality Assurance/Quality Control Results	83
       4.6.1 Precision	83
       4.6.2 Accuracy	88
       4.6.3 Off-Site Analysis of Samples	90
             4.6.3.1 Inorganic Samples	95
             4.6.3.2 Organic Samples	95
       4.6.4 Completeness	90
       4.6.5 NSF Field Inspection	90

Chapter 5    References	97

Chapter 6    Vendor Comments	98

Table
Table 1-1: Average Feed Water Quality during Verification Testing	 4
Table 2-1: Membrane Plant Design Criteria Reporting Items	9
Table 2-2: Membrane Element Characteristics	9
Table 2-3: Watts Premier M-l 5,000 RO Treatment System Specifications	11
Table 3-1: Quantitative and Qualitative Evaluation Criteria	13
Table 3-2: Operating Range of Watts Premier RO Membrane	14
Table 3-3: Key Treated Water Quality Parameters	14
Table 3-4: Equipment Operational Characteristics to be Evaluated in Each Task	22
Table 3-5: Frequency and Type of Operating Data	24
Table 3-6: Sampling Schedule and Methods for Feed, Permeate, & Concentrate Water	27
Table 3-7: Methodology for Measurement of Precision and Accuracy	37
Table 3-8: Laboratory Water Quality Indicators	39
Table 3-9: On-Site Water Quality Analysis Indicators	40
Table 3-10: Methodology for Use of Method Blanks	40
Table 3-11: Completeness Objectives Based on Sample Frequency	41
                                          VI

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                             Table of Contents (continued)
Table
                                                                                   Page
Table 3-12:  Corrective Action Plan [[[ 43
Table 4-1: Feed Water, Permeate, Concentrate and Recycle Flow Rates ..................................... 49
Table 4-2: Feed Water, Inlet, Back Pressure, and Tank Pressures ............................................... 52
Table 4-3: Water Recovery and Recycle Ratio [[[ 54
Table 4-4: Feed Water Temperature [[[ 55
Table 4-5: Daily Flux Data [[[ 57
Table 4-6: Daily Specific Flux Data at 25°C [[[ 58
Table 4-7: Osmotic Pressure Gradient [[[ 60
Table 4-8: Net Driving Pressure [[[ 62
Table 4-9: Power Totalizer for M-l 5,000 RO Treatment System ................................................ 63
Table 4-10:  Pre-and Post-Maintenance Specific Flux Recoveries ............................................... 66
Table 4-11:  Maintenance Efficiency Indicators [[[ 66
Table 4-12:  Pre and Post O&M Feed Water, Permeate, and Concentrate Water Quality ............ 67
Table 4-13:  Daily Feed Water, Concentrate, Permeate, and Total Arsenic Data ......................... 69
Table 4-14:  Daily Feed Water, Concentrate, Permeate, and TDS ................................................ 71
Table 4- 15   Daily pH Analysis [[[ 72
Table 4-16:  Daily Conductivity Analysis [[[ 73
Table 4-17:  On-site Weekly Water Quality Monitoring [[[ 74
Table 4-18:  On-site Free and Total Chlorine Monitoring [[[ 75
Table 4-19:  Weekly Speciated Arsenic Analyses [[[ 76
Table 4-20:  Weekly Analytical Parameters and Percent Removal ............................................... 77
Table 4-21:  Percent Removal of Organic Constituents  [[[ 80
Table 4-22:  Daily Total Arsenic Mass Balance [[[ 82
Table 4-23:  Solubility Products of Limiting Salt Concentrations ................................................ 83
Table 4-24:  Removal of Total Suspended Solids [[[ 84
Table4-25:  LSI Calculations (April 26, 2004) [[[ 85
Table 4-26:  Weekly Off-site Analytical Precision [[[ 87
Table 4-27:  On-site Analytical Precision [[[ 88

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                             Table of Contents (continued)

Figure                                                                            Page
Figure 4-4: Temporal plot of flux verses time	56
Figure 4-5: Specific flux at 25°C verses time	58
Figure 4-6: Osmotic pressure gradient verses time	59
Figure 4-7: Temporal profile of net driving pressure	61
Figure 4-8: Temporal plot of total arsenic	68
Figure 4-9: Temporal plot of TDS	70
Figure 4-10: Temporal plot of silica	78
Figure 4-11: Temporal plot of fluoride	78
Figure 4-12: Temporal plot of iron	79
Figure 4-13: Temporal plot of chloride	79
Figure 4-14: Temporal plot of sulfate	80
Figure 4-15: Daily total arsenic mass balance	81

Photograph                                                                        Page
Photograph 1:  Permeate and Concentrate Discharge Lines	5
Photograph 2:  Watts Premier M-15,000 RO Treatment System at CVWD Well 7802	8
Photograph 3:  Pre-Filter to Watts Premier M-15,000 RO Treatment System	10
Photograph 4:  Watts Premier M-15,000 RO Treatment System Pre-filters	64
Photograph 5:  Membrane RO Number 6 - Post Verification Testing	65

Appendices
Appendix A: Watts Premier M-Series M-15,000 RO Treatment System O&M Manual
Appendix B: On-Site Arsenic  Speciation Procedures
Appendix C: On-Site Logbook
Appendix D: Analytical Data from MWH Laboratories
Appendix E: Analytical Data and Procedures from SDI Analysis
                                          Vlll

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                               Abbreviations and Acronyms

AM          morning
As            arsenic
As (III)       arsenite
As (V)        arsenate
ASTM        American Society of Testing and Materials
°C            degree Celsius
CVWD       Coachella Valley Water District
°F            degree Fahrenheit
EPA          Environmental Protection Agency
ETV          environmental technology verification
Ft            feet
FTO          field testing organization
gfd           gallons per square-foot per day
gfd/psi        gallons per square-foot per day per pounds per square inch
gpd           gallons per day
gpm          gallon per minute
LCS          laboratory control sample
LFM          laboratory fortified matrix
LSI           Langelier Saturation Index
MB           method blank
mL           milliliter
mg/L          milligram
MRL          minimum reporting limit
NDP          net driving pressure
NELAC       National Environmental Laboratory Accreditation Conference
NIST          National Institute of Standards and Technology
NRMRL      National Risk Management Research Laboratory
NSF          NSF International (formerly known as the National Sanitation Foundation)
NTU          nephelometric turbidity unit(s)
O&M         operation and maintenance
p             pressure
PM           evening
psi           pounds per square inch
psig          gauge pressure
PSTP          Product Specific Test Plan
Q            flow rate
QAPP        Quality Assurance Project Plan
RO           reverse osmosis
RPD          Relative percent difference
SDI          silt density index
T            temperature
TDS          total dissolved solids
TOC          total  organic carbon
TSS          total suspended  solids
ug            microgram
                                            IX

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                                   Acknowledgments

The  field testing organization (FTO), MWH, was responsible for all elements in the testing
sequence, including  collection  of samples,  calibration  and verification  of instruments, data
collection and analysis, data management, data interpretation, and the preparation of this report.

       MWH
       300 N. Lake Ave, Suite 1200
       Pasadena, California 91101
       Contact Person: Thomas Gillogly, Ph.D.

The laboratory selected for analytical work for this study was:

       MWH Laboratories
       750 Royal Oaks Lane, Suite 100
       Monrovia, California 91016
       Contact Person: Andrew Eaton, Ph.D.

The manufacturer of the equipment was:

       Watts Premier
       1725 W. Williams Drive, #C-20
       Phoenix, Arizona 85027
       Contact Person: Shannon Murphy

MWH wishes to thank NSF International (NSF), especially Mr. Bruce Bartley, Project Manager,
and Mrs. Angela Beach, Project Coordinator, for providing guidance and program management.
MWH also wishes to thank the Coachella Valley Water District (CVWD) for providing the site
for verification testing including providing assistance in connecting to the water system and all
necessary utilities (water, sewer, and electrical).

NSF wishes to  thank Mr. Dale Scherger, Environmental Consultant, Scherger Associates, for
providing technical guidance.

Mr. Shannon Murphy and Mr. Adam Nelson, Watts Premier, are to be commended for providing
the treatment system and the excellent technical and product expertise.

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                                       Chapter 1
                                      Introduction

1.1    ETV Purpose And Program Operation

The U.S. Environmental Protection Agency (EPA) has created the Environmental Technology
Verification  (ETV)  Program  to  facilitate  the deployment  of  innovative  or  improved
environmental technologies through performance verification and dissemination of information.
The  goal  of the ETV  Program is to  further  environmental  protection by  accelerating  the
acceptance and use of improved and more cost-effective technologies.  ETV seeks to achieve this
goal by providing high-quality, peer-reviewed data on technology performance to those involved
in the design, distribution, permitting, purchase, and use of environmental technologies.

ETV works in partnership with recognized standards and  testing organizations;  with stakeholder
groups consisting of buyers, vendor organizations, and permitters; and with the  full participation
of individual technology developers.  The program evaluates  the performance of innovative
technologies by developing test  plans responsive to the needs of stakeholders,  conducting field
demonstrations,  collecting  and analyzing  data,  and  preparing  peer-reviewed reports.    All
evaluations are conducted in accordance with rigorous quality assurance protocols to ensure that
data of known and adequate quality are generated and that the results are defensible.

The EPA has partnered with NSF International (NSF) under the ETV Drinking Water Systems
(DWS) Center to verify the performance of small  drinking water  systems that serve small
communities.  A goal of verification testing is to enhance and facilitate the acceptance of small
drinking water treatment equipment by state drinking water regulatory officials and consulting
engineers,  while  reducing  the  need  for  testing  of equipment  at  each location  where  the
equipment's use is contemplated. NSF meets this goal by working with manufacturers and NSF-
qualified Field Testing Organizations (FTOs) to conduct verification testing under the approved
protocols.  It is important to note that verification of the equipment does not mean the equipment
is "certified" by NSF or "accepted" by EPA.  Rather, it recognizes that the performance of the
equipment has been determined and verified by these organizations for those conditions tested by
the FTO.

The ETV DWS  Center evaluated the performance of the Watts Premier M-Series  M-15,000
Reverse Osmosis (RO) Treatment System, which  is  a membrane technology used in drinking
water treatment system applications.  The verification test evaluated the ability of the RO system
to remove arsenic from  drinking water under specific feed water quality and  conditions. This
document provides the verification test  results for the M-15,000 RO Treatment System.

1.2    Testing Participants And Responsibilities

The ETV  testing of  the M-15,000 RO Treatment System was  a  cooperative effort among  the
following participants:

       NSF International
       MWH

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       Watts Premier
       MWH Laboratories
       U.S. Environmental Protection Agency

The  following  is  a brief  description  of all  of the ETV participants  and their  roles and
responsibilities.

1.2.1   NSF International

NSF is an  independent,  not-for-profit testing and certification organization dedicated to public
health  and safety and to the protection of the environment. Founded in 1946 and located in Ann
Arbor,  Michigan, NSF has been instrumental in the development of consensus standards for the
protection of public health  and the environment.  NSF also provides testing and  certification
services to  ensure products bearing the NSF Name, Logo and/or Mark meet those standards. The
EPA partnered with NSF to verify the performance of drinking water treatment systems through
the EPA's ETV Program.

NSF provided technical  oversight of the verification testing  and conducted an audit of the field
analytical data gathering and recording procedures.  NSF also provided review of the  Product
Specific Test Plan (PSTP) as well as this report.

Contact Information:
       NSF International
       789 N. Dixboro Road
       Ann Arbor, MI 48105
       Phone: (734) 769-8010
       Fax: (734)769-0109
       Contact: Bruce Bartley, Project Manager
       Email: bartley@nsf.org

1.2.2   Field Testing Organization

MWH, an  environmental engineering consulting firm,  conducted the verification testing of the
M-15,000 RO Treatment System. MWH is an NSF-qualified FTO for the ETV DWS Center.

The FTO was responsible for conducting the verification testing for 31 calendar days.  The FTO
provided all needed logistical support, established a communications network, and scheduled and
coordinated activities of all participants.  The  FTO  was responsible for ensuring the testing
location and feed water  conditions  were such that the  verification testing  could meet its  stated
objectives.    The  FTO  prepared the PSTP;  oversaw the  pilot testing;  managed,  evaluated,
interpreted, and reported on the data generated by the testing; and evaluated and reported on the
performance of the technology.

FTO employees conducted the on-site analyses and data recording during the testing.  The FTO's
project engineer and project manager provided oversight of the daily tests.

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Contact Information:
       MWH
       300 N. Lake Avenue, Suite 1200
       Pasadena, CA 91101
       Phone: (626) 568-6010
       Fax: (626) 568-6015
       Contact Person: Thomas Gillogly, Ph.D
       Email: Thomas.Gillogly@MWHGlobal.com

1.2.3   Manufacturer

The  treatment  system  is manufactured by  Watts Premier, a  water treatment equipment
manufacturer and supplier.  The  manufacturer was responsible for supplying a field-ready M-
15,000 RO Treatment System equipped with all necessary components, including treatment
equipment, instrumentation and controls and an operation and maintenance (O&M) manual. The
manufacturer was responsible for providing logistical and technical support, as needed, as well
as technical assistance to the FTO during operation and monitoring of the equipment undergoing
field verification testing.

Contact Information:
       Watts Premier
       1725 W. Williams Drive, #C-20
       Phoenix, Arizona 85027
       Phone: (623)505-1514
       Fax: (623)931-0191
       Contact Person: Shannon Murphy
       Email: murphysp@wattsind.com

1.2.4   A nalytical Laboratory

The specific responsibilities  of the water quality analytical staff, MWH Laboratory, were to
provide all off-site water quality analyses  prescribed  in the PSTP according to the Quality
Assurance/Quality Control (QA/QC) and the protocols contained  therein, provide reports with
the  analytical results to the data  manager, and provide detailed information on the analytical
procedures implemented.

Contact Information:
       MWH Laboratories
       750 Royal Oaks, Suite 100
       Monrovia, CA 91016
       Phone: (626)386-1100
       Fax: (626)386-1101
       Contact Person: Andrew Eaton, Ph.D.
       Email: Andrew.Eaton@MWHGlobal.com

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1.2.5  U.S. Environmental Protection Agency

The  EPA,  through its  Office of  Research and  Development,  has  financially  supported and
collaborated with NSF under Cooperative Agreement No. R-82833301.  This verification effort
was  supported by the DWS Center operating under the ETV Program. This document has been
peer reviewed, reviewed by NSF and EPA, and recommended for public release.

1.3    Verification Testing Site

The  test site selected for the verification testing of the M-15,000 RO Treatment System was the
Coachella Valley Water District's (CVWD) Well  7802 located in Thermal,  California.   The
following sections provide additional information on the test  site  (source water characteristics
and discharge method).

1.3.1  Source Water

The  feed water used during the verification study  was a  chlorinated source, with an average free
chlorine residual of 0.47 milligrams per liter (mg/L). The chlorine  enters the distribution system
at the discharge manifold, and was fed  from  a Hammond's tablet  feeder  using  calcium
hypochlorite tablets as the chlorine source.  A summary  of the  average feed water quality values
from the 27 days of operation during the verification testing is  presented in Table  1-1. Complete
descriptions of the verification testing results and quality assurance/quality control procedures
are included in Chapters 3 and 4.

Table 1-1: Average Feed Water Quality during Verification Testing
Parameter
Total Arsenic
Dissolved Arsenic

Arsenite (As (III))
Arsenate (As(V))1
Total Organic
Carbon (TOC)
Calcium
Chloride
Hardness
Alkalinity
Free Chlorine
Total Chlorine
pH2
Temperature
Number of
Units Samples
Mg/L
Mg/L

Mg/L
Mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
--
°C
27
5

5
5
5
5
5
5
5
18
18
27
54
Average
14
14

3.7
11
<0.50
4.8
8.5
18
83
0.47
0.51
9.21
27.5
Parameter
Turbidity
Conductivity
Total Dissolved
Solids (TDS)
Total Suspended
Solids (TSS)
Manganese
Iron
Barium
Silica
Fluoride
Sulfate
Chromium
Vanadium

Number of
Units Samples
NTU3
umoh/cm

mg/L
mg/L
Mg/L
mg/L
Mg/L
mg/L
mg/L
mg/L
Mg/L
Mg/L

5
24

27
5
5
5
5
5
5
5
5
5

Average
0.40
231

140
<10
<2.0
0.019
7.1
15
0.80
20
13
49

  As (V) is a calculated value.
  pH is reported as the median, not the average.
  Nephelometric Turbidity Unit(s).

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1.3.2  Pilot Effluent Discharge

All treated water (RO  permeate) and waste (RO concentrate) were blended back together and
sent to a blow-off drain for disposal, see clear  1-inch flexible tubing in Photograph  1.    The
blended water produced from the equipment being tested was not anticipated to adversely impact
the environment, as the quality of the blended  water was equivalent to the well's raw water
quality, with the exception of chlorine. The blow-off drain had sufficient capacity to accept the
blended water (treated  and concentrate) flow rate for the duration of the study. De-chlorination
tablets were added to the drain where the water from the verification unit  was discharging.
      Permeate and concentrate
      discharge lines
                Photograph 1: Permeate and Concentrate Discharge Lines

1.3.3 Discharge Permits

No discharge permits were necessary for this verification study.

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                                       Chapter 2
                     Equipment Description and Operating Processes
2.1    Equipment Description

The equipment tested in the ETV was the M-15,000 RO Treatment System.  The M-15,000 RO
Treatment System verification unit contains six pressure vessels, each containing one 4" x 40"
membrane module.  Each stainless  steel pressure vessel is 4 inches (10 cm)  in diameter and
approximately 45 inches (110 cm) long. A schematic of the system is shown in Figure 2-1 and a
photograph of the unit is shown in  Photograph 2, which specifically shows the panel mounted
flow meters, pressure gauges,  recirculation needle valve, and individual membrane sample ports.
                     531/2
                                                       -283/4-
fl5P
n
                                           V230VAC/15A

                                     ,,-Water Supply Utility Connection (cold = 1" NPT)

                                    / ,-Permeate Connection (1" NPT)
                                     /
                                        oncentrate / Drain (1.25" NPT minimum)
          Figure 2-1: Watts Premier M-Series M-15,000 RO Treatment System.

The feed water is initially passed through a pre-filter (sediment filter or carbon bloc for chlorine
removal) to remove particles that have the potential to damage the membrane.   There is  a
sampling port just prior to the pre-filter to collect the feed water samples.  After passing through
the pre-filter, the  feed water is blended with re-circulated concentrate water and is then referred
to as the inlet water.  The inlet water is then sent through a booster pump and after leaving the
discharge side  of the pump, the water line is split and feeds the two separate banks of membranes

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(three membranes per bank, six membranes in total), starting with membrane 1 and 4. For the
first bank of membranes, concentrate from membrane 1  feeds membrane 2 and concentrate from
membrane  2 feeds  membrane 3.  For  the second  bank  of  membranes, concentrate  from
membrane 4 feeds membrane 5 and concentrate from membrane  5 feeds membrane 6.  Permeate
from all membranes is collected from the bottom of the housing and exits the unit as drinking
water.  There is a permeate sample port for each of the six membranes, as well as the blended
permeate from all six of the  membranes. During the verification test, permeate samples were
collected from the blended permeate sample port.  Concentrate from membranes 3 and 6 is split,
some being purged to waste and some re-circulating back to the head of the system, just after the
pre-filter where it is blended with the feed water to create the inlet water. The concentrate that is
re-circulated back to the head of the system is referred to as recycle water.  A process flow
diagram of the flow  streams through the M-15,000 RO Treatment System is presented in Figure
2-2.
  Figure 2-2:  Watts Premier M-15,000 RO Treatment System process flow diagram and
                                   sample locations.

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Photograph 2: Watts Premier M-15,000 RO Treatment System at CVWD Well 7802

The recycle rate was determined during the initial shake down period, but was expected to be
75% at 130 to 150 pounds per square inch (psi) (based on the manufacturer's experience)  and
was manually adjusted through a recirculation needle control valve.  For a standard M-15,000
RO Treatment System, recycle ratio is not a measured operational parameter. For the verification
study, the recycle flow rate was monitored through a flow meter (not a standard part) located on
the recycle water line in order to  calculate the recycle ratio and  determine the  tne osmotic
gradient across the membranes.

The qualitative, quantitative and cost factors of the tested equipment were identified, in so far as
possible, during the verification testing.   The relatively  short duration of the study  created
difficulty in reliably identifying some of these factors.  The qualitative factors examined during
the verification were operational aspects of the M-15,000 RO Treatment System; for example,
susceptibility to changes in environmental  conditions,  operational requirements and equipment
safety, as well  as other factors that might  impact performance.   The  quantitative  factors
examined during the verification testing process were costs associated with the system, such as
power,  filter  cartridge  replacement, cost of operation and  disposal  costs.   The  operating
conditions were recorded in the project logbook.  Specific information regarding the membrane
plant design criteria and membrane element characteristics may be found on Table 2-1 and Table
2-2.
                                            8

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Table 2-1: Membrane Plant Design Criteria Reporting Items
Parameter
            Value
Number of Stages
Number of Pressure Vessels in Stage 1
Number of Pressure Vessels in Stage 2
Number of Membrane Elements per Pressure Vessel
Recovery per Stage (%)
Recovery for System
Design Flux
Pressure Loss per Element
Pressure Loss in Stage Entrance and Exit
Feed Stream IDS (mg/L)
IDS rejection
Rejection of Specific Inorganic Constituents	
              2
              1
              6
              1
            NA1
            50%
            12gfd2
            6 psi
            ISOpsi
Based on Influent Water Quality
           95-99%
           80-99%
1  NA = Not available.
2  Gallons per square -foot per day.
Table 2-2: Membrane Element Characteristics
Parameter
            Value
Membrane Manufacturer
Membrane Element Model Number
Size of Element Used in Study
Active Membrane Surface Area per Element
Molecular Weight Cut-Off
Membrane Material Construction
Membrane Hydrophobicity
Reported Membrane Charge
Spacer Thickness
Scroll Width
Design Pressure
Design Flux at Design Pressure
Variability of Design Flux
Design Specific Flux at  25 °C
Standard Testing Recovery
Standard Testing pH
Standard Testing Temperature
Design Cross-Flow Velocity
Maximum Flow Rate to an Element
Minimum Flow Rate to an Element
Required Feed Flow to Permeate Flow Ratio
Maximum Element Recovery
Rejection of Reference  Solute and Conditions of Test (e.g., Solute type and
concentration)
Variability of Rejection of Reference Solute
Acceptable Range of Operating Pressures (psi, bar)
Acceptable Range of Operating pH Values
Typical Pressure Drop across a Single Element
Maximum Permissible Silt Density Index (SDI)
Maximum Permissible Turbidity
Chlorine/Oxidant Tolerance
Suggested Cleaning Procedures
           Applied
        M-T4040 ALE
           4" X 40"
            82ft2
       80- lOODaltons
         Dow Filmtec
         Hydrophobic
           Negative
            31  mil
           38 inches
           ISOpsi
           34gfd
           ± 15%
         0.24 gfd/psi
           50-75%
              8
            25°C
           0.6ft/s
   16 gallons per minute (gpm)
            4 gpm
             1:5
             75%
           80-99%

           -0%, +1%
Dependent on Water Temperature
            2- 11
            6 psi
              4
           1 NTU
    With Carbon Pre -Filter
M-l 5,000 RO Treatment System
   has a self-flush procedure.

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2.2    Operating Process

RO is a pressure-driven process, with the pressure used for separation by allowing fresh water to
move  through  a membrane,  leaving various  dissolved constituents of the water  behind.
Scientists have explored this concept since the turn of the century, but commercialization for
desalting water for municipal purposes has occurred in only the last 30 to 40 years.

For this  separation process, water  from a pressurized  saline solution is separated  from the
dissolved inorganic and  organic compounds by flowing through a membrane.  No heating  or
phase change is necessary for this separation.   The major energy required for desalting is for
pressurizing the  feed water.  The saline feed water is pumped into a closed vessel where it is
pressurized against the membrane.  As a portion of the water passes through the membrane, the
remaining feed water increases in salt content.  At the same time, a portion of this feed water is
discharged without passing through the membrane.

The amount of water that can be passed through the membrane is frequently controlled to  avoid
problems with precipitation of super-saturated salts and increased osmotic pressure across the
membranes. The amount of the feed water discharged to waste in the concentrate stream varies
from  15  to 70% of the feed  low, depending on the inorganic composition of the feed water,
pressure, and type of membrane.  The RO membranes vary in their ability to reject the  passage
of inorganics, including the various arsenic compounds detected in the environment.

As this treatment does not destroy arsenic, the total mass of arsenic exiting the  system equals the
mass  entering the system. Consequently, the amount of arsenic that has been "removed" from
the permeate (treated water) can be found in the wasted concentrate.

