Document LKNY26Dr2m71K76Kk9Xm8vw4Q

m fa The I## Vinyl W m Institute A Division of The Society of The Plastics Industry, Inc. teteiy.ED &00 0e )(wr stlf>y M. Can- April 3, 1987 TO: VI Health, Safety & Environment Committee VI Legal Committee RE: Request For Review: NESHAPS Implementation - "Process Unit" Enclosed is a proposed letter to EPA on their February 4, 1987 memorandum on the "Implementation of the Vinyl Chloride NESHAPS" as it relates to the Agency's interpretation of what is defined as a "process unit". Please review and comment directly to Peter de la Cruz (202-956-5641) by Friday, April 17th. For your information, Peter will be forwarding to you on April 6th, a draft of the brief in the NRDC v. EPA case. Your review of that document obviously takes precedence over the enclosed! MNS/pmb enclosure Meredith N. Scheck Assistant Director cTL028385 Wayne Interchange Plaza II 155 Route 46 West Wayne, NJ 07470 (201) 890-9299 JOSCM C. KCLLCA JCAOMC H. MCCKMAN CHAALCS M MCIMAN WILLIAM N. AOAOHCtANI. JA MALCOLM O. MACAATHUA WATNl V. SLACK maATIn w ACACOVICI JOHN a ClOACO Caaolk C. maaais MICHACL r. MOAAOMC MAAH fOI CVCMS JOHN OUACCH ACTCA L. AC u CAU2 CMAlSTINC A MCAOMCA AMIALCV A. FUJIMOTO LAWACMCC P. MALAAIN AALAM A SIMMONS ACTCA A SUSSCA COWAAO L. AOAWCK JOHN AlCMAAOS* C. OOUOLAS JAAACTT SHEILA A. MILLAA ausscll m rox JAN M. WAMSTCO SUSAN T. CONTI SUSAN J SLUM AaTAICK J. HUAO" s caaio TAurrcsT OAVIO H. JCTT MAUNCIN A. O'CONNCLL** HAACN c. COCLSCAO* NINA M. SIMSTCIN*** SAIAN O. NONDON**' MANN A. SlCVCAS*** AOMITTCO IN ACNNSVLVANIA ONLY 'AOMlTTCO IN VIAOlNIA ONLY LAW OFFICES Keller and Heckman 1150 17TM STREET. N.W. SUITE lOOO WASHINGTON. D.C. SOO30 OAMICL S OIKLCA OUAWAAOf OOOCCN CHAALCS v SAtOCA TCLCX AO OSSSi April 2, 1987 TCLCCOAICA (202) 2SO-TOI CASLCAOOACSS"KCLMAN" WAITCA S OlAtCT OlAL NUMSCA (202)'>*S-564] Hsu FEDERAL EXPRESS Ms. Meredith Scheck The Vinyl Institute Wayne Interchange Plaza II 155 Route 46 West Wayne, New Jersey 07470 Re: EPA Implementation of Vinyl Chloride Standard Dear Meredith Following our discussion at the March 12, 1987 meeting of the Health, Safety and Environment Committee, enclosed is a draft letter to the Enviornmental Protection Agency (EPA) asking them to recind and revise a February 4, 1987 memorandum characterizing the term "process unit" as it applies to the implementation of the 1986 amendments to the vinyl chloride Clean Air Act standard. If you will distribute the draft to the Health Safety and Environment Committee and the Legal Committee, I can receive their comments, revise the letter and forward it to EPA. I look forward to receiving everyone's comments on the draft. Cordially yours Enclosure Peter L. de la Cruz cc Charles E. O'Connell (w/encs.) Lewis R. Freeman, Jr " Robert D. Lus$ Esq. " CTL028386 LAW OFFICES JOSCAM C. HtLLCA jkaomc . hcckman ChaAlSS m mCChan wiluam h. OMhcsani, ja. MALCOLM O. MaCAATMUA WftVNCV ALACK MAATlN W. ACACOVIC* JOHN I. CLDMCO CAMOLC C. MAAAI* micmacl r. moaaonc maah roa CVCM JOHN . OUACCK ACTCA L. CAUX CMAISTIMS A. MCAOHCA smialct s tujimoto LAWACMCC a. MALAAtM AalAM a. SIMMONS ACTCA a. SUSSCA COwAAO l. koawck tcaacncc o joncs MAAT MAATHA McNAMAAA JOHN S. AICHAAOS* c. OOUOLAS JAAACTT SHCILA A. MILLAA ausscll h roa JAN M WAMSTCD ilcnc ainocl mcllca SUSAN T. CONTI SUSAN J. SLUM AATAICK J. MUAD** S CAAIO TAUTfCST OAVIO H JCTT mauaccn a. O'COnncll** KAASN C. COCLSCAO* NINA M. S>N STCl N*** SAIAN O AON DON*** MAAH A. SICVCAS*** AOMITTCO IN ACNNSTLVANIA ONLY AOMITTCO IN VIAOINIA ONLY AOMITTCO IN MAAYLANO ONLY Keller a.nd Heckman 1150 17T" STREET. N.W. SUITE lOOO WASHINGTON. D.C. 20030 (202) 056-5000 April 2, 1987 draft SCitNTiric STarr OaniCL S DIXLCA ouawaao r oooccn CMAALCS V. SACOCA TCLCX AS ssssi TCLCCOAICA 1X021 XSS-7SSX CaSLC AOOACSS -KCLMAM- WAITCA S OIACCT OlAL NUMSCA (202) 965-564 Mr. John B. Rasnic Acting Director Stationary Source Compliance Division Office of Air Quality, Planning and Standards U.S. Environmental Protection Agency (EN-341) 401 M Street, S.W. Washington, D.C. 20460 Re: Implementation of Vinyl Chloride NESHAP Dear Mr. Rasnic: On behalf of the Vinyl Institute, a division of The Society of the Plastics Industry, Inc. (SPI) , we are writing to express our strong disagreement with the positions taken in your memorandum of February 4, 1987 regarding implementation of the vinyl chloride National Emission Standard for Hazardous Air Pollutants (NESHAP) (copy enclosed). Specifically, we disagree with the Agency's interpretation of the term "process unit." The February memorandum also includes a discussion of storage tanks included under the definition of "ethylene dichloride purification." SPI has petitioned for both reconsideration by EPA and review by the Court of Appeals of the EDC definition and other issues. SPI v. EPA, D.C. Cir. No. 86-1640. We have submitted additional information to the Agency demonstrating that there is no need to regulate intermediate storage tanks prior to the final finishing column