### NACWA’s Comments on EPA Reconsider a tio n of Sewag e Sludg e Inci neration
August 14, 2006 Page 1 of 15

August 1 4 , 2 006

EPA Dock et Center (EPA /DC)

United Sta t e s Environme ntal Pro t e c ti on Agency U.S. EPA ( M D-6102T) 1200 Pennsylvania Aven ue NW Washington, D.C. 2 0460



### Re: Comments of the National Association of Clean Water Agencies (NACWA) on U.S.

EPA’s Standards of Performance for New Statio nary Sources and Emission Guidelines for Existing Sources: Other Solid Wast e Incineration Units : Recon s idera tion

Attention Docket ID No. EPA-HQ-OAR-2003-0156

Dea r Sir o r Mada m:

These comm ents are sub m itted on behalf of the National Asso ci ation of Cl ean Water A g encie s (“NACWA”) 1 in suppor t o f the Uni t ed States Envir onmental Pr otec tion Ag e n cy’s (“U

. S. EPA” or the “Agenc y”)

determ inati o n that sewa ge sludge inc i nerato rs (“S S Is” ) ar e not subjec t to re gulation a s o t her solid wa st e
incinera tion units ( “ OSWIs”) pursua nt to S e ction 129 of the Clean Air Act ( “ CAA”). NACWA submits these

comm ents i n response to U.S. EPA’ s June 28, 200 6 noti c e of its r econsi d er ation of

, and reque s ts for public

comments o n , the issu e of wheth e r S S Is should b e ex cluded from the CAA § 129 regula tions for OS WIs promulga ted on December 16, 2005 (the “final OSWI rule”). 2

Wh ile NAC W A u n d er st an ds an d su pport s U

. S. E P A’s ef fort s to en sure a f u ll oppor t unity for publ ic

comm ent in its rulemaki ng process, NACWA r e spectfu ll y submits that U. S. EP A has alread y prop erly

det e rm ined — af ter thor ough evaluation a n d a n al y s i s — t h at SSI s ar e not s u bject to regulation as OSWIs under

CAA § 129. This determination is the result o f 10 years o f notice and comm ent rulema king, judicia l challenges and negoti ations involvi n g all in ter e sted par t ies. A ddi tional p u blic co mm ent during r econsi d era t i o n is not

expe cted to genera te ne w infor m ati o n. As su ch

, th is proc es s sh ou ld on ly serv e to rein f o rce U.S. E P A’s dec i sion

to ex clude SSIs fro m the final OSW I r u le to pre s e r ve inci neration as a sa fe, viable, and cost-effectiv e biosolid s (or “ s ewag e sludge”) man a gem e nt p r a c ti ce consi s tent wi th the intent o f Co ngress and U

. S. EPA. 

### According l y,

1 NACWA (f

or merly the As s o ciation o f Metrop olitan Se werage Agenc i es or A M SA ) represents the interests of n e arly 300 publicly owne d waste w ater treatment a g e n cies or works (P OT Ws) na tionwide. NA CWA's mem b ers serve the majority of

the sew e red population in the United Sta t es, and collectively treat and reclaim more than 18 billion gallo ns of w a stew ater each day.

2 Se e Standards of Performance for New Stationa ry Sourc e s and Emissio n s Guid elines for Existing So urces: Other Solid Waste

Inci neration Units: Recon s ider ation , 7 1 Fed. Reg

. 36 72 6 (June 28

, 2 0 0 6 ) ; Standards of P erformance for New St at

ionary Sourc e s and Emission Guidelines for Existing Sources: Ot her Solid Waste Incineration Units; Final Rule , 7 0 Fe d. Reg. 7 4 8 7 0 (Dec. 16, 20 05 ).

### NACWA’s Comments on EPA Reconsider a tio n of Sewag e Sludg e Inci neration
August 14, 2006 Page 2 of 15

NACWA strongly supports U.S. EPA’s decision not to incl ude SSIs among the categori es of OSWIs regulated

under the final OSWI rule.



### GENERAL COMMENTS

1. NACWA’s Public Agency Members Rely on I ncineration as a Safe, Effective, and Federally-Approved Bioso lids Management Practice.

NACWA represents the interests of the country’s wa stewater treatment agencies, true environmental practitioners that serve the majority of the sewered popu lation in the United States , and collectively treat and reclaim more than 18 billion gallons of wastewater each day. For over thirty-six years, NACWA has maintained a leadership role in issues affecting POTWs, and has been at the forefront of the development and implementation of scientifically-based, technically-s ound, and cost-effective environmental programs for protecting public and ecosystem health.