Referring to Figure 2-1, the  M-15,000 RO Treatment  System used in the verification testing
included:

•      3 Hp single phase motor and stainless steel centrifugal pump,
•      Pre-filter for removal  of small debris (sediment, rust, and other suspended solids) and
       residual chlorine (first 18 days of testing) and a cartridge pre-treatment filter (last 13 days
       of testing) (see Photograph 3),
•      Panel mounted flow meters (to monitor permeate, concentrate, and recycle flow),
•      Recycled water flow meter (not a standard part for the M-15,000 RO Treatment System)
       located on the recycle line prior to cartridge pre-filter,
•      Manual recirculation needle control valve,
•      Panel mounted digital conductivity meter (permeate water),
•      Membrane test ports,
•      Glycerin  filled pressure gages (used to monitor inlet and feed water pressure),
•      Six stainless steel pressure vessels, and
•      Six 4" x 40" RO modules.
                                            10

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        Photograph 3: Pre-Filter to Watts Premier M-15,000 RO Treatment System

The inlet and feed water pressure were monitored by the glycerin filled pressure gages that had a
range of 0 to 300 psi.  The permeate and concentrate flow rates were measured by the panel
mounted flow meters that had a range of 0-20 gpm.  The recycle flow meter also had a range of 0
to 20 gpm.

Specific feed water operating parameters, electrical  and drain requirements, as well as additional
specifications for the M-15,000 RO Treatment System are presented in Table 2-3.

Table 2-3: Watts Premier M-15,000 RO Treatment System Specifications
 Specifications
M-15,000 RO System
 Dry Weight
 Wet Weight
 Feed Water Parameters
 Temperature
 Max Feed Flow Rate
 pH
 Maximum Hardness
 Maximum TDS
 Maximum Iron
 Pressure
 Drain Connection Requirements
 Floor Sink Minimum within 10' of RO system
 Electrical Requirements
 RO Processor Optional 220V
 Delivery Pump	
950 Ibs
4900 Ibs

35tolOO°F
24 gpm
2 to 11
290 mg/L
2500 mg/L
0.1 mg/L
50 to 150 gauge pressure (psig)

1 %" connection

220 volts/11.5 amps
115 volts/12.4 amps	
The flow rate was regulated by a flow meter and control valve to maintain a constant flow, which
were mounted on the RO control panel.  Raw water was supplied to the verification testing unit
                                             11

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using a pressurized feed line (approximately 80 to 90 psi) and a 3 Hp centrifugal pump was used
to increase  the pressure  to  the RO  operating  conditions of  -150  psi.   The  raw water
(approximately at 24 gpm) was first passed through a 20" carbon bloc pre-filter to remove any
small debris, other suspended solid particles, and residual chlorine.  The carbon pre-filter was
replaced with a 20-micron sediment pre-filter (20 inch, Watts Premier Big Blue pleated sediment
filter; the Watts Premier poly spun sediment filter model number WP204020 may also be used)
after 18 days of operation, due to a high replacement rate (approximately every 7  days) of the
carbon pre-filter.
                                           12

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                                         Chapter 3
                                 Methods and Procedures

3.1 Quantitative and Qualitative Evaluation Criteria

The objectives of the ETV were to evaluate the equipment in the following areas:

•      Performance relative to the manufacturer's (Watts  Premier) stated range of equipment
       capabilities,
•      The impacts on performance of variations in feed water quality (such as TDS, hardness,
       temperature, pH, alkalinity and iron),
•      The logistical, human and economic resources necessary to operate the equipment, and
•      The reliability, ruggedness, cost factors, range  of usefulness and ease of operation of the
       equipment.

In order to address these  objectives, the ETV employed the quantitative and qualitative factors
listed in Table 3-1 in evaluating the RO equipment performance.

  Table 3-1: Quantitative  and Qualitative Evaluation Criteria

              Quantitative Factors                            Qualitative Factors
  •    Flux                                  •    Ease of operation
  •    Feed water recovery                      •    Safety
  •    Finished water quality                     •    Susceptibility to environmental conditions
  •    Range of feed water quality that were treated   •    Ruggedness
       successfully                            •    Impact of operator experience on successful
  •    Power consumption                           operation
  •    Maintenance requirements                 •    Portability of equipment
  •    Required level of operator attention          •    Modular nature of equipment (ease of capacity
  •    Spatial requirements                           expansion)
  •    Feed flow requirements
  •    Discharge requirements
  •    Waste disposal	

The  primary  applications   of RO  are  the removal  of dissolved  inorganic  and  organic
contaminants.  In the case of this ETV test, the primary application was arsenic removal.

3.2 Key Treated Water Quality  Parameters

3.2.1   Key Groundwater Quality Parameters the Equipment is Designed to Address

The operating range of the manufacturer's RO membrane is summarized in Table 3-2.
                                             13

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  Table 3-2: Operating Range of Watts Premier RO Membrane

 	Parameter	Range
                  Arsenic                                  Less than 350
                    IDS                                  Less than 2,500 mg/L
                  Hardness                                 Less than 290 mg/L
                    Iron                                   Less than 0.1 mg/L
                    pH                                        2 to 11
              Chlorine exposure                Not chlorine tolerant without a carbon filter (which was
 	included during a portion of the study)	
  1 For verification testing, the range of arsenic was anticipated to be < 50 (ig/L.


3.2.2 Key Treated Water Quality Parameters for Evaluating Equipment Performance

Key treated water quality parameters that were employed for evaluation of the manufacturer's
RO system equipment are listed in Table 3-3.

 Table 3-3: Key Treated Water Quality Parameters

	Water Quality	Inorganic Parameters	Other Parameters	
          Temperature                   Arsenic            Langelier Saturation Index (LSI)
           Alkalinity                  Conductivity                      SDI
           Hardness                     Silica
              pH                       Fluoride
           Turbidity                      Iron
             TOC                     Manganese
            Chloride                     Sulfate
      Free and Total Chlorine              Chromium
                                       Vanadium
                                         TDS
                                          TSS
                                        Calcium
                                        Barium

3.3   Calculations

3.3.1 Calculation of Statistical Uncertainty

The  count, average,  minimum, and maximum  values were tabulated for all data sets.  For the
water  quality parameters described above,  95% confidence intervals were  calculated for
parameters with  more than eight data points.  The following equation was used for confidence
interval calculation:
           Confidence Interval = X +1
where:   X =  sample mean;
         S = sample standard deviation;
                                            14

-------
         n =  number of independent measurements included in the data set; and
         t = Student's t distribution value with n-1 degrees of freedom;
         oc= significance level, defined for 95% confidence as: 1-0.95 = 0.05.

According to the 95% confidence interval approach, the a  term is defined to have the value of
0.05, thus simplifying the equation for the 95% confidence interval in the following manner:

                                      —         ( s^
              95% Confidence Interval = X ±tn_l0975\ —=
With input  of the analytical results for pertinent  water quality parameters  into the  95%
confidence interval equation, the output is presented as the sample mean value plus or minus the
second term. The results of this statistical calculation are presented as a range of values falling
within the 95% confidence interval.

3. 3. 2 Calculation and Definition of Operational Parameters

The following are definitions used in the calculations presented within this section:

Permeate water is defined as the water produced by the RO  membrane process.

Feed water is defined as the water introduced to the membrane element (no recycled water).

Inlet water is the combination of the feed water and the recycled concentrate water.

Concentrate water is the concentrated waste stream produce by the RO membrane process.

Recycled water is a portion of the concentrate water recirculated back through the RO membrane
process, blended with feed water entering into membranes 1  and 4.

Permeate flux is the flow of permeate divided by the surface area of the membrane.

Permeate flux was calculated according to the following formula:
                                                                             (3D
where:   Jt    = permeate flux at time t (gfd)
         Qp   = permeate flow (gallons per day (gpd))
         S    = membrane surface area (ft2)
                                           15

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Temperature Adjustment for Flux Calculation: Temperature corrections to 25°C for permeate
flux and specific flux were made to correct for the variation of water viscosity with temperature.
The following empirically derived equation was used to provide temperature corrections for
specific flux calculations:
                                  -0.0239(1-25)
               rt (at 25 °C) =
                                                                             (3.2)
where:  Jt    = permeate flux at time t (gfd, L/(h-m2))
        Qp   = permeate flow (gpd, L/h)
        S    = membrane surface area (ft2,
        T    = temperature of the feed water (°C)
m2)
Net Driving Pressure:  The Net Driving Pressure is the pressure available to drive water
through the membrane,  equal  to  the  average  feed pressure  (average  of feed  pressure  and
concentrate pressure) minus the differential osmotic pressure, minus the permeate pressure:
              NDP =
                      (Pf+Pc)
                                    (3.3)
where:  NDP = net driving pressure for solvent transport across the membrane (psi, bar)
        Pf    = inlet pressure to the feed side of the membrane (psi, bar)
        Pc    = concentrate pressure on the concentrate side of the membrane (psi, bar)
        Pp    = permeate pressure on the treated water side of the membrane (psi, bar)
        ATI   = osmotic pressure (psi)

Osmotic Pressure Gradient:   The term osmotic pressure gradient  refers to the difference in
osmotic pressure generated across the membrane barrier as a result of different concentrations of
dissolved salts. The following equation provides an estimate  of the osmotic  pressure across the
semi-permeable membrane through generic use of the difference in TDS concentrations on either
side of the membrane:
                          +TDSC)'
                                 -TDS
  I psi
                                          100
                                             mg
                                                                             (3.4)
where:   TDSi = inlet water (feed water + recycled water) TDS concentration (mg/L)
         TDSC = concentrate TDS concentration (mg/L)
         TDSP= permeate TDS concentration (mg/L)

The inlet water (feed water plus recycled water) characteristics were calculated based on the feed
water, permeate, and concentrate TDS and conductivity.
                                           16

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Note that the different proportions of monovalent and multivalent ions composing the TDS will
influence the actual  osmotic pressure, with lower unit pressures resulting from multivalent
species. The osmotic pressure ratio of 1 psi per 100 mg/L is based upon TDS largely composed
of sodium chloride.  In contrast, for TDS composed of multivalent ions, the ratio is closer to 0.5
psi per 100 mg/L TDS. This was accounted for during verification testing.

Specific Flux: The term specific flux is used to refer to permeate flux that has been normalized
for the net  driving pressure.  The equation used  for calculation of specific flux is given by the
formula provided below.   Specific  flux is usually discussed with use of  flux values that have
been temperature-adjusted to 25°C:


                                                                            (3.5)
where:  NDP = net driving pressure for solvent transport across the membrane (psi, bar)
        Jt   = permeate flux at time t (gfd, L/(h-m2)). Temperature- corrected flux values were
             employed.

Water Recovery:  The recovery  of  feed water as permeate water  is given as the ratio of
permeate flow to feed water flow:
              Yo System Recovery = 100 •
(3.6)
where:  Qf  = feed water flow to the membrane (gpm, L/h)
        Qp  = permeate flow (gpm, L/h)

Recycle Ratio:  The recycle ratio represents the ratio  of the recycle flow from the membrane
concentrate to the total flow of water that is used as feed water flow to the membrane. This ratio
provides an idea of the recirculation pumping that is applied to the membrane system to reduce
membrane fouling and specific flux decline.
                                  Q,
              RecycleRation=  	
                                                                            (37)
where:  Qr  = recycle water flow rate (gpm)
        Qf  = feed water flow rate (gpm)
                                           17

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Solute Rejection:  Solute rejection is controlled by a number of operational variables that must
be reported at the time  of water sample collection.  Bulk rejection of a targeted inorganic
chemical contaminant were calculated by the following equation:
              % Solute Rejection = 100 •
(3.8)
where:   Cf   = feed water concentration of specific constituent (mg/L)
         Cp   = permeate concentration of specific constituent (mg/L)

Note: the feed water concentration does not include the recycled water.

Solvent and Solute Mass Balance:  Calculation of solvent mass balance was performed during
Task  1  in  order  to  verify  the reliability of  flow  measurements  through the  membrane.
Calculation of solute mass balance across the membrane system was performed as part of Task 3
in order to estimate the concentration of total arsenic at the membrane surface.

              Qf=QP + Qcw                                                    (3.9)

              QfCf=QpCp + QcwCc                                          (3.10)

where:   Qf   = feed water flow to the membrane (gpm, L/h)
         Qp   = permeate flow (gpm, L/h)
         Qcw  = concentrate (wastewater) flow (gpm, L/h)
         Cf   = feed water concentration of specific constituent (mg/L)
         Cp   = permeate concentration of specific constituent (mg/L)
         Cf   = concentrate concentration of specific constituent (mg/L)

Solubility Product:  Calculation of the solubility product of selected sparingly soluble salts was
performed to  determine if there were  operational limitations caused by the accumulation  of
limiting salts at the membrane surface.   Textbook equilibrium values of the  solubility product
were compared with solubility values  calculated  from the  results  of experimental verification
testing, as determined from use of the following equation:


                                                                             (3.H)

where:   Ksp   = solubility product for the limiting salt being considered
         y    = free ion activity coefficient for the ion considered (i.e., A or B)
         [A]   = molar solution concentration of the anion A for sparingly soluble salt AxBy
         [B]   = solution concentration of the anion B
         x, y  = stiochiometric coefficients for the precipitation reaction of A and B
                                            18

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Mean Activity Coefficient: The mean activity coefficients for each of the salt constituents were
estimated for the concentrated solutions as a function of the ionic strength:
lagyAJI= -0.509-
                                                                             (3.12)
where:   y    = free ion activity coefficient for the ion considered (i.e., A or B)
         ZA   = ion charge of anion A
         ZB   = ion charge of cation B
         (j,    = ionic strength

Ionic Strength:  A simple approximation of the ionic strength was calculated based upon the
concentration of the IDS in the feed water stream:
                                                                             (3.13)
where:   (J,    = ionic strength
         IDS = total dissolved solids concentration (mg/L)

3.4 Testing Schedule

The  ETV schedule is  presented in Figure 3-1.  The testing took place over a  total  period of
approximately eight weeks beginning during the second week of April 2004, and ending in late
May 2004. The five tasks are described in further detail in Sections 3.7 and 4.1.
Task
1
2
3
4
5
Descrintion
Preparation, Coordination, and Setup
Membrane Operation
Cleaning Efficiency
Feedwater and Treated Water Quality Monitoring
Data Handling Protocol
Quality Assurance Project Plan
Year - 2004
12-Acr 19-Acr 26-Acr 3-Mav 10-Mav 17-Mav 24-Mav 7-Jun


I

I




                       Figure 3-1:  RO verification testing schedule.

Verification testing activities included equipment set-up, initial operation, verification operation,
membrane cleaning, and sampling  and analysis.  Initial operations were conducted  so that
equipment could tested and to be sure it is functioning as intended.
                                            19

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3.5 Operation and Maintenance

The manufacturer's operation and maintenance (O&M) documentation for the  M-15,000 RO
Treatment System was reviewed prior to the verification testing.  The O&M manual for the M-
15,000 RO Treatment System may be found in Appendix A of this report. In addition, the
following aspects of operability are addressed in this report:

•      Fluctuation of flow rates and pressures through membrane unit  - the time interval at
       which resetting is needed (i.e., how long can feed pumps hold on a set value for the feed
       rate?)
•      Presence  of devices to aid the operator with flow control adjustment?
•      Was transmembrane pressure measurement provided?
•      Was recycle ratio measurement provided?
•      Was feed water recovery measurement provided?
•      Was rate  of flow of raw water measured?
•      Did the plant have an indicator if the sediment pre-filter was changed ahead of scheduled
       quarterly  maintenance schedule?
•      Did the carbon pre-filter adequately remove chlorine?

3.6 Field Operations Procedures

Testing of the M-15,000 RO Treatment System was conducted by an NSF-qualified FTO, MWH.
Water quality  analytical work that was carried out as a part of the verification testing plan, was
conducted by MWH Laboratories. All arsenic analyses were  conducted  by MWH Laboratory.
Field analytical work was performed by MWH field personnel using field laboratory equipment
and procedures for pH, temperature, conductivity, chlorine, turbidity, alkalinity, and hardness.

The verification  unit was operated 24 hours a day, seven days a week with staff on-site each day
to operate the  verification unit and collect water quality data during one eight-hour shift.  Tasks
performed by the operations staff are described in detail below.

3.7 Environmental Technology Verification Testing Plan

The  following  section provides  a  brief  overview  of  the tasks  included  in the  initial
characterization tests and the tasks included in the M-15,000 RO Treatment System verification
testing plan. The verification tasks included:

Task 1: Membrane  Operation
Task 2: Cleaning Efficiency
Task 3: Feed water and Treated Water Quality Monitoring
Task 4: Data Handling Protocol
Task 5: Quality  Assurance Project Plan (QAPP)

Verification testing  activities included equipment set-up, initial  operation, verification operation,
and sampling and analysis.  Initial operations were  conducted so that equipment could be tested
                                           20

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to be sure it was functioning as intended.  An overview of each task is provided below with
detailed information following this section of the report.

3.7.1   Task 1: Membrane Operation

The  objective of this  task  was to evaluate the RO  membrane system  operation.   System
performance  was  evaluated relative  to  the  stated  water quality  goals  specified by  the
manufacturer.  Membrane productivity, rate of specific flux decline, and rejection capabilities
were evaluated at one set of operating conditions for the testing period.

3.7.2   Task 2: Cleaning Efficiency

The objective  of this task was to evaluate the efficiency of the membrane  cleaning procedures
recommended by the manufacturer. Watts Premier recommends replacement of the RO modules
based upon efficiencies of TDS reduction per module.  TDS reduction of the membranes would
need to be monitored in order to determine if replacement of the membranes is necessary.  Watts
has stated that the M-15,000 RO Treatment System has a built in flushing procedure;  however,
since  the verification test was run continuously, the system did not go through this flushing
procedure. However, at the conclusion of the testing period, the cartridge sediment pre-filter and
RO module O-rings were replaced according to the manufacturer's  recommended  quarterly
maintenance procedures. While not part  of the quarterly maintenance procedures, two of the
membranes (membrane number 5 and 6) were also replaced during the maintenance procedures.
The  operational performance following  these  maintenance  procedures  was  recorded  and
presented in Chapter 4 of this report.

3.7.3   Task 3: Feed Water and Treated Water Quality Monitoring

The objective of this task was to evaluate the quality of water produced by the membrane system
and the removal of inorganic chemical contaminants achieved by the membrane system at the
specified operational conditions.   Monitoring of the water quality parameters  included  the
following:  arsenic  (total,  dissolved and As  (III)), pH,  feed water  temperature,  chloride,
conductivity, calcium, barium, hardness,  chlorine, TDS, alkalinity, LSI, turbidity, TSS, silica,
fluoride, iron, manganese, sulfate, chromium, vanadium, TOC and SDL Water quality  produced
was evaluated in relation to feed water quality and operational conditions.   Mass balances were
calculated to determine the  accumulation of limiting salts on the membrane surface.  Post-
treatment  capabilities  of the  equipment  were also evaluated  for arsenic  (total, As+3,  and
dissolved), pH adjustment, corrosion control, and removal of carbon dioxide  from the permeate.

An overview of the equipment operational and production characteristics evaluated for  each task
of the verification testing is provided in Table 3-4.
                                           21

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Table 3-4: Equipment Operational Characteristics to be Evaluated in Each Task
Equipment Operational Characteristic to be Evaluated Task
1.
2
3.
4.
5.
6.
7.
8.
9.
10.
11.
Feed water flow rate
Permeate flow rate
Concentrate flow rate
Inlet and Outlet pressures to membrane element
Permeate pressure
Feed water temperature
Recycle Ratio
Power consumption
Permeate stream characterization
Calculation of limiting salt concentrations
Waste stream characterization and range of waste stream flow rates
1
1
1
1
1
1
1
1
3
o
J
1 and 3
3.7.4  Task 4: Data Handling Protocol

The  objective of this task was to establish an effective field protocol for data management at the
field operations site and for data transmission between the FTO  and NSF during verification
testing.   Prior to the beginning of  field testing,  the database  or spreadsheet design were
developed by the FTO and reviewed and approved by NSF. This insured that the required data
was  collected  during  the testing, and that results could be effectively transmitted to NSF for
review.

3.7.5  Task 5: Quality Assurance Project Plan (QAPP)

An important aspect  of verification  testing is  the Quality  Assurance  Project Plan (QAPP)
developed for QA/QC.   The  objective of this  task was to  assure  accurate measurement of
operational and water  quality parameters during membrane equipment verification testing.

3.8 Task 1: Membrane Operation

Membrane operation was evaluated in Task 1, with quantification  of temperature-corrected rate
of specific flux decline  and water recoveries.  The  rates of specific  flux decline were  used to
demonstrate membrane performance  at  the specific  operating  conditions  to be  verified.
Monitoring in Task 1 was focused on determination of the system  operational  characteristics
(e.g., arsenic removal, flux, temperature-corrected specific flux, recovery, etc.).   An NSF field
inspection of equipment operations, sampling,  and field analysis procedures was carried out
during the initial test runs in Task 1 (results presented in Chapter 4).

Rate of temperature-corrected specific flux decline is a function of water quality and operational
strategy.  Many additional factors influence specific  flux decline with RO membranes including
membrane compaction,  inorganic scaling,  particulate or organic fouling,  biofouling, and other
factors.   In this task,  specific flux  decline was  monitored to  evaluate operational  trends.
Chemical characterization of the feed waters and permeate water stream with  calculation of
membrane rejection capabilities were performed as part of Task 3.  Additionally, calculation of
the operational limitations caused by limiting salt concentrations was also performed in Task 3.
                                           22

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3.8.1  Experimental Objectives

The objectives  of Task 1 were to demonstrate the  following:  1) the appropriate  operational
conditions for the membrane equipment; 2) the feed water recovery achieved by the membrane
equipment  at the designated operational conditions;  and 3) tie  rate of specific flux decline
observed over extended membrane filtration operation during the testing  period. This task was
also intended to  provide  operational  power consumption information that could  be  used  to
develop  cost estimates  for  O&M  of the equipment.    Complete chemical  and  physical
characterization of the feed waters and treated  waters produced by the system, with calculation
of limiting salt concentrations, were performed as part of Task 3.

It should be noted  that the objective of this task was  not process optimization, but rather
verification of membrane operation at the operating conditions specified by the FTO, as pertains
to permeate flux and transmembrane pressure.

3.8.2  Work Plan

Site preparation, coordination, mobilization and start-up of equipment were performed prior to
the initiation of Task 1 testing.  Furthermore, the RO membrane treatment system had achieved a
condition of steady-state operation prior to the start of Task 1 testing.

After  set-up and  shakedown of the membrane equipment, RO operation was established at a
specific flux  of 0.38 gfd/psi  with a feed water recovery of 69%.   It was intended  that the
membrane system would be operated continuously for  a minimum of  one month.  However, the
system automatically shut  itself down twice  during  the verification testing, and  was not in
operation for a total of four days during the verification testing period. The system was  operated
for a  total of 27 days during the verification test.  A summary  of the operational parameters
recorded during Task 1  and the minimum frequency of monitoring are  presented in Table 3-5. A
summary of the water recovery and specific flux may be found in Tables 4-3 (Section 4.2.1.3)
and Table 4-6 (Section 4.2.1.5) respectively.

Samples  were collected  from lab valves mounted on the panel coming from  Vi" ball valves teed
into the permeate  line (permeate),  1" bulk fittings mounted on the top of the unit (concentrate),
1" port on the top of the unit (inlet), and a 1" housing  on the side of the panel (feed  water). The
inlet and feed water pressure were monitored by the glycerin filled pressure gages  that have a
range of 0 to 300 psi, and the permeate and concentrate flow rates were measured by the panel
mounted flow meters that have a range of 1  to 20 gpm. For a standard M-15,000 RO Treatment
System, the recycle ratio is not a measured  operational parameter.  However, for the purpose of
verification testing, a flow meter was placed on  the recycle line to calculate the recycle ratio.
                                           23

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Table 3-5:  Frequency and Type of Operating Data
Operational Parameter
Action, Monitoring Frequency
Feed Water, Permeate, Recycle, and Concentrate Flow
Rates
Membrane Element Inlet and Feed Water Pressures
Recovery

Recycle Ratio

IDS Concentration in Feed water, Concentrate,
Permeate
Feed water Temperature
Horsepower and Efficiency of Motors, and Consumed
Amperage for RO Treatment

Concentrate Composition For Disposal
Checked and recorded twice daily. Adjusted when 10%
above or below target. Recorded both before and after
adjustment. The feed water flow rate was monitored
twice daily by summing the permeate and concentrate
flow rates.
Checked and recorded twice daily.
Calculated and recorded twice daily. Adjusted when
10% above or below target.
Calculated and recorded twice daily. Adjusted when
10% above or below target.
Calculation of osmotic pressure gradient on a daily
basis.
Recorded twice daily.
Provided record of pumping requirements, current draw
to motors on cumulative basis, power factor and
recorded daily from a power totalizer.
Sampled waste stream once per week during the 31 -day
testing period.	
When a specific flux decline of 20% occurred before the  operating period  was completed,
adjustments to  the  operational strategy were made (such as  a decrease in nominal flux or
recovery).   Decisions on which adjustments  were made were  based upon the manufacturer's
experience and consultation with the FTO conducting the study.