under the vinyl chloride standard. Because we anticipate that the EDC purification issue will be resolved in separate settlement discussions, the sole purpose of this letter is to review the interpretation of the term "process unit" that is presented in your memorandum. CTL028387 Mr. John B. Rasnic April 2, 1987 Page 2 DR AF.T Keller and Heckman A. Regulatory History of Process Unit Definition Under the 1986 amendments to the vinyl chloride NESHAP, each "process unit" subject to the regulation must implement a formal leak detection and repair program consistent with Subpart V. If less than 2% of the valves are leaking in any process unit, however, the unit is exempt from the valve marking, monthly monitoring, record keeping and reporting requirements of Subpart V. See 40 C.F.R. 61.65(b)(8)(ii). The term "process unit" is defined in 40 C.F.R. 61.241 as follows: "Process unit" means equipment assembled to produce a VHAP or its derivatives as intermediates or final products, or equipment assembled to use a VHAP in the production of a product. A process unit can operate independently if supplied with sufficient feed or raw materials and sufficient product storage facilities. This definition had its origin in the new source performance standards for the synthetic organic chemical manufacturing industry (SOCMI) to control leaks of volatile organic compounds (VOC). See 46 Fed. Reg. 1136, 1153 (Jan. 5, 1981)(proposed 60.481) and 48 Fed. Reg. 48,328, 48,336 (Oct. 18, 1983) (40 C.F.R. 60.481). Subpart V and its definition of the term "process unit" were promulgated as part of the benzene fugitive emission rulemaking. See 46 Fed. Reg. 1165, 1187 , )(Jan. 5, 1981) (proposed 61.111) 23,523 (June 6 1984 (promulgating and 40 49 Fed. C.F.R. R6e1g..2421)3.,498, The SOCMI and benzene rulemaking records suggest a "common sense" approach to interpreting the term process unit. See, Background Information for Promulgated Standards, VOC Fugitive Emissions and Synthetic Organic Chemicals Manufacturing Industry, pp. 5-23 to 5-27 (June 1982) (EPA-450/380-033b)(copy enclosed). As articulated in this SOCMI background document, the intent of the standard is to cover process units that produce the chemicals listed in the regulation. Fairly read, the Agency was crafting a definition that would include the chemicals produced regardless of the process used, even if the chemical was produced only as an intermediate for further reaction during a continuous manufacturing process or coproduced with other chemicals not CTL028388 Mr. John B. Rasnic April 2, 1987 Page 3 draft Keller and Heckman subject to the SOCMI standard. See Figure 5-1 at p. 5-6. This figure and the text make it clear that an entire production step, such as the production of vinyl chloride or its polymerization, constitutes a single process unit. Other EPA documents in the SOCMI proceeding confirm that the Agency was focusing on the production of a chemical product and not discriminating between the various stages in the production of the product. See, Fugitive Emission Sources of Organic Compounds -- Additional Information on Emissions, Emission Reductions, and Costs, Tables 2-12, 2-19 and 3-4 and accompanying text (April 1982)(EPA-450/3-82-010) (copy enclosed). B. Application to the Vinyl Chloride NESHAPS EPA's February 4, 1987 memorandum summarily states that "the tank farm should be considered a separate process unit, as should any common VC recovery system." The memorandum also takes the position that separate polymerization lines are separate process units. From the plain language of the definition as well as the rulemaking record, it is evident that EPA intended to include the entire production process for a volatile hazardous air pollutant (VHAP) within the definition. Clearly, the term "process unit" includes the "sufficient product storage facilities" mentioned in the definition itself. Since "tank farms" are synonymous with storage facilities, this portion of the memorandum is in direct conflict with the plain language of the definition. Making separate polymerization lines separate process units when each polymerization line is using the same VHAP, here vinyl chloride, it makes little sense to treat each line as a separate process unit. Indeed, doing so will create untoward results. For example, if homogenious facilities are subdivided into discrete units under the implementation memorandum, some polymerization lines or storage facilities would be subject to the full panoply of regulation under Subpart V while other sections of the same facility involving the same materials would be exempt under the 2% leaking valve provision. Under the memorandum's approach, for similar equipment producing the same material at the same facility, some portions would be subject to valve marking, record keeping CTL028389 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON. D.C. 20460 FEB -4 1987 OFFICF OF AIR AND RADIATION MEMORANDUM SUBJECT: FROM: Implementation