Effective Lead Sampling

While the Lead and Copper Rule (LCR) has helped reduce lead in drinking water over the past 25 years, complying with sampling requirements can certainly be challenging! Even when a water system faithfully follows protocols, results can be inconsistent and/or unreliable. While the conditions in which samples are taken, or procedures used, are often out of the hands of water operators, the results of these tests can have significant consequences for their water systems, not to mention the communities involved. Just ask the residents of Flint, Michigan. 

Last year, in response to these concerns, the EPA released this memo to clarify tap sampling procedures. In addition, in a move towards a rule revision due out soon, the EPA has also recently issued a LCR Revisions White Paper that offers suggestions on how to improve the rule as well as considerations for improving tap sampling. 

In this white paper, the NDWAC Lead and Copper Rule Working Group corroborates what operators have been saying all along:  the LCR sample site selection and sampling process "provides opportunity for error, particularly given that samples are collected by residents themselves."  In addition, the group says the current system provides "opportunities for systems to implement sampling procedures to avoid exceeding the action level..." 

How to fix the problem? The group suggests substituting a voluntary customer-initiated sampling program for the current LCR tap sampling requirements and/or partnering with technology developers to identify and develop real-time monitoring technologies (such as this inexpensive lead monitor), among other things.

All this is well and good, but until this technology becomes available, and/or a more prescriptive sampling guidance or revised rule released, what is a water operator to do? Is there any sampling method that offers the most reliable results in the most efficient way?

This is the topic of a recent AWWA/WRF study entitled “Evaluation of Lead Sampling Strategies”. The study found that the answer to this question does not come easily. In fact, according to the study, "no sampling method was particularly proficient at finding the peak lead level compared to doing a full profile for each sampling event”. In addition, the type of lead found in samples was inconsistent: “even at a specific site, on some occasions the sampling can be particulate dominated and on other dates the lead can be dissolved dominated or some combination,” the report states.

It is no wonder that water operators across the country may welcome further guidance on this rule. In the meantime, Michigan's DEQ offers a couple of helpful resources: these sampling instructions can help water systems assure residents are following proper procedure and this sample site selection criteria factsheet can help systems ensure a large and diverse enough sampling pool. Please note that the use of guidance material from EPA, other states, and third-parties can offer insight and clarification, but should not be considered a substitute for policies and guidance from your primacy agency. 

To get an update on lead issues in the water industry, join this webinar that will be presented by the VA-AWWA in November. 

Finally, be sure to check out this AWWA video featured on our blog earlier this year: Lead and Copper Sampling.