3.8.3 Analytical Schedule

Measurement of membrane performance parameters were monitored a minimum of 2 times per
day,  as indicated in  Table 3-5.  Temperature measurements were made on a daily basis in order
to provide data for temperature correction  of  specific flux and  for reporting  of solute rejection
(addressed in Task 3).

Power use for the operation  of the RO system was monitored with a power  totalizer. Power
measurements were recorded daily by MWH during the verification test.

The  characteristics of feed waters used during  the testing period  were explicitly reported with the
compiled results from  membrane  flux, specific flux  and  recovery  monitoring.   The  TDS
concentrations in the inlet water  (combined feed  water  and  recycled  water),  permeate and
concentrate streams  were used to calculate the osmotic  pressure gradient (Equation 3.4) across
the membrane on a  daily basis.   Osmotic pressure gradient value  was used  to calculate net
driving pressure and specific flux on a daily basis.

3.8.4 Evaluation Criteria and Minimum Reporting Criteria

•      General operational performance (provided in Chapter  4):
       =>     Graph of specific flux  normalized to 25°C   (Equation  3.5)  vs. time  over the
              verification testing period.
                                             24

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       =>    Temporal profile of net driving pressure normalized to 25°C (Equation 3.3) over
             the verification testing period.
       =>    Temporal profile of water recovery (Equation 3.6)  over the verification testing
             period.   One temporal profile graph has been provided for the water quality
             evaluated.
       =>    Temporal profile of the concentrate flow and other waste stream flows produced
             during the verification testing period.
•      Power consumption (provided in Chapter 4):
       =>   A table of horsepower requirements, motor efficiency and consumed amperage for
            the  testing  period  has  been provided,  as measured for the  set of operational
            conditions during the verification testing period.
•      Concentrate  stream  characterization  (See Chapter 4, Task 3 for  the  water quality
       characteristics of the concentrate, permeate, and feed water):
       =>   A table of concentrate stream quality parameters measured during the verification
            testing period has been provided.

3.9 Task 2: Cleaning Efficiency

While no chemical cleaning procedure was provided by the manufacturer, regularly scheduled
maintenance of the system includes quarterly replacement of the pre-filter and  RO module O-
rings, and replacement of the BD modules based on  efficiencies of TDS  reduction  per filter
module.  At the end  of the testing period, the cartridge sediment pre-filter and  RO module O-
rings were replaced.  In addition to replacing the pre-filter and RO module O-rings, two of the
membranes  were  replaced  (membrane  number 5  and  6).    Measurement  of membrane
performance parameters following this maintenance were recorded and presented in Chapter 4.

3.9.1 Experimental Objectives

The  objective  of this task  was  to  evaluate the manufacturer's recommended  maintenance
procedures for ensuring reasonable operational parameters  are maintained during throughout the
treatment life of the membrane modules.  This task was considered a "proof of concept" effort,
not an optimization effort.

3.9.2  Work Plan

The membrane system has the potential to experience specific flux decline during the membrane
test run conducted for Task 1. If a 20% decline of specific flux were detected, the modules were
to be replaced and the system would then undergo the recommended maintenance procedures
specified by the manufacturer.  Following the maintenance procedures, the  system was restarted
and the initial conditions of specific flux, recovery and inorganics (arsenic) rejection capabilities
were tested.

As the manufacturer recommends  replacement  of  fouled  modules, no chemical  cleaning
procedures  were  provided.   Furthermore,  since chemical cleanings  are not  recommended,
disposal of spent cleaning agents is not relevant.
                                           25

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3.9.3 Analytical Schedule

Flow rates, pressures, recovery, and temperature data were collected immediately prior to and
immediately  after performing any manufacturer's scheduled quarterly or annual maintenance
procedures.   Based on this information,  any changes in the temperature  adjusted specific flux
were determined.  Two primary indicators of conventional cleaning efficiency and restoration of
membrane productivity were examined in this task:

1) The immediate recovery of membrane productivity,  as  expressed by  the ratio between the
   final specific flux ralue of the current filtration run  (Jtmf) and the initial specific flux (Jtm;)
   measured for the subsequent filtration run:
                                                     "/
              % Recovery   of specific  Flux  =100
                                                       tm /
                                                                            (3.14)
       where:   Jtmf = Final specific flux (gfd/psi, L/(h-m2)/bar) at end of the previous run
                Jtmi = Initial specific flux (gfd/psi, L/(h-m2)/bar) at the beginning of the current
                run.

2)  The loss of specific flux capabilities, as expressed by the ratio between the initial specific
    flux for any  given filtration run (Jtmi) divided by the original specific flux measured at the
    initiation of operation for the first filtration run in a series (Jtmio):
              % Loss of Original specific Flux =100
                                                      Jt,
(3.15)
       where:   Jtmio = Original Specific flux (gfd/psi, L/(h-m2)/bar) measured at the initiation of
                membrane testing.

3.9.4 Evaluation Criteria and Minimum Reporting Requirements

The minimum reporting requirements include presentation of the following results
•      Specific flux recovery:
       =>     A table is provided  in Chapter 4 of post maintenance specific flux recoveries
              during the period of operation.
•     Maintenance efficiency:
       =>     A table  is  provided in Chapter 4  of the maintenance efficiency  indicators
             described above for the maintenance procedures performed during the period  of
             operation.
•      Assessment of irreversible loss of specific flux and estimation of usable membrane life
       for costing purposes.
                                            26

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3.10 Task 3: Water Quality Monitoring

The water quality data for the feed water (chlorinated groundwater), the membrane permeate and
concentrate streams were collected during the verification testing as part of Task 1.  A list of the
water quality parameters monitored during equipment verification testing is provided in Table 3-
6.

Table 3-6: Sampling Schedule and Methods for Feed, Permeate, & Concentrate Water

Parameter
Arsenic (total)
Arsenic (As+3 and dissolved)
pH
Conductivity
TDS
Alkalinity
Hardness
LSI
Turbidity
Temperature (feed only)
TSS
Silica
Calcium
Barium
Fluoride
Iron
Manganese
Sulfate
Chlonde
Chromium
Vanadium
TOC
SDI4

Chlorine (total and free)5


Frequency1
I/day
I/week
I/day
2/day
I/day
I/week
I/week
1 /month
I/week
2/day
I/week
I/week
I/week
I/week
I/week
I/week
I/week
I/week
I/week
I/week
I/week
I/week
1 /month

4/week


Facility
Laboratory
Laboratory
On-site
On-site
Laboratory
On-site
On-site
By Calculation
On-site
On-site
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory
Laboratory

On-site

Standard
Method2


4500-H+ B
2510 B
2540 C



2130 B
2550
2540 D



4500 FC






5310 C
ASTM
D4189-95


EPA
Method3
200.8
200.8









200.7
200.7
200.8

200.7
200.8
300.0
300.0
200.8
200.8





Hach
Method





8221
8226

















8167 (total)
8021 (free)
1 The verification plant was staffed seven days per week.
2 Standard Methods 20th Edition.
^ "IVTptliork for trip Fiptprminfltio-

n of IVTptnls in

Fnvironmpritfll Siarr

mlp^-Sliirvnlpmpr

it T" FPA/finn/i

R-Q4/111 Mnv 1 QQ4
  Available at (NTIS) PB95-125472.
4 SDI was analyzed on the feed water only.
5 Total and free chlorine were monitored prior to the pre-filter and after the first membrane to monitor the chlorine removal.

3.10.1  Experimental Objectives

The objective of this task was to assess the treatment capability of the membrane equipment to
remove arsenic based on water quality conditions at the site.  Mass balances were performed as
part of this task in order to evaluate the concentration of rejected species at the membrane
surface during membrane operation.  Calculation of the recovery limitation caused by limiting
salts was performed to determine the impact of feed water quality  on membrane operation. The
count,  average,  minimum, and maximum values were tabulated for all data sets.  Statistical
analysis (standard deviation and  confidence intervals), were performed on all analytes with eight
                                            27

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or more  discrete  samples  collected  over the verification period.  The median,  minimum,
maximum, and count were presented for each pH data set.

3.10.2 Work Plan

Monitoring  of water quality parameters  in the feed water, permeate  and concentrate water
streams allowed the calculation of percent rejection of the measured parameters  and targeted
inorganic chemical contaminants for the specific operational conditions evaluated.  Estimation of
the percent rejection of arsenic (total) was based upon the equation for solute rejection provided
in the Section 3.3.2, Equation 3.8.

Many of the water quality parameters described in this task were measured on-site by the NSF-
qualified FTO. Analysis of the remaining water quality parameters were performed by MWH
Laboratories, a state certified laboratory.  The methods used for measurement of water quality
parameters are identified in Table 3-6.  A number of the analytical methods utilized in this study
for on-site monitoring of feed, permeate, and concentrate water qualities are further described in
Task  5, Quality  Assurance Project Plan.   These analytical methods include pH, conductivity,
turbidity, alkalinity, hardness, chlorine, and temperature.

For the water quality parameters submitted to MWH Laboratories, water samples were collected
in appropriate containers (containing necessary preservatives as applicable) prepared by MWH
Laboratories.  These samples were then preserved, stored,  shipped,  and analyzed in accordance
with appropriate procedures and holding times.

3.10.3 Analytical Schedule

Feed Water, Permeate and Concentrate Characterization
During  the  testing  period,  the  feed  water,  permeate  and concentrate water  streams  were
characterized at a single set of operating conditions. The water quality monitoring requirements
are provided in Table 3-6.

Water Quality Sample Collection
Water quality data  were collected at the specified intervals during each testing period.   The
monitoring frequency for the water quality parameters is provided in Table 3-6.  To the extent
possible,  analyses for inorganic  water quality parameters were performed on water  sample
aliquots  obtained simultaneously  from the same sampling location, in order to ensure  the
maximum degree of comparability between water quality analytes.

The  TDS concentrations in the feed  water, permeate  and concentrate  streams were used to
calculate the ionic strength of the feed water and concentrate streams, as well as osmotic pressure
gradient across the membrane on a daily basis (see Chapter 4). Osmotic pressure gradient value
was then used for calculation of net driving pressure  and specific flux on a daily basis.  Mass
balances for specified water  quality  parameters [arsenic (total, As+3, and  dissolved),  silica,
fluoride, iron, manganese, chloride, barium, calcium and sulfate] were then calculated once per
week.  Calculation of the potential for recovery limitation based upon limiting salt concentrations
was performed once per week.
                                            28

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3.10.4 Evaluation Criteria and Minimum Reporting Criteria

•      Percent removal of inorganic chemical constituents were developed and the following are
       presented in Chapter 4:
       =>     A temporal plot showing concentrations of target inorganic constituents (arsenic,
              silica,  fluoride, iron, chloride and sulfate) and TDS in the feed water, permeate
              and concentrate  water streams over the  period  of operation  is presented.   A
              temporal plot of the manganese  concentrations was not presented as all results
              (feed water, permeate, and concentrate) were below the minimum reporting limit
              (MRL)of2.0ng/L.
       =>     A table with weekly values of percent removal of target inorganic constituents
              [arsenic  (total,  As+3,  As+5  and  dissolved), silica, fluoride, iron,  manganese,
              chloride,  barium,  calcium  and  sulfate]   and  other  pertinent water quality
              parameters (chromium and vanadium)  for the  period  of operation is presented.
              The equations shown in Section 3.3.2 were used to  determine percent removal of
              all pertinent water quality parameters for verification testing.
       =>     Mass  balances  through the membrane testing system for total arsenic  were
              conducted.  The mass balance equation presented in the Section 3.3.2 was used to
              calculate the mass of inorganic constituents in different water streams.
       =>     Limiting salt concentrations (via solubility product calculation Equation 3.11)
              were calculated  for  specific water quality constituents (CaCCh,  BaSO/t,  and
              CaSO/t)  once  per week.   The  equation for solubility product calculation  as
              presented in Section 3.3.2 (Equation 3.11) were used to compare with standard
              Solubility  Product values to  determine  if the salt concentration is  posing a
              limitation to operational system recovery.
•      Individual water quality and removal goals specified by the  manufacturer:
       =>     Feed,  permeate and concentrate  concentrations of any measured water quality
              parameters are provided in tabular form for the period of operation.
•      Removal of TSS and Turbidity:
       =>     A table of feed, permeate,  and concentrate water measurements are presented for
              TSS during the period  of operation.
       =>     A  table  of feed,  permeate,  and  concentrate water turbidity measurements  are
              presented for the period of operation.

3.11 Task 4:  Data Handling Protocol

The data management system used in the verification testing involved the use of both computer
spreadsheets  and manual  recording  (on-site  logbook)  of  operational  parameters for  the
membrane equipment on  a daily basis. All field activities were thoroughly documented.  Field
documentation included field notebooks, photographs, field data  sheets,  and chain-of-custody
forms. The following guidelines were followed:

•      Field notes were kept in a bound logbook,
•      Field logbook was used to record all water treatment equipment operating data,
•      Each page was sequentially numbered,
•      Each page was labeled with the project name and number,


                                           29

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•      Completed pages were signed and dated by the individual responsible for the entries, and
•      Errors had one line drawn through them and this line was initialed and dated.

All photographs were logged in the  field logbook.   These entries included the time, date, and
subject of the photograph, and identified the photographer.

Original  field  sheets and  chain-of-custody forms accompanied all  samples  shipped to the
analytical laboratory.  Copies of field  sheets  and chain-of-custody forms for all samples are
included in Appendix C.

3.11.1 Experimental Objectives

The objectives of this task were:   1)  to  establish  a viable  structure  for  the recording and
transmission of field testing data such that the FTO provided sufficient and reliable data to NSF
for verification purposes, and 2) to develop a statistical analysis of the data,  as described  in the
document "EPA/NSF  ETV Protocol  for  Equipment Verification Testing  for  Removal  Of
Inorganic Constituents:  Requirements For All  Studies" and "EPA/NSF  ETV  Protocol for
Equipment Verification Testing for Arsenic  Removal:  Requirements For All  Studies."

3.11.2 Work Plan

FTO  operators  recorded data and  calculations by hand in laboratory notebooks.   Daily
measurements were recorded on specially prepared data log sheets as appropriate.  The original
notebooks were stored on-site;  and electronic copies were forwarded to the project manager of
the FTO at least once per week during the testing period.   Operating logs included a description
of the membrane  equipment (description of test  runs, names of visitors,  description of any
problems or  issues, etc.); such  descriptions were  provided in addition  to  experimental
calculations and other items.

A database for the  project was  set  up in the form  of  custom-designed spreadsheets.   The
spreadsheets  were  capable of storing  and manipulating  each monitored  water quality and
operational parameter from each task, each sampling  location, and each sampling time.  All data
from the laboratory notebook and data log sheets were entered into the appropriate spreadsheet.
Data  entry was conducted on-site by  the designated field testing operators.   All recorded
calculations were also checked at this time.  Following data entry, the spreadsheets were printed
out and the printouts were checked against the handwritten data sheet.   Any corrections were
noted on the  hard  copies  and  corrected on the  screen,  and then a corrected version of the
spreadsheet was printed  out.   Each step of the verification process was initialed by the field
testing operator performing the entry or verification step.

Data from MWH Laboratory were received and reviewed by the field-testing operator.  These
data were entered into the data spreadsheets, corrected, and verified in the same manner  as the
field data. As available, electronic data storage and retrieval capabilities were employed in order
to maximize data collection and minimize labor hours required for monitoring.
                                           30

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3.12  Task 5: Quality Assurance Project Plan (QAPP)

QA/QC of the operation of the membrane equipment and the measured water quality parameters
were maintained during verification testing through a quality assurance project plan (QAPP) as
described in this section.

3.12.1 Experimental Objectives

The objective  of  this task was to maintain  strict QA/QC  methods and procedures  during
verification testing. Maintenance of strict QA/QC procedures was important, in that if a question
arose when analyzing or interpreting data  collected for a given experiment, it was possible to
verify  exact conditions at the time of testing.  The elements of the Quality Assurance Project
Plan for the ETV included:

•      Work Plan,
•      Monthly QA/QC Verifications,
•      Data Correctness,
•      Calculation of Indicators of Data Quality, and
•      Corrective Action Plan.

3.12.2 Work Plan

Equipment flow rates were measured and recorded on a daily basis. A routine daily walk through
during testing was  established to verify that each piece of equipment or  instrumentation  was
operating properly.  In-line monitoring equipment such as flow meters, etc. were checked  to
confirm that the readout matches with the actual measurement (i.e. flow rate).

3.12.3 Monthly QA/QC Verifications

The monthly  QA/QC verifications included:

•      Differential  pressure transmitters (verify gauge readings and electrical signal using a
       pressure meter) and
•      Tubing (verify good condition of all tubing and connections; replace  if necessary).

3.12.4 Data Correctness

Data correctness refers to data quality, for which there are five indicators:

•      Representativeness,
•      Statistical Uncertainly,
•      Precision,
•      Accuracy, and
•      Completeness.

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3.12.4.1  Representativeness

As specified by NSF, representativeness of water quality samples for the ETV were ensured by
executing consistent sample collection procedures, including:

•      Sample locations,
•      Timing of sample collection, and
•      Analytical methods, sampling procedures, sample preservation, packaging and transport.

Sample Locations
Sample locations for the Ml5,000 RO Treatment System included the  feed water, permeate
(treated water), and concentrate.  Only one specific sample tap was used at each of these sample
locations.

Timing of Sample Collection
In the RO verification  study, the timing  of sample collection was not  as critical as in, for
example, a granular media filtration verification study in which the filter run time can influence
the  quality of water produced  by the filter.   For the BD verification study, there is  no filter
maturation time, stable period of filter operation, or turbidity breakthrough period.  To the extent
possible, analyses for inorganic  water quality parameters were performed on water sample
aliquots  obtained  simultaneously  from the same sampling location, in  order to ensure  the
maximum degree of comparability between water quality analytes.

Analytical Methods, Sampling Procedures,  Sample Preservation, Packaging and Transport
The  analytical methods and sampling procedures utilized in the verification testing  plan for
collecting laboratory samples and for on-site monitoring of feed water, permeate and concentrate
water quality are described below. Field analyses were performed using portable field analytical
equipment. Laboratory  samples were collected in bottles prepared by MWH Laboratories with
the  appropriate preservative for the analyte.   Once collected,  the samples were  stored in a
refrigerator (4°C) until  ready for transport to MWH Laboratories,  and the  temperature of the
refrigerator were logged daily.  The samples were transported in coolers packed with ice.  With
the  exception of those  samples  noted in Chapter 4, the  samples were  analyzed within the
Standard Methods or EPA recommended holding times, if not analyzed on-site.

Samples  were collected  from lab valves mounted on the panel coming from Vi" ball valves teed
into the permeate line (permeate), 1" bulk fittings mounted on the top of the unit (concentrate),
and a 1"  housing on the  side of the panel (feed water). To the extent possible, analyses for water
quality parameters were performed on water sample aliquots obtained simultaneously  from the
same sampling location, in order to ensure the maximum degree of comparability between water
quality analytes.

       Arsenic (Total)
       Samples were collected headspace free into polyethylene or borosilicate  glass bottles
       provided by the analytical laboratory, capped tightly and  stored refrigerated. The sample
       bottles from the laboratory included the preservative (HNOs) for a holding period of up to
                                           32

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six months.  The samples were analyzed using EPA Method 200.8 within the holding
period of the preserved samples.

Arsenic (As (III) and Dissolved)
Samples were collected on-site and speciated using the procedures (see Appendix B) and
resin  columns  provided  by NSF.   The samples were collected in polyethylene bottles
provided by MWH Laboratories (preserved in accordance with the NSF procedures).
The samples were analyzed using EPA Method 200.8 within the holding period of the
preserved samples (six months).

pH
Analyses for pH were performed  according to Standard Method 4500-H+B.  Samples
were  collected and analyzed on-site immediately and the temperature at which the pH
readings were made was recorded.  Sample agitation and prolonged exposure to air were
avoided. A three-point calibration  of the pH meter used in this study was performed  once
per day when the instrument was in use.  Certified pH buffers (4.0, 7.0, and 10.0) were
used for the daily calibration. The probe was stored in the appropriate solution defined in
the instrument manual.

Conductivity
Analyses for conductivity were  performed according to  Standard Method 2510  B.
Samples were  collected  and  analyzed on-site  immediately.   Sample agitation  and
prolonged exposure to air were avoided.   A three-point calibration of the conductivity
meter used in verification testing was performed once per day when the instrument  is  in
use.  Certified conductivity solutions (184, 1000, and  1990 umoh/cm) and were used.
The probe was stored in the appropriate solution defined in the instrument manual.

Turbidity
Due to the relatively short holding period of 48-hours, these samples were analyzed on-
site using Standard Method 2130  B with a bench-top turbidimeter.  All glassware  used
for turbidity measurements were cleaned  and  handled using lint-free tissues to prevent
scratching.  Sample vials were stored inverted to prevent deposits from  forming on the
bottom surface of the cell.

The bench-top  turbidimeter  was calibrated  within the  expected  range  of  sample
measurements  at the beginning of equipment operation and on  a weekly basis using
primary turbidity standards of 0.1, 0.5, and 5.0 Nephelometric Turbidity Units (NTU).
The turbidity meter has  a  range of 0 to  199 NTU.   Secondary turbidity  standards were
obtained and checked against  the  primary standards.  Secondary standards were used
(4.5, 45.9, and 448 NTU) on a weekly basis to verify calibration of the turbidimeter and
to re-calibrate when more than one turbidity range was used.

The method for  collecting grab  samples was performed  according  to the following
protocol:  1) running a slow, steady stream  from the sample tap,  2)  triple-rinsing a
dedicated sample beaker in this stream, 3) allowing the sample to  flow down the side  of
the beaker to minimize bubble entrainment, 4) double-rinsing the sample vial with the
sample, 5) carefully pouring from the beaker down the side of the  sample vial, 6) wiping
                                    33

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the sample vial clean, 7) inserting the sample vial into the turbidimeter, and 8) recording
the measured turbidity. There were no issues associated with fogging of the glass vials.

Chlorine
Free and total chlorine were analyzed in the feed water (before the pre-filter) and after the
pre-filter to  monitor  for chlorine removal.   There was no sample port between the  pre-
filter and  the first membrane; therefore, chlorine was tested after the first membrane.
Analyses  for both free and  total  chlorine were conducted on-site immediately upon
collection of the samples, using Hach's DPD method of analysis, 8167 for total chlorine
and 8021 for free chlorine (both EPA approved methods).

Alkalinity and Hardness
Alkalinity (bicarbonate) and hardness were not target contaminants for arsenic removal
by RO. Thus, they were measured on-site by properly calibrated  test kits provided by
Hach.  Total alkalinity was measured on-site immediately using Hach's 0.1600 N sulfuric
acid with  Hach's titration method (Hach method 8221) with a detection range of 0 to
5,000 mg/L  as CaCO3.  Total hardness was measured on-site  immediately using Hach's
titration method prepared titrants (EDTA Hach method 8226), with a range of 0 to 25,000
mg/LasCaCO3.

All test kits used on-site were calibrated when the equipment was in use, utilizing known
standards  at  two or more concentration levels.  Data obtained with test kits, which utilize
non-standard methods were not used to determine if the  system met  the  applicable
performance criteria.

Temperature
Readings  for  temperature  were  conducted  on-site  immediately after collection in
accordance with Standard Method 2550.  Raw water temperatures were obtained twice
daily.  The thermometer was  a precision thermometer certified by  the National Institute
of Standards and Technology (NIST).

TDS
Plastic sample bottles were used, as provided by the analytical laboratory.  Analyses were
made as soon as possible due to impracticality of preserving samples, as specified in
Standard Method 2540.  Samples were refrigerated until the time of analysis.

TSS
Plastic sample bottles were used, as provided by the analytical laboratory.  Analyses were
made as soon as possible due to impracticality of preserving samples, as specified in
Standard Method 2540 D.  Samples were refrigerated until the time of analysis.

