453N89007 NATIONAL AIR TOXICS INFORMATION CLEARINGHOUSE NEWSLETTER ^ EDA 0ffice °'Air Quality Planning and Standards July 1989 OCHH Research Triangle Park, North Carolina 27711 rD)r°)/A\ fJ /i\n state and Territorial Air Pollution Program Administrators U/rAlj^LrA-a II Z-ALL=iZr--ALn Association of Local Air Pollution Control Officials IN THIS ISSUE NATICH PROVES USEFUL IN COLLECTING CHEMICAL AND SITE DATA 1 STATE/LOCAL AGENCY SPOTLIGHT: VERMONT REVISES RULE ON THE CONTROL OF HAZARDOUS AIR CONTAMINANTS 3 PIPQUIC SYSTEM USED IN URBAN AIR TOXICS ASSESSMENT 4 NEW JERSEY PATTERNS AIR TOXICS PROGRAM ON ITS CRITERIA POLLUTANT PROGRAM ... 6 REVISIONS PROPOSED TO THE SUPERFUND HAZARD RANKING SYSTEM FOR THE AIR PATHWAY 7 THE PHILADELPHIA AIR TOXICS PROGRAM OUTLINES ITS DEVELOPMENT, PROGRESS 8 OAQPS STANDARDS TO CONTROL AIR EMISSIONS FROM HAZARDOUS WASTE TSDF 9 FIRST FIVE TOXICOLOGY PROFILES NOW AVAILABLE 10 VERMONT REGULATION COVERS CFCs, MOTOR VEHICLE AIR CONDITIONING 11 AIR RISC WORKSHOPS ATTRACTED PARTICIPANTS FROM ACROSS THE UNITED STATES 11 NATICH PROVES USEFUL IN COLLECTING .. wxit. CHEMICAL AND SITE DATA The many options available in NATICH can sometimes lead to uncertainty about which menu selec- tions will give the user desired results. This article is designed to walk the user through a NATICH data base search, highlighting menu choices likely to provide in- formation of value for collecting chemical- and site- specific data. There are three options in the initial Clear- inghouse Reports menu that should be particularly useful in this regard. All are outlined in a flow diagram (Figure 1). The first option is agency reports, the second is pollutant reports and the third is risk analysis reports. Selecting the agency reports options invokes the agency reports menu. To access the appropriate infor- mation there are four options to consider. 1. Acceptable Ambient Concentration Guidelines or Standards (Option 3). 2. Permitting (Option 7). 3. Ambient Monitoring (Option 9). 4. Emissions Inventory (Option 10). Choosing Options 3,7 or 9 prompts users to indicate the State for which they would like information. Within any State, they must then indicate which agency is of interest. Option 3: Acceptable Ambient Concentration Guidelines or Standards. The user enters the desired agency and is supplied with a regulatory contact name and telephone number, a list of all the pollutants reported by that agency with acceptable ambient concentration guidelines or standards, and information such as the Chemical Abstracts Services (CAS) registry number, the ambient concentration and the averaging time. Option 7: Permitting Information by Agency. The user chooses the desired agency and a list of permits is displayed with information on the Standard Industrial Classification (SIC) code of the permitted source, along with year of issue, permit identification number, type of control equipment and pollutant(s). Option 9: Ambient Monitoring Information by AUG 7 1989 ------- Agency. The resultant display includes a contact name with telephone number and a list of pollutants reported by the Agency. Each of these pollutants can be screened individually and information is then available on the location of the monitoring, the year measured, the sampling technique and the analytical method. Option 10: Emissions Inventory Information by Agency. Choosing Option 10 presents the user with three choices: viewing air toxics emission inventory informa- tion, viewing emissions inventory characteristics or view- ing inventory data for a specific agency. With either the first or the second options, information is organized in a yes/no question and answer format for issues such as: How often is the inventory updated? Does the inventory cover primarily larger point sources? How many pollutants and sources are included in the inventory? The second option allows the user to select a subset of questions with a given yes or no response and choose a list of emissions inventories (listed by State, Agency, contact name and telephone number) that meets all the selection criteria. The third predefined option provides a list of all pollutants, CAS numbers, emission rates and locations for an entered State and control agency. The second option in the Clearinghouse Report menu that is of particular use when searching for infor- mation on pollutants and locations is Pollutant Reports. Choosing Acceptable Ambient Concentration Guidelines or Standards when in Pollutant Reports per- mits the user to enter a pollutant by name or CAS number. Information is then displayed for agencies that have reported acceptable ambient concentrations along with the concentration, the averaging time and comments. The final option, which provides data on risk assessments completed by EPA, is Risk Analysis Reports. The user can enter a desired State and the resultant data set includes pollutants, facility names, city or county, SIC code, total emissions, maximum in- dividual risk, annual incidence estimates and date entered. The user can also select a pollutant that results in a display of the parameters listed above, and also in- cludes all sites analyzed in the United States. An addi- tional option, although not yet available, will allow NATICH users to access SARA Title III data directly. This option is expected to be ready by the end of this year. Although this description of accessing NATICH for data on pollutants to compare to emissions or ambient concentrations derived from other information sources is not exhaustive, it should allow the user to develop a basic understanding of NATICH capabilities and the data base contents. Option 1 Agency Reports (#1) Figure 1. Option 1 - Acceptable Am- bient Concentration Guide- lines or Standards (#3) Select State Select Agency Option 2 Permitting (#7) Select State Option 3 Ambient Monitoring (#9) Select State Option 4 Emissions Inventory (#10) Inventory Data for a Special Report Emissions Inventory Characteristics Option 2 Pollutant Reports (#2) Acceptable Ambient Concentration (#2) Select Pollutant Name or CAS No. Option 3 Risk Analysis Reports (#5) Select Pollutant Select State Select Agency — Select Agency Air Toxics Emissions Inventory Information 2 ------- STATE/LOCAL AGENCY SPOTLIGHT: VERMONT REVISES RULE ON THE CONTROL OF HAZARDOUS AIR CONTAMINANTS by Brian J. Fitzgerald, Special Studies Engineer, Vermont Agency of Natural Resources Vermont's