Air Quality Issues
EPA Evaluating Section 129 Rulemaking for Sewage Sludge Incinerators
Background: On January 14, 1997, EPA published a notice of additional information (NAI) under Section 129 of the Clean Air Act (CAA) establishing new source performance standards and emission guidelines for new and existing solid waste incineration units including units that incinerate municipal sewage sludge. Section 129 requires EPA to promulgate standards and guidelines, for new and existing sources, which include numerical emission limitations for the following substances: particulate matter, opacity, sulfur dioxide, hydrogen chloride, oxides of nitrogen, carbon monoxide, lead, cadmium, mercury, and dioxins and dibenzofurans. In addition, the standards and guidelines are to include requirements for emissions and parameter monitoring and provisions for operator training and certification. On March 17, 1997, AMSA submitted comments in opposition to EPA's Office of Air & Radiation proposal to subject SSIs to the same regulations as solid waste incinerators.
Status: AMSA has worked closely with EPA to consider AMSA=s opposition to regulate SSIs under Section 129. In response to the January 1997 NAI, EPA has gathered data on SSIs from the permit compliance system (PCS) database, information from the regions on Part 503 permits, and source test data from 97 incinerators. EPA and several AMSA representatives, visited several test sites in PA and NJ to assess various controls in place at both multiple hearth and fluidized bed incinerators. EPA stated that it will most likely use a technological approach to establish emission levels based on performance of the top 12 percent of control devices in place to determine the maximum achievable control technology (MACT) standard for SSIs under Section 129. EPA=s Offices of Air and Water held an internal meeting on March 18, 1998 to finalize plans for addressing SSIs. EPA requested the identity of several AMSA member agencies that submitted dioxin data as part of the 1994 Dioxin Assessment Peer Review. Those agencies were contacted and most have given the National Office permission to release their names to EPA. In April, 1998 EPA released the “Inventory of Sources of Dioxin in the United States.” To order a copy of this report, contact the ORD Publications Agency at 513/569-7562. EPA has hired Battelle and Pacific Environmental Services to conduct testing at three POTWs this summer to determine co-planar polychlorinated biphenyls(PCBs) emissions from biosolids incinerators. In addition, EPA and its contractors will conduct air emissions modeling to determine the impact of dioxin, dibenzofurans, and co-planar PCBs emissions from biosolids incinerators using a Most Exposed Individual scenario. Based on preliminary information collected by EPA, the Agency is uncertain whether emissions from SSIs warrant further control under Section 129. The Agency plans to announce its proposed strategy by November 1999. CONTACT: Mark Hoeke, AMSA 202/833-9106, or Gene Crumpler, EPA 919/541-0881.
EPA to Finalize POTW MACT Standard in October 1999
Background: On July 16, 1992, as required by the Clean Air Amendments of 1990, EPA published a list of industrial source categories that emit one or more of listed hazardous air pollutants. Listed industrial categories of "major" sources (those that have the potential to emit 10 tons/year or more of a listed pollutant or 25 tons/year or more of a combination of pollutants), EPA is required to develop standards for these sources that will require the application of stringent controls, known as maximum achievable control technology (MACT). The promulgation date for the MACT Standards was established for May 1999.
Status: The POTW MACT proposed rule was published in the December 1, 1998 Federal Register. In the notice, EPA did not propose any standards for existing POTWs or wastewater collection systems due to lack of data on the amount of HAPs resulting from these systems. New or reconstructed facilities that are major sources of HAPs would be subject to these standards, however. In addition, the proposed standards would require each new or existing POTW that treats specific industrial waste streams from an industrial user, for the purpose of allowing that industrial user to comply with another National Emission Standard for Hazardous Air Pollutants (NESHAP) to meet the treatment and control requirements of the relevant NESHAP. The proposal was distributed via ,IRegulatory Alert RA98-23; AMSA submitted comments to EPA by the January 15, 1999 deadline. AMSA's major recommendations focused on allowing models other than WATER8 be used to estimate air emissions, allow use of direct emissions testing in situations where models estimate a facility to be a major source, and allow 600/8000 series analytical methods for validation. The full text of AMSA's comments are posted on the Association's web page. Although the legal deadline for promulgating the final rule was set for May 15, 1999, EPA published a direct final rule in the April 16, 1999 Federal Register extending the date to October 15, 1999. CONTACT: Mark Hoeke, AMSA 202/833-9106, or Elaine Manning, EPA 919/541-5499.