TOC
Amber glass bottles  preserved with H2SO4 were used,  as  provided by the analytical
laboratory. Analyses were made as soon as possible  according to Standard Method 5310
C.  Samples were refrigerated until the time of analysis, prior to the 28-day holding
period.
                                    34

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Iron
Samples were  collected  headspace free into polyethylene bottles  provided by  the
analytical laboratory, capped tightly and stored refrigerated. The sample bottles from the
laboratory included the preservative (HNCb) for a holding period of up to six months.
All iron samples were analyzed using EPA Method 200.7 within the holding period of the
preserved samples.

Manganese
Samples were  collected  headspace free into polyethylene bottles  provided by  the
analytical laboratory, capped tightly and stored refrigerated. The sample bottles from the
laboratory included the preservative (HNOs) for a holding period of up to six months.
All manganese samples were analyzed using EPA Method 200.8 within the holding
period of the preserved samples.

Sulfate
Samples were  collected  headspace free into polyethylene bottles  provided by  the
analytical laboratory,  capped tightly and stored refrigerated.  All sulfate samples were
analyzed using EPA Method 300.0 within the holding period of the preserved samples.

Chloride
Samples were  collected  headspace free into polyethylene bottles  provided by  the
analytical laboratory, capped tightly and stored refrigerated.  All chloride samples were
analyzed using EPA Method 300.0 within the holding period of the preserved samples.

Silica
Samples were  collected  headspace free into polyethylene bottles  provided by  the
analytical laboratory, capped tightly and stored refrigerated. The sample bottles from the
laboratory included the preservative (HNCb) for a holding period of up to six months.
All silica samples were analyzed using EPA Method 200.7 within the holding period of
the preserved samples.

Chromium
Samples were  collected  headspace free into polyethylene bottles  provided by  the
analytical laboratory, capped tightly and stored refrigerated. The sample bottles from the
laboratory included the preservative (HNOs) for a holding period of up to six months.
All chromium samples were analyzed using EPA Method 200.8 within the holding period
of the preserved samples.

Fluoride
Samples were  collected  headspace free into polyethylene bottles  provided by  the
analytical laboratory, capped tightly and stored refrigerated.  All fluoride samples were
analyzed using  Standard Method 4500 FC  within the holding  period  of the preserved
samples (28 days).

Vanadium
Samples were  collected  headspace free into polyethylene bottles  provided by  the
analytical laboratory, capped tightly and stored refrigerated. The sample bottles from the
                                    35

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       laboratory included the preservative (HNCb) for a holding period of up to six months.
       All vanadium samples were analyzed using EPA Method 200.8 within the holding period
       of the preserved samples.

       Barium
       Samples  were  collected  headspace  free  into  polyethylene  bottles provided  by the
       analytical laboratory, capped tightly and stored refrigerated. The sample  bottles from the
       laboratory included the preservative (HNOs) for a holding period of up to six months.
       All barium samples were analyzed using EPA Method 200.8 within the holding period of
       the preserved samples.

       Calcium
       Samples  were  collected  headspace  free  into  polyethylene  bottles provided  by the
       analytical laboratory, capped tightly and stored refrigerated. The sample bottles from the
       laboratory included the preservative (HNOs) for a holding period of up to six months.
       All calcium  samples were analyzed using EPA Method 200.7 within the holding period
       of the preserved samples.

       SDI
       Sample water was collected in a 5-gallon polyethylene cube-container, headspace free
       and shipped  overnight to the laboratory for analysis.  The American Society  of Testing
       and Materials  (ASTM) test number 4189-95 procedures  were  followed for the SDI
       calculation.

       Representativeness of Operational Parameters
       As specified by NSF, representativeness for operational parameters entails collecting a
       sufficient quantity  of data during operation to be able to detect a change in operations.
       As specified by NSF, detecting a ±10%  change  in an operating parameter, such  as
       pressure, is sufficient.  Operational parameters including flow and  pressure were recorded
       twice per day, which NSF specifies as sufficient for tracking changes in operational
       conditions that exceed this 10% range.

       Flow Rates
       The permeate and concentrate flow rates were verified daily using a calibrated container
       and stopwatch method to manually verify  the flow rates from the system.   While  no
       adjustments  to the  panel mounted flow meters was possible, the  manual "check" could
       verify if the panel mounted flow meters were accurate.

3.12.4.2  Statistical Uncertainty

Statistical uncertainty  of  the water  quality  parameters  analyzed  were evaluated  through
calculation of the 95% confidence interval around the sample mean for parameters with  eight or
more samples. Description of the confidence interval calculation is provided in Section 3.12.5.
                                           36

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3.12.4.3 Methodology for Measurement of Precision and Accuracy

Precision and Accuracy for Water Quality Parameters
Tables 3-7 and 3-8  summarize the methodology used in the ETV for  the measurement of
precision and accuracy for each water quality analysis performed for the verification study.
Arsenic speciation columns were QA/QC checked by NSF and were provided by NSF for the
verification testing. The sampling location for each duplicate sample was alternated between the
feed water, permeate, and concentrate.

Precision and Accuracy for Operational Parameters
The operational parameters in the ETV included flow rates and pressures. Water flow rates were
verified for all  flow  meters  (located on the permeate  and concentrate lines) daily by using a
calibrated container and a stopwatch.   The duration of the  bucket tests  were one minute or
longer, depending on  the magnitude of the flow rate.

Spiked Samples
Spiked samples were utilized at MWH laboratory,  as presented in Table 3-8.  Spiked samples
were applicable for the analyses performed on-site at the treatment system at a 10% frequency,
as presented in Table  3-9.

 Table 3-7: Methodology for Measurement of Precision and Accuracy
Parameter
Arsenic (Total)
(report to nearest 1
Mg/L)
pH
(report to nearest 0. 1
pH unit)

Silica
(report to nearest 0. 1
mg/L)
Fluoride
(report to nearest 0. 1
mg/L)
Chromium
(report to nearest 1
Mg/L)
Vanadium
(report to nearest 1
Mg/L)
TOC
(report to nearest 0.5
mg/L)
Chloride
(report to nearest 1
mg/L)
MRL
l.Ong/L


0-14pH
units


0.05 mg/L


0. 1 mg/L


2 Mg/L


10 pg/L


0.5 mg/L


1 mg/L


On-site Duplicate
Frequency
Seven measurements per
week in duplicate (33% of
samples)
Seven measurements per
week in duplicate (33% of
samples)

One sample per week in
duplicate (33% of samples)

One sample per week in
duplicate (33% of samples)

One sample per week in
duplicate (33% of samples)

One sample per week in
duplicate (33% of samples)

One sample per week in
duplicate (33% of samples)

One sample per week in
duplicate (33% of samples)

Acceptable
Precision
30%


10%2



30%


20%


30%


30%


30%


20%


Accuracy
See procedures of MWH
Laboratory (see Table 3-8)

Daily 3-point calibration
with certified pH buffers in
range of measurements
(4.0, 7.0 and 10.0)
See procedures of MWH
Laboratory
(see Table 3 -8)
See procedures of MWH
Laboratory
(see Table 3 -8)
See procedures of MWH
Laboratory
(see Table 3 -8)
See procedures of MWH
Laboratory
(see Table 3 -8)
See procedures of MWH
Laboratory
(see Table 3 -8)
See procedures of MWH
Laboratory
(see Table 3 -8)
                                           37

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Table 3-7:  Methodology for Measurement of Precision and Accuracy (continued)
    Parameter
  MRL
On-site Duplicate
   Frequency
Acceptable
 Precision
Accuracy
Iron
(report to nearest 0.5
mg/L)
Manganese
(report to nearest 0.5
mg/L)
Sulfate
(report to nearest 1
mg/L)
Temperature
(report to nearest
0.1°C)
Alkalinity
(report to nearest 1
mg/L as CaCO,)

Hardness
(report to nearest 1
mg/L as CaCO,)

Turbidity
(report to nearest
0.05 mg/L)
Conductivity
(report to nearest 0.1
l_imho/cm)

Barium
(report to nearest 0.5
mg/L)
Calcium
(report to nearest 0.5
mg/L)
TSS
(report to nearest 1
mg/L)
SDI
(report to nearest 1
mg/L)
TDS
(report to nearest 1
mg/L)	
 0.5 mg/L    One sample per week in
             duplicate (33% of samples)

0.015 mg/L   One sample per week in
             duplicate (33% of samples)

  2 mg/L     One sample per week in
             duplicate (33% of samples)

    NA       Two measurements per
             week in duplicate (20% of
             samples)
  10 mg/L    One sample per week in
             duplicate (33% of samples)
 10 mg/L    One sample per week in
             duplicate (33% of samples)
 0.05NTU    One sample per week in
             duplicate (33% of samples)
4 |imho/cm   Eight samples per week in
             duplicate (20% of samples)
  2 (ig/L     One sample per week in
             duplicate (33% of samples)

  1  mg/L     One sample per week in
             duplicate (33% of samples)

  4  mg/L     One sample per week in
             duplicate (33% of samples)

     1        One sample per month in
             duplicate (100% of samples)
 10 mg/L    Four samples per week in
             duplicate (20% of samples)
                          30%      See procedures of MWH
                                    Laboratory
                                    (see Table 3-8)
                          30%      See procedures of MWH
                                    Laboratory
                                    (see Table 3-8)
                          20%      See procedures of MWH
                                    Laboratory
                                    (see Table 3-8)
                          10%3      Initial and weekly
                                    verification against a NIST
                                    thermometer.
                          30%      Weekly calibration
                                    verification using known
                                    standards at two
                                    concentration levels
                          30%      Weekly calibration
                                    verification using known
                                    standards at two
                                    concentration levels
                          30%3      Initial and weekly
                                    calibration with primary
                                    standards. Daily
                                    calibration verification
                                    with secondary standards.
                          10%      Daily calibration
                                    verification using known
                                    standards at three
                                    concentration levels
                          30%      See procedures of MWH
                                    Laboratory
                                    (see Table 3-8)
                          30%      See procedures of MWH
                                    Laboratory
                                    (see Table 3-8)
                          30%      See procedures of MWH
                                    Laboratory
                                    (see Table 3 -8)
                          30%      Use procedures of the
                                    American Society of
                                    Testing and Materials
                                    (ASTM) test number
                                    4189-95.
                          30%      See procedures of MWH
                                    Laboratory
                         	(see Table 3-8)	
                                                38

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   Table 3-7: Methodology for Measurement of Precision and Accuracy (continued)
       Parameter
  MRL
On-site Duplicate
   Frequency
Acceptable
 Precision
Accuracy
   Chlorine
   (report to nearest 0.1
   mg/L)
0.02 mg/L   Four samples per week in
            duplicate (25% of samples)
                          30%      Use Hach 8167 (total) and
                                    Hach8021 (free)
                                    procedures for accuracy
                                    using Hach standard
                                    solutions.
   As  and dissolved arsenic  samples were prepared on-site using arsenic speciation procedures developed by
   Battelle for the EPA (see Appendix B).  The laboratory method used to measure the arsenic is EPA 200.8, and
   will measure total arsenic (after on-site preparation).
   "Daily" refers to each day the verification plant is staffed (7 days a week).
   For all  on-site duplicate analyses, the first analysis is considered the  sample and that result is reported.  The
   duplicate analysis is used for calculating precision per  Section 6.3.4 in Chapter 1 of the EPA/NSF ETVProtocol
   for Equipment Verification Testing for Arsenic Removal (EPA/NSF, 2003).
Table 3-8:  Laboratory Water Quality Analyses Indicators
Parameter
Arsenic
(Total)


TDS
TSS
Silica
Fluoride
Iron
Manganese
Sulfate
Chloride
Chromium
Vanadium
Barium
Calcium
TOC


Laboratory
Fortified
Matrix
(LFM),
i.e. spike
sample
10%
(1 per 10
samples)

10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%


LFM
Duplicate
10%



10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%
10%


LFM
Acceptance
Limits
(%
Recovery)
+30



< 5% RPD
< 20% RPD
+30
+20
+30
+30
+20
+20
+30
+30
+30
+30
+10


Method
Blank
(MB)
5%
(1 per 20
samples or
less)
5%
5%
5%
5%
5%
5%
10%
10%
5%
5%
5%
5%
run after
each
sample
MB
Acceptance
Limits
< MRL1



< MRL1
< MRL1
< MRL1
< MRL1
< MRL1
< MRL1

-------
 Table 3-9:  On-Site Water Quality Analyses Indicators

                                                                     Acceptable Accuracy
 On-Site Parameters	On-site Spike Frequency	(% Recovery)	
 Alkalinity                                10%                                + 30
 Hardness                                10%                                + 30
 Chlorine                                 10%                                + 30
 Turbidity                                NA1                                NA1
 pH                                      NA1                                NA1
 Temperature                              NA                                NA
 Conductivity	NA1	NA1	
  Accuracy documented by proper instrument setup and calibration with buffers or standards.
  Accuracy established by using a NIST traceable thermometer on a weekly basis.

Method Blanks
The methodology for use  of method blanks is summarized in Table  3-10. Field blanks were
submitted with each set of samples submitted to MWH Laboratories.  One  field blank was
collected for each parameter submitted for analysis.


 Table 3-10: Methodology for Use of Method Blanks

	Method	Methodology for Blanks	
 Arsenic                          Blanks  were  used in   accordance with  the  procedures  of  MWH
                                  Laboratory:.
 pH                              Purchased certified pH buffers; no use of blanks.
 Temperature                       No use of blanks.
 Alkalinity                        Purchased  reagent-grade ultra-pure water  and  kept  in  stock  at the
                                  verification plant for use as a blank on a weekly basis to verify proper
                                  operation of the instrument.
 Total Hardness                    Purchased  reagent-grade ultra-pure water  and  kept  in  stock  at the
                                  verification plant for use as a blank on a weekly basis to verify proper
                                  operation of the instrument.
 Turbidity                         Purchased  reagent-grade ultra-pure water  and  kept  in  stock  at the
                                  verification plant for use as  a blank on a daily basis to verify proper
                                  operation of the instrument.
 Conductivity                      No use of blanks.
 TDS                             Blanks  were  used in   accordance  with  the procedures  of  MWH
                                  Laboratory:.
 Other Inorganics                   Blanks  were  used in   accordance  with  the procedures  of  MWH
	Laboratory'.	
1  See Table 3-8.

Proficiency Testing Samples
Proficiency Testing (PT) samples were analyzed in accordance with the  procedures of the  MWH
Laboratory, which  performed all  laboratory analyses.  External PT samples  (single blind) were
analyzed approximately twice  a  year for each  analysis  for which National Environmental
Laboratory Accreditation Conference (NELAC) requires PT samples. Additionally, a laboratory
control sample (typically second source) is analyzed with each analytical batch.
                                               40

-------
3.12.4.4 Completeness

Completeness refers to the number of valid, acceptable samples collected from a measurement
process compared to the number of samples  expected  to  be obtained.   The  completeness
objective for data generated during this verification test is based on the number of samples
collected  and  analyzed  for  each  parameter  and/or  method.   Table  3-11  illustrates  the
completeness objectives  for  performance  parameter and/or  method  based on the sample
frequency:

        Table 3-11: Completeness Objectives Based on Sample Frequency

                 Number of Samples Per Parameter
                         and/or Method                      Percent Completeness
                             (MO                                  80%
                             11-50                                 90%
       	>50	95%	

3.12.5 Calculation of Indictors of Data Quality

Statistical Uncertainty
For the water quality parameters monitored, 95% confidence intervals were  calculated for data
sets  of eight values  or  more.   The  following equation was used for  confidence  interval
calculation:

          Confidence Interval =  x± [Vi,i -(a/2) x (SA/n)]

where:    x = sample mean
          S  = sample standard deviation
          n  = number of independent measurements included in the data set
          t  = Student's t distribution value with n-1 degrees  of freedom
          a = significance level, defined for 95% confidence  as:  1 - 0.95 = 0.05

According to the 95% confidence interval approach, the a term is defined to have the value of
0.05, thus simplifying the equation for the 95% confidence interval in the following manner:

          95% Confidence Interval = x + [In-1,0.975 x (SA/n)]

Calculation of Precision
As  specified in Standard Methods  (Method 1030  C),  precision is  specified by the standard
deviation of the results of replicate analyses.  The overall precision of a  study includes the
random errors involved in sampling as well as the errors in sample preparation and analysis.

                                           n
          Precision = Standard Deviation = V[Z (x"z - x)2 -^ (n - 1)]
                                          /=!

where:    x =  sample mean
          X; =  Ah data point in the data set
                                           41

-------
          n  = number of data points in the data set

Precision refers to the degree of mutual agreement among individual measurements and provides
an estimate of random error.   Analytical  precision  is  a measure of how far  an individual
measurement may be from the mean of replicate  measurements.   The standard  deviation  and
relative standard deviation recorded from sample analyses were recorded as a means to quantify
sample precision.  The percent relative standard deviation was calculated in the verification study
in the following manner:

          %Relative Standard Deviation = S(100)/Xaverage

where     S = Standard Deviation
          Xaverage=  the arithmetic mean of the recovery values

Calculation of Accuracy
Accuracy is quantified  as the percent recovery of a parameter in a sample to which a  known
quantity of that parameter was added.

          Accuracy = Percent Recovery = 100 x [1- (Xknown - X

where     Xknown = known concentration of measured parameter
                  = measured concentration of parameter
Calculation of Completeness
Completeness is defined as the following for all measurements:

          %C = (V/T)X100

where:    %C = percent completeness
          V = number of measurements judged valid
          T = total number of measurements

3.12.6 Corrective Action Plan

The corrective action plan for water quality parameters is summarized in Table 3-12.
                                          42

-------
  Table 3-12:  Corrective Action Plan
      Parameter
    Acceptance Criteria
Sequence of Steps for Corrective Action
  Any Duplicate
  Analysis

  Any Method Blank
  Any Performance
  Evaluation (PE) or
  Proficiency Sample
  pH
  Temperature

  Turbidity
  (Bench-top)
  Alkalinity,
  Total Hardness,
  Calcium Hardness,
  TDS
See Table 3-7
See Table 3-8; criteria set by   •
MWH Laboratory

Within recovery specified for   •
each PE or proficiency
sample                     •
<1 0% difference from         •
previous day                •
<20% difference from
previous day
No increasing or decreasing
trend indicated by results of
proficiency samples
<20% difference from
previous reading
Re-sample duplicates
Check   instrument  calibration;  re-calibrate
instrument
See Table 3-8; perform procedures specific to
each  analysis   as  determined  by   MWH
Laboratory
Check and verify all steps in sample collection
and analysis
Re-do PE or proficiency sampling and analysis
Check for change in feed water source or supply
Check instrument calibration
Re-calibrate instrument
Check for change in feed water source or supply
Check/verify system operating conditions
Verify  turbidimeter  operation  and  status
sample tap
Perform   routine   maintenance/cleaning
instrument
Verify calibration using secondary standards
Re-calibrate using primary standards
Verify change in feed water source or supply
of
                                                                                             of
3.13  Operation and Maintenance

The following sections provide  O&M  criteria that  were  necessary for a  safe  and successful
operation of the M-15,000 RO Treatment System.

3.13.1  Operation

Start-Up Procedures
The start-up sequence, as provided by the manufacturer, for the M-15,000 RO Treatment System
is:

1.      Ensure power switch (located on top of control box) is in the off position.
2.      Plug the unit into an appropriate power supply.
3.      If installing a pressure tank system, open the ball valve on the bulkhead.
4.      Turn the blending valve to coldest setting [90°].
5.      Fully open the concentrate needle valve by turning it counter clockwise.
6.      Fully close recirculate needle valve by turning it clockwise.
7.      Turn the incoming water supply on the RO processor to the "on" position.
        •      The water inlet solenoid valve will open.
        •      There is a 5-second delay before the pump starts.
                                               43

-------
       •     The system will cycle  on and off automatically during initial start up as air is
             purged from system.
       •     Allow the unit to  run  for  five minutes while  excess  air is being  purged  from
             system.
8.      Close the concentrate needle valve until the feed pressure gauge reaches a max. of 150
       psig.
9.      Open the recirculation needle valve until the unit feed pressure gauge drops to 140 psig.
10.    Close the concentrate needle  valve until  150 psig is again achieved on the pump feed
       pressure gauge.

Shut Down Procedures
1.      Turn incoming feed water off while unit is running.
2.      System will automatically turn off due to lack of feed water pressure.
3.      Turn power switch to the OFF position.

3.13.2 Maintenance

Quarterly maintenance for  the Ml5,000 RO Treatment System requires replacement of the
cartridge sediment pre-filter and RO module O-rings.

Pre-filter Replacement Procedure
1.      Turn incoming feed water off while unit is running.
2.      System will automatically turn off due to lack of feed water pressure.
3.      Turn power switch to the OFF position.
4.      Close ball valve on permeate line connection on bulkhead
5.      Unplug unit from power supply.
6.      Place bucket under pre-filter to catch the water from the filter housing.
7.      Using supplied filter wrench, loosen filter housing.
8.      Replace with new 20-micron  sediment filter and replace filter housing using wrench to
       tighten securely, (o-rings and  bowls  need  to be lubricated with a water-soluble lubricant
       such as KY jelly).
9.      Follow "start-up procedure".

Maintenance requires the replacement  of the RO membrane  modules based on efficiencies of
TDS reduction per module.   To simulate this procedure, two  of the six membranes were replaced
during the simulated maintenance procedures performed at the end of the testing period.

Module Replacement Procedure
1.      Replace RO  membrane by loosening retaining clamp at top of stainless steel membrane
       vessel.
2.      Carefully pry loose PVC end cap from stainless steel vessel.
3.      Pull membrane from vessel using pliers if necessary and discard.
4.      Take note of location of black BRINE SEAL located  approximately 1/2" from one end of
       membrane, so the new membrane is installed in the proper direction.
5.      Lubricate O-Rings on both  ends of the membrane  and PVC vessel cap with KY Jelly or
       other water-soluble lubricant.  Vaseline or other petroleum-based lubricants will damage
       rubber o-ring and cause leaks.
                                           44

-------
6.      Insert new membrane into vessel with the brine seal on same position as the old one just
       removed. Replace PVC end cap and tighten clamp evenly.
7.      Follow "start-up procedure".

3.13.3 Operability

During verification testing, attention was given to equipment operability aspects.  Among the
factors that were considered were:

•      Fluctuation of flow rates and pressures through membrane unit  —  the time interval  at
       which resetting is needed (i.e., how long can feed pumps hold on  a set value for the feed
       rate?)
•      Was there a device present to aid the operator with flow control adjustment?
•      Was a continuous particle counter provided for monitoring of membrane permeate?
•      Was a continuous conductivity meter provided for monitoring of membrane permeate?
•      Was transmembrane pressure measurement provided?
•      Was feed water recovery provided?
•      Was recycle flow rate provided?
•      Was rate of flow of raw water measured?

This report addresses  the above questions. The  issues of operability were dealt  with in the
portion of the reports that are written in response to Tasks 1 & 2 of the verification testing plan
and may be found in Chapter 4.
                                           45

-------
                                       Chapter 4
                                 Results and Discussion
4.1 Introduction
The verification testing of the M-15,000 RO Treatment System performed at the CVWD Well
7802 in Thermal,  California, commenced on April 26, 2004, and concluded on May 26, 2004.
The  system ran  continuously with the exception of two brief system shut downs, and one
extended shut down period of approximately four days. The shut downs occurred on April 29,
May 3-6, and on May 13, 2004. In total, the system was in operation for 27 days.

Quarterly and a portion of annual (replacement of two RO membranes) O&M procedures were
performed after completion of the verification testing,  on May 26, 2004.  Results and discussion
of the membrane operation, cleaning efficiency (substituted by  quarterly/annual O&M), finished
water quality, and data management are presented in this chapter as the following five tasks:

Task 1:  Membrane Operation
Task 2:  Cleaning Efficiency
Task 3:  Feed water and Treated Water Quality Monitoring
Task 4:  Data Handling Protocol
Task 5:  Quality Assurance Project Plan (QAPP)

The field data (operational and water quality) was maintained in a field logbook per Section 3.11
(Task 4) and may be found in Appendix C.  The corresponding off-site laboratory data  may be
found in Appendix D.

4.2 Task 1: Membrane Operation

The objective of this task was to  evaluate the M-15,000 RO Treatment System operation, not to
optimize the system.  System performance was evaluated relative to the  stated raw water quality
ranges specified by the manufacturer in Chapter 3 (Table 3-2).  For verification testing purposes,
the equipment was operated for 27 days. During the testing period the  membrane productivity,
rate of specific flux decline, and rejection capabilities were evaluated.

The objectives of Task 1 were to:

•     Evaluate the operational conditions for the membrane  equipment relative to the stated
      water quality goals,
•     Determine the feed water recovery achieved  by the membrane equipment under the
      operational conditions evaluated during the one month verification period,  and
•     Determine the rate of specific flux decline observed over the testing period.