The approximately 16,000 POTWs loca ted in the United States utilize U.S. EPA-approved methods to manage the estimated eight million dry metric tons of biosolids that are generated annually as a product of their wastewater treatment activities. These approved methods include incineration. As U.S. EPA has repeatedly stated, the Agency does not have a positi on regarding the biosolids management options most suitable for a particular community and, instead, recogn izes that such choices are local decisions (subject, of course, to applicable fede ral and state regulations). 3 U.S. EPA also stated that it continues to support incineration (as well as land application, and disposal at municipal solid waste landfills and disposal at surface disposal sites) as a viable option for the management of biosolids. 4

The incineration of biosolids results in an 80-95% reduction in volume, the effective destruction of pathogens, the degradation of toxic organic compounds, and the production of a sanitary, odorless, and nonhazardous by-product ( i.e. , ash). Incineration is thus an import ant, safe, and effective component of the biosolids management practices utilized by POTWs. U. S. EPA has estimated that, in 1998, up to 22% of biosolids generated at POTWs located within the Unit ed States is disposed of through incineration. 5 Using this and other available surveys, NACWA has estimated that 17% of the biosolids generated by U.S. POTWs is presently managed through incineration.

3 Letter from Benjamin H. Grumbles, then Acting Assistant Administrator for the Office of Water, U.S. EPA, to Scott Hassett, Secretary of Wisconsin Department of Natural Resources dated October 7, 2004 (attached hereto at Attachment B) (“we do not believe that EPA should be involved in determining the biosolids ma nagement practices most suitable for a particular community”); James A. Hanlon, Director of U.S. EP A Office of Wastewater Management, to Greg Kester, State of Wisconsin Department of Environmenta l Resources dated September 20, 2004 (attached hereto at Attachment C).

4 See id.

5 See United States Environmental Protection Agency, Biosolids Generation, Use, and Disp osal in the United States 26-27 (1999) (EPA No. 530R-99-009), available at www.epa.gov/epaoswer/non-hw/compost/biosolid.pdf.

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2. U.S. EPA’s Decision Not to Regulate SSIs under CAA § 129 was Reached After Thorough and Complete Evaluation of the Issue.

Given the importance of incineration to NACWA members and the non-member POTWs that practice
incineration, NACWA has been an active participant in U.S. EPA’s evaluation of the emissions from sewage sludge incineration and the Agency’s regulatory actions related to SSIs. During this process, NACWA has cooperatively provided U.S. EPA with data and other information about its member s’ biosolids incineration activities and the level and types of pollutants released during this process in orde r to assist the Agency in evaluating the applicability of CAA §§ 129, 112(d), and 112(k). NACWA has also been heavily involved in U.S. EPA’s development of the existing regulations under the CAA and Clean Water Act (“CWA”) pertaining to emissions from POTWs and SSIs, including 40 CFR Part 503 (Standards for the Disposal of Sewage Sludge) and 40 CFR Part 63, Subpart VVV (National Emissions Standards for Hazardou s Air Pollutants: Publicly Owned Treatment Works).

NACWA’s history of involvement in this specific regulatory issue span s nearly a decade, beginning with

U.S. EPA’s notice of its initial intent to include SSIs as a category of OSWIs under CAA § 129(a)(1)(E). 6 In response to U.S. EPA’s notice, NACWA (then named the Association of Metropolitan Sewerage Agencies or AMSA) and many of its individual member agencies prov ided extensive comments to U.S. EPA, which explained in detail the many reasons that SSIs should not be included as OSWIs und er CAA § 129. As discussed in
NACWA’s March 17, 1997 comment letter, these reasons include:

(i) The regulation of SSIs under Section 129 is beyond the U.S. EPA’s statutory authority;

(ii) U.S. EPA’s contemplated method for es tablishing Maximum Achievable Control Technology (“MACT”) Standards for SSIs under Section 129 would lead to results contrary to the intent of Congress – i.e., it would lead to the elimination of biosolids incineration (a
safe, viable and cost-effective sewa ge sludge management practice);

(iii) The properties of biosolids are very different from those of hazardous, medical or municipal solid wastes. Thus, SSIs should not be subject to the same type of regulations imposed on these other types of incinerators;



### (iv) The emissions from SSIs are already subject to comprehensive and stringent regulations that are protecti ve of human health and the environment. U.S. EPA has determined that, through compliance with the Part 503 limits and management practices under the CWA, emissions from SSIs do not adversely affect human health and the
environment; and

(v) Accordingly, no environmental benefit will be realized from the expensive and/or

infeasible control measures that Section 129 w ill impose, and there may be a net loss of

environmental benefit.

6 New Source Performance Standards and Emissions Guidelines: Sewage Sludge Incinerators , 62 Fed. Reg. 1868 (Jan. 14, 1997).

### NACWA’s Comments on EPA Reconsider a tio n of Sewag e Sludg e Inci neration
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NACWA’s March 17, 1997 comments to U. S. EPA remain fully applicable to the issues raised by U.S. EPA’s
current reconsideration of the final OSWI rule, and ar e accordingly attached hereto as Attachment A and incorporated by reference.

