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EXECUTIVE COMMITTEE

PRESIDENT

Kevin L. Shafer

Executive Director

Milwaukee Metropolitan

Sewerage District

Milwaukee, WI

VICE PRESIDENT Jeff Theerman

Executive Director

Metropolitan St. Louis

Sewer District

Saint Louis, MO

TREASURER

David R. Williams

Director of Wastewater

East Bay Municipal

Utility District

Oakland, CA

SECRETARY

Suzanne E. Goss

Government Relations Specialist

JEA (Electric, Water & Sewer)

Jacksonville, FL

PAST PRESIDENT

Marian A. Orfeo

Director of Planning

& Coordination

Massachusetts Water

Resources Authority

Boston, MA

EXECUTIVE DIRECTOR

Ken Kirk September 9, 2009

Assistant Administrator Peter Silva

U.S. EPA Office of Water Ariel Rios Building 1200 Pennsylvania Ave., NW (4101M) Washington, DC 20460

Assistant Administrator Gina McCarthy

U.S. EPA Office of Air and Radiation Ariel Rios Building 1200 Pennsylvania Avenue, N. W. (6101A) Washington, DC 20460

Assistant Administrator Mathy Stanislaus U.S. EPA Office of Solid Waste and Emergency Respon se Ariel Rios Building 1200 Pennsylvania Avenue, N. W. (5101T) Washington, DC 20460

Dear Assistant Administrators:

The National Association of Clean Water Agencies (N ACWA) 1 and its members would like to express their serious concerns with t he U.S. Environmental Protection Agency’s (EPA or Agency) current rulemaking efforts regarding its voluntary

remand of the Commercial and Industrial Solid Waste Incineration (“CISWI”) Unit Rule following the challenge to the rule in Sierra Club v. EPA (No. 01-1048, D.C. Cir).

NACWA also has serious concerns with the parallel E PA effort to develop a

definition of solid waste under Subtitle D of the R esource Conservation and Recovery Act (RCRA) (EPA-HQ-RCRA-2008-0329) as part of the Agency’s response

1 NACWA is the leading representative of over 300 pu blicly owned wastewater treatment agencies across the nation. NACWA’s membership collectively treats and reclaims over 18 billion gallons of wastewater per day and, while our membership includ es utilities of all sizes, we represent the vast majority of major metropolitan agencies across the country. As leading environmental stewards, NACWA members work to ensure that the significant w ater quality improvements made in the 37 years since the Clean Water Act was passed continue and are not reversed.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 2 of 18 September 9, 2009

to Natural Resources Defense Council v. Environmental Protection Agency , 489 F.3d 1250 (D.C. Cir. 2007) [hereinafter

NRDC ] (vacating EPA’s definitions of “commercial or ind ustrial solid waste incineration unit” and “commerc ial or industrial waste”).

EPA has informed NACWA that, as part of these rulem aking efforts, it is considering defining solid was te under RCRA Subtitle D to include municipal sewage s ludge (biosolids). NACWA believes this approach is inconsistent with EPA’s charge under the Clean Air Act (CAA) provisions at issue and is very concerned about the negative and unintended impacts such an action would have on the lawful management of sewage sludg e, including beneficial reuse via land application, su rface disposal and incineration, which together acc ount for the proper management of sludge.

As discussed further in this letter, NACWA urges EP A to consider a different approach that will satisf y the relevant CAA mandates while not disrupting long-sta nding management programs for municipal sewage sludge. NACWA requests a meeting with you and the relevant Agency staff to discuss this issue further

.

NACWA believes that EPA’s prior determination that sewage sludge incinerators (SSIs) are not subject t o regulation as solid waste incineration units (SWIUs ) pursuant to § 129 of the CAA is consistent with t he plain language of the statute. In particular, publicly o wned treatment works, including SSIs, are explicitl y regulated under CAA § 112, and therefore cannot be regulated under CAA § 129. Furthermore, NACWA is concerned t hat EPA’s current rulemaking efforts to respond to the narrow CAA-specific NRDC decision will undermine the regulatory harmony that exists among the water, air , and waste programs that together provide comprehe nsive regulation of sewage sludge, including the manageme nt of sewage sludge in SSIs. Defining solid waste to include sewage sludge will create enormous uncertai nty regarding the recycling and disposal programs t hat fully operate in compliance with the 40 CFR Part 50 3 (Use or Disposal of Sewage Sludge) regulation’s c lear mandates that are protective of human health and th e environment.

NACWA urges EPA to:

(1) Maintain its existing regulatory determination that SSIs are not subject to § 129 of the CAA.

(2) Develop a regulatory definition of solid waste that recognizes the Agency’s past interpretations of th e RCRA definition of solid waste, the Clean Water Act (CWA), and the CAA.

These actions will maintain the careful regulatory balance that exists among all of these programs by carving out sewage sludge and its uses from any new Subtitl e D regulatory definition of solid waste when such sludge is regulated under § 405 of the CWA and Part 503 regul ations.

The remainder of this letter provides a detailed di scussion of NACWA’s four key points:

• EPA is precluded from regulating SSIs under CAA § 1 29 because the statute expressly regulates SSIs under the POTW provisions contained in CAA § 112. SSIs are part of POTWs, as defined in CAA § 112. 2 As such, EPA is correct in its longstanding determi nation that SSIs are regulated under CAA § 112, not under CAA § 129, even if EPA reached this conclusio n for different reasons.

2 CAA § 112 incorporates by reference the CWA defini tion of “treatment works.”

### NACWA Letter to EPA on Sewage Sludge Incineration Page 3 of 18 September 9, 2009

• Regulation of SSIs under CAA § 112 is also consiste nt with the comprehensive program for regulation of POTW sewage sludge that has been in place for ma ny years pursuant to broad CWA and RCRA mandates. These mandates, which predate the 1990 C AA Amendments under which CAA § 129 was added, provide a comprehensive and cohesive regulat ory framework for the safe use and disposal of sewage sludge, including incineration and other ben eficial uses. Regulating SSIs under CAA § 129 would significantly alter these longstanding progra ms’ clear distinction between sewage sludge and solid waste and would severely disrupt and undermin e these primary national programs for regulating the use and disposal of sewage sludge. There is no thing in CAA § 129 or its legislative history to su ggest that Congress intended to dismantle or in any way d isrupt the existing framework for sewage sludge management. To the contrary, Congress’ express inc lusion of POTWs, including SSIs, under CAA § 112 signifies a clear intent to provide for any further regulation of air emissions from SSIs under the CA A’s § 112 framework.

• EPA has already properly determined that SSIs are n ot subject to regulation under CAA § 129. The Agency’s determination is the result of more than 1 0 years of notice and comment rulemaking, judicial challenges, and negotiations involving all interest ed parties. Additional public comment submitted during EPA’s prior reconsideration of this issue di d not generate new information that would alter EPA’s analysis. Furthermore, nothing in the NRDC decision warrants a different conclusion, because that case did not evaluate whether SSIs are regulat ed under CAA § 112 or § 129.