The following evaluation and reporting criteria for Task 1 enabled the objectives to be met:

•     General operational performance,
•     Power consumption,
                                          46

-------
•      Consumables and waste generation, and
•      Concentrate stream characterization.

4.2.1   General Operational Performance

The purpose of this test was to evaluate the general operational performance of the M-15,000 RO
Treatment System.   Operational information  regarding this task was  collected throughout the
length of the verification testing according to the frequency presented in Chapter 3 (see Table 3-
5).  Specifically, the following operational parameters were monitored:

•      Feed water, permeate, concentrate, and recycle flow rates,
•      Membrane element inlet and feed water pressures,
•      Discharge tank pressure (permeate line) and back pressure (concentrate line),
•      Water recovery and recycle ratio,
•      Feed water temperature,
•      Specific flux (flux and temperature-corrected specific flux),
•      Net driving pressure,  and
•      Osmotic pressure gradient.

4.2.1.1 Feed Water, Permeate, Concentrate, and Recycle Flow Rates

The  M-15,000 RO Treatment System was  equipped with panel  mounted flow meters to  read
permeate and concentrate flow rates and to make adjustments as necessary.  The feed water  flow
rate was recorded as the sum of the permeate and the concentrate flow rates.  The recycle flow
rate was  documented from a digital  flow meter installed on the recycle line prior to the  feed
water line. Each of these four flow streams  (feed water, permeate, concentrate, and recycle - see
Figure 2-2 in Section 2.1) was monitored twice per day during the verification testing. This data
is  graphically  presented in  Figure 4-1  with the corresponding  data  presented  in  Table  4-1.
Included  in this table are the average, minimum, maximum, count, standard deviation,  and  95%
confidence interval data calculated for each of the flow streams.  Since there were two different
types of pre-filters used during the study (carbon bloc and  sediment), Table  4-1 has been
subdivided into two sections, each representing the type of pre-filter used during the verification
test.

The vertical lines in  Figure 4-1 represent each time the pre-filter was changed and the break in
the data represents  the four days the system was down (May 3-6)  due to operational issues.  The
feed water flow rate between April 26, 2004 and May 13, 2004 continued to decrease.  Steps to
recover the feed flow rate included  changing out  the  carbon  bloc  pre-filter, which served  to
temporarily improve the feed flow rate. Once it was discovered that the periodic operation of the
CVWD Well 7802 introduced a slug of solids with each start-up (approximately every three
days), the carbon bloc pre-filter was replaced with a sediment pre-filter on May 13, 2004. After
this modification to the system,  a relatively constant feed flow rate (25 gpm on average)  was
achieved.  The initial decreasing feed water flow rates (approximately  20 gpm decreasing to  17
gpm with the carbon bloc pre-filter)  led to varied  flow rates in the concentrate,  permeate and
recycle  flows,  which were also stabilized after replacing the  carbon  bloc pre-filter with a
sediment pre-filter.  While the carbon bloc pre-filter was originally determined necessary due to
                                           47

-------
the chlorine levels in the feed water, the operational issues caused by the pre-filter clogging led
the manufacturer to recommend the use a sediment pre-filter in place of the carbon bloc and risk
damage to the membranes due to exposure to chlorine for the remaining limited ETV operation
period.  The system ran continuously for 27 of the 31-day verification testing period.  For one
four-day period, the system was  shut down due to operational issues. Clogging  of the carbon
bloc pre-filter is believed to be the cause of the shut down. Ideally at this test sight, the vendor
has indicated that a separate granular activated carbon tank would be used to remove the chlorine
prior to the M-15,000 RO Treatment System.  The pre-filter on the M-15,000 RO  Treatment
System would then consist of a sediment filter to further reduce the  amount of particulates prior
to the water entering the RO.
                      Carbon Block
                      Pre-Filter Changed
                                                    Carbon Block Pre-
                                                   • Filter Replaced
                                                    with Sediment Pre
                - Feed Water
                • Permeate
                • Recycled Water
                • Concentrate
                             o
                             jo
o
^H

-------
Table 4-1:  Feed Water, Permeate, Concentrate and Recycle Flow Rates
Carbon Bloc
Pre-filter
Date
4/26/04
4/27/04
4/28/04
4/29/04

4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04 (before)
Average
Minimum
Maximum
Number of
C 1
Samples
Standard Dev.
95% Confidence
Interval
Sediment Pre-
fllter
5/13/04 (after)
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of
Samples
Standard Dev.
95% Confidence
Interval


AM
20.50
19.50
19.00
18.00
B2: 13.00
A2:1700
17.00
16.75
23.00
23.25
22.00
21.50
19.75
19.00
17.75
19.57
16.75
23.25

14

2.21
(18.08,
21.07)


25.50
25.25
25.00
25.50
26.00
26.50
25.00
25.00
25.00
24.50
24.50
24.50
25.00
24.75
25.14
24.50
26.50
14

0.58
(24.75,
25.53)
Feed Water
(gpm)1
PM
19.50
19.50
18.50
16.00
B: 16.50
A17.50
17.00
16.50
23.25
23.00
22.00
21.50
19.50
18.50
NA
19.40
16.00
25.25

13

2.41
(17.69,
21.12)
Feed Water
(gpm)
25.50
25.25
25.00
25.50
26.00
26.00
25.00
25.25
25.00
24.50
24.50
24.50
24.75
24.75
25.11
24.50
26.00
14

0.51
(24.76,
25.45)


Ave
20.00
19.50
18.75
17.00
AM 15.00
IM 17.00
17.00
16.63
23.13
23.13
22.00
21.50
19.63
18.75
17.75
19.43
16.63
23.13

14

2 27
(17.89,
20.96)


25.50
25.25
25.00
25.50
26.00
26.25
25.00
25.13
25.00
24.50
24.50
24.50
24.88
24.75
25.13
24.50
26.25
14

0.54
(24.76,
25.49)


AM
14.00
13.50
13.00
12.80
B:11.00
A: 9.50
8.50
8.25
11.50
11.50
11.00
10.75
10.00
9.50
9.25
10.93
8.25
14.00

14

1.87
(9.67,
12.20)


13.00
12.75
12.50
13.00
13.00
13.00
12.50
12.50
12.25
12.00
12.00
12.00
12.00
12.25
12.48
12.00
13.00
14

0.41
(12.20,
12.76)
Permeate
(gpm)
PM
13.50
13.50
12.50
14.00
B:9.00
A 9.00
8.50
8.25
11.50
11.25
11.00
10.75
10.00
9.50
NA
11.02
8.25
14.00

13

1.94
(9.64,
12.40)
Permeate
(gpm)
13.00
12.75
12.50
13.00
12.50
13.00
12.50
12.50
12.25
12.00
12.00
12.00
12.00
12.25
12.45
12.00
13.00
14

0.38
(12.19,
12.71)


Ave
13.75
13.50
12.75
13.40
AM 1025
IM9.00
8.50
8.25
11.50
11.38
11.00
10.75
10.00
9.50
9.25
10.91
8.25
13.75

14

1.88
(9.64,
12.19)


13.00
12.75
12.50
13.00
12.75
13.00
12.50
12.50
12.25
12.00
12.00
12.00
12.00
12.25
12.46
12.00
13.00
14

0.39
(12.20,
12.73)
Concentrate
(gpm)
AM PM
6.50 6.00
6.00 6.00
6.00 6.00
5.20 2.00
B:2.00 B:7.50
A: 8.50 A 8.50
8.50 8.50
8.50 8.25
11.50 11.75
11.75 11.75
11.00 11.00
10.75 10.75
9.75 9.50
9.50 9.00
8.50 NA
8.71 8.38
5.20 2.00
11.75 11.75

14 13

2.15 2.81
(7.25, (6.39,
10.17) 10.38)

Ave
6.25
6.00
6.00
3.60
AM 525
IM8.00
8.50
8.38
11.63
11.75
11.00
10.75
9.63
9.25
8.50
8.55
3.60
11.75

14

2.40
(6.93,
10.18)
Concentrate
(gpm)
12.50 12.50
12.50 12.50
12.50 12.50
12.50 12.50
13.00 13.50
13.50 13.00
12.50 12.50
12.50 12.75
12.75 12.75
12.50 12.50
12.50 12.50
12.50 12.50
13.00 12.75
12.50 12.50
12.66 12.66
12.50 12.50
13.50 13.50
14 14

0.30 0.29
(12.45, (12.47,
12.87) 12.86)

12.50
12.50
12.50
12.50
13.25
13.25
12.50
12.63
12.75
12.50
12.50
12.50
12.88
12.50
12.66
12.50
13.25
14

0.27
(12.47,
12.85)


AM
8.53
9.00
9.14
10.16
B: 12.84
A 8.90
9.65
9.84
6.30
6.94
7.80
8.05
9.42
9.70
10.68
8.87
6.30
10.68

14

1.24
(8.03,
9.70)


5.27
5.75
5.35
5.19
4.88
4.58
5.24
5.38
5.37
5.48
5.30
5.39
5.16
5.36
5.26
4.58
5.75
14

0.27
(5.08,
5.45)
Recycle
(gpm)
PM
8.85
9.07
8.34
11.96
B: 9.91
A 9.56
9.72
9.89
6.76
6.95
7.89
8.06
9.43
9.85
NA
8.95
6.76
11.96

13

1.39
(7.96,
9.93)
Recycle
(gpm)
5.31
5.81
5.37
5.21
4.62
5.14
5.27
5.19
5.45
5.48
5.29
5.46
5.21
5.34
5.30
4.62
5.81
14

0.26
(5.12,
5.47)


Ave
8.69
9.04
8.74
11.06
AM 10X7
IM9.74
9.69
9.87
6.53
6.95
7.85
8.06
9.43
9.78
10.68
8.97
6.53
11.06

14

1.30
(8.09,
9.85)


5.29
5.78
5.36
5.20
4.75
4.86
5.26
5.29
5.41
5.48
5.30
5.43
5.19
5.35
5.28
4.75
5.78
14

0.25
(5.11,
5.45)
 Feed water flow rates are calculated values and are the sum of the permeate and concentrate flow rates.
2 B= Before and A= After manual adjustments made to system.
Note: Only the 'after' values and averages on April 30,2004 are used in the statistical calculations.
AM = First sample daily collection.
PM = Second sample daily collection.
NA = Not Applicable.
                                                          49

-------
4.2.1.2  Membrane Element Inlet and Feed Water Pressures

Pressure gauges were panel mounted for the inlet (feed water plus recycled water) pressure, back
pressure (pressure on the  concentrate line), and tank pressure  (pressure on the permeate  line
which was open to drain for the purpose of this testing).  The feed water  pressure gauge  was
installed on the feed water line between the raw (chlorinated groundwater)  line and the inlet to
the M-15,000  RO Treatment System.   Pressure was monitored and  recorded twice daily
[morning  (AM) and  evening  (PM)],  with the average daily (AM and PM) data presented in
Figure 4-2 and the corresponding data presented in Table 4-2.   Additionally, Table 4-2 presents
the pressure data as two data sets, with the carbon bloc pre-filter and with the sediment pre-filter,
to evaluate the operational impact (with regard to pressure) of using different types of pre-filters.
Throughout the verification test, there  was a limited amount  of variability in the feed water
pressure, ranging from 78 to 85 psi.  There was, however, a larger range of pressure readings on
the inlet pressure (ranging from 102 to 150 psi), believed to be related to clogging of the carbon-
bloc pre-filter (discussed in additional detail in Section 4.2.1.1).  While the carbon bloc pre-filter
was in  place, the inlet pressure ranged  from 102 to 147 psi.   Once the sediment pre-filter
replaced the carbon bloc pre-filter, the inlet pressure ranged from 140 to  150  psi.

In addition to monitoring the feed water and inlet pressures, the back pressure (concentrate line)
and the tank pressure (permeate line) were monitored twice daily for use in  calculating the daily
net driving pressure.  During the verification  test,  both  the  permeate and concentrate lines
discharged to a drain under atmospheric conditions.  The recorded back pressures  ranged from
18 to  75 psi, and the tank pressures ranged from 0 to 7 psi. There was large variability in the
back  pressure while the  carbon bloc pre-filter was in use (i.e.  prior to May 13, 2004) with a
steady back pressure realized once the sediment pre-filter was in use.
                                            50

-------
160
                        Carbon Block
                        Pre-Filter Changed
D-D-Ovcr^^D-H^c^^
                                               Carbon Block Pre-Filter
                                               Replaced with Sediment
                                               Pre-Filter
                                                                              -O- Inlet Water

                                                                              —•— Feed Water

                                                                              —O— Permeate
                                                                               • Concentrate
                           Verification Testing Date
 Figure 4-2: Average daily feed water, inlet, back pressure, and tank pressures.
                                            51

-------
Table 4-2:
Carbon
Bloc Pre-
fllter
Date
4/26/04
4/27/04
4/28/04
4/29/04

4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
(before)
Average
Minimum
Maximum
Number of

Samples
Standard

Deviation
95%
Confidence
Interval
Sediment
Pre-filter
5/13/04
(after)
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of

Samples
Stand. Dev.
95%
Confidence
Interval
Feed Water, Inlet, Back Pressure, and Tank Pressures
Feed Water Inlet Back Pressure,
Pressure (psi) Pressure (psi) Concentrate Line psi)

AM
85
82
80
84
B':85
A1: 82
85
84
82
80
84
85
85
85
85

83
80
85

14


2

(82,
85)


PM
82
82
82
85
B: 85
A: 85
85
85
80
80
82
84
85
85
NA

83
80
85

13


2

(82,
85)


Ave
84
82
81
85
AM: 84
PM:85
85
85
81
80
83
85
85
85
85

83
80
85

14


2

(82, 85)


AM
145
145
135
125
B: 148
A: 125
105
105
115
135
125
125
115
110
102

122
102
145

14


14

(113,
132)

Feed Water
Pressure
78

80
78
78
82
78
78
78
78
80
78
80
82
80
79
78
82

14

2
(78,
80)

80

80
78
80
82
80
78
82
78
80
78
80
80
80
80
78
82

14

1
(79,
81)

(psi)
79

80
78
79
82
79
78
80
78
80
78
80
81
80
79
78
82

14

1
(79, 80)


PM
145
145
140
144
B110

Ave
145
145
138
135
AM: 137
A: 105 PM: 108
105
102
135
135
125
122
110
110
NA

125
102
145

13


17

(113,
137)

Inlet
Pressure
147

147
147
147
147
140
147
147
148
148
147
149
150
149
147
140
150

14

2
(146,149)

147

147
147
142
147
147
147
149
147
147
148
148
150
149
147
142
150

14

2
(146,
149)

105
104
125
135
125
124
113
110
102

123
102
145

14


15

(113,
133)


AM
65
70
70
75
B:90
A: 50
20
20
45
55
50
50
40
30
20

47
20
75

14


19

(34, 60)


PM
65
70
70
75
B: 35
A: 20
20
18
55
55
50
50
35
25
NA

47
18
75

13


21

(32,
62)


Ave
65
70
70
75
AM: 70
PM:28
20
19
50
55
50
50
38
28
20

46
19
75

14


20

(33,
59)

Back Pressure,
(psi)
147

147
147
145
147
144
147
148
148
148
148
149
150
149
147
144
150

14

2
(146, 148)

Concentrate Line psi)
65

65
65
65
65
65
68
68
68
65
65
70
70
68
67
65
70

14

2
(65, 68)

65

65
65
65
60
65
65
69
65
65
65
70
65
65
65
60
70

14

2
(64,
67)

65

65
65
65
63
65
67
69
67
65
65
70
68
67
66
63
70

14

2
(65,
67)

Tank Pressure,
Permeate Line (psi)

AM PM
4 4
2 2
2 2
4 4
B:2 B:0
A: 0 A: 0
0 0
0 0
2 0
0 0
0 0
0 0
0 0
0 0
0 NA

1 1
0 0
4 4

14 13


2 2

(0,2) (0,2)


Ave
4
2
2
4
AM: 1
PM:0
0
0
1
0
0
0
0
0
0

1
0
4

14


1

(0,2)

Tank Pressure,
Permeate Line
2 0

0.0 0
0.0 0
0.0 0
0.0 0
5.0 0
5.0 0
5.0 0
5.0 0
5.0 0
5.0 0
5.0 5
5.0 0
7.0 4
4 1
0 0
7 5

14 14

3 2
(2,5) (0,2)

(psi)
1

0
0
0
0
3
3
3
3
3
3
5
3
6
2
0
6

14

2
0,3)

  B= Before and A= After manual adjustments made to system.
Note: Only the 'after' values and averages on April 30,2004 are used in the statistical calculations.
NA = Not Applicable.
AM = First sample daily collection.
PM = Second sample daily collection.
                                                           52

-------
4.2.1.3 Water Recovery and Recycle Ratio
The  temporal profile  of  the  percent  water recovery over the verification testing  period  is
presented in Figure 4-3. The range of water recovery experienced during the verification testing
was  48% to 88% with an average of 53%.  The  manufacturer selected this  range of water
recovery after examination of the initial  operating data.  Higher recovery rates occurred from
April 26, 2004 to April 29, 2004, until the time the unit shut down for the first time. Per the
manufacturers recommendations, the  flow rates were  adjusted,  thus  effecting the percent
recoveries.   The data from April 30, 2004 through May 26, 2004 indicates a relatively constant
system recovery.



80-
«
60-


40-







20-



i
!
p
f
!{+--
»if
i
i ?N
j *
-------
  presented in Table 4-3 indicates that both the percent water recovery and the recycle ratio (both
  influences by  system flow rates) are influenced by the type  of pre-filter used with the M-15,000
  RO Treatment System.
Table 4-3: Water Recovery
Carbon Bloc Pre-
fllter
Date
4/26/04
4/27/04
4/28/04
4/29/04

4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04 (before)
Average
Minimum
Maximum
Number of
Samples
Standard Dev.
95% Confidence
Interval
Sediment
Pre-filter
5/1 3/04 (after)
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of
Samples
Standard Dev.
95% Confidence
Interval


AM
68
69
68
71
B1: 85
A1: 56
50
49
56
49
50
50
51
50
52
56
49
71
14

9

(51,62)


51
50
50
51
50
49
50
50
49
49
49
49
48
49
50
48
51
14

1
(49, 50)
and Recycle
Water
Recovery (%)
PM
69
69
68
88
B: 55
A: 51
50
50
49
49
50
50
51
51
NA
57
49
88
13

12

(49, 66)
Water
Recovery (%)
51
50
50
51
48
50
50
50
49
49
49
49
48
49
50
48
51
14

1
(49, 50)
Ratio


Ave
69
69
68
79
AM: 71
PM:53
50
50
53
49
50
50
51
51
52
57
49
79
14

10

(50, 63)


51
50
50
51
49
50
50
50
49
49
49
49
48
49
50
48
51
14

1
(49, 50)


AM
0.29
0.32
0.32
0.36
B:0.50
A:0.34
0.36
0.37
0.24
0.23
0.26
0.27
0.32
0.34
0.38
0.32
0.23
0.38
14

0.05

(0.28,0.35)


0.17
0.19
0.18
0.17
0.16
0.15
0.17
0.18
0.18
0.18
0.18
0.18
0.17
0.18
0.17
0.15
0.19
14

0.01
(0.17,0.18)

Recycle
Ratio
PM
0.31
0.32
0.31
0.43
B:0.38
A:0.35
0.36
0.37
0.23
0.23
0.26
0.27
0.33
0.35
NA
0.32
0.23
0.43
13

0.06

(0.28, 0.36)
Recycle
Ratio
0.17
0.19
0.18
0.17
0.15
0.17
0.17
0.17
0.18
0.18
0.18
0.18
0.17
0.18
0.17
0.15
0.19
14

0.01
(0.17,0.18)



Ave
0.30
0.32
0.32
0.39
AM:0.42
PM:0.37
0.36
0.37
0.23
0.23
0.26
0.27
0.32
0.34
0.38
0.32
0.23
0.39
14

0.05

(0.28,0.35)


0.17
0.19
0.18
0.17
0.15
0.16
0.17
0.17
0.18
0.18
0.18
0.18
0.17
0.18
0.17
0.15
0.19
14

0.01
(0.17,0.18)
 B= Before and A= After manual adjustments made to
Note: Only the 'after' values and averages on April 30,
NA = Not Applicable
AM = First sample daily collection
PM = Second sample daily collection
system.
2004 are used in the statistical calculations.
                                                   54

-------
4.2.1.4 Feed Water Temperature

Feed  water temperature measurements were  made twice daily  using a NIST  thermometer.
Temperatures were taken with each set of morning and evening analyses and ranged from 25.0°C
to 29.0°C with the morning samples and 27.0°C to 30.5°C with the evening samples (see Table
4-4).  The feed water temperature variance was taken into consideration when calculating the
temperature adjusted flux values presented in the following section, Section 4.2.1.5 Specific
Flux.
Table 4-4: Feed Water

Date
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/1 1/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of Samples
Standard Deviation
Temperature

AM
29.0
26.5
25.0
27.0
26.0
27.0
26.5
26.0
26.0
27.5
27.0
27.0
26.5
27.0
27.5
28.0
28.0
27.0
27.0
27.0
26.0
27.0
27.5
26.5
27.0
26.0
27.0
26.9
25.0
29.0
27
0.8
95% Confidence Interval (26.5, 27.2)

Temperature (°C)
PM
28.5
30.5
30.5
27.5
27.5
27.5
27.5
27.5
27.0
28.0
28.0
28.5
28.5
28.5
28.5
27.5
28.5
28.0
28.5
28.0
28.0
28.0
28.0
27.5
27.5
27.5
28.0
28.1
27.0
30.5
27
0.8
(27.7, 28.5)


Daily Average
28.8
28.5
27.8
27.3
26.8
27.3
27.0
26.8
26.5
27.8
27.5
27.8
27.5
27.8
28.0
27.8
28.3
27.5
27.8
27.5
27.0
27.5
27.8
27.0
27.3
26.8
27.5
27.5
26.5
28.8
27
0.5
(27.2, 27.7)
AM = First sample daily collection.
PM = Second sample daily collection.
                                           55

-------
4.2.1.5  Flux, Specific Flux, Net Driving Pressure, and Osmotic Pressure

Flux is  a method of expressing permeate flow through the membranes.  The flux was monitored
and  recorded daily throughout the  verification testing  period, and  the data  is graphically
presented in Figure 4-4 with the corresponding data presented in Table 4-5.  There are noticeable
declines in the flux, just prior to changing out the carbon bloc  pre-filter.  While the carbon bloc
pre-filter was in place, the  flux ranged from 24 to 41 gfd, with  an  average of 32 gfd, standard
deviation of 5 gfd,  and a 95% confidence interval of 28 to 36 gfd.  Once the sediment pre-filter
was put on-line,  the  flux stabilized with  an average 37 gfd,  a  range  of 35 to  28, a standard
deviation of 1 gfd, and a 95% confidence interval of 36 to 37  gfd.
      50
      40 :
      20 -
      10 -
                             Carbon Block
                             Pre-Filter Changed
                                                         Carbon Block Pre-Filter Replaced
                                                         with Sediment Pre-Filter
JN
Tp
                                                          O
                                                          ^5
                                                                      JN
                                                                      Ti
JN
ir>
                                      Verification Testing Date

                       Figure 4-4 Temporal plot of flux verses time.
                                            56

-------
 Table 4-5: Daily Flux Data

                            Flux (gfd)                                    Flux (gfd)
        Date         with Carbon Bloc Pre-filter         Date           with Sediment Pre-filter
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
Average
Minimum
Maximum
Number of Samples
Standard Deviation
95% Confidence
Interval
41
40
38
37
28
25
24
34
34
32
31
29
28
27
32
24
41
14
5
(28, 36)
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of Samples
Standard Deviation
95% Confidence
Interval
38
37
37
38
38
38
37
37
36
35
35
35
35
36
37
35
38
14
1
(36, 37)
Specific  flux  is used as an  indicator of general operational  performance.  Specific Flux is
calculated by flux at a constant temperature (in this case, normalized to 25°C) divided by the net
driving pressure. Normalizing the flux to a constant temperature helps to account for the effects
of viscosity of water at varying temperatures on the permeate flow through the membranes.  The
osmotic pressure data was calculated using daily TDS data and the pressures recorded during the
verification testing.