Following the close of the public comment period in 1997, U.S. EPA evaluated NACWA’s and other interested parties’ comments, conducted legal analysis, and further studied SSIs. This process was completed, in part, through the Industrial Combustion Coordinate d Rulemaking Advisory Committee convened under the Federal Advisory Committee Act (“FA CA”) on which NACWA member agencies participated extensively and provided their technical expertise and experience. During this three year process, NACWA and its member agencies provided U.S. EPA with significant inform ation regarding its members’ biosolids incineration activities and the emissions released during this process. After U.S. EPA’s full eval uation and consideration of the applicability of Section 129 to SSIs, U.S. EPA properly determined that SSIs should not be regulated under CAA § 129 because they do not constitute “solid waste incineration units.” U.S. EPA accordingly announced

that decision in its semiannua l regulatory ag enda for 2000. 7 U.S. EPA reiterated this determination when it announced in November 2000 that the Agency would complete the CAA § 129 re gulations for OSWIs by
November 15, 2005, and confirmed the sources that would be covered by the OSWI ru lemaking – tellingly, SSIs were not among those sources. 8

Further demonstrating its intent not to regulate SS Is under CAA § 129, U.S. EPA provided an express exemption from the final CAA § 129 rules promulgated in December 2000 for commercial and industrial solid waste incinerators. SSIs complying with 40 CFR Part 60, Subpart O (Standards of Performance for Sewage Treatment Plants) are expressly excluded from this incinerator rule. 9

7 United States Environmental Protection Agency, Unified Agenda, April 2000 Agenda of Regulatory and Deregulatory Actions , 65 Fed. Reg. 23430, 23460 (April 24, 2000). In th e regulatory agenda, U.S. EPA expressly stated:

The Agency has decided not to regulate sewage sludge incinerators as a category under Section 129 of the Clean Air Act. Section 129(a)(1) requires the Agency to establish standards under Section 129 for each category of “solid waste incineration units.” “Solid waste incineration unit” is defined as a “distinct operating unit of any facility which combusts any so lid waste material from commercial or industrial establishments or the general public (including single and multiple residences, hotels, or motels).” The Agency believes that sewage sludge generated by publicly-owned treatm ent works (POTWs) and combusted in SSIs is “solid waste.” However, this sludge is from a municipal source, and not from “commercial or industrial establishments or the general public.” Therefore, SSIs that combust this sludge are

not “solid waste incineration units” and section 129 does not apply to them . Virtually all of the SSIs that would be candidates for regulation combust sludge from PO TWs, and thus are not covered under Section 129.

8 Standards of Performance for New Stationary Sources and Emission Guidelines for Existing Sources for Other Solid Waste Incinera tor

Units , 65 Fed. Reg. 67357 (Nov. 9, 2000).

9 Standards of Performance for New Stationary Sources and Emission Guidelines for Existing Sources: Commercial and Industrial Sol id

Waste Incineration Units , 65 Fed. Reg. 75338, 75351 (Dec. 1, 2000); see also 40 CFR § 60.2020(m).

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NACWA also intervened in support of U.S. EPA in the litigation initiated by Sierra Club (the petitioner for this reconsideration proceeding) in federal court in 2001 to compel the Agen cy to issue performance standards and other requiremen ts under CAA § 129 for OSWIs. 10 In the legal filings and discussions in this lawsuit, NACWA again explained that U.S. EPA had alre ady made a determination not to regulate SSIs under CAA § 129 and, therefore, the Agency was not required to promulgate performance standards or other requirements for SSIs under that section of the CAA. Wh ile this litigation resulted in a settlement in which U.S. EPA agreed to establish a schedule for promul gating the standards for OSWIs under CAA § 129, the settlement did not alter or affect the Agency’s earlier de termination that SSIs are not an OSWI category subject to regulation under Section 129(a)(1)(E).

U.S. EPA accordingly did not include SSIs among the ca tegories of OSWIs in the proposed OSWI rule in

December 2004 or in the final rule in December 2005. 11 U.S. EPA’s basis for doing so was clear — the Agency had already made clear that it determ ined that SSIs were not a category of OSWIs subject to regulation under CAA § 129. While Sierra Club contends in its petition for reconsideration that there was no opportunity to

comment on U.S. EPA’s decision not to include SSIs in the OSWI proposed rulemaking , EarthJustice did in fact comment on this specific issue in its co mment letter on the proposed OSWI rule. 12 In response to EarthJustice’s comment, U.S. EPA again articulated that, as early as April 2000, the Agency indicated that it no longer intended to regulate SSIs under CAA § 129 and made clear that it intended to instead regulate SSIs under CAA § 112 to the extent that additional regula tion beyond 40 CFR Part 503 is required. 13

Given this extensive regulatory history, NACWA believes the various rulemaking activities taken by U.S. EPA over the past decade related to this issue firmly es tablish that U.S. EPA has al ready thoroughly considered whether SSIs are subject to regulation as OSWIs und er CAA 129, and has reasonably and appropriately determined that they are not. Nevertheless, in light of U.S. EPA’s reconsideration of this issue, NACWA provides the following additional comments in further support of U.S. EPA’s prop er determination that SSIs are sufficiently regulated under other regulatory programs.

