United States Environmental Protection Office of Water EPA 812-F-95-002 Agency 4604 September 1995 &EPA FACT SHEET UPDATE ON LEAD LEACHING FROM SUBMERSIBLE WELL PUMPS AND PRIVATE DRINKING WATER SYSTEMS Introduction and Summary This fact sheet updates information on potential lead leaching from submersible pumps used in drinking water wells. In the spring of 1994, the Environmental Protection Agency (EPA) issued a fact sheet about the potential hazards associated with lead from submersible well pumps. THIS FACT SHEET REPLACES THE 1994 DOCUMENT. This fact sheet also supplements EPA's 1993 booklet "Lead in Your Drinking Water" (EPA/810-F-93-001) which addresses sources of lead in household plumbing (e.g., faucets and pipes), irrespective of whether the water source is a public water system or a private well. Based on new information, EPA concludes that while some submersible water pumps that contain lead materials may leach lead at levels of concern when the pumps are brand new, lead leaching tends to decrease relatively quickly, arriving at low lead concentrations that in most cases would not pose health risks. Also, U.S. pump manufacturers have recently changed the materials used in their pumps to reduce or eliminate the use of lead. However, because (1) pumps are constructed differently, (2) water corrosivity around the country differs substantially, and (3) other components of a household water system, including plumbing fixtures, may contain lead, the only way to be sure that you do not have elevated lead levels at the tap is to have your water tested. Information presented below explains when testing is appropriate and how to conduct and evaluate tests for lead in your drinking water. New Information The 1994 fact sheet was based on lead leaching data, provided to EPA, collected over a 30- day period from new submersible water well pumps under laboratory conditions. While lead concentrations were high in the water that sat in contact with the pump in the laboratory, EPA noted that it did not have data to tell us how long lead levels would remain elevated or how much of the lead coming from pumps would appear at the water tap and expose residents under "real world" conditions. Since then, EPA, as well as some States, sponsored or conducted field tests that better approximated actual operating conditions. The new field test data provide a better indication of the extent to which lead leaches from new pumps, an estimate of how long lead leaching continues after installation of a new pump, and how much lead may appear at the tap. In two studies, a limited number of new submersible well pumps previously tested in the laboratory were installed in separate, newly drilled wells, in accordance with standard procedures. The new pumps were operated to approximate typical residential usage over four to six weeks. The only components of the test systems that contained leaded brass or bronze components were the pumps, and the samples were collected to isolate lead contributions from the pump as opposed to other components of the water supply system (i.e., valves, solder, faucets). ------- The highest lead concentrations were measured after the water sat in the pumps overnight. All concentrations measured under the real world conditions of these studies were substantially lower than the laboratory testing conducted earlier. In some cases during the first 10 days of the pumps' operation, concentrations at the tap approached or exceeded EPA's "action level" of 15 parts per billion (ppb)1. In general, however, lead leaching from the new pumps declined substantially with time, so that after about four-six weeks of operation, lead concentrations leveled out below 5 ppb at the tap. Changes in Pump Manufacturing U.S. pump manufacturers have significantly changed the materials used in their pumps to greatly reduce, or eliminate the use of lead2. Until 1995, most submersible water well pumps were manufactured with some brass or bronze parts that used lead as an ingredient. Most of these pumps are now made either with brass alloys that contain no lead, or with lead-free materials such as stainless steel or plastic. While EPA has not tested these pumps, we would expect submersible pumps manufactured in the U.S. after January 1, 1995 to leach very low levels of lead, if any. Consult with the manufacturers about any tests that it has conducted that would support low-lead claims for any particular model of pump. What Should You Do? In homes with a new pump or new brass plumbing components, the easiest way in most cases to avoid elevated lead levels in drinking water is to let the water run before using it for drinking or cooking. The longer water resides in your home's plumbing, the more lead it may contain; letting the water run, or flushing the tap usually reduces the lead concentration significantly. Flushing the tap means running the cold water for 15 seconds (if you have a new brass faucet) to 2 minutes or more (if you have a new brass pump or pump fitting that contains lead). This should be done for at least the first four weeks after the pump or other plumbing component is installed. Rather than waste the "first flush" water, you can use it to wash the dishes or water the plants. Showering or toilet flushing can help flush out a new pump, but not a new faucet. While new pumps made in the U.S. now appear to be effectively lead-free, some others may be of concern including older models containing leaded brass that remain in inventory, or new imported models with leaded brass. In addition, other components of a water system such as pipes, fittings, foot valves and check valves, pitless adapters, solder, and faucets may contain lead. Although recent field tests of some older style leaded brass pumps indicate that they themselves are not likely to pose a significant health risk after they have been in use for a relatively short time, they may add some lead to that which may already be leaching from other sources in the household plumbing. Any time a plumbing system component including a pump has to be replaced, homeowners who want to reduce lead exposures as much as possible should consider using products free of brass or bronze that contain lead. 1 Action level is defined in EPA's National Drinking Water Regulations for lead as the concentration above which public water systems are required to install corrosion control treatment and deliver educational materials to the public. 