September 2005
NSF05/14b/EPADWCTR
EPA600/R-05/122
Environmental Technology
Verification Report
Removal of Chemical Contaminants in
Drinking Water
EcoWater Systems Incorporated
ERO-R450E Drinking Water Treatment
System
Prepared by
NSF International
Under a Cooperative Agreement with
U.S. Environmental Protection Agency
-------
-------
THE ENVIRONMENTAL TECHNOLOGY VERIFICATION
PROGRAM
U.S. Environmental Protection Agency
NSF International
ETV Joint Verification Statement
TECHNOLOGY TYPE:
APPLICATION:
PRODUCT NAME:
COMPANY:
ADDRESS:
PHONE:
EMAIL:
POINT-OF-USE DRINKING WATER TREATMENT SYSTEM
REMOVAL OF CHEMICAL CONTAMINANTS IN DRINKING
WATER
ECOWATER SYSTEMS ERO-R450E
ECOWATER SYSTEMS, INC.
1890 WOODLANE DRIVE
WOODBURY,MN 55125
800-808-9899
INFO(%ECOWATERCOM
NSF International (NSF) manages the Drinking Water Systems (DWS) Center under the U.S.
Environmental Protection Agency's (EPA) Environmental Technology Verification (ETV) Program. The
DWS Center recently evaluated the performance of the EcoWater Systems ERO-R450E point-of-use
(POU) drinking water treatment system. NSF performed all of the testing activities, and also authored the
verification report and this verification statement. The verification report contains a comprehensive
description of the test.
EPA created the 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 05/14b/EPADWCTR The accompanying notice is an integral part of this verification statement. September 2005
VS-i
-------
ABSTRACT
The EcoWater Systems ERO-R450E POU drinking water treatment system was tested for removal of
aldicarb, benzene, cadmium, carbofuran, cesium, chloroform, dichlorvos, dicrotophos, fenamiphos,
mercury, mevinphos, oxamyl, strontium, and strychnine. The ERO-R450E employs a reverse osmosis
(RO) membrane and activated carbon filters to treat drinking water. Treated water is stored in a 3.1-
gallon capacity storage tank. The system was first tested with only the RO membrane component in
place. The target challenge concentration for each chemical for the RO membrane tests was 1 mg/L.
Following the RO membrane challenges, the post-membrane carbon filter component was challenged
alone with each organic chemical the RO membrane did not remove to below 30 |o,g/L. The carbon filter
was also challenged with cesium and mercury because the membranes did not remove these two
substances as well as total dissolved solids (TDS) in general. The target challenge concentration for the
carbon filter tests was the maximum effluent level measured during the RO membrane tests.
A total of 20 RO membrane components were tested, divided into ten pairs. Each pair of membranes was
tested with only one of the ten organic chemicals because of concern that a chemical could compromise
the integrity of the membrane or membrane seals. One pair of RO membrane components was also
challenged with the inorganic chemicals. Each RO membrane chemical challenge was conducted over a
one-day period. Influent and effluent samples were collected during the operation period, and also the
next morning. The post-membrane carbon filter challenges were conducted over a 15-hour duration.
Two filters were tested for each chemical challenge, and each pair was only used for one challenge.
Influent and effluent samples were collected at the beginning, middle, and end of the challenge period.
The ERO-R450E as a whole, considering both the RO membrane challenge and post-membrane carbon
filter challenge results combined, reduced all of the challenge chemicals but cesium by 94% or more.
TECHNOLOGY DESCRIPTION
The following technology description was provided by the manufacturer, and has not been verified.
The ERO-R450E is a three-stage POU drinking water treatment system, employing an RO membrane,
and activated carbon filters both upstream and downstream of the membrane. The system includes a 3.1-
gallon maximum capacity pressurized bladder tank for storing the treated water, and a faucet to mount on
the kitchen sink. The influent water first passes through a carbon filter designed to remove chlorine and
particulate matter, such as rust and silt. The second stage of treatment is the reverse osmosis membrane,
which reduces a wide variety of contaminants. The permeate water is sent to the storage tank. When the
user opens the faucet, the partially treated water leaves the storage tank, passes through a second carbon
filter to remove organic chemicals and any taste and odor chemicals, and then exits the faucet.
When the flow of water into the system is started, treated water will be continually produced until the
storage tank is nearly full. At that time, the water pressure in the tank activates an automatic shut-off
device, stopping the flow of water through the system. After a portion of the water is dispensed from the
storage tank, the shut-off device deactivates, allowing water to again flow into the system until the storage
tank is nearly full.
NSF 05/14b/EPADWCTR The accompanying notice is an integral part of this verification statement. September 2005
VS-ii
-------
VERIFICATION TESTING DESCRIPTION
Test Site
The testing site was the Drinking Water Treatment Systems Laboratory at NSF in Ann Arbor, Michigan.
A description of the test apparatus can be found in the test/QA plan and verification report. The testing
was conducted November 2004 through March 2005.
Methods and Procedures
Verification testing followed the procedures and methods detailed in the Test/QA Plan for Verification
Testing of the EcoWater Systems ERO-R450E Point-of-Use Drinking Water Treatment System for
Removal of Chemical Contamination Agents. Because any contamination event would likely be short-
lived, the challenge period for each chemical lasted only one day. Long-term performance over the life of
the membrane was not evaluated.
The system was first tested with only the RO membrane component in place. The complete ERO-R450E
system, including the storage tank, was used for the RO membrane challenges, but the carbon filters were
removed, leaving empty housings. A total of 20 RO membranes were challenged with the chemicals in
Table 1. The target challenge concentration for each chemical was 1 mg/L. The 20 membrane test units
were divided into ten pairs. Each pair was tested with only one of the ten organic chemicals because of
concern that a chemical, especially benzene or chloroform, could compromise the integrity of the
membrane or membrane seals. One pair of RO membrane components was also challenged with the
inorganic chemicals. The inorganic chemical challenges were conducted prior to the organic chemical
challenges to eliminate the possibility of damage to the membranes that could bias the inorganic chemical
test results. The reduction of TDS was also measured during the challenges to evaluate whether any
organic chemicals damaged the membrane material or membrane seals.
Table 1. Challenge Chemicals
Organic Chemicals Inorganic Chemicals
Aldicarb Cadmium Chloride
Benzene Cesium Chloride (nonradioactive isotope)
Carbofuran Mercuric Chloride
Chloroform Strontium Chloride (nonradioactive isotope)
Dicrotophos
Dichlorvos
Fenamiphos
Mevinphos
Oxamyl
Strychnine
Prior to challenge testing, the RO membrane components were service-conditioned for seven days by
feeding the systems the test water without any chemical spikes. After completion of the conditioning
period, the membranes were subjected to a TDS reduction test using sodium chloride to verify that they
were operating properly.
Each RO membrane chemical challenge was conducted over a one-day period. The systems were
operated for six tank-fill periods, and then were allowed to rest overnight. Influent and effluent samples
were collected at start-up, after the 3rd tank fill, after the 5th tank fill, and the next morning after the
membranes rested under pressure overnight.
NSF 05/14b/EPADWCTR The accompanying notice is an integral part of this verification statement. September 2005
VS-iii
-------
Following the RO membrane challenges, the post-membrane carbon filters were challenged with the
chemicals that the RO membranes did not remove to below 30 |o,g/L. The carbon filter was also
challenged with cesium and mercury because the membranes did not remove these two substances as well
as total dissolved solids (TDS) in general. The filters were attached to a separate manifold that was of the
same design as the manifold in the full RO system. The pre-membrane carbon filter was not tested
because it is only designed to remove chlorine to protect the RO membrane. Two carbon filters were
tested for each chemical challenge, and each filter was only used for one challenge. The target challenge
concentrations were the maximum effluent levels measured during the RO membrane tests.
Prior to testing, each carbon filter was service-conditioned by feeding water containing chloroform to
simulate the possible contaminant loading on the carbon halfway through the filter's effective lifespan.
The target chloroform concentration was 300 ± 90 |o,g/L, which is the influent challenge concentration for
the VOC reduction test in NSF/ANSI Standard 53 (chloroform is the surrogate challenge chemical for the
test). The filters were operated at a flow rate of 0.5 gallons per minute (gpm) for 375 gallons (EcoWater
System's design capacity for the filter is 750 gallons).
The post-membrane carbon filter challenges were 15 hours in duration. Influent and effluent samples
were collected at the beginning, middle, and end of the challenge period. The carbon filters were
operated on an "on/off operation cycle where the "on" portion was the time required to empty the system
storage tank when full, and the "off portion was the time required to fill the storage tank.
VERIFICATION OF PERFORMANCE
The results of the RO membrane challenges are presented in Table 2. The RO membrane treatment
process removed 94% or more of all challenge chemicals except cesium and mercury. The membrane
removed 82% of cesium, and only 9% of the mercury challenge.
Table 2. RO Membrane Challenge Data
Mean Influent Mean Effluent Percent
Chemical Qg/L) (|ag/L) Reduction (%)
Cadmium
Cesium
Mercury
Strontium
Aldicarb
Benzene
Carbofuran
Chloroform
Dichlorvos
Dicrotophos
Fenamiphos
Mevinphos
Oxamyl
Strychnine
960
930
1100
960
1000
980
1100
1100
1300
1100
930
1200
980
1100
33
170
1000
33
20
7.1
19
61
69
57
4
46
10
10
97
82
9
97
98
>99
98
94
95
95
>99
96
99
>99
The TDS reduction by each membrane component for all challenge tests was 87% or higher. The effluent
TDS levels for some of the chemical challenges rose from one sample point to the next over the challenge
period, but no TDS levels were significantly higher than the maximum TDS levels measured during TDS
reduction tests conducted on each unit after conditioning. Thus, the rising TDS levels likely do not
NSF 05/14b/EPADWCTR The accompanying notice is an integral part of this verification statement. September 2005
VS-iv
-------
indicate that the membrane components were becoming significantly compromised due to exposure to the
chemicals. The increase may have been due to the challenge protocol design. The challenges began with
empty storage tanks, so there was no back-pressure on the membranes when the start-up samples, which
all had the lowest observed TDS levels, were collected. Most of the challenge chemical levels were also
lowest in the start-up samples. The rest of the samples were collected after the membranes had been
operating facing back-pressure from the storage tanks. RO membranes perform better without back-
pressure, so the higher TDS levels are likely more indicative of the performance of the RO system under
normal operating conditions.
The post-membrane carbon filter components were challenged with chloroform, dichlorvos, dicrotophos,
and mevinphos based on the criteria that the RO membrane challenge effluents were above 30 |og/L. The
carbon filters were also challenged with cesium and mercury. The target challenge levels were the
maximum effluent levels measured during the RO membrane challenges. The carbon filters were
operated at 1.15 gpm on an operating cycle where the "on" portion was five minutes and eleven seconds,
and the "off portion was one hour and ten minutes.
The carbon challenge results are shown below in Table 3. Note that the percent reduction of dicrotophos
was limited by the detection limit for the chemical. The carbon filter removed 89% or more of all of the
challenge chemicals but cesium, which was effectively not removed at all by the carbon.
Table 3. Post-Membrane Carbon Filter Challenge Data
Mean Influent Mean Effluent Percent
Chemical (|ag/L) (|ag/L) Reduction (%)
Cesium
Mercury
Chloroform
Dichlorvos
Dicrotophos
Mevinphos
230
760
100
100
90
40
220
35
0.7
3.9
ND(10)
2.1
4.3
95
>99
96
89
95
The RO membrane and carbon challenge data combined shows that the two treatment technologies
working in concert within the ERO-R450E system removed 97% or more of all challenge chemicals but
cesium.
Complete descriptions of the verification testing results are included in the verification report.
QUALITY ASSURANCE/QUALITY CONTROL (QA/QC)
NSF ETV and QA staff monitored the testing activities to ensure that the testing was in compliance with
the test plan. NSF also conducted a data quality audit of 100% of the data. Please see the verification
report referenced below for more QA/QC information.