original regulatory requirements for potentially hazardous air contaminants were a subset of the particulate control regulation. In 1981, Vermont amended its regulations to define the term "hazardous air contaminant" and to provide a methodology for the review of sources that emit these contaminants. The review and analysis of these sources was done on a case-by-case basis. The approach was very costly for both the Vermont Agency of Natural Resources (ANR) and the source under review. The approach also resulted in the public's perception of unequal application of re- quirements from source to source. Therefore, the Vermont ANR proposed to amend the regulation to pro- vide additional clarity and specificity to the review pro- cess. The following article highlights Vermont's ex- perience in drafting the regulation as well as the contents of the regulation itself. Vermont Sought Public Involvement Trying to define a workable set of air toxic regula- tions that effectively protects the public health was dif- ficult. However, the Vermont ANR actively sought in- dustry and environmental group involvement early in the revision process. Without these groups' involvement and consensus, public endorsement of any revision would have been difficult to achieve. The Vermont ANR held a series of meetings with representatives of these groups to understand the issues of most concern to their constituents. The meetings ranged from broad philosophical discussions of the terms "safe" and "acceptable" when applied to air tox- ics and human health, to more focused discussions on the appropriateness of classifying a specific chemical as hazardous. Rule 5-261 Outlined Vermont's revised rule governing the control of hazardous air contaminants (Vermont Air Pollution Con- trol Regulation 5-261) became effective on March 4, 1989. The revised regulation establishes, among other things, a three-part review process which includes: (1) the identification and quantification of chemicals re- leased from sources of toxic pollutants, (2) the control and reduction of releases that are above specified threshold values, and (3) a demonstration that the release will not cause levels of the contaminants to ex- ceed specified concentrations in the general outdoor air. Under the new rule, Vermont ANR has adopted a specific list of approximately 200 chemicals that are expected to be most frequently encountered during the review process. However, this is not an all-inclusive list in that it does not contain all the pollutants the ANR would consider hazardous. Any chemical released into the atmosphere by a source, whether or not it appears on the list, may be subject to the new rule if it is deter- mined by the ANR to be a hazardous air contaminant. The list of hazardous air contaminants identified in the new rule is further divided into categories that repre- sent the severity of the health effect associated with that contaminant. The three categories in order of severity are (1) compounds known or suspected to cause cancer, (2) compounds which produce irreversible, chronic health effects, and (3) compounds that cause mainly short-term, reversible health effects. Using these categories enables the ANR to apply different assess- ment methods and adjustment factors depending on the most severe health effect end point expected. Each contaminant listed has associated with it an Action Level (AL), expressed as an emission rate, and a Hazard Limiting Value (HLV), expressed as an ambient concentration. Action Levels represent an emission rate threshold; below the given AL, the ANR considers the release insignificant for that contaminant. The use of emission thresholds provides a means for the ANR to focus its resources on larger, more significant releases. HLVs represent an ambient air concentration threshold; below the given concentration, the ANR believes human exposure to that contaminant would not be anticipated to result in an increase in mortality or serious irreversi- ble or incapacitating reversible illness. How the Rule Is Applied Both new and existing air contaminant sources are subject to the revised regulation. Sources will be evaluated for emissions of all hazardous air con- taminants, including, but not limited to, the contaminants identified in the regulation. The ANR's emphasis at this stage is an accurate quantification of toxic emissions. For new sources, documentation must be presented that ful- ly identifies and quantifies all expected air emissions. For each substance discharged, the source must quantify its maximum proposed emissions. If emission rates can- not be accurately projected, the source may be required to conduct test burns or trial runs, including emission testing, prior to the start of normal operations. Emission rates for existing sources will be based on actual emissions during source operations. These will be used to determine the appropriate level of review for the source. A source whose total emissions from all emission 3 ------- points are less than the AL for each contaminant is con- sidered insignificant by the ANR and no further review of the source is necessary. However, once a source has been identified as a significant emitter, that is, exceeding an AL, then emissions reduction must be considered. The source is then required to apply air pollution control technology or other emission reduction tech- niques adequate to attain the lowest emission rate achieved in practice for similar sources [Hazardous Most Stringent Emission Rate (HMSER)]. Once HMSER has been determined and documented in a permit (new or modified source) or enforcement document (existing source), such determination will remain in effect for five years. The resulting emission rate, after achieving HMSER, is compared to the AL for the contaminant(s) under review. If the emission rate is less than the AL, no further analysis is required. If, after HMSER is implemented, the emission rate is still greater than the AL for any contaminant, or if the source cannot achieve HMSER due to economic im- pacts, the ANR may require an air quality impact evalua- tion. Such an evaluation must demonstrate that the emissions from the source will not cause or contribute to an exceedance of an HLV. If, after applying HMSER and performing an air quality impact analysis, a source would still cause or con- tribute to an exceedance of an HLV, then the source would be denied permission