10 Sierra Club v. Whitman et al ., Case No. 1:01CV01578 (D.D.C.).

11 Standards of Performance for New Stationary Sources and Emission Guidelines for Existi ng Sources: Other Solid Waste Incineratio n Units: Proposed Rule , 69 Fed. Reg. 71472 (Dec. 9, 2004); Standards of Performance for New Stationary Sources and Emission Guidelines for Existing Sources: Other So lid Waste Incineration Units: Final Rule , 70 Fed. Reg. 74870 (Dec. 16, 2005).

12 See Comments of EarthJustice, page 4 (Docket No . EPA-HA-OAR-2003-0156-0070) (Feb. 7, 2005).

13 Standards of Performance for New Stationary Sources and Emission Guidelines for Existi ng Sources: Other Solid Waste Incineratio n (OSWI) Units: Summary of Public Comments and Responses , pages 57-58 (Docket No. EPA-HQ-OAR-2003-0156-0104).

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SPECIFIC COMMENTS

1. U.S. EPA Properly Exercised its Disc retion Under the CAA in Reasonably Determining that SSIs Should Not Be Included as a Category of OSWIs in the Final

OSWI Rule.

U.S. EPA was well within its discretion to exclude SSIs from the final OSWI rule. Congress expressly directed U.S. EPA to regulate certain categories of inci neration enumerated in Sections 129(a)(1)(A)-(D) of the Act. The statute does not define the categories of “oth er” solid waste incineration units that must be regulated under CAA § 129(a)(1)(E). Therefore, i nherent in U.S. EPA’s implementation of CAA § 129 is the discretion for the Agency to reasonably define what constitutes the statutorily undefined “other categories” of solid waste

incineration units and then determine which of thos e categories warrant regulation under CAA § 129.

This conclusion is firmly supported by the text of CAA § 129. Notabl y, while the statute provides firm timelines for the promulgation of standards and other re quirements for specifically identified categories of solid waste incinerators ( e.g. , municipal waste incinerators, commercial and industrial waste incinerators, and hospital and medical waste incinerators), the CAA then only states that U.S. EPA must publish a schedule for the promulgation of standards for statutor ily undefined “other categories of solid waste incineration units.” CAA § 129(a)(1)(E). Thus, CAA § 129 plainly does not require U.S. EPA to promulgate OSWI standards for “every” or “all” possible categories of solid waste incineration units, without any consideration of the size of the incinerator or its impact on pub lic health and the environment.

An interpretation of CAA § 129 that would includ e all solid waste incineration units is not only inconsistent with the statutory language, but is also illogical because it would require U.S. EPA to expend a tremendous amount of federal Agency resources to develop MACT standards for every category of such units, regardless of the level of actual emissions from the units. Congress simply could not have required this result by merely directing U.S. EPA to publish a schedule fo r the promulgation of standards applicable to “other categories” of solid waste incineration units.

Moreover, if Congress truly intended such far-re aching consequences, the legislature would have provided that directive to U.S. EPA within the text of CAA § 129(a)(1)(E). In other words, Congress would have instructed U.S. EPA to regulate “all” or “every” othe r category of solid waste incineration units. To the contrary, such an intent by Congress is noticeably absent in the text of C AA § 129 or its legislative history. As discussed below, the legislative history actually indicate s that, in drafting CAA § 129, Congress was primarily concerned with regulating incinerators burning municipal waste. Congress di d not direct U.S. EPA to regulate SSIs or any other specific type of incinerators under the OSWI category.

For all of these reasons, Section 129 is clearly ambigu ous with respect to the “o ther categories” of solid

waste incineration units that must be regulated under CAA § 129(a)(1)(E). Co ngress’ instructions to the Agency to publish a schedule for the promulgation of standards for “other categories” of solid waste incineration units, therefore, inherently includes the authority for U.S. EPA to reasonably delineate which categories of

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incinerators should be subject to regu lation as OSWIs. U.S. EPA properly exercised that authority by collecting and analyzing information regarding potential OSWIs and ultimately concluding that SSIs should not be regulated as a category of OSWIs. As discussed below, this determination was a reasonable exercise of U.S.

EPA’s discretion under the Act.



### A. U.S. EPA’s Regulation of SSIs und er CAA § 112 Prevents the Regulation of SSIs under CAA § 129.

As an initial matter, U.S. EPA can not include SSIs among the categories of O SWIs to be regulated by the final OSWI rule because U.S. EPA has already determined that SSIs are more properly regulated under CAA § 112. Section 129(h)(2) clearly states that: “no solid wa ste incineration units subjec t to performance standards under [Sections 129 and 111] sh all be subject to standards under [Secti on 112(d)].” Thus, the language of Section 129(h) makes clear that U.S. EPA’s regulation of sources under CAA § 129 or CAA § 112 must be mutually exclusive. As U.S. EPA ha s rationally concluded, any unit that is subject to CAA § 112 standards can not be subject to CAA § 129.