NSF 05/14b/EPADWCTR The accompanying notice is an integral part of this verification statement. September 2005
VS-v
-------
Original signed by Andrew Avel, 10/25/05 Original signed by Robert Ferguson, 11/07/05
Andrew P. Avel Date Robert Ferguson Date
Acting Director Vice President
National Homeland Security Research Center Water Systems
United States Environmental Protection NSF International
Agency
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 test protocol, the verification statement, and the verification report (NSF report # NSF
04/14b/EPADWCTR) are available from the following sources:
(NOTE: Not all of the appendices are included in the verification report. The 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.nsforg/etv/dws/dws_reports.html, and from
http://www.nsforg/etv/dws/dws_project_documents.html (electronic copy)
EPA web site: https://www.epa.gov/etv (electronic copy)
NSF 05/14b/EPADWCTR The accompanying notice is an integral part of this verification statement. September 2005
VS-vi
-------
September 2005
Environmental Technology Verification Report
Removal of Chemical Contaminants in Drinking Water
EcoWater Systems Incorporated
ERO-R450E Drinking Water Treatment System
Prepared by:
NSF International
Ann Arbor, Michigan 48105
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
-------
Notice
The U.S. Environmental Protection Agency (USEPA) through its Office of Research and
Development has financially supported and collaborated with NSF International (NSF) under
Cooperative Assistance 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
USEPA, and recommended for public release.
11
-------
Foreword
The U.S. Environmental Protection Agency (USEPA) 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, USEPA'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 USEPA's Office of Research and Development to assist
the user community and to link researchers with their clients.
Sally Gutierrez, Director
National Risk Management Research Laboratory
in
-------
Table of Contents
Verification Statement [[[ VS-i
Title Page [[[ i
Notice [[[ ii
Foreword [[[ iii
Table of Contents [[[ iv
List of Tables [[[ vi
List of Figures [[[ vi
Abbreviations and Acronyms [[[ vii
Acknowlegements [[[ viii
Chapter 1 Introduction
1 . 1 Environmental Technology Verification (ET V) Program Purpose and Operation
12 Purpose of Verification
1 3 Development of Test/Quality Assurance (QA) Plan
1 . 4 Challenge Chemical s
1 . 5 Testing Participants and Responsibilities
1 5 1 NSF International
152 EcoWater Systems Inc
1.5.3 U.S. Environmental Protection Asencv
1
.... 1
1
1
7
7
9
3
3
Chapter 2 Equipment Description [[[ 4
2.1 Principals of Operation [[[ 4
2.1.1 Activated Carbon [[[ 4
2.1.2 RO Membrane [[[ 4
2.2 Equipment Capabilities [[[ 4
2.3 System Components [[[ 4
2.4 System Operation [[[ 5
2.5 Rate of Waste Production [[[ 6
-------
3.2.4.2 Post-Membrane Carbon Filter Test Units 13
3.2.5 Challenge Protocols and Sampling Plans 13
3.2.5.1 TDS Reduction System Performance Check 13
3.2.5.2 RO Membrane Challenge Testing 13
3.2.5.3 Post-Membrane Carbon Filter Challenge Testing 15
3.3 Analytical Methods 17
3.3.1 Water Quality Analytical Methods 17
3.3.2 Challenge Chemical Analytical Methods 18
Chapter 4 Results and Discussion 20
4.1 RO membrane Conditioning 20
4.1.1 RO Membrane System Operation Data 20
4.2 Post-Membrane Carbon Filter Conditioning 20
4.3 TDS Reduction System Performance Check 21
4.4 RO Membrane Chemical Challenges 21
4.4.1 Inorganic Chemicals Challenges 21
4.4.2 Organic Chemical Challenges 23
4.5 Post-Membrane Carbon Filter Challenges 25
4.6 Conclusions 26
Chapters QA/QC 27
5.1 Introduction 27
5.2 Test Procedure QA/QC 27
5.3 Sample Handling 27
5.4 Analytical Methods QA/QC 27
5.5 Documentation 28
5.6 Data Review 28
5.7 Data Quality Indicators 28
5.7.1 Representativeness 28
5.7.2 Accuracy 28
5.7.3 Precision 29
5.7.4 Completeness 30
5.7.4.1 Number of Systems Tested 30
5.7.4.2 Water Chemistry Measurements 30
5.7.4.3 Challenge Chemicals 31
Chapter 6 32
-------
Appendix
Appendix A Conditioning and Chemical Challenges Data Tables
List of Tables
Table 1-1. Challenge Chemicals 2
Table 3-1. Challenge Chemicals 9
Table 3-2. Summary of Sampling Plan for RO Membrane Challenges 16
Table 3-3. Summary of Sampling Plan for Post-Membrane Carbon Filter Challenges 17
Table 3-4. QC Limits and Method Reporting Limits for Analyses 18
Table 4-1. RO Membrane System Operation Data 20
Table 4-2. Post-Membrane Carbon Filter Conditioning Influent Water Chemistry 21
Table 4-3. RO Membrane Inorganic Chemical Reduction Data 22
Table 4-4. Inorganic Chemical Challenge Reject Water Data 23
Table 4-5. RO Membrane Organic Chemical Challenge Data 23
Table 4-6. TDS Reduction Data for Organic Chemical Challenges 24
Table 4-7. Organic Chemical Challenge Reject Water Data 24
Table 4-8. Post-Membrane Carbon Filter Challenge Data 25
Table 4-9. Combined Performance of RO Membrane and Post-Membrane Carbon Filter 26
Table 5-1. Completeness Requirements 30
List of Figures
Figure 2-1. Photograph of the ERO-R45 OE 5
Figure 2-2. Schematic Diagram of the ERO-R450E 6
Figure 3-1. RO Membrane Systems Installed at Test Station 14
Figure 3-2. Post-Membrane Carbon Filters Installed at Test Station 16
VI
-------
Abbreviations and Acronyms
ANSI
°C
DWS
DWTS
ETV
°F
GC/MS
gpd
gpm
HC1
HPLC
ICP/MS
L
LFB
LFM
mg
mL
NaOH
ND
NRMRL
NSF
NTU
POE
POU
psi
QA
QC
QA/QC
RO
RPD
RSD
SOP
IDS
TOC
Hg
USEPA
VOC
American National Standards Institute
Degrees Celsius
Drinking Water Systems
Drinking Water Treatment Systems
Environmental Technology Verification
Degrees Fahrenheit
Gas Chromatography/Mass Spectrometry
Gallons Per Day
Gallons Per Minute
Hydrochloric Acid
High Pressure Liquid Chromatography
Inductively Coupled Plasma - Mass Spectrometry
Liter
Laboratory Fortified Blank
Laboratory Fortified Matrix
Milligram
Milliliter
Sodium Hydroxide
Non-detect
National Risk Management Research Laboratory
NSF International (formerly known as National Sanitation Foundation)
Nephelometric Turbidity Unit
Point-of-Entry
Point-of-Use
Pounds per Square Inch
Quality Assurance
Quality Control
Quality Assurance/Quality Control
Reverse Osmosis
Relative Percent Difference
Relative Standard Deviation
Standard Operating Procedure
Total Dissolved Solids
Total Organic Carbon
Microgram
U. S. Environmental Protection Agency
Volatile Organic Chemical
vn
-------
Acknowledgments
NSF 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.
The manufacturer of the equipment was:
EcoWater Systems Incorporated
1890 Woodlane Drive
Woodbury, MN 55125
NSF wishes to thank the members of the expert technical panel for their assistance with
development of the test plan.
Vlll
-------
Chapter 1
Introduction
1.1 Environmental Technology Verification (ETV) Program Purpose and Operation
The U.S. Environmental Protection Agency (USEPA) has created the 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 that are responsive to the needs of stakeholders, by
conducting field or laboratory testing, collecting and analyzing data, and by 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 USEPA has partnered with NSF International (NSF) under the ETV Drinking Water
Systems (DWS) Center to verify performance of drinking water treatment systems that benefit
the public and small communities. It is important to note that verification of the equipment does
not mean the equipment is "certified" by NSF or "accepted" by USEPA. Rather, it recognizes
that the performance of the equipment has been determined and verified by these organizations
under conditions specified in ETV protocols and test plans.
1.2 Purpose of Verification
The purpose of this verification was to evaluate treatment system performance under a simulated
intentional or non-intentional chemical contamination event. Because any contamination event
would likely be short-lived, the challenge period for each chemical lasted only one day. Long-
term performance over the life of the membrane was not investigated.
1.3 Development of Test/Quality Assurance (QA) Plan
USEPA's "Water Security Research and Technical Support Action Plan" (USEPA, 2004)
identifies the need to evaluate point-of-use (POU) and point-of-entry (POE) treatment system
capabilities for removing likely contaminants from drinking water. As part of the ETV program,
NSF developed a test/QA plan for evaluating POU reverse osmosis (RO) drinking water
treatment systems for removal of chemical contaminants. To assist in this endeavor, NSF
-------
assembled an expert technical panel, which gave suggestions on a protocol design prior to
development of the test/QA plan.
The product-specific test/QA plan for evaluating the ERO-R450E was entitled Test/QA Plan for
Verification Testing of the EcoWater Systems ERO-R450E Point-of-Use Drinking Water
Treatment System for Removal of Chemical Contamination Agents.
By participating in this ETV evaluation, the vendor obtains USEPA and NSF verified
independent test data indicating potential user protection against intentional or non-intentional
chemical contamination of drinking water. Verifications following an approved test/QA plan
serve to notify the public of the possible level of protection against chemical contamination
agents afforded to them by the use of a verified system.
1.4 Challenge Chemicals
The challenge chemicals for this verification are listed in Table 1-1.
Table 1-1. Challenge Chemicals
Organic Chemicals Inorganic chemicals
Aldicarb Cadmium Chloride
Benzene Cesium Chloride (nonradioactive isotope)
Carbofuran Mercuric Chloride
Chloroform Strontium Chloride (nonradioactive isotope)
Dicrotophos
Dichlorvos
Fenamiphos
Mevinphos
Oxamyl
Strychnine
1.5 Testing Participants and Responsibilities
The ETV testing of the ERO-R450E was a cooperative effort between the following participants:
NSF
EcoWater Systems Inc.
USEPA
The following is a brief description of each of the ETV participants and their roles and
responsibilities.
1.5.1 NSF International
NSF is a not-for-profit organization dedicated to public health and safety, and to 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. The USEPA partnered with NSF to verify the performance of drinking water
treatment systems through the USEPA's ETV Program.
NSF performed all verification testing activities at its Ann Arbor location. NSF prepared the
test/QA plan, performed all testing, managed, evaluated, interpreted, and reported on the data
generated by the testing, and reported on the performance of the technology.
Contact Information:
NSF International
789 N. Dixboro Road
Ann Arbor, MI 48105
Phone: 734-769-8010
Fax: 734-769-0109
Contact: Bruce Bartley, ETV Program Manager
Email: bartley@nsf.org
1.5.2 EcoWater Systems Inc.
The ERO-R450E is manufactured by EcoWater Systems Inc., a manufacturer of residential and
commercial water treatment products.
The manufacturer was responsible for supplying the RO systems in accordance with Section
3.1.1, and for providing logistical and technical support as needed.
Contact Information:
EcoWater Systems Inc.
1890 Woodland Drive
Woodbury, MN 55125
Phone: 1-800-808-9899
Contact Person: Ms. Ann Baumann
1.5.3 U.S. Environmental Protection Agency
The USEPA, 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 the USEPA, and recommended for public release.
-------
Chapter 2
Equipment Description
2.1 Principals of Operation
2.1.1 Activated Carbon
Activated carbon removes organic chemicals from water through the process of adsorption. The
chemicals are attracted to and attach to the surface of the carbon through electrostatic
interactions. The adsorbent properties of activated carbon are a function of the raw material used
and the activation process. Once the carbon is saturated with adsorbed molecules, it must be
replaced.
2.1.2 RO Membrane
Membrane technologies are among the most versatile water treatment processes because of their
ability to effectively remove a wide variety of contaminants. RO membranes operate by the
principal of cross-flow filtration. In this process, the influent water flows over and parallel to the
filter medium and exits the system as reject water. Under pressure, a portion of the water
diffuses through the membrane becoming "permeate". The membrane allows water molecules to
pass through its pores, but not most dissolved inorganic chemical molecules and larger molecular
weight organic chemical molecules. These molecules are concentrated in and washed away with
the reject water stream.
Unlike activated carbon, which reaches and exhaustion point and needs to be replaced, the
reduction capabilities of RO membranes remain in effect until the membrane is compromised.
Monitoring of membrane performance can be conducted by measuring the TDS of the permeate
water with a TDS monitor.
2.2 Equipment Capabilities
The ERO-R450E is certified by NSF to NSF/ANSI Standard 58 - Reverse Osmosis Drinking
Water Treatment Systems. The system has a certified production rate of 22.2 gallons per day.
This measurement is based on system operation at 50 pounds per square inch (psi) inlet pressure,
a water temperature of 77 °F, and a total dissolved solids (TDS) level of 750 + 40 mg/L. The
amount and quality of treated water produced varies depending on the inlet pressure, water
temperature, and level of TDS. These measurements were not subject to verification during this
study.