EPA Finalizes Integrated Urban Air Toxics Strategy in Julyy
Background: EPA's draft Integrated Urban Air Toxics Strategy to comply with sections 112(k), 112 (c)(3), and 202 (1) of the Clean Air Act was released on September 14, 1998. The strategy outlines EPA's plans to address health impacts from both stationary and mobile sources in urban areas. The strategy includes a draft list of 33 hazardous air pollutants (HAPs) judged to pose the greatest potential threat to public health in the largest number of urban areas. Thirty of these HAPs are from 34 types of area sources, including publicly owned treatment works (POTWs). The strategy also includes a schedule for addressing remaining risks from air toxics by setting new standards for categories of small, stationary sources not targeted under the agency's existing air toxics program. These area sources would face new requirements for cutting air toxics by 2009, with some rules taking effect as early as 2005.
The new strategy may have an impact on POTWs. Area sources are small stationary sources of air toxics which emit less than 10 tons per year of any one HAP or less than 25 tons per year of a combination of HAPs. Area sources are not considered major under the Clean Air Act and not subject to existing maximum achievable control technology (MACT) standards under section 112 (d) of the statue. According to EPA, area sources account for 34 percent of air toxics emissions and mobile sources (cars, trucks, etc) account for 42 percent. Over the past five years, AMSA has been working closely with EPA to successfully demonstrate that POTWs are not major sources of HAP emissions (potential to emit 10 or more tons of any single HAP per year, or 25 or more tons per year of any combination of HAPs). AMSA submitted comments on November 30, 1998 outlining three points. Firstly, many of the goals and objectives of the draft strategy could be addressed concurrently while EPA is working on the 112(d) POTW MACT standards. Second, the proposed additional regulation must be based on updated data, and finally, that insufficient attention is being focused on mobile sources and real time monitoring.
Status: EPA released its final Integrated Urban Air Toxics Strategy on July 6, 1999. The strategy identifies a list of 33 HAPs judged to pose the greatest potential threat to public health in the largest urban areas. Thirty of these HAPs are from 29 types of area sources, including POTWs. The Strategy by itself does not automatically result in regulation or control of emissions. The strategy outlines actions to reduce emissions of air toxics and to improve EPA=s understanding of the health risks posed by air toxics in urban areas. Many of the activities identified in the Strategy will require public notice and comment. EPA has indicated that it will work with a number of stakeholder groups such as AMSA later this year to develop national assessments of the risks from air toxics and the materials to communicate the findings to the public. CONTACT: Mark Hoeke, AMSA 202/833-9106.
EPA Developing MACT Standards for Combustion Devices
Background: EPA is developing National Emission Standards for Hazardous Air Pollutants (NESHAP) and New Source Performance Standards (NSPS) for certain combustion sources under the Industrial Combustion Coordinated Rulemaking (ICCR) process using an advisory committee consisting of a Coordinating Committee and various workgroups. The ICCR process includes several types of combustion devices operated by AMSA members which utilize digester gas including boilers, Reciprocating Internal Combustion Engines (RICES), Combustion Turbines (CTs), and very likely waste gas flares (under the heading of incineration). Members of AMSA's Air Quality Committee are represented on the Coordinating Committee and work groups for boilers, RICES, CTs, incinerators and the source testing workgroup.
Status: In the summer of 1997, EPA conducted a limited data gathering survey to support development of regulations for the combustion devices. Due to concerns that the combustion devices operating at POTWs will be considered with all similar combustion categories, AMSA conducted a survey of the membership to collect both data inventory and emission data for combustion devices. A major concern was that combustion control devices applicable for burning of natural gas may get applied to the combustion of digester gas, which past experience at several POTWs has shown to be either technically infeasible or not cost-effective. The survey results, which were submitted to EPA in late September 1997 indicated that very few AMSA member agencies have conducted emissions testing for hazardous air pollutants (HAPs) and criteria pollutants. The FACA was discontinued after September 20, 1998. Studies are currently being conducted to evaluate, test, and compare formaldehyde emissions from several classes of engines burning digester gas using the Fourier Transform Infrared (FTIR) spectroscopy and dinitrophenyl hydrazine methods to determine if a follow up survey of the membership is warranted. Preliminary data indicate that several orders of magnitude of formaldehyde emissions from digester fired engines may result using this new method that was developed for natural gas fired engines. An unsolicited proposal was submitted to WERF to assess validation of the FTIR method for digester versus natural gas fired engines. This activity is closely linked with EPA's ICCR initiative which will develop proposed MACT standards by November 15, 1999 on a variety of combustion sources such as wastewater boilers, gas turbines, reciprocating engines, and flares. CONTACT: Mark Hoeke, AMSA 202/833-9106.