SSIs are subject to regulation under CAA § 112, as U. S. EPA has already identified SSIs as an area source category under CAA § 112. After initially listing SSIs as a hazardous air pollutant (“HAP”) “source category” under CAA § 112, U.S. EPA subsequently determined that the SSI category did not have any sources with the potential to emit HAPs at a level approaching major source levels. 14 In 2002, U.S. EPA then included SSIs as an additional area source category und er CAA §§ 112(c)(3) and 112(k)(3)(B)(ii). 15 Since area source categories are subject to the promulgation of em ission standards under CAA § 112(d), SSIs may not also be subject to regulation under § 129.



### B. Emissions from SSIs and POTWs are Already Stringently Regulated.

U.S. EPA’s decision not to regulate SSIs as OSWI s under CAA § 129(a)(1)(E) is also reasonable and appropriate given that emissions from SSIs are already heavily regulated by other Congressionally-mandated, comprehensive regulations that are adequately protective of human health and the environment. Accordingly, no public health or environmental be nefit will be realized from the expensive control measures that CAA § 129 would impose if SSIs were erroneously included in the final OSWI rule.

Since 1993, POTWs that practice incineration have been subject to a comprehensive, risk-based program for reducing the potential environmental risks of sewage sludge pursuant to Section 405 of the CWA

14 See National Emission Standards for Hazardous Ai r Pollutants: Revisions of Source Category List under Section 112 of the Clean Air

Act , 67 Fed. Reg. 6521 (Feb. 12, 2002).

15 See National Emission Standards for Hazardous Air Pollutants: Revisions of Area Source Category List under Sections 112(c)(3) and 112(k)(3)(B)(ii) of the Clean Air Act , 67 Fed. Reg. 43112 (June 26, 2002).

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and the implementing regulations set forth in 40 CFR Part 503 (Standards for the Use or Disposal of Sewage Sludge). Section 405(d) of the CWA requires EPA to establish numeric limits and mana gement practices that protect public health and the environment fr om the adverse effects of toxic pollutants in biosolids

. Section 405(e) of the CWA prohibits any person from disposing of biosolids from a POTW or other treatment works treating domestic sewage through an y use or disposal practice for which regulations have been established pursuant to Section 405, except as in compliance with the Part 503 regulations.

In the Part 503 regulations, U.S. EPA has identified the pollutants in biosolids that may adversely affect public health or the environment and has specified the management practices for the utilization and disposal of biosolids that are protective of pub lic health and the environment. For disposal by incineration, the Part 503 regulations require, am ong other requirements:

(i) numerous management practices and general requirements;

(ii) risk-based, site-specific limits for arsenic, cadmium, chromium, lead, and nickel
content in the biosolids incinerated;

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

(iv) operational emission limits for total hydr ocarbon (THC) or an alternative emission limit for carbon monoxide (CO); and

(v) monitoring, recordkeeping and reporting requirements.

See 40 CFR Part 503, Subpart E.

Furthermore, in the course of developing the Part 5 03 regulations, U.S. EPA also proposed to establish requirements for dioxins (including specific congen ers of dioxin, dibenzofuran, and coplanar PCBs). 16 However, after evaluating the emissions of dioxins from biosolids incineration, as we ll as surface disposal and land application, U.S. EPA decided su ch requirements were not warranted. 17 This decision was based on the results of a comprehensive risk assessment that demonstr ated that dioxin levels in biosolids and biosolids incinerator exhaust gases do not pose a signific ant risk to human health or the environment. 18

As explained in detail in NACW A’s 1997 comments (pages 15-17), the numeric emission limits and management practices requirements established under the Part 503 regulations were derived from years of study and evaluation of the po tential risks to human health and the environment which could be posed by the

16 See Standards for the Use or Disposal of Sewage Sludge: Proposed Rule , 64 Fed. Reg. 72045 (Dec. 23, 1999).

17 See Standards for the Use or Disposal of Sewage Sludge: Final Notice , 66 Fed. Reg. 66028 (Dec. 21, 2001).

18 See id.

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incineration of biosolids. The regu lation of SSIs under this existing regime are risk-based standards which were developed to protect human heal th and the environment from any reas onably anticipate d adverse effects from pollutants that may be present in biosolids. As a result, SSIs can clearly de monstrate that the emissions

from their units are not adversely impacting human health and the environment by demonstrating compliance with the Part 503 requirements. Moreover, the statutor y framework of this regime provides for ample means for U.S. EPA to identify and regulate additional concerns if supported by scientific evidence. For example, CWA Section 405 provides for a biennial review process th at was specifically established for identifying and regulating any additional pollutants of concern. U.S. EPA has repeatedly emphasized its confidence that the Part 503 regulations are adequately protecti ve of public health and the environment. 19

Additionally, since 1975, U.S. EPA has imposed NESHAPs for mercury and beryllium emissions which apply to certain SSIs. See 40 CFR Part 61, Subpart E and C. The mercury NESHAP applies, in relevant part, to any source that incinerates wastewater treatment plant sl udge and imposes emission limits for mercury, as well as imposes stack testing, sampling, and monitoring requirements. See 40 CFR Part 61, Subpart E. The beryllium NESHAP applies, in relevant part, to inci nerators which 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 th e 40 CFR Part 503 requirements for POTWs.

