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Date: Thursday, December 17, 2015 10:19:54 AM Christine, | think this issue needs to be discussed and decided at the Senior Management Team Level. We are not toxicologists in ODWMA and we rely upon EPA and those of you in the department that have this expertise to provide guidance. It has been our position that there is no safe level of lead exposure, so setting a cleanup criteria based on minimizing the potential for exposure to the extent possible is appropriate. However, with a drinking water standard that is NOT a Maximum Contaminant Level (MCL) but essentially a Treatment Technique that utilizes a statistical analysis of lead results from a sampling pool of targeted, high risk customers and requires that no more than 10% of these results exceed 15 parts per billion will be even more difficult to message should a cleanup criterion be established much lower than this Action Level. Your proposed Part 201 drinking water criterion of 1 ppb may be appropriate. If so, we (DEQ) will just have to develop the proper messaging to explain the difference between drinking water standards, especially Action Levels and Treatment Techniques, and cleanup criteria. Thus far, it has been difficult for the public to comprehend that 15 ppb is not a MCL. Richard Richard Benzie, P.E., Chief Field Operations Section Office of Drinking Water and Municipal Assistance, MDEQ 517-284-6512

We have updated the residential lead direct contact criterion to 200 ppm in soil. This is a draft value which is subject to change. The criterion is generated by the EPA Lead Biokinetic Uptake Model which considers exposure via drinking water, soil, ambient air, and diet. The associated drinking water concentration is 1 ppb. Does the use of a Part 201 drinking water criterion of 1 ppb present you with any heart burn? Thanks for your input! Christine Flage Toxicology Unit Manager Remediation and Redevelopment Division Department of Environmental Quality P.O. Box 30426 Lansing, MI 48909-7926 Phone #: 517-284-5098 [email protected] xxxEND_PAGE:deq02_b297_3502_3502_1

Date: Wednesday, December 16, 2015 5:18:09 PM We have updated the residential lead direct contact criterion to 200 ppm in soil. This is a draft value which is subject to change. The criterion is generated by the EPA Lead Biokinetic Uptake Model which considers exposure via drinking water, soil, ambient air, and diet. The associated drinking water concentration is 1 ppb. Does the use of a Part 201 drinking water criterion of 1 ppb present you with any heart burn? Thanks for your input! Christine Flage Toxicology Unit Manager Remediation and Redevelopment Division Department of Environmental Quality P.O. Box 30426 Lansing, MI 48909-7926 Phone #: 517-284-5098 [email protected] xxxEND_PAGE:deq02_b054_2116_2116_1