to operate (new/modified source) or would be considered in violation of the regula- tion (existing source). Under Vermont's Air Pollution Control Regulations, such a source may request a variance from this rule. If a variance is requested, the source is required to notify in writing, at the time of the variance request, all persons and towns significantly affected by the source. The Vermont ANR is now directing its efforts in air toxics toward implementing the revised regulation. Work groups are being established with industry to assist in the understanding of the rule and to give advice on how to achieve compliance. Information for permit applicants is also being compiled to assist potential new sources. For further information on the Vermont Air Toxics Program, contact Brian Fitzgerald, Special Studies Engineer, or Harold Garabedian, Acting Director, Vermont Agency of Natural Resources, Air Pollution Control Division, Waterbury, Vermont, (802)244-8731. PIPQUIC SYSTEM USED IN URBAN AIR TOXICS ASSES'. Several years ago, EPA's Office of Policy, Planning and Evaluation (OPPE) developed a data handling system called Program Integration Project Queries Using Interactive Commands (PIPQUIC) for conducting multimedia "geographic studies" of toxic pollutants. Under its National Air Toxics Strategy, EPA has en- couraged State and local agencies to assess their urban air toxics problems and evaluate various mitigation alter- natives. Since urban risk assessments involving multi- ple source, multiple pollutant exposures are new to most State and local agencies, EPA's Office of Air Quality Planning and Standards is evaluating PIPQUIC as a tool for conducting these assessments using air toxics emis- sions data. The PIPQUIC has been a useful tool in a number of completed assessments. The OPPE initially used it in geographic studies in Philadelphia, Baltimore, Kanawha Valley and Santa Clara Valley. Region V used it in its recent study in Southeast Chicago* Region V is using PIPQUIC in two ongoing studies of air toxics ex- posures and deposition in and around Lake Michigan and the Detroit area. Maryland anticipates using PIPQUIC in a study of air toxics and ozone/carbon monoxide co-control opportunities in Baltimore. Minnesota is planning to use PIPQUIC in an urban air toxics assessment of Minneapolis and St. Paul. The EPA's Office of Toxics Substances (CFTS) is evaluating the utility of using PIPQUIC for storing, organizing and tMENTS displaying SARA 313 toxic release inventory data. The PIPQUIC is available on EPA's IBM 3090 at Research Triangle Park, North Carolina, and is accessi- ble to account holders through any dialup terminal, in- cluding desktop PCs using terminal emulator software. The PIPQUIC offers a "toolkit" to produce bar charts, tables, printouts, pie charts, area maps, 3-D maps, tables and spreadsheets. It also creates charts, maps, tables using user-supplied emissions and release data for point and area sources. Using emissions, population and meteorological data supplied by the user, PIPQUIC executes two EPA dispersion models, Industrial Source Complex, Long- Term (ISCLT) and Climatological Dispersion Model (CDM), to generate estimates of ambient concentrations of air toxics across a user-defined grid. Alternatively, the user can execute models of his choice external to PIPQUIC and then enter the resulting source/receptor relationships into PIPQUIC. In either case, PIPQUIC ap- plies the resulting model-predicted ambient concentra- tions to grid cell-resolved population data to estimate ex- posures. These exposure estimates are then applied to cancer unit risk factors to calculate individual cancer risks and population incidence for each grid cell and for the entire modeling grid. Typical grid cell sizes in PIPQUIC applications have ranged from 1 to 5 km on each side. The PIPQUIC does not estimate maximum individual concentrations around specific facilities. 4 ------- PIPQUIC Provides Broad Graphics Capabilities The PIPQUIC allows the user to display emissions, exposure, and risks in a number of ways through the use of its graphics toolkit. For example, Tool 450 creates a broad range of study area maps, allowing the user to overlay point sources, modeling grids and area source emissions on these maps. Tool 440 allows the user to rank order his source and emissions data in many ways via bar charts, cross-tabulations, pie charts and print- outs. Tool 453 allows the user to identify hotspots, in- dividual risks and aggregate incidence, and to assess the impact of each pollutant and source at any receptor within the study area. Example graphs generated using Tools 440 and 453 are shown in Figures 1 and 2. Others include Tool 1-2-3 for downloading source, emissions and cancer incidence data in spreadsheet format for simple control strategy evaluation. The PIPQUIC also enables the user to download maps, graphs and tables created on the IBM mainframe to his desktop computer. Then, using various inexpensive software packages, the user can edit, make slides and color plots, as well as assemble video presentations. State and local air agencies who want more infor- mation on PIPQUIC may contact Tom Lahre, MD-15, En- vironmental Protection Agency, Research Triangle Park, North Carolina 27711, or call him at (919) 541-5668, (FTS) 629-5668. A brochure, demonstration diskette and user's guide are available free to air agencies. *See March 1989 issue. Figure 1. Example of Source Contributions (metric tons per year) to Total Emissions for Select Pollutants Using Tool 440. COMPOUND GAS VAPORS PEBCHLOROETHYLENE TOLUENE METHYLENE CHLORIDE ALL OTHER BENZENE TRICHLOROETHYLENE POLYC ORG MATTER 1. 3-BUTADIENE FORMALDEHYDE STYRENE V//NM & 0.00 ]—i—i—i—i—i—r 5000.00 MTY SUM -i—i—i—|—i—r 10000.00 11 1 I 15000.00 MTY SUM 14691.74 8124.26 7450.61 5724.64 4829.00 3245.31 2185.31 1757.39 1734.65 1377.22 1159.18 SOURCE [22 AGRICULTURE BURN Y7 HEATING ¦ SOLVENT USAGE COOLING TOWERS Q POINT SOURCES | | VOLAT IZ / P0TWS GAS MARKETING R0A0 VEHICLES KJ WASTE OIL BURN 5 ------- Figure 2. Example of an Analysis of Modeling Results for Acetone (ug/m1), All Sources, Using Tool 453. CONCENTHN 1 1 . SB 7 .96 4 . 