of Vinyl Chloride NESHAP John B. Rasnic, Acting Director''" Stationary Source Compliance Di\^sion Office of Air Quality Planning and Standards TO: Air and Waste Management Division Director Region II Air Management Division Director Region III, V and IX Air, Pesticides, and Toxics Management Division Directors Regions IV and VI The purpose of this memorandum is to address several questions which have arisen concerning the revisions to the vinyl chloride NESHAP and the incorporation of Subpart V into this standard. The questions are as follows: 1. What part of a plant's leak detection and elimination program is subject to Subpart V and when does it become subject? Note: There are no changes to the requirements for fixed monitoring. These requirements are described in 40 CFR 61.65 (b)(8)(i). For routine leak detection, plants must comply with Subpart V within 90 days of the effective date, or by December 29, 1986. However, if an owner or operator can demonstrate that less than 2.0% of valves are leaking in any process unit, then that process unit is exempt from 61.242-l(d) (marking), $61.242.7(a), (b), and (c) (monthly monitoring of valves), 61.246 (recordkeeping), and 61.247 (reporting). The exemption for marking, recordkeeping, and reporting applies to the entire process unit. CTL028390 2- - To demonstrate that less than 2.0% of valves are leaking, the owner/operator must conduct a performance test initially, annually, and at any other times requested by the Administrator. This performance test must be done for each process unit. If, during any performance test, the percentage of leaking valves exceeds 2.0%, then the owner/operator must comply with Subpart V within 90 days. A plant's past program for routine leak detection is no longer required, nor does it necessarily meet current require ments. A process unit will continue to be exempt from the above-mentioned provisions of Subpart V so long as the percen tage of leaking valves remains below 2.0%. However, if a process unit subject to Subpart V subsequently has less than 2.0% leaking valves, that unit could elect the alternative standards of S61.243-1 (allowable percentage of valves leaking) or 61.243-2 (skip period leak detection and repair). The marking, recordkeeping, and reporting requirements would apply irrespective of the chosen standard. The exemptions to Subpart V contained in the standard were designed to avoid unnecessary changes to existing leak detec tion plans which are effective in detecting and repairing VC leaks. Therefore, once the percentage of leaking valves exceeds 2.0% causing the owner/operator to modify the leak detection plan to comply with Subpart V, the purpose for the exemption no longer exists. Thus, once a plant is required to comply with Subpart V, it is no longer possible for that plant to re-qualify for the 2.0% exemption in Subpart F. 2. What does the terra "process unit" include? In Supart V, "process unit" is defined as "equipment assembled to produce a VHAP or its derivatives as intermediates or final products, or equipment assembled to use a VHAP in the production of a product", and which can operate independently if supplied with sufficient raw materials and storage facili ties. Each separate polymerization line is therefore a separate process unit. Additionally, the tank farm should be considered a separate process unit, as should any common VC recovery system. (This is consistent with the benzene NESHAP and with the analysis supporting the benzene NESHAP.) 3. What calibration gas is required for monitors: methane or hexane as specified by Subpart v, or VC? CTL028391 -3- The fixed area monitor should be specific to and calibrated with VC; otherwise, other organics in the air could mask the VC concentration. The routine leak detection monitor may be cali brated with methane, hexane, or VC (because VC cylinders at high concentrations may be difficult to obtain and may present safety concerns, methane or hexane is recommended). Use of methane or hexane is an acceptable alternative and can be approved upon application. 4. What storage tanks, if any, are included in ethylene dichloride purification? The standard defines EDC purification as any part of the process of EDC production following EDC formation, excluding storage following the final finishing column. Consisent with this, the Response to Comments document states that both intermediate and final product storage following the final finishing column are exempted. Therefore, the exemption applies to intermediate and final product storage following the final finishing column. Product storage tanks prior to the final finishing column are included in ethylene dichloride purifica tion. To further assist you in implementing this regulation, I am attaching a copy of the vinyl chloride NESHAP compiled by the Environmental Reporter and obtained by Bruce Varner of Region V. This compilation combines the recent revisions with the existing standard to alleviate the