2.3 System Components
The ERO-R450E is a three-stage POU treatment system, employing an RO membrane, and
activated carbon filtration both upstream and downstream of the membrane. The system
includes a 3.1-gallon maximum capacity pressurized bladder tank for storing the treated water,
-------
and a faucet to mount on the kitchen sink. A photograph of the system is shown in Figure 2-1.
Please note that the information given in this section, and Section 2.4 is for informational
purposes only, and is not subject to verification.
Figure 2-1. Photograph of the ERO-R450E
2.4 System Operation
Incoming water first passes through a carbon filter designed to remove chlorine and particulate
matter, such as rust and silt. The second stage of treatment is the reverse osmosis membrane,
which reduces a wide variety of inorganic and larger molecular weight organic contaminants,
and also protozoan cysts such as Cryptosporidium and Giardia. The permeate water is sent to the
storage tank. When the user opens the faucet, the partially treated water leaves the storage tank,
passes through a second carbon filter to remove organic chemicals, mercury, and any taste and
odor chemicals, and then exits the faucet. Figure 2-2 shows a schematic diagram of the ERO-
R450E, with the path of water through the system illustrated.
-------
When the flow of water into the system is started, treated water will be continually produced
until the storage tank is nearly full. At that time, the water pressure in the tank causes an
automatic shut-off device to activate, stopping the flow of water through the system. After a
portion of the water is dispensed from the storage tank, the shut-off device deactivates, allowing
water to again flow into the system until the storage tank is nearly full. The operational storage
tank capacity will vary slightly from system to system, and may also be affected by the inlet
water pressure. The capacity was measured to be approximately 2.5 gallons when the system
was tested for NSF/ANSI Standard 58 certification.
BLUE
PRODUCT WATER
PRODUCT
WATER
FAl ICFT //
ir gap ^
vn"
//
t- /
//
J
* 4
t/
gravity
drain
t
X^
f
4
RED »
drain flow
control
f AUTOMATIC \
SHUTOFF y \
WATER GREEN
IN " ^
f
**
t
»
\1
check
valve
j
YELLOW -41 i*>
1
\ 0 *
Jfi
4
t
IS
o«.
4
t
4
t
^-J-^
PRODUCT
WATER
STORAGE
s^ ^X
RO
PREFILTER MEMBRANE POSTFILTER
Figure 2-2. Schematic Diagram of the ERO-R450E
The ERO-R450E has a volume meter and TDS level meters that measure the volume of treated
water produced, and the level of TDS in the influent and effluent water. The faucet has a three
colored indicator light to tell the user when to replace the carbon filters and RO membrane.
Under normal operation, the indicator light is green. After six months have passed, or 750
gallons of treated water have been produced, the light changes to amber, indicating that the
carbon filters need to be replaced. The light turns red when the RO membrane's TDS rejection
falls below 75%, as measured by comparing the influent and effluent TDS levels. When the red
light comes on, the RO membrane should be replaced. The user must reset the meters each time
any treatment elements are replaced.
2.5 Rate of Waste Production
The rate of reject water production was measured during the certification process for NSF/ANSI
Standard 58 certification. The efficiency rating, as defined by Standard 58 is the percentage
-------
measure of the amount of influent water delivered as permeate under a closed permeate
discharge set of actual use conditions. The efficiency rating of the ERO-R450E is 9.7%, which
means the system produces approximately nine gallons of reject water for each gallon of product
water produced. The efficiency rating was not verified as part of this evaluation.
2.6 Equipment Operation Limitations
EcoWater Systems gives the following operation limitations:
feed water temperature of 40-100°F;
feed water pressure of 40-100 psi;
feed water pH 4-10;
non-detectable iron, manganese, or hydrogen sulfide in the feed water supply;
maximum inlet water TDS level of 2,000 mg/L;
inlet water hardness of less than 10 grains per gallon (1 grain per gallon equals 17.1
mg/L, expressed as calcium carbonate equivalent); and
maximum inlet water chlorine level of 2 mg/L.
2.7 Operation and Maintenance Requirements
The following are the operation and maintenance requirements specified in the product owner's
manual:
Replacement of the carbon filters when indicated by the meter (every six months or 750
gallons);
Replacement of the RO membrane cartridge when indicated by the meter; and
Sanitization of the system when the carbon filters or RO membrane are replaced
(instructions included in the owner's manual.)
-------
Chapter 3
Methods and Procedures
3.1 Introduction
The challenge tests followed the procedures described in the Test/QA Plan for Verification
Testing of the EcoWater Systems ERO-R450E Point-of-Use Drinking Water Treatment System
for Removal of Chemical Contamination Agents.
As described in Section 2.3, the ERO-R450E employs an RO membrane and carbon filters to
treat drinking water. The system was first tested with only the RO membrane component in
place. After the RO membrane challenges were complete, the post-membrane carbon filter was
challenged alone. This approach allowed an evaluation of the individual performance of each
component, and also served to simulate a worst-case scenario where the carbon filters are at or
past the end of their useful life. This approach also allowed each treatment component to be
challenged using a test water that presented more of a worse-case scenario for that component.
The pre-membrane carbon filter was not tested, because it is only designed to remove chlorine
and particulate matter to protect the RO membrane.
3.1.1 RO Membrane Challenges
The RO membranes were challenged with each chemical in Table 3-1. The target challenge
concentration for each chemical was 1 mg/L, which is much higher than most challenge levels in
the NSF/ANSI Standards for POU devices. Of the chemicals in Table 3-1 included in the POU
device standards, the highest challenge is chloroform at 450 (ig/L for the total trihalomethanes
reduction test.
Only two membranes were challenged with each chemical. The organic chemical challenges and
mercury challenge were conducted individually, but cadmium, cesium, and strontium were
combined into one challenge. Each membrane was only tested with one of the ten organic
chemicals, because of concern that some of them, especially benzene and chloroform, could
damage the membranes or membrane seals at the high challenge levels. This approach
eliminated the possibility that membrane performance against subsequent chemicals was
negatively biased. TDS reduction was also measured during the challenges, to serve as a
membrane performance benchmark, and also to evaluate whether any organic chemicals
damaged the membrane or integrity of the membrane seals.
A total of twenty RO membranes were tested, divided into ten pairs. The inorganic chemical
challenges were conducted first. The systems tested for the inorganic chemical challenges were
used again for an organic chemical challenge. As discussed in Section 1.2, each challenge period
was only one day. The systems were operated for six tank-fill periods, and then were allowed to
rest overnight. Influent and effluent samples were collected during the operation period, and also
the next morning after the rest period. In addition to influent and effluent samples, reject water
samples were also collected and analyzed in an attempt to determine whether any of the
-------
chemicals adsorbed onto or absorbed into the membrane material in significant amounts. See
Section 3.2.5.2 for RO membrane challenge protocol details.
Table 3-1. Challenge Chemicals
Organic Chemicals Inorganic Chemicals
Aldicarb Cadmium Chloride
Benzene Cesium Chloride (nonradioactive isotope)
Carbofuran Mercuric Chloride
Chloroform Strontium Chloride (nonradioactive isotope)
Dicrotophos
Dichlorvos
Fenamiphos
Mevinphos
Oxamyl
Strychnine
3.1.2 Post-Membrane Carbon Filter Challenges
The post-membrane carbon filter was tested alone for reduction of some of the chemicals. The
carbon filter was challenged with the organic chemicals the RO membrane did not remove to a
level of 30 |j,g/L or less. The inorganic chemicals were considered on a case-by-case basis, since
USEPA does not consider carbon to be the best available technology for removing cadmium,
cesium, or strontium. As with the membranes, the carbon filters were challenged in pairs, and
each pair was only tested once. Each challenge was 15 hours. The target challenge
concentrations for the carbon filter tests were the maximum effluent levels measured during the
RO tests. See Section 3.2.5.3 for the post-membrane carbon filter test protocol details.
3.1.3 System Operation Scenarios
The challenge protocol was designed to evaluate system performance under two different
operation scenarios. The first is operation with the product water storage tank over half full,
giving high back-pressure. This is how the system is likely to operate in the home, as the user
will usually dispense small volumes of water until the shut-off valve deactivates, allowing the
storage tank to fill again. RO membrane performance is affected by the net driving pressure on
the membrane. The net driving pressure is the feed water pressure minus the osmotic pressure
minus the back-pressure from the storage tank. As the storage tank fills up and the tank bladder
expands, the back-pressure increases, reducing the net driving pressure. As the net driving
pressure drops, the ion rejection performance of the membrane can also drop (Slovak, 2000).
This test protocol was designed so that the membranes operate for multiple tank fills under
conditions where the net driving pressure was as low as possible. After the first tank fill, the lab
technician dispensed the product water to the drain until the shut-off valve deactivated, allowing
the RO membrane to again produce treated water. This cycle was repeated for a total of five
storage tank fill periods.
-------
The second operation scenario is continued contaminant rejection while the system is at rest.
The NSF/ANSI Standard 58 testing protocols call for a two-day stagnation period to check
whether the membrane can maintain rejection of the contaminants. NSF has observed that RO
systems can give higher contaminant concentrations after the rest period than before. This
phenomenon is due to the membrane's difficulty maintaining the osmotic differential across the
membrane, and perhaps also imperfections in the membrane material. At the end of each
challenge, the membranes were allowed to rest under pressure overnight, and product water
samples were collected for analysis the next morning.
3.2 Verification Test Procedure
3.2.1 Challenge Protocol Tasks
The following are the tasks in the challenge protocol, and the order in which they were
conducted:
1. Installation of the RO membrane devices on the test rig, and seven days of
conditioning (Section 3.2.4.1);
2. One-day TDS challenge test to evaluate system integrity (Section 3.2.5.1);
3. Conditioning of the post-membrane carbon filters while the RO membrane tests are
being conducted (Section 3.2.4.2); and
4. Chemical challenge tests
a. RO inorganic chemical challenges (Section 3.2.5.2)
b. RO organic chemical challenges (Section 3.2.5.2)
c. Post-membrane carbon filter challenges (Section 3.2.5.3).
3.2.2 Test Rig
All test units were plumbed to "injection rig" test stations in the NSF Drinking Water Treatment
Systems Testing Laboratory. The injection rigs have a common 90-gallon tank to hold the test
water without the challenge chemicals. Fresh water is periodically added to the tank as it is
being used. Online monitors and a computer system automatically control the water level and
water chemistry. Downstream of the feedwater tank, a precisely controlled pump is used to
inject the challenge chemical(s) at the proper concentrations. Immediately downstream of the
pump lies a motionless in-line mixer to assure complete mixing of the challenge water. An
influent sample port is downstream of the in-line mixer. No schematic diagram of the injection
rig is available, due to the proprietary nature of the design.
3.2.3 Test Water
3.2.3.1 RO Membrane Conditioning and Challenge Test Water
The test water for the RO membrane conditioning and challenges was a synthetic water
constructed from deionized municipal drinking water. The municipal water was first filtered
through activated carbon to remove chlorine, then deionized and treated with reverse osmosis.
Sodium chloride was added for TDS, and the pH was adjusted with hydrochloric acid (HC1) or
10
-------
sodium hydroxide (NaOH), if necessary, to achieve the following characteristics prior to addition
of the challenge chemical(s):
pH - 7.5 ± 0.5 for the IDS reduction test, conditioning, and organic chemical challenges,
6.0-6.5 for the inorganic chemicals challenge;
total chlorine - < 0.05 mg/L;
temperature - 25 ± 1 °C;
IDS - 750 ± 75 mg/L; and
turbidity - < 1 Nephelometric Turbidity Unit (NTU).
TDS, pH, temperature, and turbidity were maintained within the appropriate range by a computer
system with on-line monitors. In addition, grab samples were collected and analyzed for all
parameters according to the sampling plans described in Sections 3.2.4.1, 3.2.5.1, and 3.2.5.2.
Note that the pH specification for the inorganic chemicals challenges was 6.0 to 6.5, to ensure
that the metals were present as dissolved free ions in the challenge water. This ensured that the
inorganic chemicals challenges were testing the ability of the RO membrane to reject the ions
instead of physically removing suspended particles of the metals.
