«Prepared for MAWSS PWSID: AL0001005 May 2016 CH2M HILL Engineers, Inc. 25 W. Cedar Street Suite 560 Pensacola, FL 32502 Contents Section Page ...»
Lead and Copper Monitoring Plan
CH2M HILL Engineers, Inc.
25 W. Cedar Street Suite 560
Pensacola, FL 32502
Acronyms and Abbreviations
1.1 System Information
1.2 Water Quality Parameters
2.1 Sampling Sites
2.2 Sampling Procedures
Action Level Exceedance Protocol
3.1 Public Education Procedures
3.2 Follow-up Monitoring Procedures
3.3 Corrosion Control Plan Modifications
3.4 Public Notifications
3.5 Customer Notifications
4.1 Distribution System
4.2 Service Laterals
4.3 Private Plumbing Materials
4.4 Water Meters
4.5 Future Material Inventory Program
Appendixes A Chain of Custody B Sampling Protocol C Customer Sampling Results Notification D Lead Violation Notification E Copper Violation Notification Tables 1-1. System Contact Information 1-2. Water System Information 1-3. Laboratory Information 1-4. Water Quality Parameters 2-1. 2015 Sampling Sites 4-1. Water System Materials Inventory 4-2. Water Meter Inventory 4-3. Job Codes for Inventory Identification
Introduction This Lead and Copper Monitoring Plan has been prepared in accordance with the guidelines and regulatory requirements established by the Alabama Department of Environmental Management (ADEM) and includes the following topics:
Monitoring Requirements and Sites Sample Collection Protocol Consumer Notification Violation Notification Requirements Materials Inventory The information compiled in this report is acquired from MAWSS staff’s knowledge of the water system and historical data.
1.1 System Information The Mobile Area Water and Sewer System (MAWSS) owns and operates the water treatment and distribution systems throughout the City of Mobile, Alabama and some surrounding areas in Mobile County. Wholesale water is provided to the City of Prichard and Spanish Fort. The water system is supplied by the J.B. Converse Reservoir located in the western portion of Mobile County. A maximum capacity of 60 million gallons per day (MGD) and 30-MGD are conveyed from the reservoir to the E.M.
Stickney Water Treatment Plant (WTP) and H.E. Myers WTP, respectively. MAWSS also purchases potable water from the Saraland Water and Sewer Board and sells it to the University of Mobile and nearby areas known as College Woods.
Table 1-1 provides information for contacting MAWSS. Table 1-2 provides general water system information and Table 1.3 provides contact information for the two private laboratories used by MAWSS for lead and copper analytical testing.
1.2 Water Quality Parameters The water system is operated to provide a consistent and non-corrosive water to reduce lead and copper leaching. Table 1-4 provides the target water quality parameters. The lead and copper values are dictated by the U.S. Environmental Protection Agency (EPA) and are considered Action Levels (AL). The corrosion inhibitor, poly-orthophosphate, is supplied by Carus Chemical Corporation. The targeted dosing concentration is adjusted based on quarterly monitoring reports performed by MAWSS. During the quarterly monitoring, MAWSS collects samples from eight (8) different sites within the distribution system and at both water treatment plants in addition to exchange the test coupons located at these sites as well. MAWSS monitors pH, calcium (as CaCO3), alkalinity (as CaCO3), total dissolved solids, hardness (as CaCO3) iron, manganese, copper, lead, magnesium, conductivity, chloride, sulfate, orthophosphate, polyphosphate, and total phosphorus.
2.1 Sampling Sites MAWSS is required, based on its classification as a large water system, to collect a minimum of 50 samples annually; however, additional samples typically are collected to provide a broader analysis area to ensure at least 50 samples are analyzed. These samples are collected from the distribution system between June 1st and September 30th for both lead and copper analysis.
MAWSS has a comprehensive list of more than 250 residences that can be used as sampling sites and therefore have no issues with meeting the required number of samples. ADEM Administrative Code r.335-7-11.07 identifies Tier 1 sites as include single family structures containing lead pipe or plumbing, are served by a lead service line, or contain copper pipes with lead solder and were constructed after
1982. Lead services, including lead tubing from the main to the water meter, have never been encountered in the MAWSS distribution system and are believed to not exist therein. However, based on the age of the homes and the expectation that the homes were plumbed with copper and lead based solder, all of the sampling sites in MAWSS’ residence list are identified as Tier 1 sites. The last set of samples were collected between June 24 and July 10, 2015 from the list of sampling sites identified in Table 2-1. The next repeat monitoring samples will be collected between June 1 and September 30, 2016.
MAWSS submits all samples analyzed for lead and copper to ADEM, including those exceeding the 50 required, and are included in the 90 percentile calculation identified in the Lead and Copper Rule.
* = Actual date of construction unknown so used estimated date based on nearby houses
2.2 Sampling Procedures MAWSS typically schedules annual lead and copper sampling in June of each year. Correspondence with the homeowners is the first step to identify which residences will be sampled for a given year. Once a residence is identified, sampling dates will be coordinated for sample kit delivery and pickup by MAWSS personnel. Sample kits will be delivered to the homeowner along with the Sampling Protocol and the Chain of Custody form, which is to be completed by the homeowner.
The Chain of Custody Form can be found in Appendix A and the Sampling Protocol Form can be found in Appendix B.
WT0520161134PNS 2-3 SECTION 3 Action Level Exceedance Protocol ADEM Administrative Code r.335-7-11.01 defines an Action Level as the concentration of lead or copper in water which is used to determine compliance with the regulations; or the 90th percentile level determined from monitoring water at specific sites in the distribution system. MAWSS has never had an Action Level exceedance; however, if MAWSS has exceedance on either lead or copper, the procedures outlined in this section would be followed.
