2011 Progress Report: Evaluation of Lead Service Line Lining and Coating TechnologiesEPA Grant Number: R834865
Title: Evaluation of Lead Service Line Lining and Coating Technologies
Investigators: Case, Traci L. , Adams, Craig D. , Peltier, Edward F. , Randtke, Stephen J. , Roberson, J. Alan
Institution: Water Research Foundation , American Water Works Association , University of Kansas
EPA Project Officer: Hiscock, Michael
Project Period: January 1, 2011 through December 31, 2016
Project Period Covered by this Report: January 1, 2011 through December 31,2011
Project Amount: $600,000
RFA: Advancing Public Health Protection through Water Infrastructure Sustainability (2009) RFA Text | Recipients Lists
Research Category: Drinking Water , Water
The primary objectives of this research project are to:
- comprehensively evaluate lead service line (LSL) lining and coating technologies as alternatives to full or partial LSL replacement and as a means of protecting and repairing both lead and copper service lines; and
- provide water utilities, engineering consultants, state regulators, consumers, and other interested parties with the information and supporting documentation needed to make informed decisions regarding lining and coating of both lead and copper service lines.
(May 31-July 31, 2011)
Information Gathering (Tasks 1 and 2)
During this reporting period, the research team began work in earnest on Task 1 (Gather and Evaluate Existing Information and Identify Issues) and Task 2 (Acquire and Evaluate Monitoring Data). Activities associated with these tasks included: delving into the scientific literature; acquiring and reviewing relevant ASTM, AWWA, and NSF International standards; and contacting utilities, including the participating utilities listed on the first page of this report as well as the City of Calgary Water Services, Madison Water Utility, the North Shore Water Commission (Wisconsin), and DC Water. The majority of these utilities have either sent us information or have promised to do so. In addition, a number of meetings were held to gather additional information.
Development of Methods and Protocols
The research team has begun developing the sampling protocols, analytical methods and experimental protocols that will be needed to undertake Tasks 2, 3, and 4 (listed below), i.e., to collect samples from existing installations of lining and coating technologies and to conduct lab and demonstration experiments.
We are developing a protocol for Pb measurement using graphite furnace atomic absorption spectroscopy. Our initial work has been to establish detection and quantitation limits for Pb in representative samples, and we are analyzing several matrix modifiers to determine which one yields the best detection limits and reproducibility.
Based on the information obtained to date on lining and coating technologies currently available for LSLs, we decided to focus our initial laboratory efforts on epoxy coatings. Epoxy coating is a well established technology, has been tested by several utilities in the U.S. having LSLs, and is widely used for other purposes, such as protecting pipes of other sizes and composition. Furthermore, there is considerable current interest in bisphenol-a (BPA), a major ingredient of epoxies.
We are developing a method for determining BPA and other bisphenol compounds used or being considered for use by manufacturers of epoxies and other plastic materials, including bisphenol-b (BPB), bisphenol-d (BPD), bisphenol-e (BPE), bisphenol-f (BPF), and bisphenol-s (BPS). These compounds were selected for investigation of degradation by free chlorine and monochloramine (MCL). Current literature lacks oxidation studies for the alternative bisphenols and BPA has not been explored in regards to MCL. Completed during this reporting period was optimization of the LC/MS method that will be used to analyze samples in later oxidation studies.
The mass spectrometer parameters were optimized in positive and negative mode for BPA; negative mode ionization was chosen for all analytes due to increased intensity and stability of the fragment ions. Liquid chromatography mobile phases of acetonitrile/water and methanol/water were investigated and gradient elution with methanol/water was selected since it produced intense well defined chromatographic peaks. The additives ammonium formate and ammonium acetate were explored with the methanol/water gradient but were eliminated since ionization was suppressed. HPLC and LC/MS grades of methanol were compared; LC/MS grade was chosen since it produced a less noisy background.
The internal standard (IS) bisphenol-a D16 (BPA-D16) was selected to be used during quantification to correct for ionization variability and matrix effects. The IS is being pre-injected on the LC column to reduce contact time with the oxidants and avoid IS degradation. Linear calibration curves based on the ratio of the IS peak area and the analyte peak area will be used for quantification. After running one more set of samples, we will have the data needed to calculate an MDL for each the various analytes.