3.2.3.2 Post-Membrane Carbon Filter Conditioning and Test Water
The test water for post-membrane carbon filter conditioning and testing was the "general test
water" specified in NSF/ANSI Standard 53, Drinking water treatment units - health effects (NSF
International, 2002). This water is the Ann Arbor municipal drinking water that is adjusted, if
necessary, to have the following characteristics prior to addition of the challenge chemical:
pH-7.5 ±0.5;
TDS - 200-500 mg/L
temperature - 20 ± 2.5 °C;
total organic carbon (TOC) - > 1.0 mg/L; and
turbidity - < 1 NTU.
Please note that the TOC parameter only has a minimum level specified, since it is the natural
TOC in the municipal water supply. The natural TOC in the water supply ranged from 2.1 to 2.8
mg/L during testing. However, the TOC levels in the organic chemical challenge waters were
much higher due to the methanol used as the carrier solution for the chemicals.
TDS, pH, and temperature were maintained within the appropriate range by a computer system
with on-line monitors. The pH of the Ann Arbor drinking water was above 7.5 during the test
period, so the pH was adjusted with HC1. The TDS level was within the allowable range, so no
adjustments were needed. The water was not dechlorinated prior to use.
Grab samples were collected and analyzed for all parameters according to the sampling plans
described in Sections 3.2.4.2 and 3.2.5.3. Total chlorine was also measured, although there is no
specification given for it as there is in Section 3.2.3.1 for the RO membrane test water.
11
-------
3.2.3.3 Chemical Challenges
The appropriate chemical(s) were added to the base test waters given in Sections 3.2.3.1 and
3.2.3.2 to make the challenge waters. The RO membrane challenge target concentration for each
chemical was 1 + 0.5 mg/L. The target challenge concentrations for the carbon filter tests were
the maximum effluent levels measured during the RO tests. For each challenge, a concentrated
solution of the chemical(s) was made, and this mixture injected into the influent water stream at
an appropriate rate. Due to analytical procedure lengths, the amount of chemical to add to the
test water to achieve the proper challenge concentration was calculated based on the known
concentration in the feed solution. The tests were conducted without waiting for confirmation of
the influent level from the chemistry laboratory.
3.2.4 Test System Installation and Conditioning
3.2.4.1 RO Membrane Test Units
The RO membranes were installed on the test rigs by an NSF DWTS Laboratory technician
according to the instructions in the ERO-R450E owner's manual. The recommended
conditioning procedure of operation for six tank-fill periods was not conducted, instead the
membranes underwent a seven day, seven tank-fills conditioning period. Previous POU RO
system ETV tests for microbial agents indicated that perhaps membrane performance does not
stabilize until after four or five days (four or five tank-fills) of conditioning. A seven-day
conditioning period ensured that the membranes were performing optimally prior to the chemical
challenges.
For the first six days, the membranes were operated at 60 + 3 psi inlet pressure for one storage
tank fill period per day using the water described in Section 3.2.3.1. Influent water samples were
collected each day at the beginning of the operation period for analysis of pH, TDS, temperature,
total chlorine, and turbidity. The membranes rested under pressure overnight, and the storage
tanks were emptied the next morning prior to beginning that day's operation period.
On the seventh day, the membranes were instead operated at 80 + 3 psi inlet pressure. Influent
water samples were collected at the beginning of the operation period for analysis of pH, TDS,
temperature, total chlorine, and turbidity. The times required to fill the storage tanks were
measured and recorded for the three test units whose tanks filled the fastest. On the morning of
the eighth day, the times to dispense the first liter of water and to empty the storage tanks with
the faucet fully open were measured and recorded for the three test units whose operation times
were recorded the previous day. The tank fill times, times to empty the storage tank, and first
liter flow rates were used to determine the operating parameters for the post-membrane carbon
filters during the carbon filter challenge tests. The longest time to empty the storage tank was
used for the "on" time portion of the operating cycle. The shortest tank fill time was used for the
"off portion of the cycle. The flow rates during the carbon filter challenges were set at the
fastest first liter flow rate. Operation at 80 psi instead of 60 psi caused the tank fill time to be
shorter, which gave a worse case testing scenario for the carbon filters. See Section 3.2.5.3 for
further discussion about the post-membrane carbon filter challenge tests.
12
-------
3.2.4.2 Post-Membrane Carbon Filter Test Units
The carbon filters were plumbed to a test station and operated using the water described in
Section 3.2.3.2 amended with 300 + 90 |o,g/L of chloroform until 375 gallons passed through
each filter. This is the volume equal to one-half of EcoWater System's stated capacity of 750
gallons for the filter. The filters were operated at an inlet water pressure of 60 + 3 psi and a
maximum flow rate of 0.5 gallons per minute (gpm), on a ten minutes on, ten minutes off cycle.
Chloroform at 300 |o,g/L is the influent challenge concentration for the VOC (volatile organic
chemical) reduction test in NSF/ANSI Standard 53 (chloroform is the surrogate test chemical).
The chloroform served to load the carbon filters to a degree that simulated contaminant loading
in the middle of their effective lifespan. Influent samples were collected for analysis of
chloroform, pH, temperature, TOC, and turbidity at start-up, approximately 25% of capacity, and
approximately 50% of capacity. Effluent samples were collected at the same three points for
chloroform analysis.
If the filters were not immediately used for a challenge test, they were stored with the
conditioning water still in them. The manifold inlets and outlets were closed off by valves to
ensure that the chloroform remained on the carbon.
3.2.5 Challenge Protocols and Sampling Plans
3.2.5.1 TDS Reduction System Performance Check
After the RO membrane conditioning period was complete, they underwent a short-term TDS
reduction test to verify that they were operating properly. The challenge was conducted as
follows:
1. The product water storage tanks were drained, and membrane operation was started at 50 ± 3
psi inlet pressure using the water described in Section 3.2.3.1 without any challenge
chemicals added.
2. Immediately after the membranes began operation, influent samples were collected for
analysis of pH, temperature, total chlorine, turbidity, and TDS.
3. The systems were allowed to operate until the automatic shut-off mechanisms activated.
4. The entire contents of the storage tanks were emptied into separate containers, and three 250
mL samples were collected from each container for TDS analysis.
Removal of 75% or more of the TDS was required for the use of each membrane for the
chemical challenges.
3.2.5.2 RO Membrane Challenge Testing
As discussed in Section 3.1.1, the RO membrane test units were divided into ten pairs. The
inorganic chemical challenges were conducted first, followed by the organic chemicals. Figure
3-1 shows a pair of test devices plumbed to the test rig.
The challenge tests were conducted as follows:
1. At the start of each challenge period, the test system storage tanks were emptied.
13
-------
Figure 3-1. RO Membrane Systems Installed at Test Station
2. The initial dynamic inlet water pressure was set at 50 + 3 psi, and test system operation was
started using the test water described in Section 3.2.3.1 with the proper challenge chemical(s)
added.
3. Influent and effluent water samples were collected for analysis of the challenge chemical(s)
and TDS immediately after the units began operation. Influent samples were also collected
for analysis of pH, temperature, total chlorine, and turbidity. The effluent samples were
collected from the faucet that comes with the system. All influent and effluent samples for
challenge chemical analysis were collected and analyzed in triplicate, except where
indicated. To collect the triplicate samples, the volumes necessary to obtain the triplicate
samples were first collected into a polyethylene container, and then the triplicate samples
were collected from that volume. Due to the volatility of benzene and chloroform, true
triplicate samples were not collected for these chemicals. Instead, three consecutive replicate
samples were collected directly into the sample bottles that were delivered to the NSF
Chemistry Laboratory. TDS samples were collected as single samples.
14
-------
4. While under operation for the first storage tank fill period, duplicate samples were collected
from the reject water line of one of the systems for challenge chemical(s) analysis. Samples
were collected at start-up, approximately halfway through, and approximately three-fourths
of the way through the period.
5. The units were operated continuously until the shut-off valves activated. The faucets were
then fully opened, and a minimum of one liter, the volume required for sample analysis, or
the amount needed to fully deactivate the shut-off valve, was dispensed to drain from each
system. Full deactivation was estimated by monitoring resumption of the flow of reject water
as the product water is dispensed. The shut-off valve was considered fully deactivated when
the flow of reject water appeared to have fully resumed.
6. Step 5 was repeated until five storage tank fill periods were complete. After the third storage
tank fill period ended, influent and effluent samples were collected for analysis of the
challenge chemical(s) and TDS.
7. Approximately halfway through the last tank fill period, duplicate reject water samples were
collected for challenge chemical(s) analysis. The samples were collected from the same
system from which the reject water samples were collected in step 4. This sample served to
check whether any chemical adsorption/absorption observed during the first storage tank fill
period was still occurring, or the membrane became saturated with the chemical.
8. After the fifth storage tank fill, effluent samples were collected from each system for
challenge chemical(s) and TDS analysis. Influent samples were collected for analysis of the
challenge chemical(s), TDS, pH, temperature, total chlorine, and turbidity. If a system did
not resume operation after sample collection, the additional volume necessary to resume
operation was dispensed from each system.
9. The units were then allowed to operate until the shut-off valves activated, and then rest under
pressure for at least eight hours. After the rest period, the faucets were fully opened, and the
first draw out of each faucet was collected for single challenge chemical and TDS analysis.
After collection of the first draw water, the rest of the contents of each storage tank were
collected into suitable containers, and three samples were collected from each volume for
triplicate challenge chemical analysis. Table 3-2 gives a summary of the sampling plan.
3.2.5.3 Post-Membrane Carbon Filter Challenge Testing
The post-membrane carbon filter in the ERO-R450E is downstream from the storage tank, so it
was tested at the flow rate measured at the faucet outlet during the RO membrane conditioning
step. Each challenge was 15 hours. The filters were operated on an "on/off operation cycle
where the "on" portion was the time required to empty the storage tank when full, and the "off
portion of the cycle was the time required to fill the storage tank at 80 psi inlet pressure, as
measured during the RO membrane conditioning period. Figure 3-2 shows a pair of carbon
filters being tested for dichlorvos removal.
The challenge tests were conducted as follows:
1. The proper "on/off cycle parameters were entered into the test station computer.
15
-------
Table 3-2. Summary of Sampling Plan for RO Membrane Challenges
Influent Sample Numbers
Sample Point
Water Chemistry
Parameters
Challenge
Chemical
TDS
Effluent Sample Numbers
(per system)
Challenge
Chemical TDS
Start Up
1 sample for
each parameter
1
1st Tank Reject Water Samples
Startup
Half Tank
Three-fourths Tank
2 (from one system)
2 (from one system)
2 (from one system)
3rd Tank Fill
5th Tank Fill
Reject Water - Halfway Through
5th Tank Fill
Post-Rest - First Draw
Post-Rest - Rest of Tank
3
1 sample for 3
each parameter
1 3
1 3
2 (from one system)
1
o
J
1
1
1
Figure 3-2. Post-Membrane Carbon Filters Installed at Test Station
16
-------
2. The initial dynamic inlet water pressure was set at 60 + 3 psi, and filter operation was started
using the water described in Section 3.2.3.2 with the proper challenge chemical added. The
flow rate was adjusted as necessary using a valve downstream of each filter on the effluent
line.
3. Influent and effluent samples were collected for challenge chemical analysis immediately
after operation began. All effluent samples were collected during the last half of the "on"
portion of the operation cycle, so that the dwell water was flushed out prior to sample
collection. All challenge chemical samples were collected and analyzed in triplicate. The
sample volumes were those required to obtain the triplicate samples.
4. Single influent samples were also collected for analysis of pH, TDS, temperature, TOC, total
chlorine, and turbidity whenever challenge chemical samples were collected.
5. After 7.5 and 15 hours of operation, second and third sets of influent and effluent samples
were collected for challenge chemical analysis. The flow of challenge water through the
filters was started manually if they were not in the "on" portion of the operation cycle. Table
3-3 gives a summary of the sampling schedule.
Table 3-3. Summary of Sampling Plan for Post-Membrane Carbon Filter Challenges
Influent Water Challenge Chemical Challenge Chemical
Chemistry Sample Influent Effluent Sample
Sample Point Numbers SampleNumbers Numbers
Startup
7.5 Hours
15 Hours
1 for each parameter
1 for each parameter
1 for each parameter
3
3
3
3
3
3
3.3 Analytical Methods
3.3.1 Water Quality Analytical Methods
The following are the analytical methods used during verification testing. All analyses followed
procedures detailed in NSF's Standard Operating Procedures (SOPs). The reporting limits, and
the acceptable precision and accuracy for each parameter are shown in Table 3-4.
pH - All pH measurements were made with an Orion Model SA 720 meter. The meter
was operated according to the manufacturer's instructions, which are based on Standard
Method 4500-H+.