The specific flux normalized to 25°C (Equation 3.5) verses time over the verification testing
period is presented  in Figure 4-5 and Table 4-6.  In  Table 4-6, the specific flux is presented as
two data sets:  with  the carbon bloc pre-filter and the  sediment pre-filter. The specific flux while
using the carbon bloc pre-filter ranged from 0.32 gfd/psi to 0.44 gfd/psi, a 27% difference during
the 14-days of operation.  The  specific flux ranged from 0.32  gfd/psi to  0.38 gfd/psi, a 16%
difference, while the sediment pre-filter was utilized.  The modules were to be replaced if a 20%
decline in the specific flux was detected. However, since the study began at a specific flux of 38
gfd, the manufacturer was confident the testing should continue without replacing the modules.
Initial decreases in  the specific flux may be attributed to the aggressive operational  parameters.
Once the system was stabilized by replacing the carbon bloc pre-filter with a sediment pre-filter,
a steady specific flux was achieved.
                                            57

-------
    0.50
    0.45
 a.
 I
 U
 o
 u
 '0
 at
 a.
    0.40
    0.35 -
    0.30
                             Carbon Block
                             Pre-Filter Chansed
                                                      Carbon Block Pre-
                                                      Filter Replaced with
                                                      Sediment Pre-Filter

-------
The osmotic  pressure  gradient  is  the  difference  in  osmotic pressure  generated across the
membrane barrier as  a result of different concentrations of dissolved salts. IDS concentrations
were used as the constituent to calculate the daily osmotic pressure gradient from the verification
testing  (see  Equation  3-4).   This data  is graphically presented  in  Figure  4-6 with the
corresponding data shown in Table 4-7.  The range of osmotic pressure while the carbon bloc
pre-filter was  in use  was 1.7 to 4.5 psi.  When the  carbon bloc  pre-filter was replaced by the
sediment pre-filter, the range of osmotic pressure was 1.3 to 1.8 psi.
       5.0 -r
                                Carbon Block
                                Pre-Filter Changed
                                                         Carbon Block Pre-Filter
                                                         Replaced with Sediment
                                                         Pre-Filter
                                       o
                                       oo
o
•3-
o
l>
                                                                  o
                                                                  CN
                                                                                CN
                                                                                ft
                                     Verification Testing Date
                    Figure 4-6: Osmotic pressure gradient verses time.
                                            59

-------
Table 4-7: Os motic Pressure Gradient
     Date
        Osmotic
      Pressure (psi)
with Carbon Bloc Pre-filter
Date
       Osmotic
    Pressure (psi)
with Sediment Pre-filter
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
Average
Minimum
Maximum
Number of
Samples
Standard
Deviation
95% Confidence
Interval
2.5
2.6
2.6
4.5
1.9
2.0
1.9
1.8
1.9
1.9
1.8
1.9
1.8
1.7
2.2
1.7
4.5
14
0.7
(1.7,2.7)
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04

Average
Minimum
Maximum
Number of
Samples
Standard
Deviation
95% Confidence
Interval
1.8
1.8
1.7
1.6
1.6
1.6
1.7
1.5
1.4
1.4
1.5
1.3
1.5

1.6
1.3
1.8
13
0.2
(1.5,1.7)
Net driving pressure was calculated daily from the recorded feed water and concentrate streams
pressure, and is the average  of the feed water and concentrate pressure readings  minus the
permeate pressure and the osmotic pressure (see Equation 3-3).  The net driving pressure during
the verification testing period  is graphically presented in Figure 4-7 with the corresponding data
provided in Table  4-8.  As with other operating parameters, there was a  noticeable difference in
the net driving pressure while the carbon bloc pre-filter was in use, and what  appears to be
stabilization of the net driving pressure once the sediment pre-filter was  installed.   The average
net driving pressure with  the carbon bloc  filter was  83  psi,  compared  to  102 psi with the
sediment pre-filter.  Additionally, the standard deviation of the net driving pressure while the
carbon bloc pre-filter was in use was 14 psi, and was 2 psi while the  sediment pre-filter was in
use.
                                            60

-------
on
a.


1
Wl
Si
a.
G

"£
Z
                               Carbon Block

                               Pre-Filter Changed
     40
                                                      Carbon Block Pre-Filter

                                                      Replaced with Sediment Pre-
                                       o
                                       oo
o
^F
                                                                     o
                                                                     (N
                       CO
                       (N
                                                                                     (N
                                    Verification Testing Date


                 Figure 4-7:  Temporal profile of net driving pressure.
                                           61

-------
  Table 4-8:  Net Driving Pressure
       Date
 Net Driving Pressure (psi)
with Carbon Bloc Pre-filter
Date
Net Driving Pressure (psi)
 with Sediment Pre-filter
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
Average
Minimum
Maximum
Number of
Samples
Standard Deviation
95% Confidence
Interval
99
103
98
92
86
61
61
76
93
86
86
76
68
59
82
59
103
14
15
(71, 92)
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04

Average
Minimum
Maximum
Number of
Samples
Standard Deviation
95% Confidence
Interval
104
104
104
104
96
101
101
101
100
100
103
104
100

102
96
104
13
o
3
(100, 104)
4.2.2  Power Consumption

The  M-15,000  RO Treatment  System required 220 volts/11.5  amperage.   The  power
consumption in kilowatt-hours (KWH) to the system was  33  KWHs (on average) per day in
operation. The power consumption was monitored and recorded daily, as presented in Table 4-9.
The total power consumed for the 27 days of operation was 880 KWHs. The cost of electricity
was the primary consumable O&M cost for operating the system.
                                           62

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      Table 4-9:  Power Totalizer for M-15,000 RO Treatment System
Date
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Cumulative Power Totalizer Reading (KWH)
0
26
61
96
128
165
197
231
253
288
320
357
392
428
464
494
533
564
602
634
670
702
745
772
811
845
880
4.2.3  Consumables and Waste Generation

There were no "consumable" chemical items used for the verification testing; however, the pre-
filter to the system would be a consumable product and additional solid waste for disposal.  The
concentrate waste stream produced from the verification test was blended back with the permeate
water for an equivalent water quality to the feed water from the CVWD Well 7802.  This water
was then sent to a blow-off structure for disposal. The estimated concentrate production rate was
17,300 gallons per day, based on the targeted 50% recovery.   The concentrate stream water
quality characteristics are discussed in additional detail in Section 4.4 (Task 3).

4.3 Task 2: Cleaning Efficiency

The objective of this task was to evaluate the efficiency  of the membrane cleaning  procedures
recommended by  the manufacturer. The manufacturer proposes replacement of RO membranes
based on efficiencies of TDS reduction per module and quarterly maintenance procedures, which
involve replacement of pre-filters and RO module O-rings, in lieu of a cleaning procedure. While
not part of the quarterly maintenance procedures, two of the membranes  (membrane number 5
and 6) were also replaced during the  maintenance procedures to simulate a portion of annual
maintenance procedures.
                                           63

-------
The  total time to complete  the  O&M procedures was approximately 45  minutes.   Visual
inspection of the pre-filter and the membranes showed signs of red discoloration, assumed to be
iron, sediment, and/or other suspended solids filtered out or precipitated onto the membranes.
As previously discussed in Chapter 3,  prior to the system  being manually shut down for the
O&M procedures, the unit automatically shut down on two prior occasions.  It was believed that
the booster pump was being starved of water due to solids accumulation on the carbon bloc pre-
filter. Photograph 4 shows the three pre-filters used in the verification  study.  The first two are
carbon bloc pre-filters and the third filter is a pleated, sediment pre-filter.

        Photograph 4: Watts Premier M-15,000 RO Treatment System Pre-filters
Photograph 5 shows the condition of the RO membranes once removed from the system during
the O&M procedures performed after the verification testing.  There  appeared  to be "red"
discoloration and the presence of solids on the surface of the membranes, similar to those seen
on the pre-filters.
                                           64

-------
           Photograph 5: Membrane RO Number 6 - Post Verification Testing

4.3.1 Measure of Membrane Performance — Post Quarterly O&M Procedures

After completion of the O&M procedures, the M-15,000 RO Treatment System was placed back
on line to determine the effect of the O&M procedures on the model performance.  Table 4-10
lists  the  specific flux recoveries  and Table  4-11 list the maintenance  efficiency indictors
(performance indictors) prior to and after the O&M procedures.  In Table 4-11, the percent
recovery  of specific flux was calculated using Equation 3.14, expressed as the ratio between the
final specific flux (prior to the O&M procedures) and the initial  specific flux (post O&M
procedures).  There was little deviation between the specific flux prior to  and after the O&M
procedures, with a percent recovery of 97%.
                                           65

-------
Table 4-10: Pre-and Post-Maintenance Specific Flux Recoveries

Flux at Beginning of
Verification Study (4/26/04)
Flux Immediately Prior to
Quarterly O&M Procedures (5/26/04)
Flux After
Quarterly O&M Procedures (5/26/04)
Specific
Flux (gfd/psi)
0.38
0.34
0.33
% Recovery of
Specific
Flux (%)
97%
% Loss of Original
Specific
Flux (%)
13%
Table 4-11 Maintenance Efficiency Indicators

Flow Rate Prior to O&M Procedures, gpm
Flow Rate After O&M Procedures, gpm
Pressure Prior to O&M Procedures, psi
Pressure After to O&M Procedures, psi
Recovery Prior to O&M Procedures, psi
Recovery After to O&M Procedures, psi
Recycle Ratio Prior to O&M Procedures, psi
Recycle Ratio After to O&M Procedures, psi
Osmotic Pressure Prior to O&M Procedures, psi
Osmotic Pressure After to O&M Procedures, psi
Net Driving Pressure Prior to O&M Procedures, psi
Net Driving Pressure After O&M Procedures, psi
Temperature Prior to O&M Procedures, C
Temperature After to O&M Procedures, C
Feed Permeate Concentrate
Water
24.75 12.25 12.50
25.00 12.50 12.50
80 7 68
78 2 65
49
50
0.18
0.17
1.5
1.5
100
102
28.0
28.0
Recycle Inlet
5.34
5.28
149
147
--
--
-
-
--
A set of water samples for water quality analysis was collected just prior to and after the O&M
procedure.  This data is presented in Table 4-12.  From this table it appears that there is very
little difference between the before and after O&M procedure water quality.
                                           66

-------
Table 4-12:  Pre and Post O&M Feed Water, Permeate, and Concentrate Water Quality
Pre O&M May 24,
Parameter
Total Arsenic
Dissolved
Arsenic
As (III)
As(V)1
TOC
Calcium
Chloride
Hardness
Alkalinity
Free Chlorine
Total
Chlorine
pH
Turbidity
Conductivity
TDS
TSS
Manganese
Iron
Barium
Silica
Fluoride
Sulfate
Chromium
Vanadium
Units
Mg/L
Mg/L

Mg/L
Mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L
mg/L

-
NTU
umoh/cm
mg/L
mg/L
Mg/L
mg/L
Mg/L
mg/L
mg/L
mg/L
Mg/L
Mg/L
Feed Water
14
14

14
< 1.0
0.50
4.7
8.2
4
84
0.21
0.22

9.23
0.25
225
150
< 10
<2.0
0.023
7.3
14
0.78
19
13
51
Permeate
< 1.0
1.1

< 1.0
< 1.0
0.50
< 1.0
2.1
0
34
0.20
0.18

9.48
0.10
63.2
45
< 10
<2.0
< 0.010
<2.0
11
0.29
<2.0
< 1.0
5.3
2004
Concentrate
25
23

30
< 1.0
0.50
8.4
15
18
136
NA
NA

9.12
0.25
368
230
< 10
<2.0
0.023
12
17
1.2
38
23
88
Post
Feed Water
15
16

< 1.0
15
<0.50
4.7
8.7
4
82
0.35
0.35

9.17
0.20
231
140
< 10
<2.0
0.039
7.2
14
0.80
21
13
51
O&M May
Permeate
< 1.0
1.0

< 1.0
< 1.0
<0.50
< 1.0
1.7
0
26
0.32
0.33

9.41
0.10
52.6
34
< 10
<2.0
< 0.010
<203
8.2
0.24
<2.0
< 1.0
5.1
26, 2004
Concentrate
30
33

< 1.0
32
<0.50
8.7
15
10
132
NA
NA

9.10
0.40
387
230
< 10
<2.0
0.043
13
19
1.3
40
24
90
1 As (V) is a calculated value.
Conductivity
was measured twice per day.
3 Note: EPA Method 200.7
This value is
was used for this one analysis
the average of all the conductivity results.
withaMRLof20ng/L.


NA = Not applicable.

4.3.2 Review of Watts Premier Operation and Maintenance Manual

The Watts Premier O&M manual was previous discussed in Section 3.13.  These procedures
were followed on May 26, 2004, upon  completion of the verification study to simulate the
quarterly and a portion of the annual maintenance procedures. The O&M manual was very clear
and the maintenance procedure was completed in approximately 45 minutes.  Upon completion
of the O&M procedures, the system was started back up  and water quality data and operation
data was collected for comparison with the first startup of the equipment on April 26, 2004. As
with the maintenance procedures, the startup procedures were very clear and easy to follow as
well.

4.4 Task 3:  Feed Water And Treated Water Quality Monitoring

The objective of this task was to evaluate the quality of water produced by the membrane system
and the removal of inorganic chemical contaminants achieved by the membrane system at the
                                          67

-------
specified  operational conditions.   Monitoring of the water  quality parameters included the
following: arsenic  (total, As+3, and  dissolved),  pH, temperature, chloride, calcium, barium,
hardness,  conductivity, chlorine (total and free), TDS,  alkalinity, LSI, turbidity, TSS, silica,
fluoride, iron, manganese, sulfate, chromium, vanadium,  TOC and SDL  Water quality produced
was evaluated in relation to feed water quality and operational conditions. The verification study
indicated that arsenic can be removed by the M-15,000 RO Treatment System, but depending on
the source water characteristics, the appropriate pre-filter  selection is important  to prevent
clogging of the pre-filters.

In Figure  4-8, Temporal Plot of Total Arsenic,  all permeate values were non-detect (ND) with a
MRL of 1.0  |ig/L,  except on May 25, 2004, and May 26, 2004, which were 1.4 |ig/L and 1.2
|ig/L, respectively.  There was a spike in the concentrate total arsenic (84 |ig/L) just before the
first pre-filter was changed out on April 29, 2004, but returned to approximately 26 |ig/L for the
remainder of the study.   The cause of  the  concentrate  arsenic spike is  unknown, but was
indirectly   substantiated by  a  corresponding spike  in  the concentrate   TDS.    The  data
corresponding to Figure 4-8  is presented  in  Table  4-13. Mass balances  were calculated to
determine the  accumulation  of limiting  salts  on  the membrane surface.   Post-treatment
capabilities of  the  equipment were  also evaluated  for arsenic  (total, As+3, and  dissolved).
Additional information on the  mass balance for daily total arsenic (feed water, permeate, and
concentrate streams) is presented in  Section 4.4.2.1.
      90
o
1
•M
a

o
U
u
  o
  H
      60 -
      30 -
          n-n-o-rt
                                                                               Concentrate

                                                                               Feed Water

                                                                               Permeate
           o
          CN
               ON
               CN
CN
in
in
in
o
oo
in
o

-------
Table 4-13: Daily Feed Water, Concentrate, and Permeate Total Arsenic Data
        Date
   Feed Water
Total Arsenic (|Ig/L)
   Concentrate
Total Arsenic (|Ig/L)
    Permeate
Total Arsenic (|Ig/L)
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of Samples
Standard Deviation
95% Confidence Interval
13
13
13
13
13
14
12
12
15
14
13
14
14
13
13
13
13
14
15
14
13
15
14
13
14
15
16
14
12
16
27
1
(13, 14)
39
38
35
84
26
25
25
28
26
28
38
26
27
26
26
25
25
25
26
27
25
26
26
26
25
24
24
30
24
84
27
12
(24, 35)
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
1.0
1.4
1.2
< 1.0
< 1.0
1.4
27
0.1
(<1.0, 1.1)
In Figure 4-9, Temporal Plot of TDS, the feed water and permeate TDS show steady TDS levels
throughout the verification testing, with standard deviations of 6 and 12 mg/L, respectively. The
permeate TDS was below the detection limit of 10 mg/L at the beginning of the test, and slowly
increased to 34 mg/L on the last day of testing.   After the quarterly O&M  procedures were
performed, the permeate TDS was reduced by 26% to 34  mg/L (Table 4-12).  Throughout the
verification test, the TDS of the concentrate was less than 300 mg/L with the exception of the
first 4 days of the verification testing where the TDS fluctuated as high as 790 mg/L.  The data
corresponding to Figure 4-9 is presented in Table 4-14.
                                           69

-------
  1000 -r
"Si
   800 -
   600 -
o
f/3
Q

13
•M
o
H
400
200
                              n-n-n-O-o-OO
                                o
                                So
o
^F

iri
                                                  m
                                                                            Concentrate

                                                                            Feed Water

                                                                            Permeate
                                                    o
                                                    o
                           Verification Testing Date


                          Figure 4-9 Temporal plot of TDS.
                                          70

-------
Table 4-14: Daily Feed Water, Concentrate, and Permeate TDS

Date
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of Samples
Standard Deviation
95% Confidence Interval
Feed Water
TDS (mg/L)
150
140
150
140
1401
ISO1
140
130
150
140
130
130
140
130
1401
140
140
140
140
140
150
138
140
140
150
1301
140
140
130
150
27
7
(138, 143)
Concentrate
TDS (mg/L)
370
390
380
7901
2701
2601
2601
240
250
260
250
270
260
240
250
260
250
230
230
240
240
230
220
230
230
2101
230
279
210
790
27
112
(277, 282)
Permeate
TDS (mg/L)
<10
<10
<10
181
II1
<101
121
<10
11
<10
13
10
19
18
161
24
23
26
24
26
25
32
36
45
45
431
34
21
<10
45
27
12
(19, 23)
  Samples exceeded the laboratory RPD of 5%, as indicated in Table 3 -8.

Additional water quality monitoring included daily on-site analysis of pH and twice a day on-site
analysis  of  conductivity  for the feed water, permeate, and  concentrate streams.  Additional
weekly monitoring was conducted  for hardness, alkalinity, and turbidity.  Tables 4-15 and 4-16
present the data from the daily pH and conductivity measurements, and Table 4-17 presents the
data from the weekly hardness, alkalinity, and turbidity.  Free chlorine and total  chlorine were
monitored four times per week on the feed water (chlorinated  groundwater) and the permeate
from  the first  RO  membrane  (see  Table 4-18).   Data on  additional  inorganic constituents
(barium,  manganese, calcium, fluoride, chloride, chromium, sulfate, vanadium, iron, and  silica)
is presented in Section 4.4.1,  which  discusses  the  percent  removal of  these non-targeted
inorganic chemical constituents.
                                           71

-------
Samples were analyzed daily for pH and twice daily for conductivity from each of the three
sample streams (feed water, permeate, and concentrate).  Due to the log nature of pH, the median
value of the pH data has been present in lieu of the average.  There was a short range (minimum
to maximum  value) of pH values for each of the samples sets with the concentrate having the
greatest variability.  The feed water pH ranged from 8.97 to 9.27, concentrate from 8.67 to 9.19
and permeate from 9.23 to 9.66.

Table 4-15: Daily pH Analysis

        Date                Feed Water             Concentrate              Permeate
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Median
Minimum
Maximum
Number of Samples
9.26
8.98
9.06
9.14
9.09
9.13
8.97
9.09
9.21
9.20
9.08
9.23
9.24
9.10
9.20
9.23
9.20
9.24
9.27
9.24
9.23
9.23
9.21
9.24
9.23
9 22
9.20
9.21
8.97
9.27
27
9.04
8.95
9.01
8.67
9.03
9.10
8.90
9.00
9.12
9.11
9.12
9.14
9.10
9.06
9.11
9.12
9.11
9.14
9.16
9.13
9.19
9.16
9.15
9.16
9.12
9.12
9.15
9.12
8.67
9.19
27
9.43
9.23
9.28
9.30
9.48
9.50
9.49
9.30
9.61
9.56
9.60
9.65
9.66
9.38
9.50
9.57
9.53
9.47
9.49
9.56
9.57
9.52
9.51
9.51
9.48
9.45
9.41
9.50
9.23
9.66
27
The  permeate  conductivity slowly increased over the 27  operating days  of the verification
testing, beginning at 6.7 umoh/cm and ending with 76.7 umoh/cm (see Table 4-16).  This is an
indicator of a decline in membrane system performance or membrane integrity. As this decline
was  observed  even during constant operational conditions, it is suspected  that the  continued
exposure to low levels of chlorine for the duration of the ETV testing period was  leading to
membrane  integrity concerns.  The conductivity data indicated  a relatively steady state for the
feed water and concentrate streams, with one exception on  April 29, 2004 where the conductivity
spiked to 1302 umoh/cm in the concentrate.
                                           72

-------
Table 4-16:
Daily Conductivity Analysis
Feed Water (umoh/cm)
Date
4/26/04
4/27/04
4/28/04
4/29/04

4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of

Samples
Standard

Deviation
95%
Confidence
Interval
AM
190
209
232
236

239
245
233
238
245
245
237
242
240
243
241
240
241
244
224
234
230
224
228
226
225
230
230
233
190
245

27


12

(231,
235)

PM
192
202
233
248

227
243
228
244
214
239
224
246
244
239
244
241
231
237
222
227
222
227
224
228
227
228
228
230
192
248

27


13

(228,
232)

Ave
191
206
233
242

233
244
231
241
230
242
231
244
242
241
243
241
236
241
223
231
226
226
226
227
226
229
229
231
191
244
27



12

(229,
234)

Concentrate (umoh/cm)
AM
505
559
598
1302

431
449
434
423
428
424
426
439
437
414
411
420
416
408
401
398
387
381
377
371
368
393
362
458
362
1302

27


177

(456,
460)

PM
491
554
637
1282

412
440
424
426
425
430
433
439
437
417
414
421
409
398
398
391
374
378
375
374
370
391
361
456
361
1282

27


175

(453,
458)

Ave
498
557
618
1292

422
445
429
425
427
427
430
439
437
416
413
421
413
403
400
395
381
380
376
373
369
392
362
457
362
1292
27



176

(454,
459)

Permeate (umoh/cm)
AM
6.7
7.4
6.8
11.3

11.7
14.1
11.1
23.3
15.7
16.2
18.9
22.3
23.2
25.8
25.6
31.0
38.1
42.8
39.2
44.0
41.3
49.2
55.5
58.3
63.2
72.8
76.5
32
6.7
76.5

27


21

(29, 34)

PM
7.5
5.4
8.2
12.2
B1 • 112
A1: 7.1
11.2
12.2
15.2
13.2
15.9
18.3
22.8
23.5
24.7
25.8
32.3
35.1
39.8
39.1
40.6
43.3
50.0
53.3
60.1
64.1
74.1
76.7
31
5.4
76.7
27



21

(29, 33)

Ave
7.1
6.4
7.5
11.8
AM: 11.7
PM: 9.2
12.7
11.7
19.3
14.5
16.1
18.6
22.6
23.4
25.3
25.7
31.7
36.6
41.3
39.2
42.3
42.3
49.6
54.4
59.2
63.7
73.5
76.6
31
6.4
76.6

27


21

(29, 33)

 B= Before and A= After manual adjustments made to system.
Note: Only the 'after' permeate value and average on April 30, 2004 was used in the statistical calculations.
AM = First sample daily collection.
PM = Second sample daily collection.

Table 4-17 presents the weekly on-site hardness, alkalinity, and turbidity analyses.  Feed water
during the test was soft and the system  completely  removed any hardness present. Permeate
hardness in all of the analyses was 0 mg/L, while the concentrate hardness was approximately
double that of the feed water.  Similarly, the alkalinity was reduced by approximately 72% in the
permeate and almost doubled  in  the concentrate compared to the feed water alkalinity.   The
turbidity analysis ranged from 0.25 to 0.55 NTU in the feed water and 0.10 to  0.20  NTU in the
permeate with an average percent turbidity removal of 63%.
                                             73

-------
Table 4-17: On-site Weekly Water Quality Monitoring


Date
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04
Average
Minimum
Maximum
Number of
Samples


Date
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04
Average
Minimum
Maximum
Number of
Samples

Feed
Water
20
22
20
22
4
18
4
22
5


Feed
Water
0.43
0.53
0.51
0.23
0.24
0.40
0.25
0.55
5

Hardness (mg/L)

Concentrate
40
44
44
34
18
36
18
44
5

Turbidity (NTU)

Concentrate
0.50
0.52
0.54
0.28
0.25
0.40
0.25
0.55
5



Permeate
0
0
0
0
0
0
0
0
5



Permeate
0.17
0.13
0.18
0.19
0.10
0.15
0.10
0.20
5


Feed
Water
74
88
82
88
84
83
74
88
5

Alkalinity (mg/L)

Concentrate
206
140
144
130
136
151
130
206
5



Permeate
12
18
22
28
34
23
12
34
5


  Table 4-18 presents the results of the free and total chlorine on-site analysis from the feed water
  and the permeate (note:  permeate samples were collected immediately after the first membrane
  which was identified as the first available sample location downstream of the pre-filter).