• Including sewage sludge in any new Subtitle D defin ition of solid waste would create confusion over past interpretations of the RCRA definition of soli d waste and lead to cascading regulatory consequences that would call into question biosolid s management programs under current federal and state law. This will also undermine the express rig ht that Congress preserved to local communities to make local choices about sewage sludge management. EPA is obligated to uphold the carefully crafted regulation of sewage sludge, including sewage sludg e incineration, which harmonizes the CAA, CWA, and RCRA authorities. Preserving the existing regu latory framework is not merely good policy, it is compelled by Congress under § 112 of the CAA (direc ting that POTWs be regulated under § 112), § 1004 of RCRA (defining solid waste to exclude solid mate rial in domestic sewage), and 405 of the Clean Wate r Act (establishing a comprehensive regulatory framew ork for the solid material in domestic sewage).

NACWA urges EPA to adhere to Congress’ clear intent to provide for the safe use and disposal of sewage sludge, to preserve local control over these management cho ices, to encourage the beneficial use of sewage slu dge, and to preserve incineration as a safe, viable, and cos t-effective management practice for sewage sludge w here applicable, consistent with the clear and longstand ing intent of Congress and EPA. EPA may do so and still fulfill the obligations created by the NRDC decision, by adopting the approach set forth in th is letter.



## I. Congress Regulated Air Emissions From POTWs, I ncluding SSIs, Under CAA § 112, Not Under CAA § 129

Clean Air Act § 112(e)(5) requires EPA to establish emission standards for hazardous air pollutants (H APs) for publicly owned treatment works (POTWs). In particu lar, this provision states:

### NACWA Letter to EPA on Sewage Sludge Incineration Page 4 of 18 September 9, 2009

The Administrator shall promulgate standards pursua nt to subsection (d) of this section applicable to publicly owned treatments works (as d efined in Title II of the Federal Water Pollution Control Act [33 U.S.C.A. § 1281 et seq.]) not later than 5 years after November 15, 1990. 42 U.S.C. § 7412(e)(5).

The definition of “treatment works” contained in th e Clean Water Act is broad and includes “ any devices and systems used in the storage, treatment, recycling and reclamation of municipal sewage . .

. or necessary to recycle or reuse water . . . and an y works... that will be an integral part of the treatment process (including land for the storage of treated wastewater in land treatment systems prior to land application) or is used for ultimate disposal of residues resulting from such treatment. ” 33 U.S.C. § 212(2)(A) (emphasis added). This language clearly encompasses the many areas of a POTW used to manage sewage sludge, including treatment and storage equipment and areas , land areas where sludges are managed, and incinerators that are “used for ultimate disposal o f residues resulting from such treatment.”

Thus, CAA § 112(e)(5) regulates air emissions for H APs from POTWs broadly and without limitation. As such, SSIs operated by POTWs, and other areas of POTWs us ed to generate and manage sludge, are “treatment works” under the CWA, and thus are covered by CAA § 112(e)(5). CAA § 112(n)(3) underscores this concl usion, as it expressly provides authority for EPA to work with POTWs to study and characterize emissions for purposes of regulating these under CAA § 112(e). See also CWA § 405(f)(1) which requires permits for POTWs under § 402 of the CWA to include requirements for the use or disposal of sewage sludge.

EPA has long understood that SSIs are an integral p art of POTWs. For example, under the early CWA Tit le II construction grants program, in which Congress incl uded the “treatment works” definition noted above, EPA approved funding for many SSI construction, upgrade and expansion projects. Indeed, based on informat ion NACWA has collected, many if not all of the 231 SSI s operated by municipalities in the United States w ere constructed or upgraded at some point in time with federal construction grants. This would have been impossible if EPA did not consider SSIs to be part of “treatment works.” EPA’s recognition that sewag e sludge management, including incineration, is an inherent part of POTW operations for which federal funding w as made available, is reflected in the primary regulat ory program for sewage sludge management, the “Part 503”

program, 3 which was developed under the authority of CWA § 405 and RCRA. For example, EPA has stated

that:

Sewage sludge has been an important concern of the Agency since 1972, when EPA, through

the Federal Water Pollution Control Act constructio n grants program, began assisting in the financing of wastewater treatment facilities. 58 Fe d. Reg. 9248, 9260 (Feb. 19, 1993).

Treatment works treating domestic sewage, as noted above, include facilities dedicated to the disposal of sewage sludge (i.e., surface disposal s ites and incinerators). 58 Fed. Reg. 9248, 9359 (Feb. 19, 1993). See also 40 CFR 122.2 in which tre atment works is defined to include sewage sludge treatment systems.

Thus, it is apparent that EPA has long understood, as has Congress, that SSIs are “treatment works” un der the CWA. Congress’ intentional use of this well-unders tood term in CAA § 112 has no other conceivable mea ning.

EPA should, therefore, continue to include SSIs as part of POTW regulation under CAA § 112.

3 40 CFR Part 503, Standards for the Use or Disposal of Sewage Sludge.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 5 of 18 September 9, 2009

The legislative history of CAA § 112 also indicates that Congress intended the air emissions from POTW operations covered by CAA § 112 to include air emis sions from SSIs. For example, Congress indicated that “The Administrator is specifically directed to incl ude publicly owned treatment works (as defined in t he Clean Water Act) and [certain RCRA facilities] among the categories of major sources pursuant to this subsection....The Agency has also indicated that ai r emission standards for POTWs may be promulgated u nder the Clean Water Act. There is no standard of prote ction of either human health or the environment fro m releases to air under that Act. It is more likely that appropriate standards would survive a legal te st, if established pursuant to these new authorities of § 112 of the Clean Air Act.” 4

The CWA-derived air emission standards that CAA § 1 12 was intended to supplement include those that control emissions on SSIs. Thus, Congress was well aware that air emissions from SSIs were already re gulated by the CWA § 405 requirements and chose § 112 as th e means to update these requirements as warranted b y the applicable protection requirements. In addition, P OTWs and SSIs are both included on a list of source categories intended to be regulated under CAA § 112

. 5 By contrast, as NACWA has noted in previous correspondence to EPA, the legislative history of C AA § 129 is silent as to both POTWs and SSIs.

Further demonstrating Congress’ clear direction, EP A has already regulated SSIs as intended under CAA § 112, by identifying SSIs as an area source category unde r CAA § 112. EPA examined the issue of the CAA reg ulation

of SSIs in 1992, when it issued its initial list of major and area source categories under § 112. Tha t initial list included sewage sludge incinerators as a source cat egory. In this notice EPA expressly states “the A gency does not consider sewage sludge incineration units to be covered under § 129 so it has authority to list an d set standards for these units under § 112." See also, 58 Fed. Reg. 9248, 9262, 9276-77 (Feb. 19, 1993) (n oting that SSIs are regulated under § 112 of the CAA). In 19 99, EPA promulgated a NESHAP under § 112 for the treatment plant part of a POTW. 64 Fed. Reg. 57572 (Oct. 26, 1999). Significantly, while the definit ion of POTW treatment plant is appropriately focused on th e treatment part of a POTW, the definition of POTW in that rule is much broader and encompasses everythin g that is eligible to receive grant assistance unde r Title II of the CWA. See, 40 CFR 63.1595. In February 2002 , EPA revised its list of source categories under § 112 to delete SSIs, not because they were not covered by § 112, but because there were no major sources in th at category. 67 Fed. Reg. 6521 (Feb. 12, 2002). EPA retains the authority to regulate SSIs under § 112. For example, in June 2002, after EPA deleted SSIs from the source category list for the development of NES HAPs, EPA added SSIs to the list of area source categorie s under §§ 112(c) and 112(k) of the CAA . 67 Fed. Reg. 43112 (Jun. 26, 2002; 67 Fed. Reg. 70427) (Nov. 22, 2002)

.