Since 1974, U.S. EPA has also im posed New Source Perfor mance Standards (NSPS) for SSIs under CAA
§ 111. See 40 CFR Part 60, Subpart O. These regulations appl y to any incinerator constructed or modified after June 11, 1973 that 1) combusts wastes containing more than 10% sludge (dry basis) produced by municipal sewage treatment plants; or 2) charges more than 1,000 kg (2,205 lbs.) per day municipal sewage sludge (dry basis). See 40 CFR § 160.150. Under the existing NSPS for SS Is, regulated incinerators must comply with emission limits for particulate matte r and opacity, as well as operationa l, monitoring, testing and reporting requirements.

Thus, of the eleven pollutants identified in CAA § 129, many are already directly regulated under Parts 503, 60, or 61, including total particulate matter, opacit y, lead, cadmium, mercury, and CO (optional, as a surrogate for THC). See CAA § 129(a)(4). Additionally, U.S. EPA and NACWA have both also determined that SSIs are only very minor sources of several other of the CAA § 129 pollutants, including dioxins, sulfur dioxide, and hydrogen chloride. NACWA’s March 17, 1997 comm ent letter (pages 13-14) documents in detail many specific examples of existing SSI regulations, or info rmation regarding emissions from SSIs, for each of the pollutants listed in Section 129.

In addition to the federal requirements applicable to SSIs outlined above, public agencies operating SSIs 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, through local regulatory authority, pretreatment standards to prevent discharge of pollutants to the PO TW that may pass through or interfere with treatment processes. Pretreatment is an effective way to reduce harmful constituents in the biosolids combusted by SSIs.

19 See Letter from James A. Hanlon, Director of U.S. EPA O ffice of Wastewater Management, to Greg Kester, State of Wisconsin Department of Environmental Resources, dated September 20, 2004 (“EPA believes that 40 CFR Part [503] regulations are protective of public health and the environmen t and we continue to support biosolids management in full compliance with the Part 503 regulation.”) (attached hereto as Attachment C).

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States also have authority to regulate and, in fact, do regulate air emissions from SSIs under their respective CAA State Implementation Plans. Together, these federa l, state, and local regulations form an existing and effective regulatory scheme for regula ting emissions from SSIs. Further re gulation of SSIs under Section 129 is not appropriate or necessary for the protecti on of public health and the environment.



### C. Regulation of SSIs under CAA § 1 29 Would Result in Prohibitive Costs and Only Negligible Beneficial Impacts.

U.S. EPA’s decision not to include SSIs among the cate gories of OSWI covered by the final OSWI rule is also supported by an analysis of co sts and benefits. The additional regulatory burdens imposed under CAA § 129 would be substantial to SSI operat ors, while offering no discernable corresponding benefits. The added costs then imposed upon POTW ratepayers would be considerable, and could potentially lead to the

elimination of incineration as a biosolid s management option for many communities.

Cost would invariably increase under CAA § 129 as SSI operators face competing MACT standards for pollutants that cannot be simult aneously 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 would be inconsiste nt with U.S. EPA’s declarations that incineration is a safe and acceptable biosolids disposal method. It would also be contrary to the congressional intent expressed in Section 405 of the CW A, in which Congress mand ates that U.S. EPA must provide for safe management practices for the use and di sposal of biosolids, and not to dictate “preferred” practices and eliminate others. For example, Section 405(e) of the CWA states that “[t]he determination of the manner of disposal or use of sludge is a local determination,” as long as the practice is in accordance with U.S. EPA’s regulations.

For all of these reasons, NACWA believes that U.S. EPA has prop erly interpreted CAA § 129, and reasonably exercised its discretion not to regula te SSIs as OSWIs pursuant to CAA § 129(a)(1)(E).



### 2. U.S. EPA Properly Determined that SSI s are Not “Solid Waste Incineration Units” and, Therefore, Are Not Subject to Regulation Under CAA § 129.

Section 129 of the CAA requires U.S. EPA to deve lop and adopt new source performance standards and emissions guidelines for “solid waste incineration units.” Therefore, the potential scope of incineration units covered by Section 129 is expr essly limited by the definition of “solid waste incineration units.” In CAA § 129(g)(1), Congress expressly defined this term to mean:

a distinct operating unit of any facility whic h combusts any solid waste material from any

commercial or industrial establishments or the general public (including single and multiple residences, hotels, and motels). . . .

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CAA § 129(g)(1). As fully explained below (as well as in NACWA’ s March 17, 1997 comment letter), biosolids generated by POTWs is not a “solid waste,” nor is it “from commercial or industrial establishments or the general public.” Simply stated, incinerators whic h combust biosolids from POTWs are not “solid waste incineration units” and do not fall within the scope of U.S. EPA’s duty to regulate pursuant to Section 129.