Temperature - Water temperature was measured using an Omega model HH11 digital
thermometer.
TDS (by conductivity) - TDS for the TDS reduction system check test was measured
through conductivity according to Standard Method 2510 using a Fisher Scientific
Traceable Conductivity Meter. This method has been validated for use with the test
water; NSF uses this method for analysis of samples from TDS reduction tests under
Standard 58.
TDS (gravimetrically) - The TDS in the carbon filter conditioning and challenge water
was measured gravimetrically. The method used was an adaptation of USEPA Methods
17
-------
160.3 and 160.4. An appropriate amount of sample was placed in a pre-weighed
evaporating dish. The sample was evaporated and dried at 103-105 °C to a constant
weight. The dish was then weighed again to determine the total solids weight.
Total Chlorine - Total chlorine was measured according to Standard Method 4500-C1 G
with a Hach Model DR/2010 spectrophotometer using AccuVac vials.
Table 3-4. QC Limits
Parameter Reporting Limit
pH NA
TDS (conductivity) 2 mg/L
TDS (gravimetric) 5 mg/L
TOC 0.1 mg/L
Total Chlorine 0.05 mg/L
Turbidity 0.1 NTU
Aldicarb 1.0 (o,g/L
Benzene 0.5 (o,g/L
Cadmium 0.3 (o,g/L
Carbofuran 1 (o,g/L
Cesium 1 (o,g/L
Chloroform 0.5 (o,g/L
Dicrotophos 10 (o,g/L
Dichlorvos 0.2 (o,g/L
Fenamiphos 4 (o,g/L
Mercury 0.2 (o,g/L
Mevinphos 0.2 (o,g/L
Oxamyl 1.0 (o,g/L
Strontium 2 (o,g/L
Strychnine 5 ^ig/L
LFB = Laboratory Fortified Blank
LFM = Laboratory Fortified Matrix
RPD = Relative Percent Deviation
RSD = Relative Standard Deviation
and Method Reporting
Acceptable Precision
(RPD or RSD)
RPD < 10%
RPD < 10%
RPD < 10%
RPD < 10%
RPD < 10%
RPD < 10%
RSD < 20%
RSD < 20%
RSD < 20%
RSD < 20%
RSD < 20%
RSD < 20%
RSD < 30%
RSD < 30%
RSD < 30%
RSD < 20%
RSD < 30%
RSD < 20%
RSD < 20%
RSD < 20%
Limits for Analyses
Acceptable Accuracy (% recovery)
90-110%
80-120%
90-110%
80-120%
90-110%
95-105%
LFB LFM
80-120% 65-135%
80-120% NA
85-115% 70-130%
80-120% 65-135%
85-115% 70-130%
80-120% NA
70-130% 70-130%
70-130% 70-130%
70-130% 70-130%
85-115% 70-130%
70-130% 70-130%
80-120% 65-135%
85-115% 70-130%
70-130%
3.3.2 Challenge Chemical Analytical Methods
The following are the analytical methods used during verification testing. All analyses followed
procedures detailed in NSF SOPs. The reporting limits, and the acceptable precision and
accuracy for each parameter are shown in Table 3-4.
Aldicarb, Carbofuran, and Oxamyl were measured by high pressure liquid
chromatography (HPLC) according to USEPA Method 531.1 or 531.2.
Dichlorvos, Dicrotophos, Fenamiphos, and Mevinphos were measured by gas
chromatography/mass spectrometry (GC/MS) according to USEPA Method 525.2.
Cadmium, Chromium, Mercury, and Strontium were measured by Inductively Coupled
Plasma - Mass Spectrometry (ICP-MS) according to USEPA Method 200.8.
18
-------
Benzene and Chloroform were measured by purge and trap capillary gas chromatography
according to USEPA Method 502.2.
There is no standard analytical method for strychnine. NSF developed a method to
measure it using reverse phase HPLC with ultraviolet lamp detection.
19
-------
Chapter 4
Results and Discussion
4.1 RO membrane Conditioning
As discussed in Section 3.2.4.1, the RO membranes were conditioned for seven days prior to the
chemical challenges. All of the influent water quality parameters in Section 3.2.3.1 were
maintained within the allowable ranges. The individual data values for these parameters can be
found in Table A-l of Appendix A
4.1.1 RO Membrane System Operation Data
As described in Section 3.2.4.1, the storage tank fill times, first liter dispense times, and times to
dispense the entire tanks were measured and recorded for the three systems whose tanks filled
the fastest. The first liter flow rates were calculated for each system from the first liter dispense
times. The results are given below in Table 4-1. This data was used to determine the operation
parameters for the carbon filter challenges.
Table 4-1. RO Membrane
Unit Tank Fill Time 1st Liter Time
Number (minutes) (seconds)
4
7
9
73
72
71
14.4
13.8
16.1
System Operation Data
1st Liter Flow
Rate (gpm) Tank Dispense Time
1.10
1.15
0.98
4 min.,
4 min.,
5 min.,
51 sec.
26 sec.
1 1 sec.
4.2 Post-Membrane Carbon Filter Conditioning
As described in Section 3.2.4.2, the post-membrane carbon filters were conditioned with water
containing 300 + 90 ug/L of chloroform until 375 gallons had passed through them. Eight filters
were conditioned first, and then another seven were conditioned later. Influent and effluent
samples were collected for analysis at start-up, approximately 188 gallons, and approximately
375 gallons. The influent and effluent chloroform data are given below in Table 4-2. All water
chemistry parameters measured during carbon filter conditioning were within the limits specified
in Section 3.2.3.2. The water chemistry data are presented in Table A-2 of Appendix A.
There appeared to be a quality problem with the post-membrane carbon filters submitted for the
tests. The ERO-R450E is certified under NSF/ANSI Standard 58 for the VOC reduction claim,
which uses chloroform as a surrogate challenge chemical, and is solely based on the performance
of the post-membrane carbon filter. To obtain the VOC reduction claim, the filter must reduce a
300 + 30 |o,g/L challenge down to less than 15 |o,g/L at each sample point up to 120% of the 750
gallon design capacity. Here, six of the fifteen carbon filters had effluents exceeding 15 |j,g/L at
or prior to 50% of capacity. The influent and effluent chloroform data was not available to the
lab technicians when they were picking which carbon filters to test for the chemical challenges,
20
-------
so four of the six filters with poor chloroform reduction performance were used. However, these
four filters were able to reduce the chemical challenges by 90% or more. See Section 4.5 for the
post-membrane carbon filter challenge data.
Table 4-2. Post-Membrane Carbon Filter Conditioning Chloroform Data
Chloroform (ng/L)
25% of 50% of
Sample Start-Up Capacity Capacity
Group 1 Influent
Unit 1 Effluent
Unit 2 Effluent
Unit 3 Effluent
Unit 4 Effluent
Unit 5 Effluent
Unit 6 Effluent
Unit 7 Effluent
Unit 8 Effluent
Group 2 Influent
Unit 9 Effluent
Unit 10 Effluent
Unit 11 Effluent
Unit 12 Effluent
Unit 13 Effluent
Unit 14 Effluent
Unit 15 Effluent
340
ND (0.5)
ND (0.5)
ND (0.5)
ND (0.5)
ND (0.5)
13
ND (0.5)
ND (0.5)
310
2.6
12
ND (0.5)
9.0
ND (0.5)
9.0
34
310
ND (0.5)
ND (0.5)
ND (0.5)
ND (0.5)
ND (0.5)
22
ND (0.5)
ND (0.5)
270
9.1
23
30
21
ND (0.5)
21
68
310
ND (0.5)
ND (0.5)
ND (0.5)
ND (0.5)
ND (0.5)
24
ND (0.5)
ND (0.5)
360
36
29
ND (0.5)
30
ND (0.5)
36
73
4.3 TDS Reduction System Performance Check
After the RO membranes were conditioned, all underwent the TDS reduction test described in
Section 3.2.5.1. The maximum effluent TDS level measured was 100 mg/L, corresponding to a
minimum 87% reduction of TDS. The average TDS reduction was 91%. EcoWater Systems'
reported TDS reduction for the ERO-R450E is a minimum of 87%, and an average of 92.6%, so
test systems were representative of expected membrane performance. The TDS reduction data
for each RO membrane system can be found in Table A-3 of Appendix A.
4.4 RO Membrane Chemical Challenges
The RO membrane challenges were conducted according to the procedure in Section 3.2.5.2.
The tank-fill times were approximately 70 minutes, so the systems were in operation for
approximately seven hours per challenge.
4.4.1 Inorganic Chemicals Challenges
The inorganic chemicals challenge data are shown in Table 4-3. Each challenge chemical data
point is the arithmetic mean of the triplicate sample analyses, except for the post-rest first liter
draws, which were only single samples. All individual sample values constituting the triplicate
21
-------
analyses are presented in Table A-4 of Appendix A. The challenge water chemistry data are
presented in Table A-6 of Appendix A.
Unit l(unit 11) removed 99% of both cadmium and strontium, while unit 2 (unit 12) removed
95% of both metals. Cesium was removed by 80% and 84%. The RO membrane did not remove
a significant portion of the mercury challenge, but this not a surprising result. There are no POU
RO systems certified by NSF for mercury reduction because mercury is not well removed by RO
membranes using the test water specified in NSF/ANSI Standard 58.
Table 4-3. RO Membrane Inorganic Chemicals Reduction Data
Cd, Cs, Sr Mercury
Cadmium Cesium Mercury Strontium Challenge Challenge
Sample (ng/L) (ng/L) (nfi/L) (nfi/L) IDS (mg/L) TDS (mg/L)
Start-up Influent
Start-up Effluent, Unit 1
Start-up Effluent, Unit 2
3rd Tank Influent
3rd Tank Effluent, Unit 1
3rd Tank Effluent, Unit 2
_4 ____ j-g^-
5th Tank Effluent, Unit 1
5th Tank Effluent, Unit 2
Post-Rest 1st Liter Draw, Unit 1
Post-Rest 1st Liter Draw, Unit 2
Post-Rest 2nd Sample, Unit 1
Post-Rest 2nd Sample, Unit 2
Mean Influent
Mean Effluent, Unit 1
Mean Effluent, Unit 2
Percent Reduction, Unit 1
Percent Reduction, Unit 2
Overall Percent Reduction
Units Tested (Unit #'s)
950
9.9
48
960
23
43
960
10
55
10
61
11
56
960
13
53
99
95
97
11,12
920
110
140
930
160
190
920
150
210
170
200
160
210
930
150
190
84
80
82
11,12
1000
980(1)
860
1100
1100
970
1200
1100
1100
1000
930
990
990
1100
1000
970
9
12
9
11, 12
950
9
50
960
27
44
960
10
57
10
55
10
57
960
13
53
99
95
97
11, 12
730
60
85
750
91
130
740
92
120
98
120
740
81
110
89
85
750
64
70
750
84
94
750
93
100
94
100
750
80
88
89
88
(1) Number only the average of two of the triplicate analysis numbers, analytical error with the third.
The reject water sample data are given in Table 4-4. The values presented are the arithmetic
means of the duplicate sample analyses, except where indicated. The individual sample results
are presented in Table A-7 of Appendix A. The reject water levels are as expected, given that
the ERO-R450E has an efficiency rating of 9.7% (see Section 2.5 for further discussion). This
efficiency means the reject water should have approximately 10% more of the challenge
chemical than the influent water, assuming almost 100% rejection by the membrane.
22
-------
Table 4-4. Inorganic Chemicals Challenge Reject Water Data
Sample Cadmium (M-g/L) Cesium (M-g/L) Mercury (M-g/L) Strontium (M-g/L)
Start-up
1/2 through 1st Tank
3/4 through 1st tank
1/2 through 5th Tank
Unit Sampled
1200
1200
1100
1100
11
1100
1100
1000
1000
11
880
1200
1000
1200
11
1200
1200
1100
1100
11
4.4.2 Organic Chemical Challenges
The organic chemical challenge data are shown below in Table 4-5. Each data point is the
arithmetic mean of the triplicate sample analyses, except where indicated, and for the post-rest
first draw samples, which were only single samples. All individual sample values constituting
the triplicate analyses are presented in Table A-5 in Appendix A. The water chemistry data for
these challenges are presented in Table A-6 in Appendix A.