CAA § 129(h)(2) states that: “no solid waste incin eration units subject to performance standards unde r [§§ 129 and 111] shall be subject to standards under [§ 112 (d)].” Thus, the language of CAA § 129(h) makes cl ear that EPA’s regulation of sources under CAA § 129 or CAA § 112 is mutually exclusive. EPA has consistently recognized that sources regulated under CAA § 112 c annot also be regulated under CAA § 129. Since are a source categories are subject to the promulgation o f emission standards under CAA § 112(d), SSIs canno t also be regulated under CAA § 129. As the D.C. Circuit exhorted EPA in NRDC , EPA must follow the plain language of the statute. In this case, however, the plain l anguage of the statute directs EPA to regulate POTW s (including SSIs) under § 112. Nothing in § 129 leads to a dif ferent result because it is axiomatic that a specif ic provision of a statute is controlling over a general provision. “However inclusive may be the general language of a statute, it

4 Senate Report No. 100-231, Committee on Environmen t and Public Works, 1990 CAA Legislative History 94 36, 9668.

5 Senate report No. 101-228, Committee on Environmen t and Public Works, 1990 CAA Legislative History 83 38, 8528.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 6 of 18 September 9, 2009

will not be held to apply to a matter specifically dealt with in another part of the same enactment.” Fourco Glass Co. v. Transmirra Products Corp. , 353 U.S. 222, 228 (1957).

The bottom line is that Congress mandated, and EPA must stand by its original and longstanding determination, that POTW SSIs fall under CAA § 112. Indeed, EPA has already adopted regulations based on this conclusion. While EPA can change its mind on policy issues if the Agency develops a reasoned ana lysis to support the change, Motor Vehicle Mfrs. Ass'n. v. State Farm Mutual, 463 U.S. 29 (1983), it cannot act contrary to a statutory directive that compels a singular outcome , as it does here. NRDC does not alter these fundamental principles of statutory construction and, indeed, i s based on an admonition to EPA to apply the CAA as written. Any action seeking to regulate SSIs under CAA § 129 rather than CAA § 112 would be contrary to the sta tute.



## II. CAA § 129 Does Not Apply to SSIs

CAA § 129 applies to solid waste incineration units that combust solid waste. To determine the covera ge of CAA § 129, EPA must look at both components – wheth er a material being combusted is a solid waste and whether the combustion unit is of the type specifie d by Congress. SSIs do not fit under either of the se components. As noted above, SSIs are part of POTWs regulated under CAA § 112 and thus are not include d in the types of combustion units Congress sought to re gulate under CAA § 129. This is clear from the sta tutory language in CAA § 129, as well.

The legislative history of CAA § 129 indicates that SSIs were not intended to be regulated as “solid w aste incineration units.” The provisions now codified i n CAA § 129 originated in a bill entitled “Municipa l Waste Combustion Control Act of 1989,” introduced in Cong ress on January 25, 1989. S. 196, 101st Cong. (198 9). The express purpose of the proposed legislation was to address the “garbage crisis” facing the nation in the late 1980s and to “establish the needed regulatory progr am to make municipal waste incineration an environmentally sound part of our Nation’s waste management.” 6 While subsequent legislative history reveals Cong ress’ concern with other specific types of large incinera tors in addition to municipal waste combustors ( e.g. , medical

waste incinerators and industrial incinerators burn ing waste paper, wood, yard wastes, food wastes, ba tteries and plastics), Congress did not once mention POTW s ewage sludge or SSIs as a type of incineration to b e covered under CAA § 129, or in any way suggest that its concerns over the incineration of municipal so lid waste extended to the incineration of sewage sludge. Thi s silence in the context of CAA § 129 is fully cons istent with the fact that Congress expressly covered POTWs and SSIs in CAA § 112.

The concept EPA is reportedly exploring, which woul d establish a regulatory definition of solid waste under Subtitle D of RCRA that includes sewage sludge, wou ld upset the carefully wrought provisions of CWA § 405, the RCRA definition of solid waste, and the scope o f the Domestic Sewage Exclusion which Congress incl uded

in order to avoid

duplicative RCRA and CWA regulation of POTWs. Bot h Congress and EPA gave comprehensive and careful thought to the proper reg ulation of use and disposal of sewage sludge under CWA and RCRA authorities that were in place long before CAA § 129 was enacted. Nothing in CAA § 129 or i ts legislative history suggests that Congress provided EPA with authority to undo or seriously undermine the comprehensive sludge management programs already in place under these other laws. Moreover, EPA must recognize that these longstanding sewage sludge man agement regulations were not before the NRDC court. Although the court’s admonitions to EPA may superfi cially suggest that the court mandated a broad defi nition

6 Id . (emphasis added).

### NACWA Letter to EPA on Sewage Sludge Incineration Page 7 of 18 September 9, 2009

of solid waste for purposes of CAA § 129, such a re ading simply makes no sense, particularly where it is clear that other types of incineration are covered in oth er Sections of the CAA. EPA has a responsibility t o apply the court’s decision carefully, recognizing both the li mits of CAA § 129 and the mandates of unrelated sta tutes that would be adversely affected by a broad new definiti on of solid waste.

The discussion immediately below addresses the inte rplay between the CAA and RCRA and how it impacts t he applicability of CAA § 129. Part III of this lette r, which follows, addresses the CWA Part 503 regula tions and programs developed under RCRA that provide a compre hensive regulatory framework for the management of sewage sludge. This discussion explains why, in ad dition to the CAA analysis, other laws prohibit EPA from regulating the combustion of sewage sludge as solid waste under CAA § 129.



## A. Sewage Sludge Has Not Been Regulated as Solid Wa ste by EPA or Viewed as Solid Waste by Congress

Sewage sludges generated by POTWs, including those combusted in SSIs, have historically not been viewe d as solid wastes by Congress and (as discussed in the n ext section) generally have not been regulated as s olid wastes by EPA. Therefore, POTW sewage sludge should not b e defined as solid waste for the purposes of the de finition of “solid waste incineration unit” provided in CAA § 129(g)(1). 7 CAA § 129(g)(6) specifically provides that the term “solid waste” is to have the meaning as set fo rth and established under RCRA. 8

RCRA defines “solid waste” as:

Any garbage, refuse, sludge from a waste treatment plant, water supply treatment plant, or air pollution control facility and other discarded mate rial, including solid, liquid, semisolid, or contained gaseous material resulting from industria l, commercial, mining, and agricultural operations, and from community activities, but does not include solid or dissolved material in domestic sewage . . . . RCRA § 1004(27) (emphasis added).