need for two documents. If you have further questions, please contact Jim Engel at PTS 382-2877. Attachment cc: Richard Chakot, Region II Ron Patterson, Region III Wayne Aronson, Region IV Bruce Varner, Region V Martin Brittain, Region VI Chuck Seeley, Region IX Bob Agax, ESED CTL028392 t&EPA Untied States Environmental Protection Agency Office of Air Quality Planning and Standards Research Triangle Park NC 27711 EPA-450/3-80-033b June 1982 VOC Fugitive Emissions in Synthetic Organic Chemicals Manufacturing Industry-- EIS Background Information for Promulgated Standards CTLO 28393 5.4 PROCESS UNIT DEFINITION Conment: Five conment letters (IV-D-15; IV-D-17; IV-D-20; IV-D-14; IV-D-21) said that the definition of process unit was vague. Two of the commenters (IV-D-14; IV-D-21) cited potentially confusing situations in which the standard might be misapplied to solvent recovery operations. One (IV-D-21) recommended that the definition include the conditions that the chemical be produced by chemical synthesis. Another commenter (IV-D-51) wrote that, as proposed, "process unit" means equipment assembled to produce, as intermediates or final products, one or more of the chemicals listed in Appendix E (60.489). The key word of the definition in the context of the overall intent of the Subpart VV is the word "produce." The commenter added that as the Administrator explains in the preamble the applicability of Subpart VV is for facilities that produce the listed chemicals and not facilities that use them. He expressed concern that unless this point is clarified it may be interpreted that process units that purify or recover the listed chemicals are producing them. The commenter stressed that to produce a chemical means to convert raw materials by one or more reaction steps to the desired chemical which may be either an intermediate or a final product. He reconmended that the following sentence be added to the definition of process unit: "Process units that handle, but do not form by chemical reactions, the chemicals listed in Appendix E (60.489) are excluded 'rom this subpart." Another commenter (IV-D-14) recorranended that a definition of inter mediate products be included to avoid the potential misunderstanding. Response: Process unit is defined as equipment assembled to produce, as inter mediate or final products, one or more of the SOCMI chemicals (listed in 60.489). A process unit can operate independently if supplied with sufficient feed or raw materials and sufficient storage facilities for the product. The definition was drafted to provide a common sense, practical way to determine which equipment are included in an affected facility. There are 5-23 CTL028394 no specific physical boundries or size criteria. The definition instead depends upon several operational factors, including chemical produced and the configuration of the processing equipment. The configuration of the processing equipment may be different for different producers of the same chemical, and, therefore, it may be fairly site-specific. However, in practice, the definition will implement the selection of a process unit basis as the "source" covered by the standards. The intent of the standards is to cover process units that produce the chemicals listed in 60.489, either by chemical reaction or by other processing means, such as separation and purification techniques. EPA sees no justification in specifically excluding solvent recovery operations. VOC fugitive emissions occur from equipment in VOC service. Therefore, if there are any fugitive emission sources in VOC service in a process unit producing one of the chemicals listed in 60.489, they should be covered by the standards. These equipment components would be present in a process regard less of whether it is a chemical synthesis or separation process. It would, therefore, be inappropriate to define process unit by requiring that a chemical be produced by chemical synthesis or by a separation process. Solvent recovery operations will be covered by the SOCMI standards if they are producing chemicals listed in 60.489. EPA has considered the impact on producers of all these chemicals. The impact on SOCMI units located in solvent recovery plants is no different from the impact on SOCMI units located in chemical plants. Intermediate chemicals are typically those chemicals produced from raw materials which are then used captively to generate a final product(s). The equipment assembled to produce an intermediate chemical constitutes a process unit if it can be operated independently when provided sufficient storage for raw materials as well as the intermediate chemical itself. Thus, any process unit producing a chemical listed in 60.489 as an intermediate chemical would be covered by the standards. Furthermore, chemicals listed in 60.489 that are produced as coproducts in a process unit would also result in coverage of that unit by the standards. Examples of coproducts are phenol and