2 August 23, 1994 letter from Robin Grover of the firm Keck, Mahin & Gate, representing the Water Systems Council, to Peter Cook of EPA's Office of Ground Water and Drinking Water. ------- In addition, some water qualities, especially those of neutral or acidic pH, can cause lead to leach from pumps at higher levels for some period of time. Homeowners with these conditions and lead-containing materials in the plumbing system, those concerned about lead exposure (especially with young children), or those who want to know the effect of their flushing routines, should consider having their drinking water tested. Select a certified laboratory in your area and be sure to follow the sampling protocol given below. EPA's Safe Drinking Water Hotline (800-426-4791) can provide you with the name and phone number of the lab certification officer in your State. They, in turn, can provide a list of State-certified labs. Sampling Protocol Household water systems that rely on individual wells may have one of several different designs. Most systems include a storage tank, where water is held before it is distributed through the house. Because lead in your drinking water may also come from lead solder and brass faucets and fittings in the interior plumbing, it is important to determine possible contributions of lead from indoor plumbing components. Checking for lead from both a pump and from indoor plumbing components can be accomplished by sampling your drinking water at two times in a given day and having the water analyzed by a certified laboratory using approved analytical techniques. First, collect a 250 mL (one fourth of a liter, or about 8.5 ounces) sample from the kitchen or bathroom faucet. The certified lab should provide you with a container to collect the sample. This sample should be collected after the water has sat motionless for several hours (e.g., first thing in the morning or after returning from work) without allowing the water to run first. This is called a "first draw sample" and should provide an indication of lead being leached from interior plumbing. Second, to determine the lead concentration that you may be exposed to from that part of your water system that contains the pump, storage tank, associated pipes and valves, and outside faucets, a 250 mL sample should be collected mid-morning after routine water use (showering, flushing, etc.) either: (1) at the outlet of the storage tank, if feasible, after allowing the water to run for 30 seconds, or (2) at a tap after letting the water run for 2 minutes. This is called a "flushed sample". Evaluating Your Test Results If the lead concentration in either sample is more than EPA's action level of 15 ppb (also expressed as 0.015 mg/L), there are several steps you can take. One option is to repeat the test to verify the results. Having a repeat test for comparison can be more informative than having a single test result. If either the first draw or flushed sample test is above 15 ppb, you may consider the following. If you have a submersible well pump that contains leaded brass or bronze and the flushed sample has a lead level above 15 ppb, the source of lead could either be the pump or the plumbing component associated with the pump. If it is a new pump, perhaps the easiest and most economical step would be to operate the pump for several weeks until a follow-up sampling indicates a level below 15 ppb. As the pump ages, lead levels should drop considerably. During this time, bottled water could be used for drinking. If lead levels remain elevated, or if it is an older pump and lead levels are elevated upon initial and follow-up testing, other options should be pursued. Examples include, installing a home water treatment ------- problem component(s), with one that does not contain or leach significant amounts of lead. All lead reduction claims by salespersons or manufacturers of home treatment devices should be investigated. Information on certified treatment units and low lead or lead free pumps can be obtained from NSF, International, or the Water Systems Council (see below). If the lead level is above 15 ppb in the first-draw 250 mL sample, but not in the flushed sample, the lead is likely coming from components of your household plumbing (e.g., lead pipes, solder, or leaded brass faucets). If this is the case, any time the water in a particular faucet has not been used for several hours, flush your cold water pipes by running the water. This could take as few as five to thirty seconds after heavy use such as showering or toilet flushing. For More Information For more information about lead in drinking water, contact the EPA Safe Drinking Water Hotline at 800-426-4791, or via E-mail to Hotline-SDWA@EPAMail.epa.gov, or the National Lead Information Center at 800-424-LEAD. For more information about home treatment units, or low- lead or lead-free submersible pumps, contact NSF International at (800) NSF-MARK, or the Water Quality Association at (708) 505-0161, ext. 270, or the Water Systems Council at (708) 790-3095. ------- |