Solid or dissolved material in domestic sewage is e xcluded from this definition – this exception is co mmonly referred to as the “Domestic Sewage Exclusion” unde r RCRA. The Domestic Sewage Exclusion expresses Congress’ clear intent to forego RCRA regulation wh en a material is already regulated under the CWA.

While the legislative history of CAA § 129 is silen t as to the definition of “solid waste” (other than , as discussed below, to make clear that Congress was primarily co ncerned with municipal solid waste), the Domestic Sewage Exclusion had been written into RCRA for 25 years a t the time Congress passed the 1990 CAA Amendments. Accordingly, in incorporating RCRA’s definition of “solid waste” in CAA § 129, Congress was well aware of the Domestic Sewage Exclusion encompassed in the defini tion of “solid waste” and of EPA’s interpretation a nd application of that definition with respect to the regulation of sewage sludge from POTWs.

7 We also acknowledge EPA’s statement in the Agency’ s 2000 regulatory agenda that sewage sludge when combusted in SSIs is a solid waste. 65 Fed. Reg. 23,430, 23,460 (Apr. 24, 2000). That statement, however, was not made in the context of a rulemaking preamble but rather in a semi-annual regulatory agenda and it has not b een subjected to public comment. It also is counte rmanded by numerous statutory and regulatory provisions discussed herein, and is entitled to little weight.

8 CAA § 129(g)(6) (The term “solid waste” shall have the meaning established by the Administrator pursu ant to the Solid Waste Disposal Act.)

### NACWA Letter to EPA on Sewage Sludge Incineration Page 8 of 18 September 9, 2009

Moreover, shortly after Congress passed the 1990 CA A, Congress amended RCRA to expand the scope of the Domestic Sewage Exclusion to cover Federally Owned Treatment Works. At the time of passage of this amendment (and after a year of debate and revision) , Senator Chafee confirmed Congress’ understanding that the Domestic Sewage Exclusion exempts POTW sludge f rom RCRA regulation:

Sewage treatment plants operated by local governmen ts – POTWs – have a special exemption called the domestic sewage exclusion under RCRA. If most of the waste received by a POTW is domestic sewage, their sludge and wastewater is exempt from hazardous industrial waste regulation even if they are also receiving hazardous industrial waste through sewer connections . 138 Cong. Rec. 514755, 514758 (Sept. 23, 1992) (emphasis added).

Accordingly, in using the definition of “solid wast e” under RCRA for purposes of defining the scope of CAA § 129, Congress was aware that POTW sewage sludge wou ld be excluded from the CAA § 129(g) definitions, which, in turn, would preclude regulation of SSIs u nder CAA § 129. Express exemption of SSIs from the

definition of “Solid Waste Incineration Units” under CAA § 129 was therefore unnecessary.

In RCRA rulemakings, EPA has similarly interpreted the scope of the Domestic Sewage Exclusion to inclu de sewage sludge generated by POTWs. The clearest exa mple of this exclusion of POTW sewage sludge from t he definition of “solid waste” under the RCRA regulato ry framework is found in EPA’s promulgation of a ru le to identify and list hazardous wastes for petroleum re finery process wastewaters. In the preamble to the Agency’s 1990 Final Rule, EPA concluded that POTW sewage slu dge falls within the Domestic Sewage Exclusion:

These wastes [P038 and K048 wastes] are being added to the list of [hazardous] wastes . . . in order to regulate sludges generated at wastewater t reatment facilities on site at petroleum refineries as well as sludges generated at off-site wastewater treatment facilities. 9 55 Fed. Reg. 46,354, 46,364 (Nov. 2, 1990) (emphasis added).

Accordingly, both Congress and EPA have consistentl y recognized the possibility of duplicative regulat ion under both the RCRA and CWA programs and have consi stently concluded that POTW sewage sludge should be excluded from regulation under RCRA as a waste. NACWA believes EPA must be consistent and confirm that POTW sewage sludge is not “solid waste” for r egulatory purposes, and incinerators which combust POTW sewage sludge do not qualify as “solid waste incine ration units” under CAA § 129.



## B. EPA Properly Determined that SSIs are Not “Solid Waste Incineration Units” and, Therefore, They are Not Subject to Regulation Under CAA § 129

Section 129 of the CAA requires EPA to develop and adopt new source performance standards and emission s guidelines for “solid waste incineration units.” T he potential scope of incineration units covered by CAA § 129 is expressly limited by the definition of “solid wa ste incineration units.” In CAA § 129(g)(1), Congr ess defined

this term to mean:

9 It should be noted that if wastewaters generated at petroleum refineries are discharged to a POTW an d such wastewaters are mixed with domestic sewage from nonindustrial sources, the sludges generated in the POTW are covered under the domestic sewage exclusion and are not included in today’s listings.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 9 of 18 September 9, 2009

A distinct operating unit of any facility which com busts any solid waste material from any commercial or industrial establishments or the gene ral public (including single and multiple residences, hotels, and motels) . . . . 10 CAA § 129(g)(1).

As fully explained above (and in NACWA’s March 17, 1997 and August 14, 2006 comment letters), biosolids generated by POTWs are not a “solid waste.” Furthe rmore, sewage sludge generated by POTWs are not “fr om commercial or industrial establishments or the gene ral public.” Simply stated, incinerators which com bust sewage sludge from POTWs are not “solid waste incin eration units” and do not fall within the scope of EPA’s duty to regulate pursuant to CAA § 129.

As EPA has previously determined, SSIs are not subj ect to regulation under CAA § 129 because the sludg e combusted by SSIs come from POTWs, not “commercial or industrial establishments or the general public. ” POTWs are not properly characterized as “commercial or industrial establishments” or “the general publ ic.” The fact that the sewered population served by a PO TW is assessed at a monetary rate for the collectio n and treatment services provided by the POTW does not tr ansform it into a “commercial establishment” within the commonly understood meaning of that term, which mus t presumably be the meaning intended by Congress in CAA § 129(g)(1). Moreover, the fact that Congress and NACWA refer to POTWs as “plants” or “facilities ,” or that they refer to their works collectively as an “ industry,” does not transform POTWs into “commercia l or industrial establishments” for purposes of CAA § 12 9. In enacting § 129, Congress was clearly concern ed about municipal solid waste – trash, or garbage – generat ed by households and businesses. It was not at all concerned in § 129 with sewage sludge management, and adoptin g an approach to the CISWI definitions that ignores CAA § 112’s coverage of POTWs and SSIs would be contrar y to statute.

These conclusions about the scope of CAA § 129 are further validated when one considers that Congress explicitly included POTWs under CAA § 112 and prohi bited regulation of sources under both CAA §§ 112 a nd 129. By doing so, Congress purposefully excluded P OTWs, including SSIs, from the types of combustion units intended to be covered by CAA § 129.