Assessment of Actual Versus Planned Progress for Each Task
This research project is designed to accomplish its objectives (stated on the title page) by completing the following seven tasks:
Task 1: Gather and Evaluate Existing Information and Identify Issues
Task 2: Acquire and Evaluate Monitoring Data
Task 3: Conduct Laboratory Studies
Task 4: Design and Conduct Demonstration Experiments
Task 5: Build New Case Studies
Task 6: Evaluate Available Lining and Coating Technologies
Task 7: Develop Recommendations for Stakeholders
Work on Tasks 1, 2, 3, and 6 is underway, and methods and protocols are being developed for Tasks 2, 3, and 4, as described above. Overall, the project is on schedule and progress to date is consistent with the revised project implementation schedule.
(August 1-October 31, 2011)
Information Gathering (Tasks 1 and 2)
During this reporting period, the research team continued working on Task 1 (Gather and Evaluate Existing Information and Identify Issues) and Task 2 (Acquire and Evaluate Monitoring Data). Activities associated with these tasks included: continuing review of scientific literature; initiating a review of relevant standards and practices in other countries; and contacting utilities and vendors for information.
Sample Analysis and Laboratory and Demonstration Studies (Tasks 2, 3 and 4)
The research team continued developing the sampling protocols, analytical methods and experimental protocols needed to undertake Tasks 2, 3, and 4, i.e., to collect samples from existing installations of lining and coating technologies and to conduct lab and demonstration experiments. The analytical methods for general water quality parameters (pH, alkalinity, major ions, residual chlorine, and TOC) are relatively straightforward, so work to date has focused on purchasing electrodes and reagents, preparing standard and reagent solutions, preparing written standard operating protocols (SOPs), and training graduate research assistants. Most of our methods development work this past quarter has focused on the following tasks: 1) fine-tuning our graphite furnace atomic absorption (GFAA) method for lead (Pb); 2) researching methods and developing method performance objectives for antimony (Sb); and 3) developing and optimizing LC/MS methods for selected organic chemicals, especially bisphenols and their chlorine degradation products.
Although the action level for Pb is 15 μg/L, the MCL goal is zero. Also, the lead and copper rule (LCR) is currently under review, and it is conceivable that the MCL for lead may be lowered in the future. Therefore, we decided it would be desirable to develop a method having a method detection level (MDL) well below the current action level. Given the difficulty of determining very low lead levels in water samples, we decided that a reasonable goal would be to develop a method for routine use having an MDL of 1 μg/L or lower. Details of our efforts in this regard are included in the Technical Summary below. We do not have similar concerns about copper (Cu) and antimony (Sb). AA methods are much more sensitive for Cu and the action level is much higher (1.3 mg/L). AA methods are not particularly sensitive for Sb and the MCL is low (6 μg/L); but we plan to analyze only selected samples for Sb using an inductively coupled plasma (ICP) method having an MDL of about 0.5 μg/L.
A variety of materials could potentially be used to line or coat LSLs. We decided to focus first on epoxy coatings, then on PET liners, and later on other materials (e.g., HDPE and polyurethanes). Epoxy coatings can potentially leach bisphenol-A (BPA), or other bisphenol compounds substituted for BPA, into the water, and these compounds may in turn react with free or combined chlorine to produce chlorinated by-products. Therefore, our initial efforts to develop methods for organic contaminants associated with lining and coating materials focused on BPA and other bisphenols, and on their chlorine degradation products. We then used these methods to analyze samples from preliminary laboratory experiments examining chlorination of bisphenols at selected pH values. The results of both the analytical efforts and the laboratory experiments are described in more detail below in the Technical Summary.
Assessment of Actual Versus Planned Progress for Each Task
A copy of the previously revised schedule for accomplishing these tasks is attached. Work on Tasks 1, 2, 3, and 6 is underway, and methods and protocols are being developed for Tasks 2, 3, and 4, as described above in the technical summary below. Overall, the project is approximately on schedule and progress to date is reasonably consistent with the project implementation schedule. We had initially hoped to be analyzing field samples and to have begun laboratory experiments involving lined or coated LSL specimens by this time, and we expect to do so in the coming quarter.
In the next reporting period, the research team plans to continue gathering information from utilities, regulators, vendors, and others (Task 1); to continue efforts to obtain monitoring data and water samples from utilities that have installed LSL linings or coatings (Task 2); to complete development of the sampling and analytical protocols needed for the samples obtained from utilities and for the laboratory and demonstration experiments (Tasks 2, 3 and 4); to begin laboratory experiments involving lined and coated LSL pipe specimens; and to continue evaluating the information obtained (Task 6). Now that we have a working method for BPA and related compounds, our next priority is to develop a method for phthalates, which can potentially leach out of PET linings, and to confirm the MDL of the method we plan to use to determine antimony.