### Occidental Chemical Corporation OxyChem ® A subsidiary of Occidental Petroleum Corporation 5005 LBJ Freeway, Suite 2200, Dallas, Texas 75244

-6152 P.O. Box 809050, Dallas, Texas 75380-9050 Phone: 972-404-3800

July 10, 2015

Mr. Brian Cook EPA Office of Atmospheric Programs Climate Change Division - Greenhouse Gas Reporting Branch U.S. Environmental Protection Agency 1200 Pennsylvania Avenue, NW, Mail Code: 6207J, Washington, DC 20460 Subject: Request to Consider IPCC Balanced EDC/VCM Process Studies and Data for the Elimination of eGGRT Validation Messages at VCM Production Facilities Reporting Under Subpart X Occidental Chemical Corporation (OCC) wishes to present information and an explanation of our VCM production processes for the purpose of supporting a request to adjust Subpart X data requirements within the eGGRT reporting system. OCC believes that initiating this request will eliminate validation messages that a number of our vinyl chloride monomer (VCM) plants received, and other Subpart X sources may have received, during eGGRT reporting in the past few years. OCC assumes that studies published by the Intergovernmental Panel on Climate Change (IPCC) were used by EPA in developing an error message trigger designed to flag Subpart X reporting facilities within the eGGRT online data reporting program. Therefore, it is our presumption that the values shown on the table in Appendix B (attached below) were used by EPA to determine validity (accuracy) ranges for the CO2 totals reported in Subpart X. While OCC does not have a problem with the mass balance equations provided in the rule for calculating CO2 emissions, we do believe the data validation messages are the result of two issues:

 The calculation instructions under subpart C exempting the burning of hazardous waste having fuel value

 The eGGRT data reporting system requests an accurate annual production value for EDC produced without consideration that EDC may exist as a non-isolated intermediate within a VCM production process Concerning the first issue, Subpart X currently allows submittals using two different methods to calculate emissions – 40 CFR Part 98.243(b) and 40 CFR 98.243(c). Subsection 243 (b) is only applicable to those sources that have CEMS installed on all emission sources. The sources at OCC facilities that were notified concerning the subject validation errors in the past are not equipped with CO2 CEMS, and thus must rely on the mass balance approach listed in 98.243(c). This option is referenced in §98.242(b)(2), which states “ If you comply with § 98.243(c), report CO2, CH4, and N2O combustion emissions under subpart C of this part (General Stationary Fuel Combustion Sources) by following the requirements of subpart C only for the combustion of supplemental fuel.” Thus, for the EDC/VCM facilities, emissions from the combustion of supplemental fuel have been reported under subpart C. A reporting issue may develop if the use of subpart C emissions are used toinitiate a validation message based on IPCC’s ratio MT CO2/MT EDC Production since the CO2

component from the combustion of Hazardous Waste is not accounted for in subpart C GHG calculations as discussed in the next paragraph. Subpart C of the GHG reporting rule does not require accounting for CO2 unless one of two conditions are met as stated below in the rule: 40 CFR Part 98‚ Section 30‚ Paragraph (c) For a unit that combusts hazardous waste (as defined in §261.3 of this chapter), reporting of GHG emissions is not required unless either of the following conditions apply: (1) Continuous emission monitors (CEMS) are used to quantify CO2mass emissions. (2) Any fuel listed in Table C-1 of this subpart is also combusted in the unit. In this case, report GHG emissions from combustion of all fuels listed in Table C-1 of this subpart. When the estimated CO2 component for the amount of hazardous waste burned is added to the Subpart C CO2 reported and is divided by the plant’s VCM production, the MT CO2 per MT VCM production ratios show differences ranging from 8.1 to 21% compared to the IPCC table values (see Spreadsheet Table in Appendix A – column D). We believe the close agreement with IPCC indicates our calculation of CO2 is within an acceptable range when adding an estimated contribution to total CO2 to include burning hazardous waste at the plant, and provides a basis for EPA’s review and modification of the data validation error algorithm within eGGRT. The second issue involves the use of IPCC factors based on EDC production values. The EDC production number required in eGGRT does not recognize that our facilities are configured to produce VCM as the end-product. The discussion that follows concerns the use of published IPCC data (shown in table 3.17 in Appendix B) which recognizes process ratios based on either VCM or EDC production processes. In using either the VCM production or EDC production basis, the (Subpart X) method of calculation of CO2 emissions remains the same. It is important to again recall that the three VCM facilities are not stand-alone ethylene dichloride (EDC) manufacturing plants. EDC is a continuously produced as an intermediate which is circulated through multiple recycle and return streams beginning with ethylene as feedstock to feed what is essentially balanced and integrated EDC/VCM processes. In addition to the intermediate EDC produced, our plants may purchase EDC to supplement feedstock for VCM production. Since VCM is the final product, the company uses calibrated instrumentation to ensure that VCM production is accurately measured for cost and sales accounting purposes. The EDC circulates inside the VCM production process through various direct pass feed streams, recycle,reclaim and product recovery process loops. As a result, direct measurement accounting of an endproduct EDC intermediate feed stream is not performed. As an example, within the VCM production process itself, the amount of EDC that the process receives in any single pass varies in a fairly wide range around a concentration of 55%. Since the recycle stream varies in flow and concentration and thesechanges occur instantaneously, numerous measurement and quantification issues arise that impact any