In sum, Congress did not intend SSIs to be subject to CAA § 129 regulation. Section 129 applies to cer tain types

of incinerators that combust “solid waste” as defin ed under RCRA, and Congress fully understood the exclusion of sewage sludge from the definition of s olid waste at the time CAA § 129 was enacted. Furt hermore, SSIs burn sewage residues, not solid waste “from co mmercial or industrial establishments or the genera l public.” SSIs do not fall within this definition, and therefore, cannot be regulated under CAA § 129. The plain language of CAA § 129, as further validated by its legislative history, supports no other conclusion.

The holding in NRDC does not alter this analysis. The NRDC decision directs EPA to use RCRA’s definition of solid waste in determining the scope of regulation for covered units under CAA § 129. Since POTWs and SSIs are not covered by CAA § 129, the NRDC decision does not require or authorize EPA to deve lop a definition of solid waste that includes or affects sewage sludge. Therefore, EPA’s response to the NRDC decision should be appropriately narrow, as well, since POTWs and SSIs are explicitly covered under CAA § 112. EPA has

10 The definition of “solid waste incineration unit” excludes: (1) incinerators or other units which are Treatment, Storage and Disposal Facilities (TSDFs) under RCRA; (2) materials recovery facilities which combust waste for the primary purpose of recovering metals; (3) “qualifying small power production facilities” and “qualifying cogeneration facilities” which burn hom ogeneous waste (such as tires or used oil) for the production of electric energy or electric energy and steam or forms of useful energy ; and (4) air curtain incinerators, provided that such incinerators burn only wood wast es, yard wastes, and clean lumber. CAA § 129(g)(1)

.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 10 of 18 September 9, 2009

previously and properly determined that POTWs and S SIs are covered under CAA § 112, and, as such, the review directed by the court in NRDC simply does not apply to SSIs or to sewage sludge.

For all of these reasons, EPA lacks authority to re gulate SSIs under CAA § 129. EPA previously made t his determination and nothing in NRDC supports a different conclusion. Moreover, CAA § 1 12 clearly applies to SSIs, thereby precluding application of CAA § 129 t o SSIs.



## III. Sewage Sludge Management Is Already Comprehe nsively Regulated and Regulation of SSIs Under CAA § 129 Would Conflict with Existing L aws

The current regulatory harmony that exists for sewa ge sludge management is implemented through and supported by the comprehensive program that has bee n carefully developed under CWA § 405 and several k ey provisions and exclusions that exist under the RCRA regulatory framework. The statutory and regulator y provisions that contain and implement the sewage sl udge management program distinguish between sewage sludge and solid waste, and thereby demonstrate tha t they are different types of material. As a resul t, EPA’s reported effort to categorically deem sewage sludge a solid waste for regulatory purposes under RCRA S ubtitle D, for the limited purposes of implementing the req uirements of CAA § 129 (which does not apply to SSI s in any event), is misdirected.

If EPA moves forward with the notion of deeming sew age sludge a solid waste for regulatory purposes un der RCRA Subtitle D, such action will severely conflict with the carefully crafted distinctions made by Co ngress and EPA over many years to provide for proper sewage sl udge management. This action will also place RCRA regulatory responsibilities on POTWs that Congress fully intended would not apply due to strict regula tion of POTWs under the CWA and its NPDES program. In addi tion, such action could severely limit how sewage sludge may be managed, which directly contravenes C ongress’ preservation in the CWA of local control o ver sewage sludge management options.

In short, if EPA erroneously deems sewage sludge a solid waste in an effort to guide its implementatio n of the CAA, it will wreak havoc on well-established progra ms for comprehensive sewage sludge management that Congress deliberately crafted with care under the C WA and RCRA many years before the enactment of CAA § 129 in 1990. NACWA doubts the existence of any s upport in the relevant statutes or legislative hist ories for such an approach, and we are equally confident that Congress had no intention for CAA § 129 to be read in a way that undermines these longstanding programs.

Instead of pursuing the approach EPA is reportedly considering, NACWA respectfully suggests that any n ew definition of solid waste that EPA believes is nece ssary in order to carry out CAA § 129 should be dra fted to include an express regulatory exclusion for sewage sludge that is managed in accordance with other pre -existing regulatory requirements. The discussion below deta ils the reasons why this approach is critical. Sin ce CAA § 129 does not apply to sewage sludge, this approach should also serve EPA’s purposes in implementing th at provision consistent with NRDC and other legal requirements.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 11 of 18 September 9, 2009



## A. Interplay of RCRA and CWA § 405

Congress established the concept of a broad POTW ex emption from the then-nascent federal solid waste l aws as early as 1965. 11 This was an early recognition that a comprehensiv e solid waste program, designed primarily to address hazardous wastes, was not necessary to a pply at POTWs as long as they were effectively regu lated under the CWA, which has always been and remains th e primary statutory authority for comprehensive regulation of POTW operations. The Solid Waste Dis posal Act and RCRA included the Domestic Sewage Exclusion in explicit recognition of this critical policy choice. 12

Indeed, as EPA began its long efforts to define “so lid waste” and “hazardous waste” for purposes of Su btitle C of RCRA, the Agency explicitly understood and discu ssed the importance of the comprehensive federal se wage sludge management program it was beginning to devel op to carry out Congress’ intent and to complement the RCRA rules being developed for solid wastes.

For example, in the 1980 preamble to EPA’s developm ent of the Subtitle C regulations, EPA describes th e importance, scope, and ultimate supremacy of the to -be developed CWA § 405 program, indicating that, o nce this program was in place, it would serve as the co mprehensive regulations for use and disposal of sewage sludge. 45 Fed. Reg. 33,084, 33,102 (May 19, 1980) (“Once such a regulation is in place, sewage sludg e will be exempted from coverage under other sets of regulati ons.”). Thus, there has been a clear recognition f or over 30 years that sewage sludge is different than solid wa ste for regulatory purposes, and that sewage sludge is primarily regulated under the CWA. This recognitio n has not been challenged and stands today.

EPA proposed its CWA § 405 regulations in 1989, and enacted the final rules, known as the Part 503 regulations, in 1993 (40 CFR Part 503). As EPA exp lained at length in the preamble to the proposed ru les, CWA § 405 established requirements for a comprehensive program to develop appropriate regulations for use and disposal of sewage sludge. EPA described the lengt hy and complex process it undertook to develop rigo rous scientific studies to ensure the safe management of sewage sludges whether they were to be used or dis posed. 54 Fed. Reg. 5746, 5764-5791 (Feb. 6, 1989) (descri bing the Agency’s exposure assessment models, human health and environmental criteria, aggregate effects asses sment, and the alternative regulatory approaches th e agency considered when developing the sewage sludge dispos al regulations). EPA also explained the major effo rt undertaken to ensure that the requirements of the C WA and RCRA as well as those in the CAA were consid ered and reconciled in the Part 503 program requirements

. Id. at 5748 (noting that EPA “carefully examined the requirements of other media programs and media-spec ific statutes” in developing the proposed rules and “where possible . . . used the tools and standards developed under these other programs”). NACWA stro ngly urges EPA to be consistent with its past regulatory determinations and do the same in its forthcoming Subtitle

D definition of solid waste.