03 0.10 5B4.000 572.000 2308 000 566.000 NEW JERSEY PATTERNS AIR TOXICS PROGRAM ON ITS CRITERIA POLLUTANT PROGRAM by Joann Held, Acting Chief, Bureau of Air Quality Planning and Evaluation New Jersey has developed its air toxics program from the State's existing criteria pollutant program. As with the criteria pollutants, the cornerstone of New Jersey's air toxics program is the state-of-the-art control requirement for new and modified sources. The authority to require such controls comes from the air program's enabling legislation [N.J.S.A. 26:2C-9.2(c)]. It is also in- corporated into the rule on Permits and Certificates [N.J.A.C. 7:27-8.5(b)]. This authority provides the latitude to regulate many pollutants, and to set as a goal ambient air of the highest purity achievable by the installation, operation and maintenance of pollution control devices and methods consistent with the application of the most advanced controls [N.J.A.C. 7:27-13.2(a)] for new and modified sources. In December 1979, the New Jersey Department of Environmental Protection (DEP) began to include ex- isting sources in its air toxics program by adopting a regulation (N.J.A.C. 7:27-17) that required all sources of 11 toxic volatile organic substance (TVOS) emissions to register with DEP and demonstrate that they were us- ing state-of-the-art air pollution controls. The 11 TVOS pollutants listed in Table 1 were chosen on the basis of volatility, carcinogenicity, and national production. Periodic expansion of this list is planned in order to bring additional existing sources into the program. By the mid-1980s, DEP recognized that one short- coming of the control technology approach was that it did not guarantee that the emissions from a source with state-of-the-art controls were actually safe. Therefore, for incinerators, resource recovery facilities, and other potential sources of toxic emissions, the risk associated with the residual emissions (i.e., the risk that remains after control technology has been applied) is now routinely examined. In this way, risk assessment is used as a tool to adjust the determination of state-of-the-art controls for toxic emissions. Thus far, risk assessment has been applied only to carcinogens, although expan- sion to noncarcinogens is being investigated. 6 ------- tOTIOOL UB TOXICS mOMIIGI CfflBINGKXBI OSOKt CUD The EPA is interested in receiving jour feedback on the usefulness of current Clearinghouse activities (i.e., newsletters, conputerized data base, special reports, and other publications). In addition, we-would also like an; suggestions you have on Nays to iaprove and/or the Clearinghouse in order to better net the needs of our user cmnity. This "Report Card" provides quick, yet very useful, feedback for EPA and STAPPA/ALAPCO in planning for future Clearinghouse efforts. Please take a aonnt to answer the questions below about the Clearinghoise. After collating this "Report Card," please fold, staple, affix postage, and aall. Your feedback is greatly appreciated. National Air Toxics infomtlon Clearinghouse Data Baa* (RIIICE) 1. Do you access the HATICH data base on-line? Yes No 2. If yes, how often do you access the data base on-line? 3. If no, do you have access to a personal coqrater and aodestf Yes No 4. Have you had problev obtaining an account? Yes No 5. Have you had log on problns? Yes No Conents 6. How often should the data In the data base lie ifdated? 7. Do you find the data base useful? Yes No Clearingtouee Publications 1. Do J8u think the bi-mathly newsletter publication schedule is adequate? Yes No 2. If no, what frequency would you prefer? 3. Annually, the Clearinghouse publishes hard copy reports of information sutaitted by State and local agencies attained In NATICH. Bow would you rate this report on a scale of 1 to 10, where 10 > very useful and 1 » not useful? Rating: Conents: 4. Is publication of the bibliography and ongoing research also useful to you? Yes No 5. Sow often should these be published (annually or every two years)? Special Reports 1. Do you find the special reports (such as "Qualitative and Quantitative Carcinogenic Risk Assessmt") that are published periodically to be useful? (Rate on a scale of l to 5, with 5 being very useful, and 1 not useful at all.) Rating 2. Should NATICH continue to ptfcllsh these special reports? Yes No 3. Do you have an idea for a special report? Yes No Caswit General 1. Have you used the NATICH help line? Y« No Hon would you rate the hslp you received? Good Satisfactory Unsatisfactory What could lie done to i^rove the response efficiency? Consent — 2. Mat would be the eost helpful activity that the Clearinghouse could do for you?, Haaa/Ptooe (optional): Specs is provided on the reverse side for additional ooeewti or suggestions you have on either future topics to be covered In the Clearinghouse prtlicatlons or infonatlon contained in NATICI. Additional Caasnts/Sujgestlons: 3. Km wold you describe your organlutlon? state Agency other Federal Agency local Agency Industry U.S. EPA Consultant Enviromntal/Special Interest Group University other. ------- Fold here/Stamp/then Staple or Tape on Selvage PLACE STAMP HERE Scott Voorhees U.S. Environmental Protection Agency MD-13 Research Triangle Park, NC 27709 ------- Risk Management Alms For Negligible Incremental Risk While risk assessment is primarily a scientific endeavor, risk management is highly dependent on cultural and economic factors. In the air program, risk assessment and risk management functions are per- formed by two different groups in order to separate the analytical and management aspects of risk. The goal of managing the emissions of carcinogens is a negligible incremental cancer risk. In view of the uncertainty involved, cancer risk assessment is not used as an ab- solute determination of unacceptability, except perhaps in the case of very high risk such as a lifetime incre- mental individual risk greater than 1 in 10,000. Risks less than 1 in 1,000,000 (after controls) are generally con- sidered negligible, and risks between 1 in 1,000,000 and 1 in 10,000 are considered on a case-by-case basis. Air Toxics Steering Committee Plans, Sets Goals Since the air toxics program evolved from the criteria pollutant program, air toxics responsibilities have simply been added to the routine criteria pollutant ac- tivities of permit evaluators, enforcement officers, and ambient monitoring and stack testing personnel. This permitted the program to start quickly since it did not re- quire any special requests for new resources. The disad- vantage of such a decentralized program, however, is that it requires enormous cooperation and coordination