Oct 19, 2010

EPA Releases Proposed Air Emission Standards

NACWA believes new standards could impact sewage sludge management nationwide

The U.S. Environmental Protection Agency (EPA) proposed standards under Section 129 of the Clean Air Act (CAA) that will impact options local governments have for the management of sewage sludge. In the U.S., nearly one-fifth of all the sewage sludge produced annually is incinerated in sewage sludge incinerators (SSIs). According to the National Assn. of Clean Water Agencies (NACWA), EPA’s proposed new source performance standards could effectively eliminate the construction of new SSIs, and the standards for existing SSIs could force many communities to abandon incineration as early as 2016.

SSIs are comprehensively regulated under Part 503 regulations, developed by EPA under Section 405 of the Clean Water Act (CWA). NACWA has long advocated the EPA position that SSIs should be regulated under Section 112 of the CAA. EPA now has determined, however, that the proposed new standards should be developed under Section 129.

The new standards will require many existing SSIs to install additional pollution control devices at a capital cost of over $200 million and an annual increase in costs of approximately $100 million, according to EPA. The increased costs could lead to utilities to send their sludge to landfills rather than incinerate it. NACWA believes that EPA’s analysis has understated the true costs utilities will incur to enable them to send their sludge to a landfill and has largely overlooked the negative environmental impacts that could result from abandoning incineration in favor of landfilling.

The proposed standards are based on a maximum achievable control technology (MACT) level of performance. The proposed control levels for mercury, however, are based on a higher standard that will cost an estimated $12 million per ton of mercury removed. NACWA believes that EPA has overestimated the contribution of mercury from SSIs. According to NACWA, the proposed rule’s estimate of mercury emissions each year from 218 SSIs is more than three times the estimate EPA provided to Congress in its 1997 Mercury Study Report, which was released prior to many communities taking action to further control mercury levels in their sludge. Additional mercury reductions from current levels could cost over $40 million per ton, and that cost may increase when EPA-mandated controls for dental clinics are fully implemented.