In its CWA § 405 proposed rulemaking, EPA also desc ribed the relationship of the new Part 503 rules to RCRA regulations in 40 CFR Parts 257 and 258. Part 257, which establishes criteria for what constitutes a sanitary landfill versus an open dump, 44 Fed. Reg. 53,438 ( Sept. 13, 1979), was promulgated under RCRA and the CWA.

See 58 Fed. Reg. at 9261. EPA explained at that time that Part 257 exempted land application of sewage s ludge

11 Solid Waste Disposal Act, Pub. L. 89-272, 79 Stat. 992 (1965).

12 Solid Waste Disposal Act, Pub. L. No. 89-272, § 20 3(4), 79 Stat. 992, 998 (1965) (defining the term “ solid waste” to exclude “solids or dissolved material in domestic sewage or other sign ificant pollutants in water resources . . . .”); accord Resource Conservation and Recovery Act, Pub. L. No. 94-580, § 1004, 90 Stat. 2795, 2801 (1976).

### NACWA Letter to EPA on Sewage Sludge Incineration Page 12 of 18 September 9, 2009

because that activity is not solid waste disposal. Id. Additionally, Parts 258 and 503 together provide d that, as long as disposal of sewage sludge in a municipal so lid waste landfill met the specific requirements of Part 258 for that activity, this would constitute compliance with the Part 503 regulations and CWA § 405. When EPA promulgated the Part 503 final rule in 1993, the Ag ency recognized that the 1990 CAA Amendments might subject SSIs to new requirements in addition to the incineration standards already established in Part 503. Id.

at 9276-9277.

Both the 1980 RCRA preamble and the CWA Part 503 ru lemaking history, including the discussion of how Parts 257 and 258 apply when sewage sludge is perma nently placed on land surfaces for disposal purpose s, show the primacy of the CWA § 405 program with resp ect to the regulation of sewage sludge. 45 Fed. Re g. at 33101; 58 Fed. Reg. at 9261. These are all illustra tive of the careful harmonization among CWA, RCRA a nd CAA requirements that EPA undertook in crafting the Par t 503 regulations that serve as the cornerstone of proper sewage sludge management. EPA must not undo this c arefully crafted reconciliation of statutory author ities as it seeks to address its obligations and, indeed, it would be arbitrary and capricious for EPA to do so

.

This history of the RCRA and CWA interplay specific ally related to sewage sludge indicates that Congre ss provided a thoughtful framework for how to safely a nd effectively exempt sewage sludge management from RCRA regulation, except in the case where the sewag e sludge was hazardous. This framework cannot be reconciled with an approach by which all sewage slu dge would be regulated as solid waste.



## B. Part 503 Distinguishes Sewage Sludge and Solid Wast e

In keeping with this framework, EPA’s careful regul atory approach in the Part 503 regulations distingu ishes between sewage sludge and solid waste. This is con sistent with the distinctions drawn by Congress, an d by EPA in its implementing regulations, that sewage sludge management is not the same as solid waste disposal

. See,

e.g., 40 CFR Part 503 (identifying distinct standards f or land application (Subpart B), surface disposal ( Subpart C), or incineration (Subpart E) of sewage sludge); 58 Fed. Reg. at 9256-57 (distinguishing between sew age use and disposal methods).

In addition, EPA’s description of sewage sludge as it moves through the wastewater treatment process i ndicates recognition that solids and dissolved substances ar e still present in sewage sludge before and after i t is processed, and, following treatment, sewage sludge contains the residues of domestic sewage. 13 This recognition indicates that EPA has always intended sludges being generated and processed during and af ter wastewater treatment, to be exempt from RCRA regula tion when managed in accordance with the Part 503 regulations. EPA and Congress recognized that regu lating the wastewater treatment process, which is f ully regulated under the CWA, under RCRA would be duplic ative.

Other EPA guidance also demonstrates the distinctio n the Agency has consistently made between biosolid s and solid waste. For example, EPA’s “Plain English Guid e to the EPA Part 503 Biosolids Rule” (EPA/832/R-93 /003 September 1994) states:

13 58 Fed. Reg. at 9255-9256 (observing that unproces sed sewage sludge contains the solids and dissolved substances that were present in wastewater and that treatment processes also result in the development of sludge that contains organic materials and constituents that were present in the wastewater).

### NACWA Letter to EPA on Sewage Sludge Incineration Page 13 of 18 September 9, 2009

If municipal solid waste accounts for more than 30% (by dry weight) of the mixture of biosolids and auxiliary fuel, however, the municipa l solid waste is not considered auxiliary fuel under Part 503. (Instead, the process would be cove red by 40 CFR Part 60 and 61.) 14

Also § 503.41(b) of the Part 503 Rule states:

Auxiliary fuel is fuel used to augment the fuel val ue of sewage sludge. This includes, but is not limi ted to, natural gas, fuel oil, coal, gas generated duri ng anaerobic digestion of sewage sludge, and munici pal solid waste (not to exceed 30 percent of the dry we ight of sewage sludge and auxiliary fuel together). Hazardous wastes are not auxiliary fuel.

All of this means that EPA must be extremely carefu l in any discussion that would imply that the Domes tic Sewage Exclusion does not apply to these sludges. How EPA explains what it considers to be the scope of the Domestic Sewage Exclusion could have major impacts not only with respect to sludges still awaiting dec isions about use or disposal, but also the regulatory stat us of the treated wastewater, which EPA has long re cognized is “still considered to be domestic sewage for purpose s of the Act [following treatment and solids remova l in such treatment].” 44 Fed. Reg. 53,438, 53,440 (Sept. 13 , 1979).

In sum, Congress’ intent with CWA § 405 and the Dom estic Sewage Exclusion under RCRA was to ensure tha t sewage sludge was not subject to regulation as soli d waste as long as it is properly managed under Par t 503 requirements. These requirements, as noted, pull i n RCRA-based requirements for land-based disposal o f sewage sludge. As such, the general rule is clear t hat the generation and management of sewage sludge, including the beneficial uses or disposal of sewage sludge, are not solid wastes for RCRA regulatory p urposes, as long as the management of these sludges complies with Part 503 regulations. EPA must be consistent with this past regulatory determination and ensure it cr eates no conflicts between the CWA and RCRA in its Subtitle

D definition of solid waste.



## C. Serious Consequences Would Ensue if EPA Asserts tha t the Domestic Sewage Exemption Only Applies up to a POTW’s “Headworks”

The framework noted above is clearly based on the u nderstanding that solids moving through the wastewa ter treatment process, including sludges generated in t hat process, are subject to the Domestic Sewage Exc lusion. This is consistant with the RCRA § 1004(26A) and (2 7) definitions of solid waste and “sludge,” which a re tied to “discarded” and “waste” language and concepts. Sew age sludge generated by the treatment process may b e beneficially used in a number of ways. Therefore, to deem it solid waste as it is generated in the tr eatment process, or even as it undergoes further processing prior to being removed “from” the treatment plant, contravenes these fundamental RCRA principles. Cas e law under RCRA is clear that the statute regulate s as solid wastes only truly discarded materials. Cordiano v. Metacon Gun Club, Inc. , 2009 U.S. App. LEXIS 16980 (2d Cir. July 31, 2009) (discussing at length the defin ition of “solid waste” and noting that RCRA require s a showing that materials are “discarded”).