Table 4-5. RO Membrane Organic Chemical Challenge Data
Sample
Aldicarb Benzene Carbofuran Chloroform Dichlorvos
(Mg/L) (Mg/L) (ng/L)
Dicrotophos Fenamiphos Mevinphos Oxamyl Strychnine
Start-up Influent
Start-up Effluent, Unit 1
Start-up Effluent, Unit 2
3rd Tank Influent
3rd Tank Effluent, Unit 1
3rd Tank Effluent, Unit 2
5th Tank Influent
5th Tank Effluent, Unit 1
5th Tank Effluent, Unit 2
Post-Rest 1st Draw, Unit 1
Post-Rest 1st Draw, Unit 2
Post-Rest 2nd Sample, Unit 1
Post-Rest 2nd Sample, Unit 2
Mean Influent
Mean Effluent, Unit 1
Mean Effluent, Unit 2
Percent Reduction, Unit 1
Percent Reduction, Unit 2
Overall Percent Reduction
1100
11
21
980
25
14
1000
16
27
16
27
16(1)
26
1000
17
24
98
98
98
980
ND(0.5)
ND(0.5)
1100
7.7
3.1
930
15
7.0
9."7
7.1
13
7.0
980
9
5
>99
>99
>99
1100
17
15
1106
20
18
iioo
20
18
21
19
20
19
1100
20
18
98
98
98
1100
2.5
2.4
1100
45
59
1100
65
87
74
100
80
100
1100
53
70
95
94
94
1400
34
34
1300
65
72
1300
81
86
#
87
74
87
1300
66
73
95
94
95
1100
30
50
iTbo
40
70
TOGO
50
80
50
80
50
80
1100
40
70
96
94
95
910
ND(4)
ND(4)
950
ND(4)
ND(4)
930
ND(4)
ND(4)
5
5
5
4
930
4
4
>99
>99
>99
1200
31
41
1200
42
53
1200
45
53
46
54
43
56
1200
41
51
97
96
96
950
10
6
1000
11
8
970
11
9
11
9
11
9
980
11
8
99
>99
99
1100
ND(5)
7
1100
8
11
1100
13
8
8
13
10
14
1100
9
11
>99
99
>99
Units Tested (Unit #'s) 11,12 21,22 13,14 9,10 1,2 3,4 7,8 15,16 5,6 19,20
Note: The detection limit values were used for calculating the mean effluents and percent reductions.
(1) Number only the average of two of the triplicate analyses, analytical error with the third.
# Data point not reported due to analytical error.
As discussed in Section 3.1.1, the challenge water also contained TDS to serve as a membrane
integrity check. The TDS reduction data are presented in Table 4-6.
The reject water data are shown in Table 4-7. The values presented are the arithmetic means of
the duplicate sample analyses. The individual sample results are presented in Table A-8 of
Appendix A.
23
-------
Table 4-6. TDS Reduction Data for Organic Chemical Challenges
Sample
Aldicarb Benzene Carbofuran Chloroform Dichlorvos Dicrotophos Fenamiphos
TDS TDS TDS TDS TDS TDS TDS
(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)
Mevinphos Oxamyl Strychnine
TDS TDS TDS
(mg/L) (mg/L) (mg/L)
Start-up Influent
Start-up Effluent, Unit 1
Start-up Effluent, Unit 2
IFT^In^
3rd Tank Effluent, Unit 1
3rd Tank Effluent, Unit 2
5ffi Tank Influent
5th Tank Effluent, Unit 1
5th Tank Effluent, Unit 2
Post-Rest 1st Draw, Unit 1
Post-Rest 1st Draw, Unit 2
Mean Influent
Mean Effluent, Unit 1
Mean Effluent, Unit 2
Percent Reduction, Unit 1
Percent Reduction, Unit 2
740
36
43
740
59
50
740
55
65
55
65
740
51
56
93
92
760
42
42
750
65
62
750
68
67
67
68
750
61
60
92
92
750
38
36
730
55
55
730
59
57
61
59
730
53
52
93
93
760
41
44
730
59
67
750
63
68
65
72
750
57
63
92
92
730
39
43
730
60
59
730
68
67
74
87
730
60
64
92
91
720
46
69
730
68
91
730
78
100
84
110
730
69
93
91
87
760
35
39
760
52
63
760
58
69
66
72
760
53
61
93
92
760
41
47
760
57
63
760
61
68
67
73
760
57
63
93
92
760
42
40
760
60
59
760
66
60
68
60
760
59
55
92
93
750
37
36
752
59
52
750
62
58
64
59
750
56
51
93
93
Table 4-7. Organic Chemical Challenge Reject Water Data
Aldicarb Benzene Carbofuran Chloroform Dichlorvos Dicrotophos Fenamiphos Mevinphos Oxamyl Strychnine
Sample (pg/L) (|xg/L) (pg/L) (ng/L) (ng/L) (ng/L) (pg/L) (pg/L) (ng/L) (pg/L)
Start-up
1/2 through 1st
3/4 through 1st
1/2 through 5th
Unit Sampled
Tank
tank
Tank
1200
1200
1100
1100
11
890
910
980
1200
21
1500
1400
1400
1300
13
900
950
990
1200
9
1600
1500
1500
1500
1
1400
1300
1400
1200
3
1300
1100
1200
950
7
1600
1400
1500
1400
15
1100
1200
1300
1100
5
1400
1400
1400
1200
11
The RO membrane removed all chemicals by 94% or more. The effluent levels of many
chemicals increased from the start-up to the 3rd tank samples. This trend is also evident in the
TDS reduction data for all chemicals. The effluent levels of most chemicals then leveled off and
did not increase significantly through the end of the challenges. Benzene, chloroform,
dicrotophos, and dichlorvos did continue to increase from the 3rd tank to 5th tank samples, and
chloroform also increased in concentration from the 5th tank sample to the post-rest samples.
The effluent TDS levels associated with the dichlorvos, dicrotophos, fenamiphos, and mevinphos
challenges also increased from each sample point to the next through the entire challenge
periods. Note however, that the effluent TDS levels did not increase to above those measured
during the TDS system check tests. Thus, the rising TDS levels likely do not indicate that the
membranes were becoming significantly compromised due to exposure to the chemicals. More
research would be needed to evaluate whether the membranes were actually adversely affected
by chemical exposure.
The increases may be an artifact of the challenge protocol. The challenges began with empty
storage tanks, so there was no back-pressure on the membranes when the water collected for the
start-up samples passed through the membranes. The rest of the samples were collected when
the storage tanks were full, so the membranes had been operating with back-pressure. RO
membranes perform better without back pressure, so the 3rd tank, 5th tank, and post-rest samples
are likely more indicative of the true performance of the system as used by the consumer.
24
-------
The rise in effluent chloroform levels could also be due to the substance adsorbing onto and
diffusing through the membrane. The small size of the chloroform molecule may have also
played a role in its passage, since RO membranes remove organic chemicals by size exclusion.
The adsorption theory is lent some weight by an examination of the reject water data in Table 4-
7. The average concentration of chloroform is lower than for the other chemicals, as is that of
benzene. The reject water concentrations for all other chemicals are above the influent challenge
levels, indicating that they did not adsorb onto the membrane or internal surfaces in contact with
the water.
4.5 Post-Membrane Carbon Filter Challenges
Based on the RO membrane challenge results, and the criteria discussed in Section 3.1.2, the
post-membrane carbon filter was challenged with cesium, mercury, chloroform, dichlorvos,
dicrotophos, and mevinphos. The target challenge levels were the maximum effluent levels
measured during the RO membrane challenges. Based on the data in Table 4-2, the carbon filters
were operated at 1.15 gpm on an operation cycle where the "on" portion was five minutes and
eleven seconds, and the "off portion was one hour and ten minutes.
The carbon challenge results are shown below in Table 4-8. Each data point is the arithmetic
mean of the triplicate sample analyses. All individual sample values constituting the triplicate
analyses are presented in Table A-9 in Appendix A. The water chemistry data for these
challenges can be found in Table A-10 of Appendix A.
Table 4-8. Post-Membrane
Cesium Mercury
Sample (|ag/L) (|ag/L)
Target Influent Level 220
Start-up Influent 230
Start-up Effluent, Unit 1 210
Start:up Effluent, Unit 2 200
7.5 Hours influent 230
7.5 Hours Effluent, Unit 1 220
ZrlHours^Efflu^ntUnin 230
15 Hours influent 230
15 Hours Effluent, Unit 1 230
15 Hours .Effluent, .Unit. 2 230
Mean Influent 230
Mean Effluent, Unit 1 220
Mean Effluent, Unit 2 220
Percent Reduction, Unit 1 4.3
Percent Reduction, Unit 2 4.3
Overall Percent Reduction 4.3
Units Tested (Unit #'s) 1, 2
1000
910
43
21
710
47
26
650
46
760
45
24
94
97
95
9, 10
Carbon Filter Challenge Data
Chloroform Dichlorvos Dicrotophos
(HB/L) (ng/L) (nfi/L)
100
99
ND (0.5)
100
ND (0.5)
100
1.6
100
0.9
0.5
>99
>99
>99
7,8
95
100
ND (0.2)
8.5
ioo
0.3
7.3
ioo
0.2
7.2
100
0.2
7.9
>99
92
96
11, 12
90
80
ND(10)
ND (10)
90
ND(10)
ND (10)
90
ND(10)
ND(10)
90
ND (10)
ND (10)
89(D
89(D
89(D
3,4
Mevinphos
(H8/L)
61
24
ND (0.2)
2.7
49
ND (0.2)
4.3
46
0.3
5.1
40
0.2
3.9
>99
90
95
13, 14
Note: The detection limit values were used for calculating the mean effluents and percent reductions.
(1) Percent reductions limited by the chemical detection limit.
25
-------
The post-membrane carbon filter performed well against mercury and the organic chemicals, as
expected, but not against cesium. As discussed in Section 4.2, units 12 and 14 both
demonstrated chloroform breakthrough during conditioning. For the carbon filter challenges,
both units were paired with units that did not show breakthrough, and both gave higher effluent
levels of the challenge chemicals than did the other unit of the pair. However, units 12 and 14
still removed 92% and 90%, respectively, of the challenge chemicals.
Units 9 and 10, used for the mercury challenge, also both demonstrated chloroform breakthrough
during conditioning. These units gave average effluent mercury concentrations (45 and 24 |o,g/L)
in the same range as the maximum effluent chloroform concentrations during conditioning (36
and 29 ng/L). However, the mercury percent reductions are much higher, at 94% and 97%,
because the mercury challenge concentration was much higher.
4.6 Conclusions
Table 4-9 gives an estimate of the combined performance of both the RO membrane and post-
membrane carbon filter, using the data from Tables 4-3, 4-5, and 4-8. An examination of the
data in Table 4-9, along with the data in Tables 4-3 and 4-5, shows that the full ERO-R450E
system with the RO membrane and post-membrane carbon filter working in concert removed all
of the challenge chemicals but cesium by 96% or more.
Table 4-9. Combined Performance of RO Membrane and Post-Membrane Carbon Filter
Cesium Mercury Chloroform Dichlorvos Dicrotophos Mevinphos
Sample (nfi/L) fcg/L) (ng/L) (nfi/L) (nfi/L)
Mean Influent
Mean Effluent, Unit 1
Mean Effluent, Unit 2
Percent Reduction, Unit 1
Percent Reduction, Unit 2
Overall Percent Reduction
930
150
190
84
80
82
1100
45
24
96
98
97
1100
0.9
0.5
>99
>99
>99
1300
0.2
7.9
>99
>99
>99
1100
ND (10)
ND (10)
>99
>99
>99
1200
0.2
3.9
>99
>99
>99
26
-------
Chapter 5
QA/QC
5.1 Introduction
An important aspect of verification testing is the QA/QC procedures and requirements. Careful
adherence to the procedures ensured that the data presented in this report was of sound quality,
defensible, and representative of the equipment performance. The primary areas of evaluation
were representativeness, precision, accuracy, and completeness.
Because the ETV was conducted at the NSF testing lab, all laboratory activities were conducted
in accordance with the provisions of the NSF International Laboratories Quality Assurance
Manual.
5.2 Test Procedure QA/QC
NSF testing laboratory staff conducted the tests by following an NSF SOP created specifically
for the tests. NSF QA Department Staff performed an informal audit during testing to ensure the
proper procedures were followed.
All water chemistry measurements were within the specifications in Sections 3.2.3.1 and 3.2.3.2.
All chemical challenge levels for the RO membranes were within the allowable range of 1.0 +
0.5 mg/L. There were no allowable challenge level ranges specified for the carbon filter
challenges, but the measured challenge levels for the mercury and mevinphos challenges were
significantly low. The initial mercury challenge level was 910 ng/L, fairly close to the target
challenge level of 1000 ng/L. However, the 7.5-hour influent was down to 710 |J,g/L, and the
15-hour influent was even lower, at 650 |J,g/L. This phenomenon was not observed during the
RO membrane challenge, indicating that plating of the mercury on the internal surfaces of the
test rig plumbing was not the cause of the drop in the challenge level.