effort to represent a total EDC (as an intermediate) “production” value. Simply stated, the issue of totalizing an EDC value is complex, since varying amounts of unreacted EDC present on any “pass” will, by process design, be recycled back to a purification system before it is reintroduced again to the VCM production section of the process. Multiple in-process analyzers, computerized totalizers and complex datalogging would be needed. Our process technical staff believe that a significant portion of the process configuration would have to be changed to attempt to measure EDC, which would likely have little to no overall benefit (in generating an accurate “pounds CO2 per pound of product” factor) over the proposed methodology of using VCM production values especially since IPCC incorporates published factors for both EDC and VCM in their reports. Since the only option currently provided in eGGRT is to enter an EDC production value, OCC does enter an EDC production number based on a molar relationship of one mole of EDC per mole of VCM produced which equates to 1.583 pounds of EDC per pound of VCM. This conversion factor is chemically defined and is based on the known reactions and chemical balance for converting EDC to VCM. Utilizing just the EDC production numbers derived from VCM production and based on the 1.583 conversion factor (see column F in the Appendix A Table) the percentage difference in OCC related calculated “actual” to IPCC values ranges from 13% to 25%*. As noted previously, there is closer agreement with the IPCC values when the CO2 emissions from the combustion of hazardous waste are added into the Subpart C emission calculations. OCC wishes to underscore that there is no change in the actual overall CO2 calculated for reporting. As a result of the information presented above, OCC’s VCM plants have incorporated the 1.583 factor in their basis calculations for reporting of EDC in the eGGRT system and we present it here to explain our logic and analysis for its use. In summary:

1. OCC believes that its VCM facilities should not be subject to future data validation errors if the CO2 component from burning hazardous waste with heating value is applied. 2. OCC would like direction on the best way to communicate the quantity of CO2 from burning hazardous waste, with thought given to CBI concerns, whenever a validation error message appears. 3. OCC believes that eGGRT should provide a menu option for VCM production to allow entering VCM production for balanced EDC/VCM production processes where EDC is an intermediate and not a final product. 4. If the rule is opened in the future, OCC will request allowance to report VCM production based on the analysis described in this correspondence, particularly noting IPCC’s observation that: ...“The CO2 emission factor that will be applied will depend upon whether activity data for EDC production or activity data for VCM production are available. ” (Reference Page 76 of the IPCC report located at: http://www.ipcc-nggip.iges.or.jp/public/2006gl/pdf/3_Volume3/V3_3_Ch3_Chemical_Industry.pdf )We appreciate your consideration of our explanations and your reply on these issues and to our

concerns on addressing future data validation messages.

Please contact me at 972-404-2411 or Frederick_fedri@oxy.com if you have any questions. *Additional calculation basis data can be supplied upon request using confidential business information (CBI) procedures. Very truly,

Frederick Fedri Principal Environmental Specialist Occidental Chemical CorporationAppendix A

Appendix B: