![[logo] US EPA](../gif/logo_epaseal.gif){kind=logo}
Portland Water Bureau (XLC)
May 22, 1997 Letter to Philip Milliam from K. Babette Faris
May 22, 1997WQ 1.11.7
Philip G. Millam
Director, Office of Water Region 10
OW - 136
1200 Sixth Avenue
Seattle, WA 98191
SUBJECT: Project XL Proposal for Lead and Copper Rule Compliance
Dear Mr. Millam:
In November 1996, the Portland Water Bureau provided an informational briefing on our proposed Lead Hazard Reduction Program to the EPA Region 10 office. A number of questions were posed by Region 10 subsequent to that meeting as listed in your letter of 12/04/96 (attached). Although some of these questions have been addressed through conversations with Region 10 staff and in our Project XL proposal, this letter includes responses to the questions based on current information relating to the Lead Hazard Reduction Program (LHRP).
Some of the questions refer to the draft LHRP Report dated 11/05/96. Please note that these responses refer to a final version of the LHRP report dated 12/12/96 and an updated description of the Home Lead Hazard Reduction component of the LHRP dated 03/13/97. Both of these documents were submitted as part of our Project XL proposal submitted in March.
1. It is not clear to us why you believe corrosion control treatment would require the addition of sodium hydroxide, CO2 and soda ash. In our opinion, addition of sodium hydroxide and CO2, without the use of soda ash, would be effective, as would be soda ash and CO2 without the addition of a sodium hydroxide. Discussion of the rationale for using all three additives would be helpful.
The LCR corrosion control study1 and the treatment facility pre-design report2 indicate that "optimal" treatment to minimize lead and copper solubility and provide a stable pH within the distribution system would involve raising pH to 9.0-9.5 and alkalinity to 20-25 mg/L as CaCO3.
The pre-design report recommends that the treatment facility include three chemical feed systems that could be used alone or in combination: sodium hydroxide (NaOH), soda ash (Na2CO3), and carbon dioxide (CO2). Such a facility would provide the capability to meet a range of pH and alkalinity targets with the lowest operating costs.
The use of NaOH+CO2 could be used to achieve "optimal" water quality targets of pH 9.0-9.5 and alkalinity 20-25 mg/L as CaCO3. However, these water quality targets could be achieved at a much lower cost using Na2CO3+CO2 or Na2CO3+NaOH. Chemical doses and costs for various water quality operating targets are presented in the pre-design report and a related memo from Montgomery Watson3 (attached).
2. Are the water treatment costs identified in Table 6-1 of the draft report relatively firm, or are they merely preliminary estimates?
The water treatment costs listed in Table 6-1 of the LHRP report4 are updated in the following table.
Capital costs listed for the three-chemical feed treatment facility are +/- 25% planning level estimates. Capital costs listed for the treatment facility to feed caustic soda are approximate costs for actual facility design and construction.
Operating costs listed are +/- 15%.
Updated Cost Estimates for Water Treatment (5/97) (a)
Required LCR Approach
Proposed LHRP Approach
Water Quality Targets
pH up to 9.5;alkalinity up to 25 mg/L
pH 7.5No alkalinity target
Capital CostConstruction
Engineering Services
Total
Na2CO3, NaOH, CO2 feeds(b) $3,210,000
$965,000
$4,175,000
NaOH feed(c)$1,210,000
$365,000
$1,575,000
1997 Operating CostChemicals (d)
Labor
Power (I)
Maintenance (j)
Subtotal
Contingencies (20%)
TOTAL
(Cost in Table 6-14)
(e) $745,000(g) $180,000
$ 15,000
$ 64,200
$1,004,200
$200,840
$1,205,040
$ 1,235,520
(f) $150,500(h) $120,000
$7,500
$24,200
$302,200
$60,440
$362,640
$392,000
(a) Based on format of Table D-42
(b) Planning level estimates from P. Kreft to B. Faris, 12/96
8 Approximate cost of NaOH feed facility constructed; from D. Peters to B. Faris, 12/96
(d) Based on average Bull Run chloraminated water quality of pH 6.8 and alkalinity 6.8 mg/L and on an annual average flow of 130 MGD and the following chemical costs: NaOH @ $0.20/lb, Na2CO3 @ $0.09/lb, CO2 @ $0.05/lb
(e) Based on use of Na2CO3+CO2 or Na2CO3+NaOH for target pH 9.5 and
target alkalinity 25 mg/L (See Table D-33).
(f) Based on use of NaOH (see Table D-33)
(g) Based on 3 FTEs (h) Based on 2 FTEs
(I) Based on power cost of $0.06/kw-hr (j) 2% of construction cost annually
3. A decision to raise pH using sodium hydroxide has apparently been made. Would sodium hydroxide without CO2 be effective for raising the pH to 9.0 - 9.5?
As discussed previously, both the LCR corrosion control study and the treatment facility pre-design report indicate that "optimal" treatment to minimize lead and copper solubility and provide a stable pH within the distribution system would involve raising pH to 9.0-9.5 and raising alkalinity to at least 20-25 mg/L as CaCO3.
NaOH alone could be used to raise pH to 9.0-9.5; however, use of NaOH alone would provide alkalinity levels less than 15 mg/L as CaCO3, outside the recommended range of 20-25 mg/L as CaCO3. Water quality targets for "optimal" corrosion control treatment could be achieved at the least cost using Na2CO3+CO2 or Na2CO3+NaOH as indicated in Table D-33.
4. How would treatment costs (both capital and annual) compare if only sodium hydroxide and CO2 were to be used to raise pH to 9.0 - 9.5 or if sodium hydroxide alone was to be used to raise pH to 9.0 - 9.5?
As discussed above, NaOH alone could be used to raise pH to 9.0-9.5 if alkalinity below 15 mg/L as CaCO3 was acceptable; use of CO2 would not be necessary in this case. Cost estimates for this scenario are shown in the table that follows.
However, if in addition to a pH target of 9.0 - 9.5, an alkalinity target of 15-25 mg/L was desired to maintain a stable pH, use of NaOH+CO2 would be an option, although a relatively expensive one. Cost estimates for this scenario are also shown in the table that follows. As Table D-33 indicates, the chemical cost of using NaOH+CO2 to achieve pH 9.0-9.5 and alkalinity 15-25 mg/L would be much higher than the cost of using Na2CO3+CO2 to achieve these goals.
Capital costs listed for the treatment facility to feed caustic soda and carbon dioxide are +/- 25% planning level estimates. Capital costs listed for the treatment facility to feed caustic soda are approximate costs for actual facility design and construction. Operating costs listed are +/- 15%.
Cost Estimates for Water Treatment (5/97) (a)
NaOH and CO2 Feed Facility
NaOH Feed Facility
Water Quality Targets
pH 9.0 - 9.5alkalinity 20-25 mg/L
pH 9.0 - 9.5no alkalinity target (alk<15 mg/L)
Capital CostConstruction
Engineering Services
Total
(b) $1,710,000$513,000
$2,223,000
(c)$1,210,000$365,000
$1,575,000
1997 Operating CostChemicals (d)
Labor
Power (I)
Maintenance (j)
Subtotal
Contingencies (20%)
TOTAL
(e) $1,019,000 - 1,461,000(g) $150,000
$ 11,250
$ 34,200
$1,214,450 - 1,656,450
$242,890 - 331,290
$1,457,340 - 1,987,740
(f) $233,500 - 299,000(h) $120,000
$7,500
$24,200
$385,200 - 450,700
$77,040 - 90,140
$462,240 - 540,840
(a) Based on format of Table D-42
(b) Planning level estimates from P. Kreft to B. Faris, 5/96
8 Approximate cost of NaOH feed facility constructed; from D. Peters to B. Faris, 12/96
(d) Based on average Bull Run chloraminated water quality of pH 6.8 and alkalinity 6.8 mg/L and on an annual average flow of 130 MGD and the following chemical costs: NaOH @ $0.20/lb, Na2CO3 @ $0.09/lb, CO2 @ $0.05/lb
(e) Based on use of NaOH + CO2 (see Table D-33).
(f) Based on use of NaOH (see Table D-33)
(g) Based on 2 FTEs (h) Based on 2.5 FTEs
(I) Based on power cost of $0.06/kw-hr (j) 2% of construction cost annually
5. Success of the Lead Hazard Reduction Program (LHRP) relies heavily on parents' commitment to continuously implement the lead intervention measures identified in the work plan developed by the LHRP staff. If the lead hazards are not actually removed, but instead are to be "controlled" (for example, by wet-mopping and cleaning window sills at a certain frequency), what kind of follow-up program will be developed to ascertain that these intervention measures are continuously implemented? We are concerned that these intervention measures may be implemented only temporarily rather than for as long as children live in the house for which the intervention work plan was developed.
The Home Lead Risk Reduction component of our LHRP will implement and evaluate in-place management or abatement practices in homes where significant lead exposure risks are identified. These practices include repairing damaged and/or deteriorated paint surfaces; specialized cleaning of walls, window wells and sills, and furniture; repainting or encapsulation to provide a durable surface; and in-home resident education. The use of in-place management practices to remove and/or control dust, rather than complete removal of intact lead-based paint, is recommended by HUD in recent reports dealing with the dangers of lead-based paint in the nation's housing stock 5,6.
Currently, we plan to evaluate the short- and long-term effectiveness of these interventions by monitoring dust lead and conducting interviews with residents before the intervention, and immediately, 6-months and 18-months after the intervention. Based on periodic evaluations of these results by stakeholders, our program will be modified as necessary to enhance effectiveness. Evaluation will be conducted by the OHD/MCHD Program Design and Evaluation Services Group. About 30% of the initial year's operating budget for this component is for evaluation services.
The outcomes of the Home Lead Hazard Risk Reduction Component will add to the national fund of knowledge about reducing home lead hazards because it will address several areas where additional data is needed. In particular, information is generally lacking on the effectiveness of lead hazard interventions 1) that attempt to prevent elevated blood lead levels before they occur 2) among children with blood lead levels <= 20 ug/dL and 3) beyond one year following the intervention7.
6. On page 45 of the draft report, the suggestion is made that the program would supply training and basic supplies to the resident or rental property owner to control the hazard, mentioning paint abatement materials such as plastic sheeting and tape. This implies that the program would encourage owners to do their own lead-based paint abatement. Information available to us indicates that nearly every case of serious childhood lead poisoning not attributed to the direct ingestion of paint chips has occurred in a home where the occupant is doing the remodeling. Could your LHRP pay for professionally trained crews to conduct the necessary lead-based paint abatement instead of having the occupants do the work?
Yes. As stated above, in homes where significant lead exposure risks are identified, cost-effective in-place management or abatement techniques will be used to reduce lead-based paint hazards, including safe repair of deteriorated painted surfaces, repainting, specialized cleaning, and use of encapsulants.
In March 1997, a decision was made to implement the Home Lead Hazard Reduction Component through the Multnomah County Health Department with an AmeriCorps program called CLEARCorps (Community Lead Education and Reduction Corps). Work will be conducted by MCHD staff and AmeriCorps members certified as lead abatement workers, lead abatement supervisors, lead inspectors, and lead risk assessors. These individuals will receive training through the Western Regional Lead Training Center (WRLTC) at Oregon State University.
All eight CLEARCorps team members will complete the lead worker training class. The CLEARCorps team leader and assistant team leader will also complete the lead abatement training for supervisors and contractors. The CLEARCorps team supervisor will be a certified lead inspector and risk assessor. Additional technical supports to the CLEARCorps team for home lead risk evaluation will be provided by an additional licensed lead risk assessor at the MCHD.
7. Table 2-3 of the draft report includes lead information based on the results of Lead and Copper Rule monitoring conducted by the Portland Water Bureau. If possible, please provide this same information for other water systems within the Bull Run service area.
Results of initial lead and copper tap sampling required by the LCR for Portland and its wholesale water customers are provided in the table that follows.