  Since the carbon bloc pre-filter was replaced with a sediment pre-filter, the data presented in
  Table 4-18 as been broken into two sets of data, one with the carbon bloc pre-filter and one set
  with the sediment pre-filter.  The results of the first set of data indicate that the  carbon bloc pre-
  filter removed 51% of the free chlorine and 53% of the total chlorine.  This may have been due
  in part to the feed water flow rates not allowing sufficient contact time in the  pre-filter for the
  carbon bloc to be 100% effective.

  Once the sediment pre-filter was placed in service (in lieu of the carbon bloc  pre-filter), there
  was still a small reduction in chlorine removal, 19% of the  free chlorine and 21% of the total
  chlorine.  It  is evident that chlorine is  breaking through the pre-filter (with either type of pre-
  filter). This may be a contributing factor to the decline in membrane performance during the
  verification test and may have a significant long-term impact, which cannot be determined by the
  data available from this verification test.
                                             74

-------
Table 4-18: On-Site Free and Total Chlorine Monitoring
Date
4/26/2004
4/27/2004
4/28/2004
4/30/2004
5/7/2004
5/8/2004
5/9/2004
5/10/2004
5/11/2004
5/12/2004
Average
Minimum
Maximum
Number of Samples
Standard Deviation
95% Confidence
Interval
5/14/2004
5/17/2004
5/18/2004
5/19/2004
5/21/2004
5/24/2004
5/25/2004
5/26/2004
Average
Minimum
Maximum
Number of Samples
Standard Deviation
95% Confidence
Interval
Free Chlorine
Feed Water
0.51
0.92
0.98
0.45
0.45
0.71
0.30
0.54
0.56
0.46
0.59
0.30
0.98
10
0.22
(0.40, 0.77)
0.68
0.42
0.38
0.02
0.43
0.21
0.03
0.34
0.31
0.02
0.68
8
0.22
(0.09, 0.54)
(mg/L)
Permeate1
0.27
0.56
0.29
0.26
0.36
0.21
0.12
0.21
0.30
0.35
0.29
0.12
0.56
10
0.12
(0.19,0.39)
0.52
0.40
0.30
0.00
0.19
0.20
0.02
0.33
0.25
0.00
0.52
8
0.18
(0.06, 0.43)
Total Chlorine
Feed Water
0.94
0.92
0.98
0.52
0.43
0.78
0.40
0.55
0.56
0.48
0.66
0.40
0.98
10
0.23
(0.46, 0.85)
0.73
0.42
0.39
0.04
0.44
0.22
0.04
0.34
0.33
0.04
0.73
8
0.23
(0.10,0.56)
(mg/L)
Permeate1
0.27
0.56
0.29
0.26
0.20
0.45
0.18
0.21
0.30
0.36
0.31
0.18
0.56
10
0.12
(0.21, 0.41)
0.48
0.39
0.31
0.02
0.37
0.18
0.02
0.34
0.26
0.02
0.48
8
0.17
(0.09, 0.44)
  Permeate chlorine samples were collected just after the first membrane.

4.4.1  Percent Removal of Inorganic Chemical Constituents

Speciated arsenic data is presented in Table 4-19. Three forms of arsenic were evaluated on a
weekly basis:  total, dissolved,  and arsenite.  The majority of the arsenic appears to be  in the
dissolved form. There is a noticeable discrepancy on the May 24, 2004 sampling date with
respect to the concentrate samples, where the arsenite is greater than both the dissolved and the
total arsenic.   This may  be  due to a number of issues, including  sampling error, laboratory
interference, or other unknown causes of interference.

The arsenate data are calculated values by subtracting the arsenite value from the dissolved
arsenic value. From the data presented, the majority of the arsenic was in the arsenate form, with
the exception of the May 24, 2004 sample where the feed water appears to be primarily in the
arsenite form.
                                            75

-------
Table 4-19: Weekly Speciated Arsenic Analysis

Date1
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04
Average
Minimum
Maximum
Number of
Samples

Total

Arsenic (|Ig/L)
Feed
Water Cone. Perm.
13
12
13
15
14
13
12
15
5
39
28
38
28
25
32
25
39
5
< 1.0
< 1.0
< 1.0
< 1.0
1.0
< 1.0
< 1.0
5

Dissolved
Arsenic (|Ig/L)
Feed
Water Cone. Perm.
16
14
13
14
14
14
13
16
5
39 < 1.0
26 < 1.0
31 <1.0
26 < 1.0
23 1.1
29 < 1.0
23 < 1.0
39 1.1
5 5
Arsenite (|Ig/L)
Feed
Water
< 1.0
< 1.0
< 1.0
1.3
14
3.7
< 1.0
14
5
Cone. Perm.
1.7 1
< 1.0 1
1.4 <
1.4 <
30 <
7.1 1
< 1.0 <
30 1
5
.3
.5
1.0
1.0
1.0
2
.5
5
Arsenate (|Ig/L) 1
Feed
Water
15
13
12
12.7
< 1.0
11
< 1.0
15
5
Cone.
37.3
25
29.6
24.6
< 1.0
24
< 1.0
37.3
5
Perm.
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
< 1.0
5
    1  Arsenate results are calculated values.

    The  results of the weekly sampling  of inorganic constituents  and the percent removal  of the
    inorganic constituents are presented Table 4-20 followed by temporal plots for each significant
    inorganic  constituent (Figures 4-10 to 4-14).  Manganese was not plotted as the feed  water,
    permeate,  and concentrate analyses were all below the MRL of 2.0 ng/L.  The testing unit was
    effective at reducing the following inorganic constituents to non-detectable levels: barium,
    calcium, iron, chromium, and sulfate. Significant levels of fluoride, chloride, and vanadium were
    also  removed. Silica had a declining rate of removal, beginning with 91% removal and ending
    with 21%  removal.  The level of manganese removal could not be determined, as both the  feed
    water and permeate concentrations were below the detection limit.
                                               76

-------
Table 4-20: Weekly Analytical Parameters and

Barium
 69%
> 74%
> 75%
> 68%
> 73%
> 72%
> 68%
> 75%
5

> 80%
> 79%
> 79%
> 77%
> 79%
> 79%
> 77%
> 80%
5
Chloride (mg/L)
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04
Average
Minimum
Maximum
Number of Samples
8.9
8.4
8.7
8.2
8.2
8.5
8.2
8.9
5
25
16
17
15
15
18
15
25
5
< 1.0
< 1.0
< 1.0
1.1
2.1
1
< 1.0
2.1
5
> 89%
> 88%
> 89%
87%
74%
85%
74%
> 89%
5
Sulfate (mg/L)
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04
Average
Minimum
Maximum
Number of Samples
21
20
21
20
19
20
19
21
5
60
39
41
39
38
43
38
60
5
<2.0
<2.0
<2.0
<2.0
<2.0
<2.0
<2.0
<2.0
5
> 90%
> 90%
> 90%
> 90%
> 89%
> 90%
> 89%
> 90%
5
Iron (mg/L)
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04
Average
Minimum
Maximum
Number of Samples
0.012
0.033
0.019
0.010
0.023
0.019
0.010
0.033
5
< 0.010
0.028
0.018
< 0.010
0.023
0.018
< 0.010
0.028
5
< 0.010
< 0.010
< 0.010
< 0.010
< 0.010
< 0.010
< 0.010
< 0.010
5
> 17%
> 70%
> 47%
> 0 %
> 57%
38%
> 0 %
> 70%
5
Feed
Water
<2.0
<2.0
<2.0
<2.0
<2.0
<2.0
<2.0
<2.0
5

0.82
0.79
0.80
0.80
0.78
0.80
0.78
0.82
5

13
13
13
13
13
13
13
13
5

45
51
51
49
51
49
45
51
5

14
15
17
15
14
15
14
17
5

Manganese (jig/L)
Concen-
trate Permeate
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
5 5
Fluoride (mg/L)
2.2 < 0.050
1.4 < 0.050
1.4 0.06
1.4 0.16
1.2 0.29
1.5 0.12
1.2 < 0.050
2.2 0.29
5 5
Chromium (jig/L)
36 <1.0
23 <1.0
23 <1.0
24 <1.0
23 <1.0
26 <1.0
23 <1.0
36 <1.0
5 5
Vanadium (Jig/L)
130 <3.0
80 < 3.0
84 < 3.0
90 < 3.0
88 5.3
94 < 3.0
80 < 3.0
130 5.3
5 5
Silica (mg/L)
39 1.2
24 3.4
24 4.2
20 8.4
17 11
25 5.6
17 1.2
39 11
5 5


Percent
Removal
NA
NA
NA
NA
NA
NA
NA
NA
NA

> 94%
> 94%
93%
80%
63%
85%
63%
> 94%
5

> 92%
> 92%
> 92%
> 92%
> 92%
> 92%
> 92%
> 92%
5

> 93%
> 94%
> 94%
> 94%
90%
> 93%
90%
> 94%
5

91%
77%
75%
44%
21%
62%
21%
91%
5
  The ">" symbol in the percent removal column indicates that the analysis was below the MRL.
2 NA = Not Applicable; Feed water and permeate were both below the detection limit;
                                                      77

-------
                                                                      -•—Feed Water

                                                                      -O— Permeate

                                                                          Concentrate
                         Verification Testing Date


                       Figure 4-10:  Temporal plot of silica.
   2.5
                                               MRL = 0.050 mg/L
o
   1.5 -
     1 -
   0.5 -
        Q-
                                                                       • Feed Water

                                                                      -O—Permeate

                                                                      -D— Concentrate
o
o
(N


(N

^t
                O
                O
                CN
O
O
(N

^

1/1
o
o
o
o
(N
o
o
(N
o
o
(N

O
(N
O
O
CN


CN

1/1
                           Verification Testing Date


                     Figure 4-11:  Temporal plot of fluoride.
                                         78

-------
I  o.ois  H
                                                                           Feed Water


                                                                           Permeate


                                                                           Concentrate
                          Verification Testing Date



                        Figure 4-12: Temporal plot of iron.
    30'
    25-1
                                                MRL = 1.0 mg/L
•a   I
•c
_o

U   10-.
     5-
                                                                      -•— Feed Water

                                                                      -O— Permeate

                                                                      -O- Concentrate
o
o
CN


tS

•^
                o
                o
                ts
O
O

-------
70




60-




50-




40-




30-




20-




10-




 0
         O-
o
o
JN


JN

^
                                                 MRL = 2.0 mg/L
            -O-
                  o
                  o
                  JN
O
O
(N

Jt

LD
o
o
CN

^
>J->
o
o
(N
o
o
JN
                                                      o
                                                      o
                                                      JN

                                                      O
                                                      (N
                -o—o
                                                                            —•—Feed Water


                                                                            —O—Permeate


                                                                            —Cl— Concentrate
O
O
JN



JN

i^l
                                Verification Testing Date
                           Figure 4-14: Temporal plot of sulfate.
4.4.2 Percent Removal of Organic Constituents



Samples for TOC were also collected on a weekly basis. The results of the sampling indicated

that for this water source, the feed, concentrate and permeate had non-detectable levels of TOC,

see Table 4-21.
Table 4-21: Percent Removal of Organic

Date
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04
Average
Minimum
Maximum
Number of Samples
Total
Feed Water
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
5
Constituents
Organic Carbon (mg/L)
Concentrate
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
5


Permeate
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
<0.50
5

Percent
Removal
NA1
NA
NA
NA
NA
NA
NA
NA
5
 NA = Not applicable as all samples contained non-detectable levels of TOC.
                                             80

-------
4.4.2.1 Mass Balance for Total Arsenic

A mass balance through the M-15,000 RO Treatment System for total arsenic was conducted.
The equation used for the mass balance was previously presented in Equation 3-10: QfCf = QPCP
+ QcwCcw. In this equation, QfCf represents the feed water flow rate multiplied by the feed water
total arsenic concentration, QPCP  represents the permeate flow multiplied by the permeate total
arsenic concentration, and lastly,  QcwCCw represents the concentrate flow rate multiplied by the
concentrate total arsenic concentration.  The total arsenic mass balance was calculated for each
day the M-15,000 RO Treatment  System was in operation during  the verification test. The data
is graphically presented in Figure 4-15  and the  corresponding data is provided in Table 4-22.
Throughout most of the verification test, the total arsenic mass balance was very close, with the
exception of April 29, 2004, and  May  10, 2004,  where  the  arsenic  concentration in the
concentrate stream  was significantly higher (greater than the 95%  confidence interval), at 84
(ig/L and 38 |j,g/L respectively.
        500
    5
    a.
    OK
    o
400 -
        300 -
        200 -
        100 -
   •
   H
                                                               QpCp+QcwCcw
                                                               QfCf
                                                                       o
                                                                       
-------
Table 4-22: Daily Total Arsenic Mass Balance

Date
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04
Average
Minimum
Maximum
Number of Samples
Standard Deviation
95% Confidence Interval
QfCf
(gpm-Hg/L)
267
254
247
234
234
238
201
276
349
308
280
277
266
332
328
325
332
364
398
350
325
375
343
319
343
375
396
309
201
398
27
54
(284, 333)
Qc + o c
p p ^ccw^cw
(gpm-Hg/L)
268
242
223
450
231
221
221
334
317
319
419
264
266
338
338
325
326
338
364
350
325
344
337
337
325
329
315
313
221
450
27
56
(288, 339)
4.4.2.2 Limiting Salt Concentrations

The  limiting salt  concentrations were calculated  using  Equation 3.11  once per week  and
compared to standard  Solubility Product values to determine if the  salt concentrations were
posing a limitation to operational system recovery,  presented in Table  4-23. The salts that were
evaluated were calcium  carbonate  (CaCOs),  barium  sulfate  (BaSO/t),  and calcium  sulfate
(CaSO4).

Barium Sulfate
As shown in Table 4-23, the solubility product of barium sulfate in the  feed water, permeate, and
concentrate was less than the theoretical solubility product, indicating that barium sulfate would
remain in a soluble state.
                                           82

-------
Calcium Carbonate
Each  of the calcium carbonate samples  (feed water, permeate,  and concentrate) samples had
solubility  products  greater than the theoretical solubility product.  Thus,  it is expected that
calcium carbonate would precipitate out of each of the three streams.  This is a concern for the
long-term operation of the membranes, as the precipitation of salts on the membranes could lead
to fouling resulting in a decline in system performance.

Calcium Sulfate
Each  of the calcium sulfate  samples (feed water, permeate, and  concentrate)  samples had
solubility  products  less than the theoretical solubility  product. Thus,  calcium sulfate would
remain in  solution for of each of the three streams.

Table 4-23: Solubility Products of Limiting Salt Concentrations
Theoretical
Solubility
Product



1.1E-10






6.1E-5



Feed
Water


5.8E-12
6.6E-12
7.6E-12
5.5E-12
6.0E-12
6.7E-12

1.6E-08
1.4E-08
1.5E-08
1.3E-08
1.3E-08
1.5E-08
Permeate Concentrate Theoretical


Barium Sulfate
1.7E-13
1.7E-13
1.8E-13
1.8E-13
1.7E-13
1.8E-13
Calcium Sulfate
3.0E-10
3.0E-10
3.1E-10
3.0E-10
3.0E-10
3.0E-10
Solubility
Product
Feed
Water

Permeate


Concentrate


Calcium Carbonate
4.7E-11
2.4E-11
2.4E-11 8.7E-9
2. IE- 11
2.0E-11
2.3E-11

1.2E-07
5.2E-08
5.7E-08
4.7E-08
4.7E-08
5.2E-08
5.4E-08
6.0E-08
5.8E-08
5.6E-08
5.6E-08
5.6E-08







1.7E-09
2.6E-09
3.2E-09
4.1E-09
4.8E-09
1.9E-08







3.8E-07
1.8E-07
1.9E-07
1.5E-07
1.6E-07
9.7E-08







4.4.3   Removal of TSS

TSS was monitored on a weekly basis, as presented in Table 4-24.   The source water for the
verification testing was chlorinated groundwater, and  not anticipated to have high-suspended
solids.  The feed water, concentrate, and  permeate samples collected during the verification
testing all had non-detectable levels of TSS, with a detection limit of 10 mg/L.
                                           83

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Table 4-24: Removal of Total Suspended Solids

      Date                               Total Suspended Solids (mg/L)
                     Feed Water         Concentrate           Permeate        Percent Removal
4/26/04 < 10
5/7/04 < 10
5/10/04 < 10
5/18/04 < 10
5/24/04 < 10
Average < 10
Minimum < 10
Maximum < 10
Number of Samples 5
< 10 < 10 NA1
< 10 < 10 NA
< 10 < 10 NA
< 10 < 10 NA
< 10 < 10 NA
< 10 < 10 NA
< 10 < 10 NA
< 10 < 10 NA
555
 NA = Not applicable as all samples contained non-detectable levels of TOC.

 4.4.4 SDI

 SDI is the measurement of the quantity  of suspended solids  in  a  water supply that  could
 potentially foul RO membranes.  A 5-gallon sample of the feed water was  collected on the last
 day of the verification testing.  The SDI measurements were run in duplicate from this sample
 and found to be 3.12 and 3.10.  The  SDI results reveal relatively solids free water, which is
 consistent with the TSS analyses (all TSS samples were below the MDL of 10 mg/L).  The filter
 volume for each test was 250 milliliter (mL) and Pall Acrodisk 25-mm syringe filters  (0.45 |j,m
 diameter) were used for study. A blank SDI was run using de-ionized (DI) water, with a result of
 2.57. The results of the SDI test and the method are available in Appendix E.

 4.4.5 LSI

 The LSI was calculated at the beginning of the verification testing (April 26,  2004) with the
 following equation: LSI = pH - pHs, where pH is the measured pH of the water and pH is the pH
 at saturation  (calcium carbonate).

           pHs = (9.3 + A + B) - (C + D).

 where:  A = (Logic [TDS] - 1) / 10
         B = -13.12 x Logio (°C + 273) + 34.55
         C = Logic [Ca2+ as CaCCb] - 0.4
         D = Logic [alkalinity as CaCOs]

 The LSI is an indictor of how corrosive or scaling a water may be primarily based on the TDS,
 calcium, water temperature,  and alkalinity.   On April 26, 2004 the LSI of the feed water,
 permeate, and concentrate was calculated and the data is  presented  in Table 4-25.  From the
 calculation,  the  feed water is  at equilibrium,  the permeate  is  slightly  corrosive and the
 concentrate is in a slightly scaling state.
                                            84

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Table 4-25:
A
B
C
D
pH
pHs
LSI
LSI Calculations (April 26, 2004)
Feed water
0.1176
2.0218
0.3076
1.8692
9.26
9.26
0.00
Permeate
0.0000
2.0218
-0.4000
1.0792
9.43
10.64
-1.21
Concentrate
0.1568
2.0218
0.7139
2.3139
9.04
8.45
0.59
4.5 Task 4: Data Handling Protocol

The objective of this task was to establish an effective field protocol for data management at the
field operations  site and for  data transmission between the FTO  and NSF during verification
testing.  Prior to the beginning of field testing, the database or spreadsheet design was developed
by the FTO and reviewed and approved by NSF.  This ensured that the required  data was
collected during the testing, and that results could be effectively transmitted to NSF for review.
The FTO followed all data handling procedures that were presented in  Chapter 3. Additional
details on data handling were  previously discussed in Section 3.11.

4.6 Task 5: Quality Assurance/Quality Control Results

An important aspect of verification testing is the Quality Assurance  Project  Plan (QAPP)
developed for QA/QC, as described in  Section 3.12.  The objective of this task  was to assure
accurate measurement of operational and water quality parameters during membrane equipment
verification  testing.   The  primary  areas  of  evaluation  were  precision,  accuracy,  statistical
uncertainty,  and completeness.  Statistical uncertainty was discussed in Section 3.12.4.2  and
presented in  tables containing eight or more  data sets,  presented in Chapter  4 as the 95%
confidence interval.

Each day the tubing, fittings,  and general condition of the M-15,000 RO Treatment System were
inspected to verify that there were  no  leaks or needed repairs.  There were no leaks to report
from tubing,  however daily inspection  of the membrane  housings revealed intermittent leaks,
which alternated between each of the six housings, as noted in the field logbook.

4.6.1  Precision

Precision  refers  to the degree of mutual agreement among individual measurements,  and was
discussed in  Section 3.12.5  and 3.12.6.   The percent acceptable precision among  duplicate
samples was previously presented in Table 3-7 and the calculated precision for each analytical
parameter is presented in the  following tables.   The precision calculations of the weekly off-site
duplicate  analyses are presented in Table 4-26 and the weekly on-site  duplicate analyses  are
presented in Table 4-27.  Note that only the feed water  and permeate samples were  taken in
duplicate for  the on-site  duplicate analysis  of chlorine  (free and total) and that  only  the feed
water was taken  in duplicate for temperature (twice weekly).  All analyses presented in Tables 4-
                                            85

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26 and 4-27 were within the acceptable precision percentage, with the exception of one free
chlorine sample collected on May 19,  2004 (47% precision), which  had very low levels  of
chlorine (0.02 and 0.01 mg/L in the sample and duplicate, respectively), and eight of the twenty-
seven pH duplicate samples.  Analytical precision was calculated for pH based  on duplicate
samples that were collected  seven times per week. The pH values were converted to hydrogen
ion concentrations and the percent precision was calculated from the hydrogen ion concentration.
For the data presented in Table 4-27, the hydrogen ion concentration was calculated as:

              pH = -  log [Hydrogen ion concentration]

TDS duplicates were collected four times per week and the data is presented in Table 4-28.  All
TDS duplicate analyses were within the acceptable precision percentage of 30%. Conductivity
duplicates were collected  eight times  per week and the data is presented  in Table 4-29.  Total
arsenic  duplicates were collected daily, with  the results of  the  duplicate precision analysis
presented in Table 4-30.  The percent precision values for all the conductivity and total arsenic
data  sets were within  the acceptable limits.  An SDI measurement was  required once during the
verification testing period.   The water for this  analysis was collected in duplicate on May 26,
2004, with a percent precision of 0.6%.

