### NACWA Letter to M. Hale June 2, 2009 Page 1

EXECUTIVE COMMITTEE

PRESIDENT

Marian A. Orfeo Director of Planning

& Coordination

Massachusetts Water Resources Authority

Boston, MA

VICE PRESIDENT

Kevin L. Shafer

Executive Director Milwaukee Metropol itan
Sewerage District
Milwaukee, WI

TREASURER Jeff Theerman

Executive Director Metropolitan St. Louis

Sewer District

Saint Louis, MO

SECRETARY

David R. Williams
Director of Wastewater East Bay Municipal Utility District
Oakland, CA

PAST PRESIDENT

Ch ristopher M. Westhoff
Assistant City Attorney

Public Works General Counsel City of Los Angeles Los Angeles, CA

EXECUTIVE DIRECTOR

Ken Kirk June 2, 2009

Matt Hale Director, Office of Resource Conservation and Recov ery U.S. Environmental Protection Agency, Ariel Rios Bu ilding 1200 Pennsylvania Avenue, N. W. Mail Code: Mail Code: 5301P Washington, DC 20460 Via Electronic Mail: hale.matt@epa.gov

Dear Matt,

Thank you again for taking time to meet with NACWA to discuss your office’s efforts to develop a definition of solid waste for Clean Ai r Act regulatory purposes. As we outlined during the meeting and in our February 2 c omments, we believe the regulatory status of sewage sludge (biosolids) is c lear – it is expressly exempted by the RCRA statutory definition of solid waste as ‘solid and dissolved materials in domestic sewage.’ Congress considered the potentia l overlap in authority over biosolids and chose to comprehensively regulate bio solids under the Clean Water Act. EPA’s many rulemakings regarding the definiti on of solid waste have consistently recognized this Congressional mandate.

NACWA understands that the EPA Office of Air and Ra diation is developing regulations for solid waste incineration units unde r Section 129 of the Clean Air Act. By clarifying that sewage sludge is excluded from t he definition of “solid waste” by the domestic sewage exclusion, EPA is acknowledging that it must regulate sewage sludge incinerators (SSIs) under Section 112 instea d of Section 129. This will help

ensure that incineration remains one of the five av ailable options for biosolids

management.

For many years, NACWA has been supporting EPA’s eff orts to develop SSI regulations under Section 112 of the Clean Air Act. NACWA helped EPA update its database so that it included the significant emissi on reductions achieved by the Part 503 regulations of SSIs under the Clean Water Act. We have attached a description of the data provided by NACWA in response to EPA’s ini tial estimates of the SSI contribution of certain compounds in urban areas re gulated under Section 112(k). It is our understanding that these corrections and upd ates resulted in EPA concluding that SSIs were not major sources of hazardous air p ollutants and that they provided a far smaller percent contribution than originally es timated by EPA.

### NACWA Letter to M. Hale June 2, 2009 Page 2

As area sources regulated under Section 112(k) of t he Clean Air Act, NACWA members can be allies in EP A’s

effort to address risks in urban areas. NACWA memb ers have unique authorities under the Clean Water A ct to regulate the discharges of non-domestic users of th e sewer system. POTW indirect discharge permits ca n be used to reduce the concentration of compounds of co ncern in the sewage sludge and reduce the amount of these compounds that may be emitted into the urban environment. On the other hand, the unpredictable nature of the domestic sewage contribution would ma ke it virtually impossible for a POTW to simultaneo usly

meet all of the established MACT limits for emissio ns regulated under Section 129.

We believe that the best way to ensure SSIs are pro perly regulated under Section 112 is to include in the regulatory definition of solid waste now under deve lopment an express exclusion for domestic sewage an d the sludge generated from the processing of domestic se wage. NACWA believes that the scope of the exclusi on is clear and the existing Part 503 regulations supplem ented with targeted reductions under Section 112(k) provide a sound basis for comprehensive biosolids regulatio n.

Again, thank you and your staff for meeting with us . Please do not hesitate to contact me if you need additional

information about SSIs or would like to discuss the issue further.

Sincerely,

Chris Hornback Senior Director, Regulatory Affairs

ATTACHMENT

cc: Robert Dominak, Northeast Ohio Regional Sewer District Robert Wayland, USEPA Rick Stevens, USEPA