### A. Sewage Sludge Is Not from Commercial or Industrial Establishments or

the General Public.

As U.S. EPA has previously determ ined, SSIs are not subject to regula tion under CAA § 129 because the biosolids combusted by SSIs are generated at POTW s, rather than from “commercial or industrial establishments or the general public.” POTWs are not, contrary to the arguments advanced in petitioner’s request for reconsideration, properly characterized as “comm ercial or industrial establishments.” The fact that the sewered population served by a POTW is assessed a monetary rate for the collection and treatment services provided by the POTW does not transform it into a “commercial establishment” within the commonly understood meaning of that term, wh ich must presumably be the meanin g intended by Congress in CAA § 129(g)(1). Moreover, the fact that Congress and NACWA refe r to POTWs as “plants” or “facilities,” or that they refer to their works collectively as an “industry,” do es not transform POTWs into “industrial establishments” within any reasonable interpretation of the term.

Moreover, the careful phrasing employed by Congress in the definition of “s olid waste incineration

unit”—“solid waste material from commercial or industrial establishments or the general public (including single and multiple residences, hotels, and motels) ”—unambiguously indicates that not every category of incineration units is subject to regulation under CAA § 129. Indeed, if Congre ss had intended that incinerator units that burn solid

waste material from any source would be regulated by CAA § 129, it wo uld have simply stated that intention. In other words, Congress would not have added this second phrase which limits the scope of Section 129 to the specific waste sources of “commercial or industrial esta blishments or the general public.” The inclusion of such language by Congress was purposeful; CAA § 129(g)(1) cannot be read in such a manner that would render this limiting language meaningless.

Finally, while untreated domestic sewage may originat e at “commercial or industrial establishments or the general public,” it is not a solid waste when it co mes “from” these establishments. As discussed below,

untreated domestic sewage is expressly excluded from the definition of “solid waste.” Thus, under CAA § 129(g)(1), SSIs cannot be properly characteri zed as incinerating a solid waste coming from commercial or industrial establishments or the general public. Ev en if the CAA is deemed ambiguous on this point, Chevron
U.S.A., Inc. v. Natural Reso urce Defense Council, Inc ., 467 U.S. 837 (1984), directs that we defer to U.S. EPA’s reasonable interpretation of ambigu ous statutory terms. Certainly, U. S. EPA’s reading of the CAA § 129 as excluding SSIs from Section 129 because the biosolids th at they combust are genera ted at POTWs and do not

“come from” commercial or industrial establishments or the general public is a reasonable exercise of Agency

discretion.

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B. Sewage Sludge Is Not a Solid Waste.

While NACWA acknowledges that U.S. EPA has previo usly stated that it believes otherwise, NACWA respectfully maintains that the biosolids generated by POTWs and combusted in SSIs is not a “solid waste” for purposes of the definition of “solid waste incineration unit” provided in CAA § 129(g)(1). “Solid waste” is defined in Section 129 of the CAA by re ference to the definition of “solid waste” under the Solid Waste Disposal Act (which is generally referred to as the Resource Conservation and Recovery Act or “RCRA”). 20

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 ma terial, including solid, liquid, semisolid, or contained gaseous material resu lting from industrial, commerci al, mining, and agricultural operations, and from community activities, but does not include solid or dissolved material in domestic

sewage

. . .

RCRA § 1004(27) (emphasis added). Sewage sludge from PO TWs is exempt from the definition of “solid waste” as “solid or dissolved material in domestic sewage.” This exception is commonly referred to as the “Domestic Sewage Exclusion” under RCRA. In fact, both Congress and U.S. EPA have expressly interpreted the definition of “waste” under RCRA to exclude POTW sewage slud ge pursuant to the Dome stic Sewage Exclusion.

While the legislative history of Section 129 of the CAA is silent as to the defi nition of “solid waste” (other than, as discussed below, Co ngress was primarily concerned with municipal solid waste), the Domestic Sewage Exclusion had been written into RCRA for 25 years at the time Congress passed the 1990 CAA Amendment. Accordingly, in incorpor ating RCRA’s definition of “solid waste” in Section 129, Congress was well aware of the Domestic Sewage Exclusion enco mpassed in the definition of “solid waste.”

Moreover, shortly after Congress passed the 1990 CAA

, 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 revisi on), Senator Chafee clearly confirmed Congress’ understanding that the Domestic Sewage Exclusio n exempts POTW sludge from RCRA regulation:

Sewage treatment plants operated by local governments - 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 (September 23, 1992) (empha sis added). Accordingly, in using the limited definition of “solid waste” under RCRA for purposes of defining the scope of Sect ion 129, Congress was aware that POTW sewage sludge would be excluded from th e Section 129(g) definitions, which, in turn, would

20 CAA § 129(g)(6) (“The term ‘solid waste’ shall have the me aning established by the Administrator pursuant to the Solid Waste Disposal Act.”)