Lead and Copper Rule: Lead and Copper at the Tap - 1992 Initial Monitoring Period
Name Req'd
no. samples1st round -Initial monitoring
periodActual no. of samples Pb 90th %tile Cu 90th %tile 2nd round Initial monitoring period Actual no. of samples Pb 90th %tile Cu 90th %tile
Burlington WD
10
Jul-Dec 93
10
0.011
1.3
GNR Corp
5
Jul-Dec 93
5
0.008
0.18
Gresham, City of
60
Jul-Dec 92
60
0.041
1.4
(2)
Lake Grove WD
20
Jul-Dec 93
20
0.062
1.1
Lorna WD
10
Jul-Dec 93
10
0.015
0.13
Lusted
20
Jul-Dec 93
20
0.007
0.9
Palatine Hill WD
20
Jul-Dec 93
21
0.075
1.9
Pleasant Home WD
20
Jul-Dec 93
20
0.030
1.9
Portland, City of
100
Jan-Jun92
126
0.044
1.8
Jul-Dec 92
125
0.053
1.3
Powell Valley Road WD
60
Jul-Dec 92
60
0.035
1.3
(2)
Raleigh WD
20
Jul-Dec 92
30
0.034
1.3
Rockwood WD
60
Jul-Dec 92
61
0.037
1.8
(2)
Skyview Acres WD
5
Jul-Dec 93
5
0.022
1.3
Tualatin, City of
60
Jul-Dec 92
60
0.043
0.85
(2)
Tualatin Valley WD
100
Jan-Jun92
102
0.028
1.4
Jul-Dec 92
102
0.029 (3)
0.099 (3)
Valley View WD
10
Jul-Dec 93
9
0.039
1.1
West Slope WD
60
Jul-Dec 92
75
0.039
1.2
(2)
79
0.037
1.3(1) Source: OHD
(2) OHD waived requirement for 2nd round of monitoring for medium systems that exceeded lead and/or copper action levels in first round of monitoring
(3) Sources of water other than Bull Run in use at the time of monitoring
8. Will your expanded free lead-in-water testing and follow-up program also cover apartments, schools, and day cares?
Yes.
Portland has previously worked with the Portland Public Schools on the issue of lead in drinking water. In 1992, we provided lead testing of water samples collected from more than 10 schools. In 1995, we conducted a study to determine the effectiveness of replacing existing classroom bubblers with lead-free models in reducing standing water lead levels8. Also in 1995, we conducted lead-in-water testing in about 100 pre-schools and child day care centers in the Bull Run service area9.
Please feel free to contact me at (206) 823-7498 if you would like additional information related to this group of questions.
Sincerely,
K. Babette Faris, P.E.
Water Quality Engineerc: EPA Region 10: Bill Glasser, Wendy Marshall
Economic and Engineering Services: Glen Boyd
Montgomery Watson: Pete Kreft
attachments
Notes:
1 Montgomery Watson and Economic and Engineering Services, 1994. Lead and Copper Rule Corrosion Control Study for the City of Portland Bureau of Water Works
2 Montgomery Watson and Economic and Engineering Services, 1996. Corrosion Control Treatment Facility Preliminary Design Report, City of Portland Bureau of Water Works.
3 Memo from P. Kreft to B. Faris dated 5/19/97 (attached).
4 Economic and Engineering Services and City of Portland Bureau of Water Works, December 12, 1996. Lead Hazard Reduction Program Report.
5 U.S. Dept. Of Housing and Urban Development, 1990. "Comprehensive and Workable Plan for the Abatement of Lead-Based Paint in Privately Owned Housing".
6 U.S. Dept. Of Housing and Urban Development, July, 1995. "Putting the Pieces Together: Controlling Lead Hazards in the Nation's Housing : Final Report of the Lead-based Paint Hazard Reduction and Financing Task Force".
7 U.S. EPA, 1995. Review of Studies Addressing Lead Abatement Effectiveness. Washington, DC.
8 Economic and Engineering Services, September 1995. Technical Memorandum No. 6: Bubbler Replacement Study City of Portland Bureau of Water Works.
9 Economic and Engineering Services, April 1995. Draft Technical Memorandum No. 4: Portland Area Preschool Survey City of Portland Bureau of Water Works.