acetone. Chemicals 5-24 CTL028395 listed in 60.489 produced as by-products, on the other hand, would not result in coverage of that unit. By-products are produced as a consequence of producing other chemicals and are not gathered together for any subse quent purpose. By-products may be found as trace contaminants in the final product of a chemical production process unit. Comment: Another commenter (IV-D-15) cited a potential problem in defining when an upstream process unit is an affected facility. He cited as an example a crude unit in a petroleum refinery which produces intermediate refinery streams which may contain 10 percent or more VOC per the proposed ASTM methods. These streams may feed a unit which will eventually produce a SOCMI chemical. In such instances it was not clear to the commenter which streams would be covered. He recommended that only the downstream unit be covered. Response: The SOCMI NSPS for fugitive VOC sources regulate process units that produce chemicals that are either photochemically reactive substances, use photochemically reactive chemicals as additives or reactants in the production process, or have photochemically reactive co-products. The chemicals covered by these standards are listed in 60.489. Therefore, if the intermediate product is one of the chemicals listed in 60.489, the unit producing it is covered by the standards. If the downstream unit also produces one or more chemicals on the list, it will also be covered by the standards. The following example is offered for purposes of clarification. Figure 5-1 shows a configuration of a hypothetical petroleum refinery or chemical plant. In this hypothetical complex, there are three processes. Process X uses SOCMI and non-SOCMI raw materials to produce a non-SOCMI chemical and non-SOCMI co-products. Process unit X would not be covered by the final SOCMI standards because SOCMI chemicals are not produced. Process unit Y uses non-SOCMI chemicals to produce another non-SOCMI chemical and a SOCMI chemical co-product.a Process unit Y would be covered aIf this production is less than 1,000 Mg/yr, the unit may be excluded under the lower production volume cutoff. See Section 5.7. 5-25 CTL028396 SO CM I SOCMI cir r0\>\ non-SOCMI chemical non-SOCMI chemical non-SOCMI SOCMI chemical chemical non-SOCMI chemical NOTE: Process units enclosed in dashed boxes would be affected facilities under the SOCMI standards. Figure 5-1. Example for process unit definition. CTL028397 by the standards because it produces a SOCMI chemical. There is an exception to this coverage, however. If the production of the SOCMI chemical co-product is less than 1,000 Mg/yr, the unit may be excluded under the lower production volume cutoff (see Section 5.7). And as discussed in the previous response, if the SOCMI chemical is a by-product (not a co-product) that is not collected for any purpose (such as product recovery) and remains in the final non-SOCMI chemical product in trace quantities as an impurity, the unit would not be covered by the standards (see previous response). Process unit Z uses the SOCMI coproduct produced in Unit Y and purchased SOCMI materials to produce another SOCMI chemical and a non-SOCMI co-product. Process unit Z would be covered by the standards. However, the non-SOCMI co-product stream would not be covered after the point of removal from the reaction products. Comment: Another potential problem with the process unit definition was cited by one of the commenters (IV-D-20). He cited an example of an FCC unit which produces streams containing significant amounts of propylene. The major purpose of the unit is to produce gasoline. However, the propylene produced is fed directly into a polymer plant. He did not feel it appropriate to cover that plant by the proposed standards because the propylene is a transient intermediate which is not stored or sold as a finished product. Response: The fact that a product is not stored or sold as a finished product has no effect on fugitive emissions. A unit that produces propylene would be covered by the SOCMI fugitives NSPS unless none of the fugitive emission sources are "in VOC service." In the example cited by the corrmenter, propylene is a co-product of the gasoline production operations. Under the final standards fugitive emission sources from the point of production of propylene to the point of raw material storage or reaction in the polymer unit would be covered if they are in VOC service. 