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August 14, 2006 Page 13 of 15

exclude regulation of SSIs under Section 129. Express exemption of SSIs under the de finition of “Solid Waste

Incineration Units” under Section 129 would have been redundant.

U.S. EPA has similarly interpreted th e scope of the Domestic Sewage Exclusion to include sewage sludge generated by POTWs. The clearest example of this exclusion of POTW sewage sludge from the definition of “solid waste” under RCRA is found in U.S. EPA’s promul gation of a rule to identify and list hazardous wastes for petroleum refinery process wastew aters. In the Preamble to the Final Rule (November 2, 1990), U.S. EPA concluded that POTW sewage sludge 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 treatment facilities on site at petroleum refineries as well as sludges generated at off-site wastewater treatment facilities. 14

. . .

14 It should be noted that if wastewater s generated at petroleum refineries are discharged to a POTW and 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.

55 Fed. Reg. 46354, 46364 (November 2, 1990) (emphasis added).

Accordingly both Congress and U.S. EPA interpret th e definition of “solid waste” under RCRA to exclude POTW sewage sludge pursuant to the Domestic Se wage Exclusion. Therefore, POTW sewage sludge is not “solid waste” as defined by RCRA, and incinerators which combust POTW sewage sludge do not qualify as

“solid waste incineration units” under Section 129.



### C. The Legislative History of CAA § 129 Further Indicates that SSIs Were Not Intended To Be Regulated as “Solid Waste Incineration Units.”

The legislative history of CAA § 129 is fully consistent with the conclusion that SSIs do not constitute solid waste incineration units. The provisions now co dified in Section 129 of th e CAA originated in a bill entitled “Municipal Waste Combustion Control Act of 1989,” introduced in Congress on January 25, 1989. The express purpose of the proposed legislation was to addres s the “garbage crisis” facing the nation in the late 1980s – “the unseemly aspects of the growing garbage cris is - garbage washing upon ocean beaches, a garbage barge sailing the Caribbean for weeks in search of a disposal facility.” 21

The bill further explained that Congress’ underlying objective was to “establish the needed regulatory program to make municipal waste incineration an environmentally sound part of our Nation’s waste

21 135 Cong. Rec. S289-01 (Jan. 25, 1989).

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management.” 22 While subsequent legislative history reveal s Congress’ concern with other specific, large

incinerators other than m unicipal waste combustors ( e.g. , medical waste incinerators and industrial incinerators burning waste paper, wood, yard wastes, food wastes, batteries and plasti cs), Congress did not once mention POTW sewage sludge or SSIs, or even hint that its concerns over the incineration of municipal solid waste extended to the incineration of sewage sludge.

In sum, Congress did not intend SSIs to be subjec t to Section 129 regulation. While Congress provided U.S. EPA with authority to identify ca tegories of OSWIs, it limited the sc ope of U.S. EPA’s authority in this regard to incinerators which combust “solid waste” as defined under RCRA and only solid waste “from commercial or industrial establishments or the general public.” SSIs do not fall within this definition, and therefore, cannot be regulated under Section 129 of the CA A. The plain language of Section 129, as further validated by the legislative history of CAA § 129, supports no other conclusion.



### CONCLUSION

NACWA strongly believes that U.S. EPA has reasonably determined that SSIs are not subject to regulation under CAA § 129 and has, a ccordingly, properly excluded them from the scope of the final OSWI rule. NACWA urges U.S. EPA to maintain its current dete rmination on this issue, an d thanks U.S. EPA for the opportunity to submit comments in support of the Agency’s position.

22 135 Cong. Rec. S556 (Jan. 3, 1989).

### NACWA’s Comments on EPA Reconsider a tio n of Sewag e Sludg e Inci neration
August 14, 2006 Page 15 of 15

If you have any questions or require additional in formation concerning NACW A’ s po si t i on on th is

issu e, p l ea se do not he sit a te to con t ac t Robe rt P. Dominak, Co-Chair o f NACWA Bio s olids Mana g e men t Committee, at 216-881-6 600, or Alexandra Dapolito Dunn, NA CWA G e neral Counsel, at 202-833-2672.

S i n c e r e l y ,

Ken Kirk

Executive Di rec t or

Attachmen t A: NACWA’ s March 17, 199 7 comments to U.S. EPA.

Att a chmen t B: Lett er fro m Benjamin H

. Grumble s , Acting As si s t ant A d mini str a tor of U. S. EPA, to Sc ott Hassett, S ecretary o f Wisconsin Departmen t of Na tural Resources d a ted October 7, 2004.

Attachmen t C: Letter fro m J a me s A. Hanlon, Director of U.S

. EPA O ffi ce o f Wa stewater Ma nagemen t
, to Greg Kester, State of Wisconsin Depart ment of Environment a l Resou r ce s d a ted September 2 0 , 2004.

# ATTACHMENT A

# ATTACHMENT B

# ATTACHMENT C