Precision checks performed  by the MWH Laboratory were within the acceptable limits outlined
in Table 3-8, except for some TDS samples, as indicated in Table 4-14.
                                            86

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Table 4-26


Date
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04


4/26/04
5/7/04
5/10/04
5/18/04
5/24/04


4/26/04
5/7/04
5/10/04
5/18/04
5/24/04


4/26/04
5/7/04
5/10/04
5/18/04
5/24/04


4/26/04
5/7/04
5/10/04
5/18/04
5/24/04

: Weekly Off-Site Analytical
Barium (|Ig/L)
Sample
Location Sample Duplicate
permeate < 2.0 < 2.0
concentrate 14 14
feed water 8.1 7.4
permeate < 2.0 < 2.0
concentrate 12 12
Acceptable Precision
Calcium (mg/L)
permeate < 1.0 < 1.0
concentrate 9.1 9.1
feed water 4.8 4.8
permeate < 1.0 < 1.0
concentrate 8.4 8.5
Acceptable Precision
Chloride (mg/L)
permeate < 1.0 < 1.0
concentrate 16 17
feed water 8.7 8.7
permeate 1.1 1.1
concentrate 15 15
Acceptable Precision
Sulfate (mg/L)
permeate < 2.0 < 2.0
concentrate 39 39
feed water 21 21
permeate < 2.0 < 2.0
concentrate 38 38
Acceptable Precision
Iron (mg/L)
permeate < 0.010 < 0.010
concentrate 0.028 0.042
feed water 0.019 0.019
permeate < 0.010 < 0.010
concentrate 0.023 0.022
Acceptable Precision
Precision

Percent
Precision
0.0%
0.0%
6.0%
0.0%
0.0%
30%

0.0%
0.0%
0.0%
0.0%
1.0%
30%

0.0%
4.0%
0.0%
0.0%
0.0%
20%

0.0%
0.0%
0.0%
0.0%
0.0%
20%

0.0%
28%
0.0%
0.0%
3.0%
30%
TOC (mg/)
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04

permeate < 0.50 < 0.50
concentrate < 0.50 < 0.50
feed water < 0.50 < 0.50
permeate < 0.50 < 0.50
concentrate < 0.50 < 0.50
Acceptable Precision
0.0%
0.0%
0.0%
0.0%
0.0%
30%
Sample
Location
permeate
concentrate
feed water
permeate
concentrate


permeate
concentrate
feed water
permeate
concentrate


permeate
concentrate
feed water
permeate
concentrate


permeate
concentrate
feed water
permeate
concentrate


permeate
concentrate
feed water
permeate
concentrate


Manganese (|Ig/L)

Sample Duplicate
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
<2.0 <2.0
Acceptable Precision
Fluoride (mg/L)
< 0.050 < 0.050
1.4 1.4
0.80 0.8
0.16 0.16
1.2 1.2
Acceptable Precision
Chromium (|Ig/L)
< 1.0 <1.0
23 22
13 13
< 1.0 <1.0
23 23
Acceptable Precision
Vanadium (|Ig/L)
<3.0 <3.0
80 80
51 45
<3.0 <3.0
88 87
Acceptable Precision
Silica (mg/L)
1.2 1.2
24 24
17 15
8.4 8.4
17 17
Acceptable Precision


Percent
Precision
0.0%
0.0%
0.0%
0.0%
0.0%
30%

0.0%
0.0%
0.0%
0.0%
0.0%
20%

0.0%
3.0%
0.0%
0.0%
0.0%
30%

0.0%
0.0%
9.0%
0.0%
1.0%
30%

0.0%
0.0%
9.0%
0.0%
0.0%
30%
TSS (mg/L)
permeate
concentrate
feed water
permeate
concentrate

< 10 < 10
< 10 < 10
< 10 < 10
< 10 < 10
< 10 < 10
Acceptable Precision
0.0%
0.0%
0.0%
0.0%
0.0%
30%
87

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Table 4-27


Date
4/26/04
5/7/04
5/10/04
5/18/04
5/24/04


4/26/2004
4/28/2004
4/30/2004
5/2/2004
5/7/2004
5/9/2004
5/10/2004
5/12/2004
5/14/2004
5/18/2004
5/19/2004
5/21/2004
5/24/2004
5/26/2004


4/26/04
4/30/04
5/7/04
5/10/04
5/14/04
5/18/04
5/21/04
5/24/04

: On-Site Analytical Precision
Hardness (mg/L)
Sample


Percent
Location Sample Duplicate Precision
permeate 0 0
concentrate 44 42
feed water 20 22
permeate 0 0
concentrate 18 20
Acceptable Precision
Free Chlorine (mg/L)
permeate 0.27 0.28
feed water 0.98 0.97
feed water 0.45 0.46
permeate 0.13 0.14
feed water 0.45 0.45
permeate 0.12 0.16
feed water 0.54 0.50
permeate 0.35 0.29
permeate 0.52 0.51
permeate 0.30 0.39
feed water 0.02 0.01
feed water 0.43 0.44
feed water 0.21 0.20
permeate 0.33 0.33
Acceptable Precision
Temperature ("C)1
feed water 29.0 29.0
feed water 27.5 27.5
feed water 27.5 27.5
feed water 27.0 27.0
feed water 28.5 28.5
feed water 27.0 27.0
feed water 28.0 28.0
feed water 27.0 27.0
Acceptable Precision
0.0%
3.0%
7.0%
0.0%
7.0%
30%

2.6%
0.7%
1.6%
5.2%
0.0%
20%
5.4%
13%
1.4%
18%
47%
1.6%
3.4%
0.0%
30%

0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
10%
Sample
Location
permeate
concentrate
feed water
permeate
concentrate

Alkalinity

Sample
12
140
82
28
136

(mg/L)

Duplicate
12
138
84
30
134
Acceptable Precision


Percent
Precision
0.0%
1.0%
2.0%
5.0%
1.0%
30%
Total Chlorine (mg/L)
permeate
feed water
feed water
permeate
feed water
permeate
feed water
permeate
permeate
permeate
feed water
feed water
feed water
permeate


permeate

concentrate
feed water

permeate

concentrate
0.27
0.98
0.52
0.14
0.43
0.18
0.55
0.36
0.48
0.31
0.04
0.44
0.22
0.34
Acceptable
Turbidity
0.17

0.52
0.51

0.19

0.25
0.28
0.98
0.50
0.15
0.46
0.20
0.52
0.30
0.51
0.40
0.04
0.44
0.19
0.33
Precision
(NTTJ)
0.16

0.54
0.52

0.20

0.24
Acceptable Precision
2.6%
0.0%
2.8%
4.9%
4.8%
7.4%
4.0%
13%
4.3%
18%
0.0%
0.0%
10%
2.1%
30%

4.0%

3.0%
1.0%

4.0%

3.0%
30%
88

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Table 4-27: On-Site Analytical
pH
Sample
Date Location Sample
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04

permeate
concentrate
feed water
permeate
concentrate
feed water
permeate
concentrate
feed water
permeate
feed water
permeate
concentrate
feed water
permeate
concentrate
feed water
concentrate
permeate
feed water
permeate
concentrate
feed water
permeate
concentrate
feed water
permeate

9.43
8.95
9.06
9.30
9.03
9.13
9.49
9.00
9.21
9.56
9.08
9.65
9.10
9.10
9.50
9.12
9.20
9.14
9.49
9.24
9.57
9.16
9.21
9.51
9.12
9.22
9.41
Acceptable
Precision
Duplicate
9.44
9.01
9.12
9.26
9.04
9.19
9.44
9.07
9.19
9.58
9.10
9.60
9.11
9.00
9.52
9.11
9.20
9.12
9.52
9.24
9.52
9.15
9.21
9.51
9.12
9.20
9.42
Precision
(continued)
Percent
Precision
2%
14%2
14%2
9%
2%
14%2
12%2
16%2
5%
5%
5%
12%2
2%
23%2
5%
2%
0%
5%
7%
0%
12%2
2%
0%
0%
0%
5%
2%
10%
Temperature duplicates were taken twice weekly and only on the feed water.
Exceeded the precision limit of 10%, as defined in Table 3-7.
                                                89

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Table 4-28:
Date
4/26/04
4/28/04
4/30/04
5/2/04
5/7/04
5/9/04
5/10/04
5/12/04
5/14/04
5/16/04
5/18/04
5/19/04
5/20/04
5/21/04
5/23/04
5/24/04
5/26/04

TDS Analytical Precision
Sample Location
permeate
feed water
concentrate
permeate
concentrate
permeate
feed water
concentrate
permeate
feed water
permeate
feed water
permeate
concentrate
permeate
concentrate
permeate

Sample TDS
(mg/L)
<10
150
270
12
240
<10
130
260
16
140
24
140
25
230
45
230
34

Duplicate TDS
(mg/L)
<10
140
260
13
250
14
130
250
12
140
25
130
26
230
37
230
34
Acceptable Precision
Percent
Precision
0%
5%
3%
6%
3%
24%
0%
3%
20%
0%
3%
5%
3%
0%
14%
0%
0%
30%
90

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Table 4-29:  Daily Conductivity Precision Analysis


Date
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/23/04
5/24/04
5/25/04
5/26/04
5/26/04

1 The duplicate
logbook.


Sample Location
permeate
concentrate
feed water
permeate
concentrate
feed water
permeate
permeate
concentrate
feed water
permeate
feed water
permeate
concentrate
concentrate1
permeate
concentrate
feed water
feed water
concentrate
permeate
feed water
permeate
concentrate
feed water
permeate
permeate
concentrate
feed water
permeate
permeate

conductivity value was taken

Sample
Conductivity
(umoh/cm)
6.7
554
232
11.3
412
245
11.1
11.1
426
245
16.2
237
22.8
437
417
25.8
420
241
241
398
39.2
234
41.3
378
228
58.3
58.3
368
230
76.5
76.5

on the concentrate

Duplicate
Conductivity
(umoh/cm)
6.7
556
230
11.5
431
247
12.2
12.1
425
244
16.4
235
22.7
436
438
25.8
421
240
241
406
39.6
234
41.4
380
229
58.2
58.4
369
230
76.6
76.8
Acceptable Precision
water and not the feed water,


Percent
Precision
0.00%
0.25%
0.61%
1.24%
3.19%
0.57%
6.68%
6.10%
0.17%
0.29%
0.87%
0.60%
0.31%
0.16%
3.47%
0.00%
0.17%
0.29%
0.00%
1.41%
0.72%
0.00%
0.17%
0.37%
0.31%
0.12%
0.12%
0.19%
0.00%
0.09%
0.28%
10%
as indicated in the

                                          91

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Table 4-30: Daily Total Arsenic Precision Analysis
      Date
Sample Location
Sample Arsenic    Duplicate Arsenic
Precision
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04

permeate
concentrate
feed water
permeate
concentrate
feed water
permeate
concentrate
feed water
permeate
feed water
permeate
concentrate
feed water
permeate
concentrate
feed water
concentrate
permeate
feed water
permeate
concentrate
feed water
permeate
concentrate
feed water
permeate

< 1.0
38
13
< 1.0
26
14
< 1.0
28
15
< 1.0
13
< 1.0
27
13
< 1.0
25
13
25
< 1.0
14
< 1.0
26
14
< 1.0
25
15
1.2

< 1.0
36
12
< 1.0
26
14
< 1.0
27
14
< 1.0
13
< 1.0
26
14
< 1.0
24
13
26
< 1.0
14
< 1.0
24
14
< 1.0
24
15
< 1.0
Acceptable Precision
0%
4%
6%
0%
0%
0%
0%
3%
5%
0%
0%
0%
3%
5%
0%
3%
0%
3%
0%
0%
0%
6%
0%
0%
3%
0%
0%
30%
4.6.2 Accuracy

Arsenic Speciation and Analysis
Total arsenic samples were collected daily according to EPA Method 200.8.  Additional arsenic
samples were collected weekly for As3+ and dissolved arsenic.  The field speciation columns
were provided by  NSF.  QA/QC  evaluations  of  the  speciation  columns  using known
concentrations  of As3+ and As5+ were conducted by the NSF laboratory prior to the verification
test.

One concentrate  sample (collected May  24,  2004) indicated higher  As3+ than total arsenic.
While it is not  reasonable for a single species of arsenic to have a higher concentration than the
total, it is  further perplexing to measure a detectable concentration of As3+ as this water source is
chlorinated.  There  is currently no explanation  for these results.  Furthermore, 10% of the
samples showed slightly higher dissolved arsenic concentrations than total arsenic.   However,
these samples  were just slightly  higher than the  total  arsenic  and primarily found  in  the
concentrate samples.  On April 26, 2004 the dissolved arsenic concentration in the concentrate
was  16 |ig/L, with a total arsenic of 13 |ig/L, and on May 7 the  dissolved arsenic concentration in
the concentrate was  14 |ig/L, with a total arsenic of 12 |ig/L.   On May 24, 2004, the dissolved
                                            92

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arsenic of  1.1 |ig/L with a total arsenic of <1.0 |ig/L. Accuracy checks for arsenic samples
performed by the MWH Laboratory were within the acceptable limits outlined in Table 3-8.

Other Laboratory Parameters
Accuracy checks performed by the MWH Laboratory for all samples analyzed by the laboratory
were within the acceptable limits outlined in Table 3-8.

pH Meter
The pH meter was  calibrated daily using certified pH solutions (4.0, 7.0 and  10.0) from Hach.
Analyses were made daily according to Standard Method 4500-H+B.

Temperature
Table 3-7  indicates that temperature was to be  verified weekly against a NIST-certified
thermometer. Since the feed water temperature was measured twice daily using a NIST-certified
thermometer, no accuracy checks were necessary.

Alkalinity
Two sets of four known samples were analyzed during the verification test to verify the accuracy
of the onsite test method. The accuracy checks are discussed in additional detail in Section 4.6.3
with corresponding data provided in Table 4-32, with  all results being within the acceptable
accuracy range of + 30% recovery.

Hardness
Two sets of four known samples were analyzed during the verification test to verify the accuracy
of the onsite test method. The accuracy checks are discussed in additional detail in Section 4.6.3
with corresponding data provided in Table 4-32, with  all results being within the acceptable
accuracy range of + 30% recovery.

Turbidity Instrumentation
The turbidity meter was calibrated each day the instrument was in use.  Calibrations were made
using both primary and secondary standards provided  by Hach.   Each calibration was  also
checked against standards in the anticipated turbidity range  of the samples (0.1, 0.5  and 5 NTU).

Conductivity Meter
The handheld conductivity meter was used according to StandardMethod2510 B.  A three-point
calibration  with certified conductivity solutions (184, 1000, and 1990 umoh/cm) was made  each
day the meter was in use.

Chlorine Meter
The chlorine meter  was checked for accuracy through the use of known spike samples provided
by Hach with the Hach 8167 method for total chlorine and Hach 8021 method for  free chlorine,
at a frequency of three times during the verification testing.  The accuracy of the  free and  total
chlorine  spikes  is  discussed in  additional  detail in Section  4.6.3 with  corresponding  data
provided in Table  4-32,  with all  results being within the  acceptable accuracy range of +  30%
recovery.
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Flow Monitoring
The M-15,000 RO Treatment System was equipped with panel mounted flow meters to read the
permeate and concentrate flow rates and were checked daily using the "calibrated container and
stopwatch" method.  The flow meters appeared to be  accurate according to this method of
calibration, with an average accuracy of 98% for both the concentrate and permeate flow rates.
The flow meters were not designed to allow adjustment or calibration, so the differences (when
present) were recorded, however, no adjustments could be made to "calibrate" the flow meters.
Table 4-31 presents the results of the daily permeate and concentrate flow rate checks and the
percent accuracy of the panel mounted flow meters.

Pressure Gauges
Watts Premier indicated that the pressure gauges installed were factory-calibrated; no additional
accuracy checks were performed.
Table 4-31:




Date
4/26/04
4/27/04
4/28/04
4/29/04
4/30/04
5/1/04
5/2/04
5/7/04
5/8/04
5/9/04
5/10/04
5/11/04
5/12/04
5/13/04
5/14/04
5/15/04
5/16/04
5/17/04
5/18/04
5/19/04
5/20/04
5/21/04
5/22/04
5/23/04
5/24/04
5/25/04
5/26/04



Daily Permeate and Concentrate Flow

Known
Permeate
Flow Rate
(gpm)1
14.00
13.50
13.00
12.80
9.50
8.50
8.25
11.50
11.50
11.00
10.75
10.00
9.50
13.00
12.75
12.50
13.00
13.00
13.00
12.50
12.50
12.25
12.00
12.00
12.00
12.00
12.25




Measured
Permeate
Flow
Rate (gpm)
14.00
13.50
12.50
12.50
9.00
8.50
8.25
10.25
11.50
11.00
10.50
10.00
9.50
9.25
12.50
12.50
13.00
13.00
13.00
12.50
12.50
12.50
12.00
12.00
12.00
12.00
12.50
Average
Minimum
Maximum
% Accuracy
of Panel
Mounted
Permeate
Flow Meter
100%
100%
96%
98%
95%
100%
100%
89%
100%
100%
98%
100%
100%
71%
98%
100%
100%
100%
100%
100%
100%
98%
100%
100%
100%
100%
98%
98%
71%
100%
Rate Checks

Known
Concentrate
Flow Rate
(gpm)
6.50
6.00
6.00
5.20
8.50
8.50
8.50
11.50
11.75
11.00
10.75
9.75
9.50
12.50
12.50
12.50
12.50
13.00
13.50
12.50
12.50
12.75
12.50
12.50
12.50
13.00
12.50



(Calibration)

Measured
Concentrate
Flow Rate
(gpm)
6.50
6.00
6.00
5.25
8.50
8.50
8.25
10.25
11.75
11.00
10.75
9.50
9.50
8.50
12.50
12.50
12.50
13.00
13.00
12.50
12.50
12.50
12.50
12.50
12.50
13.00
12.50
Average
Minimum
Maximum
% Accuracy
of Panel
Mounted
Concentrate
Flow Meter
100%
100%
100%
99%
100%
100%
97%
89%
100%
100%
100%
97%
100%
68%
100%
100%
100%
100%
96%
100%
100%
98%
100%
100%
100%
100%
100%
98%
68%
100%
                                           94

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Table 4-32:
Date
5/2/04
6/16/04
5/24/04

Date
5/2/04
5/16/04

Spike Data for Free and Total Chlorine,
Free Chlorine
Spike (mg/L) Value (mg/L) Accuracy
0
0.25
0.50
0.75
0
0.25
0.50
0.75
0
0.25
0.50
0.75

0
0.25
0.49
0.74
0
0.25
0.50
0.75
0
0.25
0.49
0.74
Acceptable Accuracy
Hardness
Spike (mg/L) Value (mg/L)
0
1.0
2.0
3.0
0
1.0
2.0
3.0

0
1.0
2.0
3.0
0
1.1
2.1
3.2
Acceptable Accuracy
0.0%
0.0%
2.0%
1.3%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
2.0%
1.3%
30%
Accuracy
0.0%
0.0%
0.0%
0.0%
0.0%
9.1%
4.8%
6.3%
30%
Hardness, and Alkalinity
Total Chlorine
Spike (mg/L) Value (mg/L)
0
0.25
0.50
0.75
0
0.25
0.50
0.75
0
0.25
0.50
0.75
0.02
0.23
0.45
0.72
0
0.24
0.50
0.75
0
0.24
0.49
0.73
Acceptable Accuracy
Spike (mg/L)
0
3.0
5.5
7.0
0
3.0
5.5
7.0
Alkalinity
Value (mg/L)
0
3.0
5.5
8.0
0.0
2.5
5.0
7.4
Acceptable Accuracy
Accuracy
0.0%
8.0%
10.0%
4.0%
0.0%
4.0%
0.0%
0.0%
0.0%
4.0%
2.0%
2.7%
30%
Accuracy
0.0%
0.0%
0.0%
13%
0.0%
17%
9.1%
5.4%
30%
4.6.3  Off-Site Analysis of Samples

4.6.3.1 Inorganic Samples

Inorganic samples were collected in accordance with the Standard Methods and EPA methods
listed in Table 3-6.  All samples were stored in a refrigerator, held at 4°C until shipment to the
off-site analytical lab (MWH Laboratories).   Samples were shipped with  chain-of-custody in
coolers packed with blue ice. All samples were analyzed within the required  holding times.

4.6.3.2 Organic Samples

TOC was sampled six times throughout the verification testing.  All samples were collected in
amber glass bottles, stored at 4°C, and shipped in coolers packed with blue ice.  All samples
were analyzed according to Standard Method 53IOC within the required  holding times.   All
results were below the MDL of 0.50 mg/L. All spikes,  duplicates, and precision analyses were
within the required testing parameters, as presented in Table 3-8.
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4.6.4  Completeness

Calculation of data completeness was made for on-site water quality measurements and MWH
Laboratory  water  quality  measurements,  as  explained  in  Section  3.12.4.4.   During  the
verification test,  duplicate samples were collected in a rotating manner (i.e., duplicates were
taken of the  feed water during one  round of duplicate analysis, then permeate samples, and
finally concentrate samples).  Based  on the completeness goals defined in Table 3-11 and the
completeness results in Table 4-33, all parameters were within the stated completeness goals.

Table 4-33: Completeness
Parameter
    Proposed1             Actual
Results   Duplicates   Results   Duplicates
 Completeness (%)
Results   Duplicates
 Completeness Goal
Results   Duplicates
Arsenic (Total)
Arsenic
(Speciated)
pH
Silica
Fluoride
Chromium
Vanadium
TOC
Chloride
Iron
Manganese
Sulfate
Temperature
Alkalinity
Hardness
Turbidity
Conductivity
Barium
Calcium
TSS
SDI
TDS
Free Chlorine
Total Chlorine
81

15
81
15
15
15
15
15
15
15
15
15
54
15
15
15
162
15
15
15
1
81
36
36
27

NA
27
5
5
5
5
5
5
5
5
5
10
5
5
5
33
5
5
5
1
17
9
9
81

15
81
15
15
15
15
15
15
15
15
15
54
15
15
15
162
15
15
15
1
81
36
36
27

NA
27
5
5
5
5
5
5
5
5
5
8
5
5
5
31
5
5
5
1
17
17
17
100%

100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%

NA
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
80%
100%
100%
100%
94%
100%
100%
100%
100%
100%
>100%
>100%
95%

90%
95%
90%
90%
90%
90%
90%
90%
90%
90%
90%
95%
90%
90%
90%
95%
90%
90%
90%
80%
95%
90%
90%
90%

NA
90%
80%
80%
80%
80%
80%
80%
80%
80%
80%
80%
80%
80%
80%
90%
80%
80%
80%
80%
90%
90%
90%
  Based on 27 days of testing.
  Based on completeness guidelines outlined in Table 3-11.

4.6.5 NSF Field Inspection

On May 13, 2004,  NSF  conducted a field inspection  of the verification test and found the
practices in  place on-site to be in accordance with the PSTP that was approved prior to beginning
the testing.
                                            96

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                                      Chapter 5
                                     References

The following references were used in the preparation of this report:

Methods for Chemical Analysis of Water and Wastes (MCAWW) EPA/600/4-79-202 - Revised
March 1983.

Methods for Determination of Organic Compounds in Drinking Water - EPA/600/4-8 8/03 9-
December 1988 (Revised July 1991).

Standard Methods for the Examination of Water and Wastewater.  1999. 20th edition. APHA,
AWWA, and WEF, Washington D.C.

U.S. EPA/NSF International.  EPA/NSF ETV Protocol for Equipment Verification Testing for
Arsenic Removal, September 2003.

U.S. EPA/NSF International.  EPA/NSF ETV Protocol for Equipment Verification Testing for
Removal of Inorganic Constituents, April 2002.
                                         97

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                                       Chapter 6
                                   Vendor Comments

Watts Premier submitted the following comments concerning the ETV test and report.  These
statements were not validated in the verification test and are the opinion of Watts Premier:

"4.2.1 General Operational Performance

Just prior to the commencement of the ETV project and installation of the M-15,000 RO system
it was discovered that the water entering the reverse osmosis unit would be chlorinated. At this
time based upon the water parameters that were provided, and given the consideration that this
would be a one month duration test, a 4" x 20" carbon filter was used as pre-filtration for the RO
unit. It was agreed that under these conditions this testing would certainly provide a "worst case"
arsenic reduction test protocol for the M-15,000 RO unit.

Seven days in to the arsenic reduction testing of the RO unit, the motor on the M-15,000 seized.
It was discovered during the replacement of the pump that the pre filter to the M-15,000 unit was
completely plugged. Upon further investigation by MWH field staff, it was discovered that the
periodic  operation of the CVWD Well 7802  introduced  a significant slug of solids with each
start-up, which then plugged the carbon pre-filter.  With the plugging of the carbon prefilter, the
pump seized due to loss of water to the motor.

Once the pump was replaced and the pre filtration switched to a 20 micron sediment filter, RO
system operation stabilized.

Due to the tight time line and the relatively short duration of the test, Watts  Premier suggested
the use of a sediment pre filter to the RO unit.  With only a few weeks remaining in the project
testing phase, this chlorine contact on the RO membrane would represent an even further "worst-
case" evaluation of reduction capabilities.  This would provide valuable information to Watts
Premier and the industry in regards to the operation of the M-15,000 RO unit.

Looking at several parameters with in this report, including feed water flow rate decreasing, flux
reduction, increase in permeate conductivity it is  evident that the chlorine did in fact have a
negative effect on the overall reduction capabilities of the membranes.  Permanent installation
and  operation of the Ml5,000 unit would include a thorough  review of the water system
operation, which  would have revealed the solids that CVWD Well 7802  introduced in to  the
system. Based upon this information, and the presence of chlorine, permanent installation of an
M-15,000 would  include proper filtration prior to the M  series reverse osmosis unit to remove
the chlorine and sufficient sediment filtration capabilities  to efficiently handle the frequent slug
of solids that the CVWD Well 7802 discharged to the water treatment system.

4.3 Task 2: Cleaning Efficiency

M series of RO units are available for systems that feed both in to a pressure tank, as well as a
float tank apparatus. Each system is designed to go through a self initiated rinse cycle of the RO
membranes. This rinse cycle occurs at either the unit shut down for units operating on short duty
                                           98

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cycles or on timed periodic schedule for those systems operating on extended duty cycles.  This
cleaning cycle is used in order to remove solids and other salts from the membrane, therefore
prolonging the life of each membrane module.  During normal operation where water is being
discharged to a permanent tank, this flushing procedure would commence each time the tank is
filled, and the M-15,000 system goes  in to standby  mode. During this ETV test, the M-15,000
unit was on continuously for the duration of the testing. Based upon this quantity of water being
treated,  this  flushing cycle would have  occurred  more frequently under normal  operation
procedures than what was conducted during this evaluation.

Based upon the results obtained through this ETV testing protocol, the M series of commercial
reverse  osmosis systems has proven to be  a viable means of processing water for the intent of
domestic or industrial use.

Watts Premier would like to thank the hard work of all  participants from MWH and NSF in
completing this ETV  project.   All  of their  hard work  on this project  has been  greatly
appreciated."
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