5-27 CTL028398 ?EPA Umif*(1 States Environmental Protection Agency Other* ol Ar Qu.i1 Planning and Standards Research Triangle ^aik N;C 2/71 1 L'F'A 4b0 3 Apnl H'r,.'' Fugitive Emission Sources of Organic Compounds -Additional Information on Emissions, Emission Reductions, and Costs CTL028399 old plants were not revealed. The 0VA-108 was used for screening (leak identification) and for leak rate determination (analysis of collected leak vapors). The leak rate was determined by taking Tedlar bags partially filled with air and enclosing the leaking valve. The hydrocarbon concen tration in the bags was recorded as a function of time. Leak rates were determined for a total of 6-8 valves. Visual estimates of the initial bag volume were assumed to be +5 percent. The screening data from the DuPont study are shown in Table 2-10. DuPont concluded from the data collected that no significant difference in leak frequency exists between manual and automatic control valves. Significant trends were observed with changes in product vapor pressure. It also seemed that full open or closed valve seat positions resulted in lower leak frequencies than intermediate positions. 2.1.5 Exxon Cyclohexane Study 18 A fugitive emissions study was conducted by Exxon Chemical Company at the cyclohexane unit at their Baytown plant. The total number of valves, pump and compressor seals, and safety valves were determined. For all sources, except valves, all of the fugitive emission sources were sampled. For valves, a soap solution was used to determine leaking components. All leaking valves were counted and identified as either small, medium or large leaks. From the set of valves found to be leaking, specific valves were selected for sampling so that each class of leaking valves was in approxi mately the same proportion as it occurred in the cyclohexane unit. Heat resistant mylar bags or sheets were taped around the equipment to be sampled to provide an enclosed volume. Clean metered air from the filter apparatus was blown into the enclosed volume. The sampling train was allowed to run until a steady state flow was obtained (usually about 15 minutes). A bomb sample was taken for laboratory analysis (mass spectrometry). Table 2-11 presents the results of the Exxon study. 2.1.6 EPA 24-Unit Study19 EPA coordinated a study in 1980 to develop information about fugitive emissions in the SOCMI. A total of 24 chemical process units were selected 2-14 CTL028400 for this purpose. The process units were selected to represent a crosssection of the population of the SOCMI. Several of the factars considered during process unit selection included annual production volume, number of producers, process conditions, corrosivity, volatility, toxicity, and value of the final products. Table 2-1? shows some of the factors considered in selection of process unit types. Several of the chemicals on the list are either carcinogens or suspected carcinogens: acrylonitrile, ethylene dichloride, formaldehyde, perchloroethylene and vinyl chloride. The screening work began with the definition of the process unit boundaries. All feed streams, reaction/separaticn facilities, and product and by-product delivery lines were identified on process flow diagrams and in the process unit. Process data, including stream composition, line temperature, and line pressure, were obtained for all flow streams. Each process stream to be screened was identified and process data were obtained with the assistance of plant personnel, in most cases. Sources were screened by a two-person team (one person handling the hydrocarbon detector and one person recording data). The Century Systems Models 0VA-108 and OVA-128 hydrocarbon detectors were used for screening. The HNU Systems, Inc., Model PI 101 Photoioniza tion Analyzer was also used to screen sources at the formaldehyde process unit. The detector probe of the instrument was placed directly on those areas of the sources where leakage would typically occur. For example, gate valves were screened along the circumference of the annular area around the valve stem where the stem exits the packing qland and at the packing gland/valve bonnet interface. All process valves, pump seals, compressor seals, agitator seals, relief valves, process drains, and open-ended lines were screened. From five to twenty percent of all flanges were randomly selected and screened. For the purpose of this program "flanqe" referred to anv pipe-to-pipe or tubing-tn-tuhing connection, excluding welded joints. Each screening instrument was calibrated on a daily basis, at a minimum. The model 0VA-I0R instruments, with logarithmic scales reading from 1 ppmv to 10,000 ppmv, were calibrated with high (8,000 ppmv) and low 2-17 CTL028401 TABLE 2-12. FACTORS CONSIDERED IN SELECTION OF TYPES OF PROCESS UNITS3 - 24 Unit Study - Chemical Product Acetaldehyde Acetone Ac rvlnn i t ri 1 e Adipic acid Cumene E thylpne Ethylene dichloride Formaldehyde Methyl ethyl ketone Methyl methacrylate Perchloroethylene Phenol 1 ,1 ,1-Trichloroethane Trichloroethylene Vinyl acetate Vinyl chloride monomer Production 0 volume 10* Ib/yr (1977) <1.7 7.2 1.6 1.5 2.6 25.4 11.0 6.0 0.5 0.7 0.6 2.3 0.6 0.3 1.6 6.0 Number of producers 0977) 5 13 4 5 14 31 12 16 5 3 8 13 3 5 6 12 Vapor pressure of product, mn Hg at 20C 7604 160.5 84.9 <1.1 3.3 760+ 60.2 760* 76.2 28.1 13.7 <1.7 95.6 57.0 84.2 7604 aSource: Reference 22. ^Fiqht-hour time weighted average. threshold limit value not available