3.1 Public Education Procedures MAWSS will post the information below on their website for the public to access whenever an Action Level exceedance has occurred and will remain on the website until the Action Level is no longer exceeded. This information is also provided in the MAWSS annual Water Quality Report.
Important Health Information about Lead and Copper Potable drinking water rarely contains appreciable concentrations of metals such as lead or copper.
Water chemistry, however, can contribute to the corrosion of distribution piping and household plumbing materials, resulting in the release of metals such as copper, iron, lead, and manganese into drinking water as it is delivered to the customer’s tap.
If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. MAWSS is responsible for providing high quality drinking water but cannot control the variety of materials used in plumbing components. When your water has been stagnant in the plumbing for several hours you can minimize the potential for lead exposure by running or flowing your tap for 30 seconds to 2 minutes before using water for drinking or cooking.
Utilities, such as the Mobile Area Water and Sewer System must ensure that drinking water from the customer's tap does not exceed the Action Level for lead in at least 90 percent of the homes sampled (90th percentile value). Under the authority of the Safe Drinking Water Act, the Environmental Protection Agency (EPA) set the Action Level for lead in drinking water at 0.015 milligrams per liter (mg/L) and the Action Level for copper at 1.3 mg/L. Because lead may pose serious health risks, EPA also set a Maximum Contaminant Level Goal (MCLG) for lead of zero. The MCLG is the level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety. The Action Level is the concentration which, if exceeded, triggers further treatment or other requirements that a water treatment and distribution system must follow.
Corrosive water can cause lead to leach from any piping or plumbing materials that already contain lead.
Therefore, near the final stages of the water treatment process, at both the E.M. Stickney and H.E. Myers Water Treatment Plants, a small dosage (approximately 1 mg/L) of a chemical known as polyorthophosphate is fed into the water for the purpose of preventing corrosion in the distribution system and household plumbing.
MAWSS collects and analyzes for lead and copper at various sites around the city every year as required by the Alabama Department of Environmental Management (ADEM) per the approved Lead and Copper Monitoring Plan. If you are concerned about lead in your water, you may wish to have it tested.
Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline (800-426-4791) or at http://www.epa.gov/safewater/lead.
SECTION 3 – ACTION LEVEL EXCEEDANCE PROTOCOL
3.2 Follow-up Monitoring Procedures Upon exceeding a lead or copper Action Level, MAWSS will increase monitoring consistent with the initial monitoring compliance requirements. ADEM Administrative Code r.335-7-77.05 requires samples to be collected from the initial sites and monitoring must take place during 6-month compliance cycles (January to June or July to December) until compliance is achieved. Monitoring will begin with the next available compliance cycle after the exceedance occurred.
3.3 Corrosion Control Plan Modifications MAWSS has optimized corrosion control and will notify ADEM in writing pursuant of any change in treatment or the addition of a new water source. Any new source or long-term change in water treatment will have written approval from ADEM before being placed into service or being implemented. In addition, an exceedance of the lead and copper AL will also be cause for a review of the water quality parameters and thus the corrosion control plan. The system may be required to conduct additional monitoring or to take other action to ensure the system minimizes the levels of corrosion in the distribution system.
3.5 Customer Notifications All customers for whom lead and copper samples were tested will be notified within 30 days of receipt of the results by MAWSS of the sample test results. The notice to the customer will be mailed or provided by an alternate method approved by ADEM. A sample notification letter for samples that do not exceed the ALs is provided in Appendix C.
In the event the sample results exceed the AL, then an exceedance notification will be provided to the customer. Appendix D provides the notification letter for lead violations and Appendix E provides the notification letter for copper violations.
WT0520161134PNS 3-3 SECTION 4 Materials Inventory
4.1 Distribution System Development of the water distribution system in Mobile, Alabama, began in 1830. At the time, the City of Mobile used hollowed pine logs and cast iron pipe to construct the first portions of the water distribution system. By means of various private entities franchised with the City, the distribution system grew over time. The constructed distribution systems were turned over to the City as the franchisee’s agreements terminated. Although no pine logs are in use for water distribution today, much of the water distribution system is currently constructed of cast iron. As time passed, new main line materials such as ductile iron, PVC and concrete were added to the distribution system. With a few exceptions, cast iron, ductile iron, PVC and concrete are the predominant materials in the distribution system today.
In 1952, an Act of the Alabama Legislature created the Board of Water and Sewer Commissioners of the City of Mobile. The Act transferred ownership of all water and sewer infrastructure from the City to the Board. Record drawings of the distribution system were conveyed to the Board, but they were neither comprehensive nor fully accurate. Many drawings did not reflect main line or service line materials.
Knowledge about the oldest portions of the distribution system is a culmination of information from old drawings (known as linens) and materials encountered as repair crews fixed leaks and replaced pipe over the decades.
In 2002, the Board created a Geographic Information System (GIS) of the water distribution system main lines. The GIS was developed by converting linens, recent record drawings, field crew foreman reports and performing Global Positioning System (GPS) surveys of hydrants and valves. Where some materials were not specifically identified in documents, they were called out in the GIS as cast iron due to both the age of the distribution system in a given area and the fact that cast iron is the material most encountered by water repair crews over the decades. Water main materials classified as “Unknown” are in areas where the certainty of cast iron pipe is diminished because of ductile iron, PVC and concrete transmission lines used in later years.
Understanding pipe materials throughout the distribution system is a key component to developing and operating a corrosion control treatment plan. Table 4-1 provides a breakdown of the water main lengths per material as it is currently identified.
HDPE = high density polyethylene PVC = polyvinyl chloride