MEMORANDUM

To:		Docket EPA - HQ - OAR - 2016 - 0490

From: 	Karen Marsh, U.S. EPA, OAQPS, Sector Policies and Programs Division

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Subject:	Discussion of Proposed POTW NESHAP with NYC Department of Environmental Protection (NYC-DEP)
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Date: 	January 4, 2017 
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On January 4, 2017, Karen Marsh had a telephone discussion with Wayne Kuang of New York City Department of Environmental Protection (NYC-DEP) to discuss NYC-DEP's comments on the proposed revisions to the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Publicly Owned Treatment Works (POTW). NYC-DEP owns and operates 2 POTW that are subject to the 1999 NESHAP. These include the Coney Island (Group 2) and North River (Group 2) treatment plants. Below is a summary of the topics discussed during the telephone conversation.

Mr. Kuang stated that both POTW conduct annual monitoring and ToxChem emissions modeling as required in their operating permit issued by the DEP. He indicated that the monthly sampling requirement that was proposed would be an additional burden that EPA had not accounted for in the cost estimated for the proposed rule. Mr. Kuang also stated that most of the HAP listed in Table 1 of 40 CFR part 63, subpart DD are only found in concentrations below the detection limit of these pollutants. Mr. Kuang stated there is no technical merit for treating any of these pollutants at such low concentrations. 

Mr. Kuang also indicated that the reason both POTW are subject to the rule is because they have engines that have potential emissions of formaldehyde above 10 tons per year (tpy). These engines utilize digester gas from the digesters onsite for energy and are exempt from emission standards in 40 CFR part 63, subpart ZZZZ. He indicated that it was overly burdensome to require additional standards on wastewater units when the only reason they are subject to the rule is because of their engines that do not actually have any control requirements. Mr. Kuang indicated they are evaluating their operating practices with the engines and could potentially take a permit limit to maintain the formaldehyde emissions below 10 tpy. He asked if taking this limit would remove them from being subject to the POTW NESHAP. EPA indicated they would examine this question in detail to determine how "once in always in" might apply in this situation. EPA further requested that Mr. Kuang include these comments in his formal submission to the docket.