or not established. Threshold . limit value0 of product, ppmv 100 1000 20(skin) NAC 50(skin) NAC 10 2 200 100 100(skin) 5(skin) 350 100 10 5 Cost of product, i/lb (1980) 0.29 0.30 0.38 0.53 0.27 0.24 0.14 0.07 0.35 0.50 0.23 0.36 0.31 0.27 0.34 0.22 CTL028402 (5C0 ppmv) concentration methane-in-uir standards to ensure accurate operation at both ends of the instrument's range. The model OVA-128 instruments, with linear readouts ranging from 0 ppmv to 1,000 ppmv, were also calibrated with high and low concentration standards. A pre-calibrated dilution probe was used with the OVA-128 when calibrating with the 8,000 ppmv standard. The HNU Photoionization instrument, used to screen the formaldehyde process unit, was calibrated with isobutylene, which has an ionization potential close to that of formaldehyde. Results of the screening program at the 24 process units are summarized in Table 2-13. 2.1.7 EPA's Position at Proposal After considering the data available at proposal, EPA estimated fugitive emissions of V0C from S0CMI by using the emission factors developed in the study of fugitive emissions in petroleum refineries. The petroleum refinery data are the most comprehensive and definitive fugitive emissions data available and the study had been designed to produce emission factors which would estimate uncontrolled fugitive emissions of V0C. The use of petroleum refinery data to characterize emissions from S0CMI units was based on the position that equipment handling similar substances would behave similarly and therefore emissions from similar equipment in V0C service should be similar. The available S0CMI fugitive emissions data also supported this judgement. (Tables 2-14 and 2-15 show a comparison of the results of the studies of fugitive emissions available at the time of proposal.) Furthermore, the refinery fugitive emissions data were collected before an awareness of the magnitude of fugitive emissions became wide spread, and, therefore, the petroleum refinery emission factors are considered representative of fugitive emissions in the absence of a leak detection and repair program. Thus EPA concluded that emissions from S0CMI in the absence of a leak detection and repair program could be estimated using emission factors developed for fugitive V0C emission sources in petroleum refineries. 2-19 CTL028403 TABLE 2-19. PERCENT LEAKING FOR EACH CHEMICAL UNIT TYPE AS A FUNCTION OF SOURCE TYPE AND STREAM SERVICE IN SOCMP (units)**Source/Chemlcal Vjlv Vinyl Ac ct ate (1,3) 1 t liyl.Mic (2.4.11) 1 iimetie (5,6) At el /I'liein* 1 (12) 1 Hu 1' I'i.Ii.oilde (21.29) lluyl ............. . M-'nnn.fr (7',?fl) l < t #.i t l li f (22) i it > l i 11* 1 i I'm* ( ) 1 . J 2) A. el a . .i. ii. ji* i 33) Hr i i y 1 Mi ( i i' i > l .i| c A-l i j* 1 > 111 ( J5.66) ( l 1 >r m.i t * il Itli.tne* ( )* 1 (60, 02) A. r y I "ii 1 ( r 1 le (65.66) l . \ . 1 * \ i l c \ o t oi i turn (.')) 1 S,.l 1 * V 1/ 1 Aftlilf ( 1 . ) ) ! . I r1 2.t . 1 1 | Ai t 1 "``I /1 In | (12) Hli)linc IMiMorlde (71.79) Vinyl < > l u r 1 de Mmtome r ( 20,78) k r m. 1 deliyde (72) Mi | It y 1 1 thy 1 Art ne (31. 12 > A. el a Idehydc ( 1 )) Me 11* y 1 He 1 l.i r y 1 ,i i r (36) Ad(*u Add (35.66) 1 hln lii.ilril f lit me a ( 60,62) Airyltutilrlli (65,66) I | . 1 - T r 11 Ii ! r.i t bane (* t ) Number Sc reenrd CAS Number Leak Inf Percent Leaking 969 6296 66b 8 60) M2 61 20/ l 7h IW> 95 68 396 -- -- -- -- -- -- -- -- -- -- -- 35 9)6 6) 0 6 30 1 19 8 0 0 0 s -- -- -- -- -- -- -- -- -- -- -- 3.7 16.8 16.1 0 1 .0 7. ) 2.6 9.2 4.5 0 0 0 2.) -- -- -- -- -- -- -- -- -- -- -- LIGHT LIQUID Number Screened Number Leaking Percent 1 raking 21)) 6 1 76 709 1818 2256 1709 171 671 551 1058 17 16 JO 1696 ))) 89 76 25 86 58 65 8 )i 32 65 60 61 10 8 969 86 6 212 0 36 3 1 0 in 28 6 20 6 2 3 7 0 1 3 2 1 0.6 21.2 10. 5 II. ) 1.1 1.0 0 5. 1 0. 5 0.1 0 06 0.9 1 .1 4.5 26.3 16.0 2.) 5.2 10.8 0 3-2 9.6 6.6 H. 1 M. 2 10 n Number MLAVY LIQUID Number Percent Leaking 126 )2); 198 688 -- -- -- -- -- -- 1678 j2 95 5 15 3 36 -------- 30 H -- 0 13 0 c -- -- -- -- -- -- 0 0 0 0 11 0 0 -- -- -- -- -- -- i r. " 0 0 0 0 -- -- -- J G 0 0 -- -- -- -- 00 7 -- 75.r - (Cfnt timed ' |1 1 1 1 CTL028404 TABLE 2-19. (CONTINUED) Sour cc/Ct.a lea 1 (ant ts}^` Huaber Screened CAS Nuaber Leaking Percent Leaking Nuaber Screened LICHT LIQUID Nuaber Leaking Percent LeakIng HLAVY LIQUID Number Sc reened Number Leak log Percent Leak 1ng i Vinyl Acetate (IJI lll.yl.nc < ien (3,6) 11) \l r t !*/I'lu MO 1 (12) Ltl.y U-.u Hi. M. i id* (21, .*9) Vinyl < h I or i .1% (Jti.Jg) f f 1 -.i 1 1*li y.1t i 2 .* * IW1 liy 1 1 * I* y 1 Attune ( 11 , W ) At i'l u litrl*>dr ()j) Hr lltyl M, (h.i, (yl i|. a.i11*i a. id * n.6- 1 t l- l foil ii.lied ItlitfiiiH (60 , 6 2) Aiifl.oillfltr 1b 3.66 1 1 . I . 1 - T f klilofu(`''>< ( * 1 ) <t|*M l*J* d 1 If'r* Vinyl A.itllf tl.)) I 1 f 1 It* ( 2 , 4 , \ \ ) I........ 1% b> A. rtuM/l "u| ( 1?) 