The mevinphos challenge target was 61 ng/L. The average influent at start-up was only 24 ng/L,
with a 95% confidence interval of 6 |J,g/L. The results from the 7.5-hour and 15-hour influent
samples were higher - 49 |j,g/L and 46 ng/L, respectively.
5.3 Sample Handling
All samples analyzed by the NSF Chemistry Laboratory were labeled with unique ID numbers.
These ID numbers appear on the NSF laboratory reports for the tests. All samples were analyzed
within allowable holding times.
5.4 Analytical Methods QA/QC
The calibrations of all analytical instruments, and the analyses of all parameters complied with
the QA/QC provisions of the NSF International Laboratories Quality Assurance Manual.
27
-------
The NSF QA/QC requirements are all compliant with those given in the USEPA Method or
Standard Method for the parameter. Also, every analytical instrument has an NSF SOP
governing its use.
5.5 Documentation
All laboratory activities were documented using specially prepared laboratory bench sheets and
NSF laboratory reports. Data from the bench sheets and laboratory reports were entered into
Microsoft Excel spreadsheets. These spreadsheets were used to calculate average influents and
effluents, and percent reductions for each challenge chemical. One hundred percent of the data
entered into the spreadsheets was checked by a reviewer to confirm all data and calculations
were correct.
5.6 Data Review
NSF QA/QC staff reviewed the raw data records for compliance with QA/QC requirements.
NSF ETV staff checked 100% of the data in the NSF laboratory reports against the lab bench
sheets..
5.7 Data Quality Indicators
The quality of data generated for this ETV is established through four indicators of data quality:
representativeness, accuracy, precision, and completeness.
5.7.1 Representativeness
Representativeness refers to the degree to which the data accurately and precisely represent the
conditions or characteristics of the parameter represented by the data, or the expected
performance of the RO system under normal use conditions. Representativeness was ensured by
consistent execution of the test protocol for each challenge chemical, including timing of sample
collection, sampling procedures, and sample preservation. Representativeness was also ensured
by using each analytical method at its optimum capability to provide results that represent the
most accurate and precise measurement it is capable of achieving.
5.7.2 Accuracy
Accuracy was quantified as the percent recovery of the parameter in a sample of known quantity.
Accuracy was measured through use of LFB and/or LFM samples of a known quantity, and
certified standards during calibration of the instrument. The following equation was used to
calculate percent recovery:
Percent ReCOVery = 100 X [(Xknown - Xmeasured)/Xknown]
where: Xkn0wn = known concentration of the measured parameter
= measured concentration of parameter
28
-------
The accuracy of the benchtop chlorine, pH, TDS, and turbidity meters were checked daily during
the calibration procedures using certified check standards. For samples analyzed in batches
(gravimetric TDS, TOC, all challenge chemicals), certified QC standards, and LFB and/or LFM
samples were run with each batch.
The percent recoveries of all fortified samples and standards were within the allowable limits for
all analytical methods.
5.7.3 Precision
Precision refers to the degree of mutual agreement among individual measurements and provides
an estimate of random error. One sample per batch was analyzed in duplicate for the gravimetric
TDS and TOC analyses. LFB and/or LFM samples were analyzed to measure precision for the
challenge chemical analyses. Duplicate drinking water samples were analyzed as part of the
daily calibration process for the benchtop chlorine, pH, TDS, and turbidity meters.
Precision of the duplicate analyses was measured by use of the following equation to calculate
relative percent deviation (RPD):
RPD =
:200
where:
Sl = sample analysis result; and
S2 = sample duplicate analysis result.
Precision of the LFB and LFM sample analyses was measured through calculation of the RSD as
follows:
%RSD = S(100)/Xaverage
where: S = standard deviation and
Xaverage = the arithmetic mean of the recovery values.
Standard Deviation is calculated as follows:
Standard Deviation =
n-1
Where: X; = the individual recovery values;
X = the arithmetic mean of then recovery values; and
n = the number of determinations.
All RPDs were within NSF's established allowable limits for each parameter.
29
-------
5.7.4 Completeness
Completeness is the proportion of valid, acceptable data generated using each method as
compared to the requirements of the test/QA plan. The completeness objective for data
generated during verification testing is based on the number of samples collected and analyzed
for each parameter and/or method.
Table 5-1. Completeness Requirements
Number of Samples per Parameter
and/or Method Percent Completeness
(MO 80%
11-50 90%
> 50 95%
Completeness is defined as follows for all measurements:
%C = (V/T)X100
where:
%C = percent completeness;
V = number of measurements judged valid; and
T = total number of measurements.
5.7.4.1 Number of Systems Tested
Twenty systems were tested, as called for in the test/QA plan, giving a completeness
measurement of 100% for this category.
5.7.4.2 Water Chemistry Measurements
All of the planned samples were collected and reported for every parameter but total chlorine.
The technician did not collect total chlorine samples for any of the post-membrane carbon filter
challenges except mevinphos. However, during the timeframe of the carbon filter challenges,
free chlorine in the test water described in Section 3.2.3.2 was measured for other tests. The
DWTS Laboratory provided three measurements: 1.8 mg/L, 2.1 mg/L, and 2.1 mg/L. These
measurements were taken on the same days as the mercury, chloroform, and cesium carbon filter
challenges, respectively. No data was provided for the days of the dichlorvos, dicrotophos, or
mevinphos challenges. While any spikes in the chlorine level much above 2.1 mg/L were
unlikely, the lack of chlorine data does not allow an evaluation of whether the chlorine in the test
water may have impacted the carbon's ability to adsorb the challenge chemicals. A total of 15
samples were not collected out of 50 planned samples. This gives a completeness percentage of
70% for total chlorine.
30
-------
5.7.4.3 Challenge Chemicals
All planned samples were collected, but results for a few were not reported due to analytical
errors.
RO membrane mercury challenge: Triplicate sample 1 for the unit 1 start-up effluent was
an outlier, and was not reported. Thirty-four of thirty-five samples were reported, for a
completeness percentage of 97%.
RO membrane aldicarb challenge: Triplicate sample 3 for the unit 1 post-rest 2nd sample
result was not reported due to an analytical error. Thirty-four of thirty-five samples were
reported, for a completeness percentage of 97%.
RO membrane dichlorvos challenge: The post-rest first draw sample result for unit 1 was
not reported due to an analytical error. Thirty-four of thirty-five samples were reported,
for a completeness percentage of 97%.
31
-------
Chapter 6
References
APHA, AWWA and WEF (1998). Standard Methods for Examination of Water and
Wastewater. 20th ed. Washington, D.C. APHA.
NSF International (2005). NSF/ANSI 53-2005, Drinking water treatment units - health effects.
Ann Arbor, MI, NSF International.
NSF International (2005). NSF/ANSI 58 - 2005, Reverse osmosis drinking water treatment
systems. Ann Arbor, NSF International.
Slovak, Robert (2000). A Practical Application Manual for Residential, Point of Use Reverse
Osmosis Systems. Lisle, IL, Water Quality Association
USEPA (2004). Water Security Research and Technical Support Action Plan. EPA/600/R-
04/063.
32
-------
Appendix A
Conditioning and Chemical Challenges Data Tables
33
-------
Table A-l. RO Membrane Conditioning Water Chemistry Data
Sample Day 1 Day 2 Day 3 Day 4 Day 5 Day 6
Day 7
PH
Temperature (°C)
Total Chlorine (mg/L)
TDS (mg/L)
Turbidity (NTU)
7.7
25
ND (0.05)
750
0.1
7.0
25
ND (0.05)
750
ND(O.l)
7.1
25
ND (0.05)
750
0.1
7.1
25
ND (0.05)
750
0.2
7.0
25
ND (0.05)
750
0.3
7.2
26
ND (0.05)
750
0.1
7.1
25
ND (0.05)
750
ND(O.l)
Table A-2. Post-Membrane Carbon Filter Conditioning Influent Water Chemistry
Sample Point
Group 1, Start-Up
Group 1, 25% of Capacity
Group 1, 50% of Capacity
Influent
Unit 1
Unit 2
Unit3
Unit 4
UnitS
Unite
Unit?
Unit 8
Influent
Unit 1
Unit 2
Unit3
Unit 4
UnitS
Unite
Unit?
Unit 8
Influent
Unit 1
Unit 2
UnitS
Unit 4
UnitS
Unite
Unit?
Unit 8
Chloroform Temperature Total Organic Turbidity
(Hg/L) pH (°C) Carbon (mg/L)(1) (NTU)
340 7.2 21 38 0.1
ND(0.5)
ND(O.S)
ND(0.5)
ND(O.S)
ND(0.5)
13
ND(O.S)
ND(0.5)
310 7.2 20 38 0.1
ND(O.S)
ND(0.5)
ND(O.S)
ND(0.5)
ND(O.S)
22
ND(0.5)
ND(O.S)
310 7.3 20 38 ND(O.l)
ND(0.5)
ND(O.S)
ND(0.5)
ND(O.S)
ND(0.5)
24
ND(O.S)
ND(0.5)
Group 2, Start-Up
Group 2, 25% of Capacity
Group 2, 50% of Capacity
Influent
Unit 9
Unit 10
Unit 11
Unit 12
Unit 13
Unit 14
Unit 15
Influent
Unit 9
Unit 10
Unit 11
Unit 12
Unit 13
Unit 14
Unit 15
Influent
Unit 9
Unit 10
Unit 11
Unit 12
Unit 13
Unit 14
Unit 15
310
2.6
12
ND(0.5)
9.0
ND(0.5)
9.0
34
270
9.1
23
30
21
ND(0.5)
21
68
360
36
29
ND(0.5)
30
ND(0.5)
36
73
7.3
20
38
0.1
7.2
20
37
ND(O.l)
7.4
21
42
0.2
(1) TOC measured after addition of chloroform, which was in a methanol solution. High TOC readings were due to
the methanol.
34
-------
Table A-3. RO Membrane TDS Reduction System Check Data
Sample
Influent
Unitl
Unit 2
Unit3
Unit 4
UnitS
Unite
Unit?
UnitS
Unit 9
Unit 10
Unit 11
Unit 12
Unit 13
Unit 14
Unit 15
Unit 16
Unit 17
Unit 18
Unit 19
Unit 20
Unit 21
Unit 22
TDS
Total Influent Effluent
Temperature Chlorine Turbidity TDS Sample 1
pH (°C) (mg/L) (NTU) (mg/L) (mg/L)
7.2 25 ND(0.05) ND(O.l) 750
68
68
79
100
76
58
68
70
64
67
59
99
69
66
68
74
62
67
67
65
66
66
TDS
Effluent
Sample 2
(mg/L)
70
68
81
100
77
60
68
70
65
68
60
100
70
67
69
76
62
67
68
66
67
67
TDS
Effluent
Sample 3
(mg/L)
70
69
81
100
77
59
68
71
65
68
60
100
70
67
69
76
62
67
68
67
67
67
Percent
Reduction
91
91
89
87
90
92
91
91
91
91
92
87
91
91
91
90
92
91
91
91
91
91
35
-------
Table A-4. RO Membrane Inorganic Chemicals Challenge Data
Sample
Start-up Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Start-up Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Start-up Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
3rd Tank Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
3rd Tank Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
3rd Tank Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
5th Tank Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
5th Tank Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
5th Tank Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Post-Rest 1st Draw, Unit 1
Post-Rest 1st Draw, Unit 2
Post-Rest 2nd Sample, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Post-Rest 2nd Sample, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Cadmium
(Hg/L)
950
950
940
950
9.9
10
9.7
9.9
43
51
51
48
950
930
1000
960
48
9.5
11
23
57
59
12
43
960
980
950
960
10
9.6
11
10
56
55
54
55
10
61
11
12
11
11
52
62
55
56
Cesium
(re/L)
920
920
910
920
110
110
110
110
130
150
150
140
930
910
960
930
180
150
150
160
220
210
150
190
930
920
920
920
160
140
160
150
220
200
220
210
170
200
160
160
160
160
200
210
210
210
Mercury
(MS/L)
1000
1000
1100
1000
2000(1)
980
970
980
890
980
710
860
1100
1000
1100
1100
1000
960
1400
1100
1000
910
1000
970
1300
1200
1200
1200
1100
1000
1100
1100
1100
1000
1200
1100
1000
930
980
1000
1000
990
1000
970
1000
990
Strontium
(re/L)
960
950
950
950
9
9
9
9
53
48
48
50
950
930
1000
960
59
10
11
27
59
63
10
44
960
970
950
960
10
10
10
10
57
57
57
57
10
55
10
10
10
10
59
5
57
57
(1) Sample result not included in mean calculation due to analytical error.