between bureaus in an air pollution control program that now includes about 170 employees. Also, without a cen- tral planning group, it was difficult to establish priorities and make decisions regarding the next steps to take in the development of the program. Therefore, an Air Toxics Steering Committee was established in late 1987 to act as a focal point for plan- ning and to ensure adequate cooperation within the air toxics program. The committee's seven members repre- sent each of the groups in the air pollution control pro- gram that are actively involved in air toxics. They propose goals and objectives for the air toxics program. Most of the short-term goals of the Committee con- cern gathering data to establish priorities and set new directions for the air toxics program. A current project is developing an air toxics emissions inventory separate from the data base of permit information compiled for the criteria pollutant program. A major effort to monitor the air toxic concentrations in the New York Metropolitan Area (centered on Staten Island) is underway in coopera- tion with the New York Department of Environmental Conservation and EPA. In addition, SARA 313 emissions information is being scrutinized to identify the pollutants and source categories that should be of greatest concern in New Jersey. For further information about New Jersey's Air Toxics Program, contact Joann Held at (609) 292-6722. TABLE 1. LIST OF TOXIC VOLATILE ORGANIC SUBSTANCES Benzene Carbon tetrachloride Chloroform Oioxane Ethylenimine Ethylene dibromide Ethylene dichloride 1,1,2,2-Tetrachloroethane Tetrachloroethylene 1,1,2-Trichloroethane Trichloroethylene REVISIONS PROPOSED TO THE SUPERFUND HAZARD RANKING SYSTEM FOR THE AIR PATHWAY In response to the requirements of the Superfund Amendments and Reauthorization Act of 1986 (SARA), revisions to the Hazard Ranking System (HRS) were pro- posed in the Federal Register on December 23,1988 (53 FR 51962). The HRS is a scoring system used in the Superfund program to assess the relative threat associated with actual or potential releases of hazardous substances from a site. It aids in determining whether specific sites warrant listing on the National Priorities List (NPL), thus making them eligible for further investiga- tion and possible cleanup. The revisions were developed following extensive review by the Science Advisory Board, an EPA-wide work group, as well as the Office of Management and Budget. If adopted, they would significantly change the way the HRS evaluates air releases from hazardous waste sites. The current HRS was developed in 1982 and has been used to place 1,175 sites on the NPL. Some 378 sites remain in proposed status. How the Current HRS Works At present, the HRS score is calculated by estimating risks presented in three potential "pathways" of human or environmental exposure: ground water, sur- face water, and air. Within each pathway of exposure, the HRS considers two primary factors: the likelihood of ex- posure to a hazardous substance through a release and the magnitude or degree of harm from such exposure. The resultant HRS score therefore represents an estimate of the relative "probability and magnitude of 7 ------- harm to the human population or sensitive environment from exposure to hazardous substances as a result of the contamination of ground water, surface water, or air" (47 FR 31180, July 16, 1982). Sites receive scores ranging from 0 to 100, with sites scoring 28.50 or greater being eligible for the NPL. The air pathway is scored only if documented monitoring results show evidence of a release from a site; otherwise, the air pathway score is zero. Because air releases are often episodic and difficult to detect, the number of sites placed on the NPL due to air releases has been limited. What SARA Requires SARA requires that EPA modify the HRS to assure "to the maximum extent feasible, that the hazard rank- ing system accurately assesses the relative degree of risk to human health and the environment posed by sites and facilities subject to review." One of SARA's specific requirements mandates EPA to consider "the con- tamination or potential contamination of the ambient air which is associated with a release or threatened release" as a criterion for listing sites. In addition, EPA has been guided by SARA's legislative history. The HRS revisions are intended to ensure that the system per- forms accurately and efficiently in identifying candidates for response actions. The Agency's goal in revising the HRS is to balance the cost of gathering data for the HRS against the increased accuracy gained from these ad- ditional data. How the Air Pathway Will Be Revised An early step in assessing options for revisions to the HRS was to review the current HRS and evaluate it in light of existing screening approaches used to assess air releases. The EPA is proposing to retain the current factor value approach, which considers parameters modified by weighting factors that are derived from analytical models and site characteristics. Such parameters include population distribution, site size, and meteorologic conditions, among others. However, both the parameters and the weighting factors have been revised and new ones have been added. The proposed changes to the air pathway include: - Adding a mechanism to consider potential air releases. This mechanism evaluates the mobili- ty of the substances at a site, the types of sources, and the source containment. - Weighting the impact on the target population depending on their distance from a site. (This reflects the diminishing risk as a function of in- creasing distance.) - Evaluating the maximally exposed individual. To evaluate the effect air releases at hazardous waste sites have on the neighboring population, EPA's Office of Solid Waste and Emergency Response (OSWER) used the Human Exposure Model (HEM), the screening model routinely employed by the Office of Air Quality Planning and Standards (OAQPS) to assess risks posed by air toxics. The OSWER estimated the necessary source terms using OAQPS emissions work for Resource Conservation and Recovery Act Treatment, Storage, and Disposal Facilities. The results of these analyses provided information on the range of risks due to air emissions found at varying distances from Super- fund sites. In the revisions to the air pathway, EPA's Science Advisory Board focused on the