1 llijrltlir iHvl.lorldr (21,29) Vinyl (.Murid* rtonoer (20,28) 1 u i an 10et>yJc (22) Miil.yl flltyl At tune ()f,J2) Act 1 a Idcl.ydr ( ) ) I Hr 1 liy 1 rtcdi.M 1 y 1 .11 * Adl|>li At 1 d (D.fcl) iiitmliuiri) liliAnc. (34) (60,61) Acrylonitrile (b3,6b) 1 1 .1 -Tr 1. t.) .... (61) 102 63; 16) -- 2\ )b 2 22 j) 38 49 16 U7 -- 145 304 6 2 100 >4 u )) It 63 19 n 116 -- 3 39 19 -- 1 2 0 0 0 0 u 0 2 -- 8 3) 0 0 0 2 0 J 3 0 0 0 1 -- 2,8 6.2 4.: -- 4,0 12.4 0 0 0 0 0 0 l.; -- 4.4 12.1 0 0 0 3.6 0 8.1 8.8 0 0 0 0.9 -- m 402 '.68 82 163 42 8 76 Uh 242 2 46 2 182 23 318 2 14 13 318 473 3t0 36 J 06 138 334 1 412 t86 111 0 24 9 0 1 0 1 0 0 0 0 0 u 0 ft 41 2 ft lb 18 0 19 8 1 0 6 12 2 0 6. V 1.6 0 0.6 0 12.4 0 0 0 0 0 0 0 2.3 19.2 13.3 1.3 3.4 4. 3 0 30. 2 3.1 0. 3 0 1.3 2.3 I8 B 69 130 JO -- -- -- -- -- -- 320 2 28 -- 22 91 1 102 -- -- -- -- -- 2144 3ft 0 U J 1/ -- -- -- -- -- -- 0 0 l< ---- 2 0 'J 0 -- -- -- -- -- -- 0 0 4 0 c {* o -- -- -- -- -- -- V * * 9.1 0 0 0 -- -- -- -- ----------- 0 0 10. 3 aSource: Reference 36. ^Unit numbers represent the unit number designation reported in the 24-Unit Study (Reference 37). CTL028405 determining emission factors, and EPA did not consider them representative of the industry. In contrast, commenters requested that thesp data and other new data be used in making emission estimates for this industry. EPA agrees that these data could be used to estimate the percent of fugitive emission sources which leak. EPA continues to believe, however, that data from petroleum refineries are appropriate for estimating the quantity of VOC emissions from sources which leak, except for valves in gas service. The percent of fugitive emission sources which leak and the quantity of VOC emissions from sources which leak are the primary factors which influence the Quantity of VOC emissions from fugitive emission sources. Average Unit Concept -- Review of the available data on fugitive emissions from SOCMI indicated considerable variability among the process units tested (see Table ?-19). This variability is consistent with EPA's understanding of the nature of the group of industries which make up the SOCMI industry category. In an industry category composed of production facilities for chemicals, no one type of process unit could be considered typical. However, estimation of national impacts is dependent on the extrapolation of emissions from a typical unit to the entire U.S. population of units in SOCMI. Therefore, it is necessary to generate a single set of emission factors which can be considered as an "industry average". The situation is similar to the one found in the petroleum refining industry. Just as in the SOCMI units tested, wide variability was seen in the emissions from different units in the refineries tested (see Tables 2-2 through 2-6). EPA uses a single set of emission factors to represent an "average" refinery even though in reality an "average" refinery may not exist. In the same manner EPA decided to generate a set of emission factors which represent an "average" SOCMI unit. Development of Emission Factors -- As indicated earlier (p.2-56), EPA determined that the best studies on which emission estimates for SOCMI emission sources could be based were the Petroleum Refinery Study 104 and the Twenty-four Unit Study. 105 Also indicated earlier, EPA considered these data sets to show differences between the SOCMI data and the petroleum 2-57 CTL028406 TABLE 3-4. SUMMARY OF SELECTED EQUIPMENT COUNTS FOR MODEL UNITS AND UNITS IN SOCMI 24-UNIT STUDY3 Unit Number Process Type Safety/reltef Valves In-line valves light Heavy Gas Liquid Liquid Upen-endcd lines Li girt "Heavy Gas Liquid Liquid A Model unit B Model unit C Model unit 11 42 130 90 365 1117 84 335 1037 84 335 1037 9 37 115 47 189 581 48 189 581 1 2 3 4 5 6 11 12 20 21 22 2B 29 31 32 33 34 35 60 61 62 64 65 66 Vinyl acetate Ethylene Vinyl acetate Ethylene Cumene Cuncnc Ethylene Acctone/phenol Ethylene dtchlorlde Vinyl chloride monomer formaldehyde Ethylene dtchlorlde Vinyl chloride monomer Methyl ethyl tetone Methyl ethyl ketone Acetaldehyde Methylmethacrylate Adipic acid Trichloroethylene/ perchloroethylene 1,1,1 - Trlchloroethane Ethylene dtchlorlde Adipic acid Acrylonltrllc Acrylonitrile 3 Reference 11. ^Reference 12. 31 47 31 101 10 IB 65 29 30 18 3 10 4 1 2 15 21 5 5 - 377 2563 872 2425 123 422 2396 B 390 93 40 168 420 82 169 236 220 48 52 788 1412 1570 2295 354 573 1118 2075 916 751 126 474 1806 348 389 610 1179 17 1800 67 1311 61 54 71 177 59 530 1232 12 37 56 142 79 2 4 208 2 43 4 16 27 116 12 27 51 73 4 21 29 61 292 221 430 723 1093 342 ~ 22 29 114 77 68 * 1------------- ' 49 39 305 59 6 10 144 582 230 44 37 13b 470 107 97 168 351 1 483 130 202 370 8 93 15 3 1 Ill 200 4 * 122 48 Pu*t>s Light Heavy Liquid Liquid Coagrressors 8 29 91 7 30 93 1 2 8 44 22 49 35 10 15 27 90 45 10 8 22 51 15 16 32 49 60 10 - 24 42 5 16 1 2 36 - 60 33 10 * 4 8 4 3 2 7 - 1 - " *, * 1 2 Flanges 600 2400 7200 1940 5340 3820 159B0 875 2990 1220 2200 1020 900 200 280 2840 820 1140 080 1475 1175 2760 410 45 770 1310 1935 CTL028407