Sources and Health Effects of Lead and Copper
The most common source of lead and copper in drinking water is corrosion of plumbing materials throughout the water system. Plumbing materials that can be made with lead and copper include pipes, valves, solder, fixtures, and faucets. This includes water system equipment, service lines, and plumbing materials. The federal Lead and Copper Rule governs how public water systems are regulated to control lead and copper and protect public health. It has requirements for sampling water, treating water, and educating the public.
When consumed through drinking water, lead and copper can cause mild to serious health effects. In particular, lead is a neurotoxin and has a Maximum Contaminant Level Goal (MCLG) of zero. Water systems must take specific actions if more than 10% of samples exceed 15ppb lead or 1.3ppm copper (an action level exceedance, described in more detail below). Sources of lead in the environment have been regulated to protect public health including significant reductions in the amount of lead allowed in plumbing and solder. For more information on sources and health effects of lead, please visit the websites below:
- Lead in Drinking Water (Vermont Department of Health)
- Lead (US EPA)
- Basic Information about Lead in Drinking Water (US EPA)
- Use of Lead Free Pipes, Fittings, Fixtures, Solder, and Flux for Drinking Water (US EPA)
Public Water System Sampling Plans and Monitoring Schedules
Public water systems must sample water from locations at highest risk for lead contamination in their distribution system according to a Division-approved Lead and Copper Sampling Plan.
The frequency of sampling and the number of samples required per monitoring period are based on a water system's population served, prior lead and copper results, and compliance history. Some systems are required to sample lead and copper in six-month monitoring periods (usually after a water source or treatment change or after a lead or copper action level exceedance). Systems on reduced monitoring sample every year or once every three years between June 1 and September 30. Starting in 2017, water systems serving connections with varied seasonal use and occupancy that are already on reduced monitoring may apply for approval to sample between February 1 and May 31.
How to Collect Lead and Copper Samples
Lead and copper samples for water system compliance must be "first-draw" samples taken from cold water taps where the water has not been used for at least 6 hours. Taps should be in regular use and must NOT be artificially flushed prior to sampling. Details on sample collection are provided in the directions below for water systems and for water systems to provide to residents or employees collecting samples for the water system. U.S. EPA published a memo in February 2016 reiterating proper sample collection techniques.
Consumer Tap Notice When Lead and Copper Results are Received
Regardless of the results, all water systems are required to notify participants whose individual locations were sampled with their lead results within 30 days of receiving the lab results. The document below has a template to complete based on the results at the specific tap and the overall system and a certification form to return to the Division.
Calculation of the 90th Percentile and Action Level Exceedances
Instead of maximum contaminant levels (MCLs), lead and copper have action levels (ALs) based on the 90th percentile result. A 90th percentile result is determined by ranking the results and determining where 10% of samples are higher. For a system collecting 10 samples, the 90th percentile result is the 2nd highest result. For a system collecting 5 samples, the 90th percentile result is the average of the two highest results. 90th percentile results are calculated separately for lead and copper, and separately in each monitoring period.
Action Level Exceedance
An action level exceedance for either lead or copper requires the whole water system to take certain steps when more than 10% of tap samples are greater than the lead or copper action level, i.e., when the 90th percentile is above the action level:
Lead Action Level: 0.015 milligrams per liter (mg/L) = 15 parts per billion (ppb)
Copper Action Level: 1.3 mg/L (1300 ppb)
Lead Public Education
When there is a lead action level exceedance, the water system must issue lead public education explaining the lead results and about reducing exposure to lead with 24 hours. The template below includes the required language and information to be filled in about the specific water system (e.g., whether you have lead service lines, what water treatment is used) and recent lead results. A lead public education delivery certification form must be completed and returned to the Division within 10 days of issuing the education.
Water Quality Parameter Monitoring and Corrosion Control Treatment
After a lead or copper action level exceedance, the Division will send the water system a letter outlining compliance requirements and deadlines. This will usually include taking additional water quality samples at the entry point to distribution (a check on lead and copper; and for pH, alkalinity, calcium, and others that may affect corrosion). Based on that chemistry data, the water system must submit a corrosion control treatment (CCT) recommendation. We have developed a packet based on 2016 EPA guidance documents to help the water system review their data and narrow down appropriate CCT options.
CCT Recommendation Guidance including CCT Recommendation Form
Further compliance steps and deadlines including installation of CCT or optimization of existing CCT will depend on subsequent lead and copper results.
Following action level exceedances for lead or copper, the water system must collect a standard set of samples for lead and copper every 6 months and is likely to have additional water chemistry monitoring requirements. Failure to complete any of these activities before specified deadlines would result in a violation.
If you have questions about Lead and Copper Rule implementation in Vermont, please contact the Lead and Copper Rule Coordinator at 802-585-4891 or firstname.lastname@example.org