distance weighting scheme and reviewed OSWER's analyses. They recom- mended a scheme that would account for the differences in concentrations at different distances from a site. These recommendations have been incorporated into the proposed revisions to the HRS air pathway. Additional revisions to the HRS that would affect the air pathway include: - changes in the way toxicity is calculated, - modification to the calculation of waste quantity, and - revisions to the areas evaluated for sensitive environments. The proposed HRS revisions would also include a fourth pathway, the on-site exposure pathway, which would consider risks to direct contact with hazardous wastes or contaminated soil. This new pathway will cap- ture some of the risks associated with air releases. More specifically, it would explicitly address soil contamina- tion and reflect risks associated with reentrainment of dust. The EPA closed the public comment period on the proposed revisions to the HRS on March 23,1989. The revisions are expected to be final in early 1990. For fur- ther information, call Jane Metcalfe or Larry Zaragoza, Office of Emergency and Remedial Response, at (202) 382-6357. THE PHILADELPHIA AIR TOXICS PROGRAM OUTLINES ITS DEVELOPMENT, PROGRESS by Nick Clclrettl, Assistant Chief, Hazardous Air Pollutants Air Management Services, Department of Public Health, City of Philadelphia Air Management Services (AMS), the air pollution air toxics program in place since 1981. It was, in fact, the control agency for the City of Philadelphia, has had an first local program in the country. This article will explore 8 ------- some of the program's key elements. Air Management Regulation VI, Control of Emis- sions of Toxic Air Contaminants (pursuant to the Philadelphia code, Title 3-300), became effective August 7,1981. Basically, a "right-to-know" regulation, it lists 99 individual compounds or classes of compounds con- sidered to be toxic air contaminants. Listed pollutants are substances of concern due to their chronic human health effects (mainly carcinogenesis) that are likely to be found as air contaminants (for example, benzene but not saccharin). Emitters are required to report maximum emissions of all listed pollutants to AMS for both new and existing sources along with the corresponding material safety data sheets (MSDS). These maximum emissions then become a part of operating license conditions. While there is no established de minimis level for reporting quantities, there is a practical lower limit in that the regulation does not outline specific means that must be taken to quantify emissions. Furthermore, there are categorical reporting exemptions for commercial fuel combustion sources, retail dry cleaners, retail and non- commercial storage and handling of motor fuels, in- cineration of non-by-product industrial waste, and in- cidental or minor sources. Air Management Services is required to evaluate the reported emissions to determine if those discharges pose a health hazard. In support of that function, AMS convened an advisory committee composed of experts in the fields of toxicology, industrial hygiene, and occupa- tional medicine. The committee, with support from AMS, developed a protocol for reviewing existing toxicologic data (e.g., human epidemiologic studies, occupational exposure guidelines or standards, and animal car- cinogen studies). Following data review, the "best" or most appropriate data were used to establish ambient air quality guidelines (AAQGs). AAQGs represent accep- table risk levels to which the public may be exposed. The committee's deliberations took two and one-half years. Using these guidelines, AMS evaluated the health hazard potentials of the reported emissions. AMS engineers spent more than a year verifying some 700 submissions. Once verified, the significant sources were evaluated by a screening model (a conservative simplification of the Industrial Source Complex Long- Term Model (ISCLT)), which predicted maximum annual average ground level concentrations. To date, no ex- ceedances have been found. This evaluation procedure has now been incorporated into the agency's new source review process. As a result, in several cases permit ap- proval has been delayed pending the addition of further controls. AMS has developed a sophisticated analytical capability for air toxics and implemented a toxics air monitoring program in November 1985. There have been as many as three separate sites being monitored on a 24-hour basis once every 6 days for chloroform, carbon tetrachloride, perchloroethylene, trichloroethylene, ethylene dichloride, propylene dichloride, methylene chloride, vinylidene chloride, benzene and for- maldehyde. Because of recent budget constraints, only one site is currently being monitored on a 24-hour basis once every 12 days for those pollutants. Also, sampling methods development work has been done for vinylidine chloride. In addition, AMS has participated with EPA in several special projects including the first integrated en- vironmental management project. This project was designed to develop a methodology to assess multi- media exposures and risks from toxics. One result of this project was that it uncovered some previously unrecognized air toxics sources but it also indicated that point sources of air toxics do not pose a significant health risk in Philadelphia. As part of AMS' multi-year develop- ment plan, AMS is attempting to assess and prioritize risksduetothe "urban soup" of area and small sources. For further information, call Nick Ciciretti, Assistant Chief, Hazardous Air Pollutants Air Management Ser- vices, Philadelphia Department of Public Health, at (215) 875-5681. OAQPS STANDARDS TO CONTROL AIR EMISSIONS FROM HAZARDOUS WASTE TSDF The Office of Air Quality Planning and Standards is preparing national standards that would control organic air emissions from hazardous waste treatment, storage and disposal facilities (TSDF). These standards are being developed under Section 3004(n) of the Hazardous and Solid Waste Amendments (HSWA) of the Resource Conservation and Recovery Act (RCRA) and would apply to facilities required to have a permit to treat, store or dispose of hazardous waste. Sources at TSDF targeted for regulation include process vents, equipment leaks, surface impoundments, tanks and containers. The OAQPS is developing the standards in three phases because of current