14 Page 81, third paragraph, second sentence.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 14 of 18 September 9, 2009

In fact, not all sewage sludge is discarded or disp osed; indeed, some is beneficially used by recyclin g nutrients to farm land or generating energy in combustion units. EPA has recognized this in the Part 503 distincti ons between use and disposal. This regulation already provides a cogent, well-thought out and well-unders tood

framework. There is no need for EPA to invent a ne w framework for purposes of an unrelated and inappl icable

CAA provisions.

In addition, the Domestic Sewage Exemption applies without condition to “solid or dissolved material i n domestic sewage.” A practical consideration of wha t this means in the context of POTW operations also demonstrates the illogic of EPA seeking to apply th e Domestic Sewage Exclusion at a POTW’s headworks.

For example, solids in domestic sewage do not drop out at the headworks of a POTW; instead, solids tha t enter the headworks are part of what is treated during th e treatment process. Thus, disconnecting the Domes tic Sewage Exclusion at the headworks is contrary to th e statutory definition and common sense. Moreover, sewage sludge is both a product of the wastewater t reatment process as well as material that provides a treatment function during this process. Applying t he Domestic Sewage Sludge Exclusion at the headwork s fails to recognize this and, again, would violate the sta tutory definition. Finally, decisions about use or disposal occur after this processing is complete. If EPA ap plies the Domestic Sewage Sludge Exclusion at the h eadworks, this dictates a regulatory status for treatment pro cess material well ahead of decisions about its man agement disposition. This approach will severely limit loc al choices about sewage sludge management, which is directly contrary to the requirements of CWA § 405.

This practical review demonstrates that a regulatio n that would apply the Domestic Sewage Exclusion on ly up to the headworks of a POTW would ignore how the was tewater treatment process works in reality and unde rcut the broad RCRA exemption Congress intended for CWA- regulated POTW operations. The unintended result of such a reading would be to give POTWs hazardous was te generator responsibilities for material that ent ers the

treatment works, see, e.g. , 40 CFR 262.4 (hazardous waste determination). Su ch an outcome is contrary to Congress’ intent, as Congress created the Domestic Sewage Exclusion to avoid duplicating CWA regulatio ns already being implemented by POTWs with new RCRA ob ligations.



## D. EPA’s Suggested Approach Would Violate RCRA § 1006( b)

RCRA § 1006(b) requires EPA to integrate RCRA requi rements with the requirements of the CWA and the CA A, as well as other laws. EPA is reportedly consideri ng an approach that would deem sewage sludge a soli d waste in order to promulgate a rule under a CAA provision that does not even apply to POTWs. Such an action would violate EPA’s non-discretionary duty under RCRA. F urthermore, developing an interpretation of the Dom estic Sewage Exclusion or of the definition of solid wast e that eviscerates the CWA § 405 program like wise would violate EPA’s duty of integration. Nothing in CAA § 129 suggests Congress intended the Draconian appr oach EPA is reportedly considering. Indeed, CAA § 129(g ) explicitly states that the definitions contained therein (including the definition of solid waste incinerati on unit and of solid waste) are for purposes of CAA § 306 [federal procurement] and “this section only ” (emphasis added). Thus, any effort by EPA to dev elop a broadly applicable definition of nonhazardous solid waste g oes well beyond what is authorized by or required t o implement CAA § 129.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 15 of 18 September 9, 2009

In sum, any definition of solid waste or regulatory provision that would subject POTWs to regulation u nder

RCRA would violate several other federal laws and w ould wreak havoc on existing and longstanding regul atory programs for safe and effective sewage sludge manag ement programs that are protective of human health and

the environment. Furthermore, such action is unnec essary for EPA to fulfill its duties under CAA § 12 9, since that provision does not apply to POTWs or SSIs.



## E. SSI Emissions Are Already Stringently Regulated Und er Part 503 / CWA § 405

Emissions from SSIs are already heavily regulated b y other Congressionally-mandated, comprehensive regulations that are adequately protective of human health and the environment. Accordingly, no publi c health

or environmental benefit will be realized from the expensive control measures that CAA § 129 would imp ose if SSIs were erroneously included in the EPA’s propose d rule for solid waste combustion sources.

Since 1993, POTWs that practice incineration have b een subject to a comprehensive, risk-based program for reducing the potential environmental risks of sewag e sludge pursuant to CWA § 405 and the implementing regulations set forth Part 503. Section 405(d) of the Clean Water Act requires EPA to establish numer ic limits and management practices that protect public health and the environment from the adverse effects of to xic pollutants in biosolids.

Section 405(e) of the Clean Water Act prohibits any person from disposing of sewage sludge from a POTW or other treatment works treatin g domestic sewage through any use or disposal pract ice for which regulations have been established pursuan t to § 405, except in compliance with the Part 503 regulations.

In Part 503 regulations, EPA has identified the pol lutants in sewage sludge that may adversely affect public health or the environment and has specified the man agement practices for the utilization and disposal of sewage sludge that are protective of public health and the environment. For disposal by incineration, the Part 503 regulations require, among other requirements:

(i) numerous management practices and general requireme nts;

(ii) risk-based, site-specific limits for arsenic, cadmi um, chromium, lead, and nickel content in the sewage sludge incinerated;

(iii) compliance with National Standards for Hazardous Ai r Pollutants (NESHAPs) for mercury and beryllium (as discussed below);

(iv) operational technology-based emission limits for to tal hydrocarbon (THC) or an alternative emission limit for carbon monoxide (CO) ; and

(v) monitoring, recordkeeping and reporting requirement s.

40 CFR Part 503, Subpart E.

### NACWA Letter to EPA on Sewage Sludge Incineration Page 16 of 18 September 9, 2009

Furthermore, in the course of developing the Part 5 03 regulations, EPA also proposed to establish requ irements for dioxins (including specific congeners of dioxin , dibenzofuran, and coplanar PCBs). 15 However, after evaluating the emissions from dioxins from sewage s ludge incineration, as well as surface disposal and land application, EPA decided such requirements were not warranted. 16 This decision was based on the results of a comprehensive risk assessment that demonstrated tha t dioxin levels in biosolids and biosolids incinera tor exhaust gases do not pose a significant risk to hum an health or the environment. 17

As explained in detail in NACWA’s 1997 comments to EPA (pages 15-17), the numeric emission limits and management practices requirements established under the Part 503 regulations were derived from years o f study and evaluation of the potential risks to huma n health and the environment which could be posed by the incineration of biosolids. The regulation of SSIs under this existing regime are risk-based standards that were developed to protect human health and the environme nt from any reasonably anticipated adverse effects from pollutants that may be present in sewage sludge. I n fact, the Part 503 regulations for SSIs were deve loped through a partnership between EPA’s water and air o ffices – a partnership that continues today as EPA

conducts its mandated review of the Part 503 standa rds. As a result, SSIs can clearly demonstrate that the

emissions from their units are not adversely impacting human health and the environment by demonstrating compliance with the Part 503 requirements. Moreove r, the statutory framework of this regime provides for ample means for EPA to identify and regulate additi onal concerns if supported by scientific evidence. For example, CWA § 405 provides for a biennial review p rocess that was specifically established for identi fying and regulating any additional pollutants of concern. E PA has repeatedly emphasized its confidence that th e Part 503 regulations are adequately protective of public health and the environment. 18