36
-------
Table A-5. RO Membrane Organic Chemical Challenge Data
Aldicarb Benzene Carbofuran Chloroform Dichlorvos Dicrotophos Fenamiphos Mevinphos Oxamyl Strychnine
Sample
Start-up Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Start-up Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Start-up Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
3rd Tank Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
3rd Tank Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
3rd Tank Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
5th Tank Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
5th Tank Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
5th Tank Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Post-Rest 1st Draw, Unit 1
Post-Rest 1st Draw, Unit 2
Post-Rest 2nd Sample, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Post-Rest 2nd Sample, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
(Hg/L)
1100
1100
1000
1100
11
11
11
11
21
21
21
(|xg/L)
920
1100
930
980
ND(0.5)
ND(0.5)
ND(0.5)
ND (0.5)
ND(0.5)
ND(0.5)
ND(0.5)
21 ND (0.5)
980
1000
950
980
25
25
24
25
14
14
14
14
1000
1000
1000
1000
16
16
17
16
27
27
27
27
16
27
16
16
1600(1)
16
26
27
26
26
1100
990
1200
1100
7.3
8.4
7.4
7.7
3.0
2.7
3.5
3.1
930
860
990
930
15
13
18
15
8.3
7.0
5.6
7.0
9.7
7.1
17
10
11
13
8.2
5.5
7.3
7.0
(|xg/L)
1100
1100
1100
1100
17
17
17
17
15
15
16
15
1100
1100
1100
1100
20
20
19
20
18
18
18
18
1100
1100
1100
1100
20
20
20
20
18
18
19
18
21
19
20
21
20
20
19
19
20
19
(|xg/L)
1100
1100
1100
1100
1.7
2.0
1.9
2.5
2.5
2.6
2.2
2.4
1100
1100
1100
1100
43
47
45
45
59
58
60
59
1100
1100
1100
1100
67
68
61
65
85
89
86
87
74
100
82
81
77
80
100
100
100
100
(|xg/L)
1500
1300
1300
1400
43
39
19
34
42
35
24
34
1300
1300
1300
1300
66
64
65
65
71
72
72
72
1300
1300
1400
1300
83
76
85
81
93
76
88
86
#
87
71
80
70
74
86
81
94
87
(|xg/L)
1100
1100
1100
1100
20
30
30
30
30
60
60
50
1200
1100
1100
1100
30
40
40
38
70
70
80
70
1000
1000
1000
1000
50
40
50
50
80
70
90
80
50
80
50
50
40
50
80
70
80
80
(|xg/L)
860
920
950
910
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
1000
930
920
950
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
860
1000
930
930
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
ND(4)
5
5
5
5
5
5
4
4
ND(4)
4
(|xg/L)
1300
1200
1200
1200
29
32
33
31
40
42
40
41
1300
1200
1200
1200
43
42
41
42
54
53
52
53
1200
1200
1300
1200
50
46
40
45
53
56
51
53
46
54
47
42
39
43
55
51
61
56
(|xg/L)
960
960
940
950
10
9
10
10
6
6
6
6
1100
1000
980
1000
11
11
11
11
8
8
8
8
950
980
990
970
12
11
11
11
9
9
9
9
11
9
11
11
11
11
9
9
9
9
(|xg/L)
1100
1100
1100
1100
ND(5)
ND (5)
ND(5)
ND(5)
10
ND(5)
ND(5)
7
1100
1100
1100
1100
8
7
8
8
11
11
11
11
1100
1100
1100
1100
14
13
13
13
8
8
9
8
8
13
9
12
9
10
15
14
13
14
(1) Sample result not included in mean calculation due to analytical error.
37
-------
Table A-6. RO Membrane Challenges Water Chemistry Data
Sample
Start-up Influent
PH
Temperature (°C)
Total Chlorine (mg/L)
Turbidity (NTU)
5th Tank Influent
PH
Temperature (°C)
Total Chlorine (mg/L)
Turbidity (NTU)
Cd, Cs, Sr
Challenge
6.3
24
ND (0.05)
0.1
6.2
25
ND (0.05)
ND(O.l)
Mercury
Challenge
6.5
25
ND (0.05)
ND(O.l)
6.4
24
ND (0.05)
0.2
Aldicarb Benzene
Challenge Challenge
7.5 7.6
25 25
ND (0.05) ND (0.05)
0.1 0.1
7.5 7.2
24 25
ND (0.05) ND (0.05)
ND(O.l) ND(O.l)
Carbofuran Chloroform
Challenge Challenge
7.6
24
ND (0.05)
ND(O.l)
7.5
25
ND (0.05)
0.1
7.1
26
ND (0.05)
ND(O.l)
7.2
25
ND (0.05)
0.2
Dichlorvos
Challenge
7.4
25
ND (0.05)
ND(O.l)
7.4
25
ND (0.05)
ND(O.l)
Dicrotophos
Challenge
7.7
25
ND (0.05)
ND(O.l)
7.2
25
ND (0.05)
ND(O.l)
Fenamiphos
Challenge
7.3
25
ND (0.05)
0.1
7.1
25
ND (0.05)
0.1
Mevinphos
Challenge
7.3
25
ND (0.05)
0.2
7.3
25
ND (0.05)
0.3
Oxamyl
Challenge
7.3
24
ND (0.05)
ND(O.l)
7.2
25
ND (0.05)
0.2
Strychnine
Challenge
7.2
24
ND (0.05)
0.4
7.1
24
ND (0.05)
ND(O.l)
Table A-7. RO Membrane Inorganic Chemicals Challenge Reject Water Data
Sample
Cadmium
(Mg/L)
Cesium
(Mg/L)
Mercury
(Mg/L)
Strontium
(Mg/L)
Start-up
Duplicate Sample 1 1200 1100 970 1200
Duplicate Sample 2 1200 1100 780 1200
Mean 1200 1100 880 1200
1/2 Through First Tank
Duplicate Sample 1 1100 1000 1400 1100
Duplicate Sample 2 1200 1100 1000 1200
Mean 1200 1100 1200 1200
3/4 Through First Tank
Duplicate Sample 1 1100 1000 990 1100
Duplicate Sample 2 1100 1000 1000 1100
Mean 1100 1000 1000 1100
1/2 Through 5th Tank
Duplicate Sample 1 1100 1000 1200 1100
Duplicate Sample 2 1100 1000 1200 1100
Mean 1100 1000 1200 1100
Table A-8. RO Membrane Organic Chemical Challenges Reject Water Data
Sample
Aldicarb Benzene Carbofuran Chloroform Dichlorvos Dicrotophos Fenamiphos Mevinphos
(Mg/L) (Mg/L) (Mg/L) (Mg/L) (Mg/L) (Mg/L) (Mg/L) (Mg/L)
Oxamyl Strychnine
(Mg/L) (Mg/L)
Start-up
Duplicate Sample 1 1200 790 1400 830 1600 1300 1100 1600 1100 1400
Duplicate Sample 2 1200 990 1500 970 1500 1400 1400 1600 1100 1400
Mean 1200 890 1500 900 1600 1400 1300 1600 1100 1400
1/2 Through First Tank
Duplicate Sample 1 1200 840 1400 940 1500 1300 1200 1400 1200 1400
Duplicate Sample 2 1200 970 1400 960 1500 1200 1000 1400 1200 1400
Mean 1200 910 1400 950 1500 1300 1100 1400 1200 1400
3/4 Through First Tank
Duplicate Sample 1 1100 1100 1400 970 1400 1300 1100 1500 1300 1300
Duplicate Sample 2 1100 860 1400 1000 1500 1400 1300 1500 1200 1400
Mean 1100 980 1400 990 1500 1400 1200 1500 1300 1400
1/2 Through 5th Tank
Duplicate Sample 1 1100 1200 1300 1000 1600 1300 1000 1300 1100 1200
Duplicate Sample 2 1100 1200 1300 1400 1400 1100 890 1400 1100 1200
Mean 1100 1200 1300 1200 1500 1200 950 1400 1100 1200
38
-------
Table A-9. Post-Membrane Carbon Filter Challenges Data
Cesium Mercury Chloroform Dichlorvos Dicrotophos Mevinphos
Sample
Target Influent Level
Start-up Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Start-up Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
Start-up Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
7.5 Hours Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
7.5 Hours Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
7.5 Hours Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
1 5 Hours Influent
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
15 Hours Effluent, Unit 1
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
15 Hours Effluent, Unit 2
Triplicate Sample 1
Triplicate Sample 2
Triplicate Sample 3
Mean
220
230
230
230
230
210
220
210
210
200
200
200
200
220
230
230
230
220
220
210
220
240
230
230
230
230
230
220
230
230
230
230
230
220
230
230
230
1000
890
910
940
910
41
43
44
43
18
24
22
21
750
680
690
710
46
47
47
47
26
26
26
26
660
620
670
650
48
43
47
46
28
27
25
27
100
100
97
100
99
ND(0.5)
ND(0.5)
ND(0.5)
ND (0.5)
ND(0.5)
ND(0.5)
ND(0.5)
ND (0.5)
100
100
110
100
ND(0.5)
ND(0.5)
ND(0.5)
ND (0.5)
ND(0.5)
ND(0.5)
ND(0.5)
ND (0.5)
100
100
100
100
1.7
1.6
1.6
1.6
ND(0.5)
ND(0.5)
ND(0.5)
ND (0.5)
95
96
110
100
100
ND (0.2)
ND (0.2)
ND (0.2)
ND (0.2)
5.1
5.5
15
8.5
110
100
100
100
ND (0.2)
ND (0.2)
0.5
0.3
7.8
7.3
6.7
7.3
100
100
100
100
0.2
ND (0.2)
ND (0.2)
0.2
6.7
7.3
7.7
7.2
90
80
80
90
SO
ND (10)
ND (10)
ND (10)
ND (10)
ND(10)
ND(10)
ND(10)
ND (10)
100
100
80
90
ND (20)(1)
ND (10)
ND (10)
10
ND(10)
ND(10)
ND(10)
ND (10)
90
80
90
90
ND (10)
ND(10)
ND (10)
ND (10)
ND(10)
ND (10)
ND (10)
ND (10)
61
28
26
18
24
ND (0.2)
ND (0.2)
ND (0.2)
ND (0.2)
2.2
3.1
2.7
2.7
51
46
50
49
ND (0.2)
ND (0.2)
ND (0.2)
ND (0.2)
4.6
4.2
4.1
4.3
43
47
47
46
ND (0.2)
0.5
ND (0.2)
0.3
5.1
5.1
5.2
5.1
(1) Detection limit higher due to dilution of the sample prior to analysis.
39
-------
Table A-10. Post-Membrane Carbon Filter Challenges Water Chemistry Data
Sample
Start-up Influent
PH
Temperature (°C)
Total Chlorine (mg/L)
TOC (mg/L)
TDS (mg/L)
Turbidity (NTU)
7.5 Hour Influent
PH
Temperature (°C)
Total Chlorine (mg/L)
TOC (mg/L)
TDS (mg/L)
Turbidity (NTU)
1 5 Hour Influent
PH
Temperature (°C)
Total Chlorine (mg/L)
TOC (mg/L)
TDS (mg/L)
Turbidity (NTU)
Challenge
7.3
21
#
2.9
450
0.2
7.3
20
#
2.3
370
0.2
7.3
21
#
2.1
360
0.3
Challenge
7.5
20
#
2.5
310
0.1
7.3
22
#
2.6
320
0.1
7.3
21
#
2.8
360
0.1
Challenge
7.5
20
#
2.6
340
ND(O.l)
7.3
21
#
29(D
320
0.3
7.4
21
#
2.7
340
0.2
Challenge
7.3
20
#
2.7
390
0.1
7.3
20
#
2.2
320
0.3
7.3
20
#
2.5
330
0.1
Challenge
7.3
20
#
2.2
310
0.1
7.3
21
#
2.3
300
0.1
7.3
22
#
2.3
310
0.1
Challenge
7.3
20
1.6
2.3
320
0.1
7.2
21
1.6
2.3
310
0.1
7.3
21
2.4
2.3
320
0.1
# Technician missed sample collection
(1) TOC measured after addition of chloroform, which was in a methanol solution. High TOC reading was due to
the methanol.
40
------- |