data limitations regarding sources and controls. Establishing phases also allows OAQPS to more immediately address the potential air impacts associated with technology recently im- plemented in response to land disposal restrictions (e.g., solvent treatment operations). The first phase is intended to control organic emis- sions from process vents and equipment leaks at TSDF. Drawing on experience in regulating these sources in other industries, EPA proposed Phase I Standards on February 5, 1987, (52 FR 3748) for TSDF. The process vent standards are aimed primarily at solvent recyclers 9 ------- and those facilities treating organic-containing waste for ultimate land disposal. Because of recent land disposal restrictions, many have increased the number of solvent removal processes. Emissions sources included the following processes: distillation, solvent extraction, air and stream stripping, thin film evaporation, and frac- tionation. The equipment leak standards would apply to pieces of process equipment such as valves and pumps that handle waste streams containing organics. The equipment leak standards would be essentially the same as those already in place for benzene sources and other organic chemical sources. The Phase I Standards are scheduled for promulgation later this year. The second phase, scheduled for proposal at the end of this year, would significantly reduce organic emis- sions from tanks, containers and surface impoundments. The standards would require covers and/or control devices to control emissions from hazardous waste with a volatile organic content equal to or greater than 500 parts per million by weight. Standards are set under RCRA Section 3004(n) at a level "necessary to protect human health and the en- vironment." Because estimates of residual risk at some facilities after implementation of the first two phases are higher than those historically considered protective under RCRA, OAQPS will examine the need for addi- tional standards in the third phase to reduce unaccept- able risk from those sources. If necessary, it is expected that these standards will apply to specific constituents and may require tighter controls or limiting the amount handled, for example. The third phase is scheduled for proposal concurrent with promulgation of the second phase. Hazardous waste TSDF emit about 12 percent of all stationary source volatile organic compounds. Stand- ards set under these three phases are expected to reduce organic emissions from hazardous wastes over 1.7 million megagrams per year. This emission reduction is also expected to have a significant positive impact on the formation of ambient ozone by eliminating emissions of a substantial quantity of air pollutants that undergo at- mospheric transformation to ozone. Estimated cancer cases nationwide would be reduced by over 130 per year. The maximum level of excess risk of cancer to an in- dividual exposed to emissions from sources regulated in Phase I would be reduced to 1 in 1,000, and from sources regulated in Phase II to 5 in 10,000. Phase III standards, if necessary, will be set to ensure that emis- sion levels result in a maximum cancer risk no greater than 1 in 10,000. Other impacts associated with the third phase have not been estimated. These regulations are required to meet the mandate of protection of human health and the environment; they will result in very substantial reductions in emissions, ozone formation, cancer incidence, and maximum in- dividual risk. Once all three phases are implemented, current estimates indicate that this mandate will be met. For additional information on Phase I, contact Rick Colyer, Standards Development Branch, Emission Standards Division (MD-13), (919) 541-5262, (FTS) 629-5262; on Phase II, contact Dianne Byrne at the same address, (919) 541-5266, (FTS) 629-5266; on Phase III, contact Bob Lucas, Chemicals and Petroleum Branch, Emission Standards Division (MD-13), (919) 541-0884, (FTS) 629-0884. FIRST FIVE TOXICOLOGY P Toxicological Profiles, prepared by the Agency for Toxic Substances and Disease Registry (ATSDR), on beryllium, chloroform, 1,4-dichlorobenzene, nickel and N-nitrosodiphenylamine are now available through the National Technical Information Service* Each profile contains the following: - an examination, summary, and interpretation of available toxicological information and epidemiologic evaluations on a hazardous substance, - a determination of whether adequate informa- tion on the health effects of each substance is available or in the process of development, and - where appropriate, an identification of tox- icological testing needed to identify the types or levels of exposure that may present significant risk of adverse health effects in humans. The Superfund Amendments and Reauthorization Act of 1986 directed ATSDR and EPA to compile a list of ROFILES NOW AVAILABLE the hazardous substances that are most commonly found at National Priorities List (NPL) (Superfund) sites, and that pose the most significant potential threat to human health. ATSDR and EPA jointly prepare guidelines for development of these Toxicological Profiles, but ATSDR alone is responsible for writing the Profiles. Based on these profiles, ATSDR (in consulta- tion with EPA and others) will assess whether adequate information on the health effects of each substance is available. A list of the first 100 hazardous substances for which profiles will be developed was published in the Federal Register on April 17,1987 (52 FR 12866) as required by the Comprehensive Environmental Response, Compen- sation, and Liability Act (CERCLA), Section 104(i)(2)(A). The substances are listed in four groups of 25 substances each. The four groups are listed in descend- ing order of priority, with the first group having the highest priority of the 100 hazardous substances. Chemicals are selected for the list based on their 10 ------- toxicity, frequency of occurrence at NPL sites, and poten- tial for exposure. Estimates of toxicity are, in most cases, based on the values that were derived for defining "Reportable Quantities" under CERCLA. Information on frequency of occurrence at NPL sites and potential for exposure is obtained from various data bases associated with NPL sites. Additional profiles will be announced in the Federal Register as they become available. On the current schedule, 25 should be complete by the end of the year and