Additionally, since 1975, EPA has imposed NESHAPs f or mercury and beryllium emissions which apply to

certain SSIs. See

40 CFR Part 61, Subpart E and C. The mercury NESH AP applies, in relevant part, to any source that incinerates wastewater treatment plant sludge and imposes emission limits for mercury, as well as imposes stack testing, sampling, and monitoring req uirements. See 40 CFR Part 61, Subpart E. The beryllium NESHAP applies, in relevant part, to incinerators w hich process beryllium-containing waste and imposes emission limits for beryllium, as well as sampling requirements. See 40 CFR Part 61, Subpart C. These NESHAPs are expressly incorporated into the 40 CFR Part 503 requirements for POTWs.

Since 1974, EPA has also imposed New Source Perform ance Standards (NSPS) for SSIs under CAA § 111. See 40 CFR Part 60, Subpart O. These regulations apply to any incinerator constructed or modified after June 11, 1973 that (1) combusts wastes containing more than 10% s ludge (dry basis) produced by municipal sewage trea tment plants; or (2) charges more than 1,000 kg (2,205 lb s.) per day municipal sewage sludge (dry basis). See 40 CFR § 160.150. Under the existing NSPS for SSIs, regulat ed incinerators must comply with emission limits fo r particulate matter and opacity, as well as operatio nal, monitoring, testing and reporting requirements

.

Thus, of the eleven pollutants identified in CAA § 129, many are already directly regulated under EPA regulations at Parts 503, 60, or 61, including tota l particulate matter, opacity, lead, cadmium, mercu ry, and CO

15 See Standards for the Use or Disposal of Sewage Sludge: Proposed Rule , 64 Fed. Reg. 72,045 (Dec. 23, 1999).

16 See Standards for the Use or Disposal of Sewage Sludge: Final Notice , 66 Fed. Reg. 66,028 (Dec. 21, 2001).

17 See id.

18 See Letter from James A. Hanlon, Director of EPA Offic e of Wastewater Management, to Greg Kester, State o f Wisconsin Department of Environmental Resources (Sept. 20, 2004) (“EPA b elieves that 40 CFR Part [503] regulations are prot ective of public health and the environment and we continue to support biosolids ma nagement in full compliance with the Part 503 regul ation.”) (attached hereto at Attachment C).

### NACWA Letter to EPA on Sewage Sludge Incineration Page 17 of 18 September 9, 2009

(optional, as a surrogate for THC). CAA § 129(a)(4 ); 40 CFR Parts 60, 61, 503. Additionally, EPA and NACWA have both also determined that SSIs are only very m inor sources of several other of the CAA § 129 poll utants, including dioxins, sulfur dioxide, and hydrogen chl oride. NACWA’s March 17, 1997 comment letter (page s 13- 14) documents in detail many specific examples of e xisting SSI regulations, or information regarding e missions from SSIs, for each of the pollutants listed in § 1 29.

In addition to the federal requirements applicable to SSIs outlined above, public agencies operating S SIs are also required to obtain a Title V operating permit if they are “major sources” as defined by the CAA. Pursuant to 40 CFR Part 403, POTWs additionally implement, t hrough local regulatory authority, pretreatment standards to prevent discharge of pollutants to the POTW that may pass through or interfere with treat ment processes. Pretreatment is an effective way to red uce harmful constituents in the sewage sludge combu sted by SSIs. States also have authority to regulate and, in fact, do regulate air emissions from SSIs under their respective CAA State Implementation Plans. Togethe r, these federal, state, and local regulations form an existing and effective regulatory scheme for regula ting emissions from SSIs. Further regulation of S SIs under § 129 is not appropriate or necessary for the prote ction of public health and the environment.

EPA appears to have agreed with this analysis 19 and nothing in the NRDC decision undermines this result.



## F. Regulation of SSIs under CAA § 129 Would Result in Prohibitive Costs and Only Negligible Beneficial Impacts.

Congress’ decision not to include SSIs among the ca tegories of combustion sources covered by CAA § 129 , and EPA’s longstanding recognition of this exclusion, i s also supported by an analysis of costs and benefi ts. The additional regulatory burdens imposed under CAA § 1 29 would be substantial to SSI operators, while off ering no discernable corresponding benefits. The added c osts then imposed upon POTW ratepayers would be considerable, and could potentially lead to the eli mination of incineration as a biosolids management option for many communities.

Costs would invariably increase under CAA § 129 as SSI operators face competing MACT standards for pollutants that cannot be simultaneously achieved ( e.g., NO

x and CO). For further discussion see NACWA’s 1997 comment letter (pages 17-19).

An overwhelming cost or regulatory burden on SSIs w ould be inconsistent with EPA’s declarations that incineration is a safe and acceptable sewage sludge disposal method. It would also be contrary to the congressional intent expressed in CWA § 405, in whi ch Congress mandates that EPA must provide for safe management practices for the use and disposal of bi osolids, and not to dictate “preferred” practices a nd eliminate others. For example, CWA § 405(e) states that “[t]he determination of the manner of disposa l or use of sludge is a local determination,” as long as the practice is in accordance with EPA’s regulations.

19 72 Fed. Reg. 2620, 2620-2624 (Jan. 22, 2007) (eval uating CAA § 129, its legislative history, and poli cy considerations to determine that (1) “EPA has the discretion to define which categor ies of combustion units should be subject to regula tion under CAA § 129” and that SSI would be regulated under CAA § 112); 72 Fed. Re g. at 2627 (acknowledging that “various CWA and CAA regulations currently apply to SSI” and that “[t]hese other regulations provide some additional support for our decision not to re gulate under CAA § 129 because these other regulations provide protection of human health and the environment for many of the polluta nts regulated by CAA § 129 regulations”).

### NACWA Letter to EPA on Sewage Sludge Incineration Page 18 of 18 September 9, 2009

For all of these reasons, NACWA believes that EPA h as properly interpreted CAA §§ 112 and 129 to concl ude that § 112, not § 129, applies to POTWs and SSIs. This determination under the CAA is fully consisten t with the CWA and RCRA authorities and requirements discu ssed herein. As such, it is unnecessary, and would be very problematic as described herein, for EPA to de velop a definition of solid waste for the purposes of CAA § 129 that inadvertently eviscerates longstanding and well-understood programs for sewage sludge managem ent developed over many years under the CWA and RCRA.

I look forward to discussing this matter with you a nd your staff. Please contact me at 202-833-4653 o r Chris Hornback of my staff at chornback@nacwa.org should you have any questions.

Sincerely,

Ken Kirk

Executive Director