another 40 ready in draft form. Updated profiles will be released beginning next year. Also, a second list of 100 hazardous substances for which profiles will be developed appeared in the Federal Register on October 20, 1988 (53 FR 41280). For further information, contact the ATSDR at (404) 488-4823, (FTS) 236-4823. *U.S. Department of Commerce, National Technical In- formation Service, Springfield, Virginia 22161. Document numbers (not NTIS numbers) are ATSDR/TP-88107,109, /14, /19, and /20, respectively. VERMONT REGULATION C MOTOR VEHICLE AIR CON On May 24,1989, Vermont's Governor Madeleine Kunin signed into law "An Act Relating to Protecting the Stratospheric Ozone Layer by Eliminating Unnecessary Emissions of Ozone-Depleting Chemicals." Using a series of compliance dates beginning in October 1989, and extending to 1993, the new law phases in the con- trol and eventual elimination of chlorofluorocarbons (CFCs) in automobile air conditioners. The new law regulates CFC recycling equipment used by those who service motor vehicle air conditioners, limits the size of CFC coolant containers that may be sold, and bans the sale of CFC-containing cleaning sprays for non- commercial or non-industrial use, of halon-containing fire extinguishers, except to fire departments, and other CFC-propelled devices. Starting with the 1993 model year, no motor vehi- cle may be registered or sold in Vermont if it contains a CFC-based air conditioner. Vermont is also considering drafting rules for the recovery and recycling of CFC coolant in the servicing of large air conditioning systems and refrigeration units. OVERS CFCs, DITIONING The law further requires Vermont's Agency of Natural Resources to analyze and report to the General Assembly upon: - the condition of the stratospheric ozone layer; - the uses of ozone-depleting chemicals in the State; - advantages and disadvantages of alternative chemicals; - progress in development and manufacture of motor vehicles using alternative air conditioning refrigerants; - opportunities for recovery and recycling of ozone-depleting chemicals including CFCs from refrigerants, air conditioners and motor vehicles that face immediate disposal. For further information on the Vermont law, call Harold T. Garabedian, Acting Director, Air Pollution Con- trol Division, Vermont Agency of Natural Resources at (802) 244-8731. AIR RISC WORKSHOPS ATI FROM ACROSS THE UNITE Air RISC's three-day workshop on risk assessment and communication concluded in May and June, hav- ing served almost 200 people representing 25 State agencies, 33 local agencies and EPA Regional offices. The risk assessment segment included sessions on Risk Assessment Guidelines, Exposure Assessment, the Toxicology and Risk Assessment of Mixtures, and two concurrent sessions on Health Effects Assessment. Session A covered more basic health assessment topics such as basic toxicology, principles of risk assessment, hazard identification and dose-response assessment. The more advanced Session B covered pulmonary 'RACTED PARTICIPANTS D STATES toxicology, pharmacokinetics, noncancer risk assessment-inhalation RfD, and current topics in cancer risk assessment. The risk communication segment was a version of EPA's Office of Policy, Planning and Evaluation two-day course adapted to address local concerns. It covered such topics as Why Bother with Risk Communication?; Perceptions of Risk; Explaining Technical Issues; Deal- ing with the Media; and Trust and Credibility. Both segments used case studies to exemplify the issues. 11 ------- NEED HELP? If your agency needs help in finding information on a specific air toxics question, you can announce that need in the National Air Toxics Information Clear- inghouse Newsletter. Your colleagues from other State or local agencies who have such information will be able to contact you with assistance. In addition, the Clear- inghouse staff would like to receive your ideas for future Newsletter articles. To list an information need in the next i^sue or to submit an article or a suggestion for a future Newsletter article, please call either Scott Voorhees of the Clearinghouse staff, (919) 541-0850, (FTS) 629-0850, or Susan Buchanan, Radian Corporation, (919) 541-9100. HELPFUL NUMBERS Air Risk Information Support Center (Air RISC Hotline): (919) 541-0888 Control Technology Center (Hotline): (919) 541-0800 (FTS) 629-0800 NATICH Clearinghouse Staff: (919) 541-0850 (FTS) 629-0850 The National Air Toxics Clearinghouse Newsletter is published six times a year by the National Air Toxics Information Clearinghouse to assist State and local agencies making decisions on noncriteria pollutant emissions. The first issue appeared in December 1983. The Clearinghouse is being implemented by the U.S. Environmental Protection Agency, Emission Standards Division, Pollutant Assessment Branch as part of a joint effort with the State and Local Air Pollution Control Officials (ALAPCO). The National Air Toxics Information Clearinghouse Newsletter is prepared by Radian Corporation under EPA Contract Number 68-08-0065, Work Assignment 1. The EPA Project Officer is Scott Voorhees, EPA Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina 27711, Telephone: (919)541-5348. The Radian Project Director is Susan Buchanan, P.O. Box 13000, Research Triangle Park, North Carolina 27709, (919)541-9100. The Newsletter is prepared primarily for State and local air pollution control agencies and is distributed free of charge. Those wishing to report address changes may do so by writing Meredith Haley, Radian Corporation, RO. Box 13000, Research Triangle Park, North Carolina 27709. Please contact the Project Officer either with any comments you might have pertaining to this newsletter or with suggestions for future newslet- ters. Articles in the newsletter are written by Radian Corporation or EPA staff unless otherwise indicated. The views expressed in the National Air Toxics Information Clearinghouse Newsletter do not necessarily reflect the views and policies of the Environmental Protection Agency. Mention of trade names or commercial products does not constitute any endorsement or recommenda- tion for use by EPA. Scott Voorhees Pollutant Assessment Branch U.S. Environmental Protection Agency MD-13 Research Triangle Park, NC 27711 FIRST CLASS MAIL U.S. Postage Paid E.P.A. Permit No. G-35 Library EPA, Region XI Woodbridge Avenue Edison, NJ 088-.i7 ------- |