Appendix 1 Emissions Inventory Support MemorandumPolymers and Resins I1 MEMORANDUM

TO: Anne Pope, EPA

FROM: Darcy Wilson, ERG

DATE: July 19, 2010

SUBJECT: Emissions Data Used in Residual Risk Modeling: Polymers and Resins I

The purpose of this memorandum is to provide information on the RTR database used in estimating residual risk for four Polymers and Resins I Maximum Achievable Control Technology (MACT) source categories—Epichl orohydrin Elastomers Production, Nitrile Butadiene Rubber Production, Polybutadien e Rubber Production, and Styrene Butadiene

Rubber and Latex Production.

BACKGROUND

Section 112 of the Clean Air Act (CAA) establ ishes a two-stage regu latory process to address emissions of hazardous air pollutants ( HAPs) from stationary sources. In the first stage, section 112(d) requires the Environmental Protecti on Agency (EPA) to develop technology-based standards for categories of industrial sour ces. In the second stage, known as the residual risk stage, section 112( f)(2) requires EPA to a ssess the health and

environmental risks that remain after sour ces come into compliance with MACT. If

additional risk reductions are ne cessary to protect public health with an ample margin of safety or to prevent adverse environmenta l effects, EPA must develop standards to address these remaining risks. As part of this second stage, data were gathered to assess the residual risks from the four Polymers and Resins I MACT source categories.

EMISSIONS DATA USED IN RESIDUAL RISK MODELING

Information collected from industry served as the starting point for these assessments. This information was also incorporated into the 2002 National Emissions Inventory (NEI) by assigning the emissions estimate s to the specific process MACT codes 1 within the NEI (1311, 1321, 1325, and 1339). The 2002 NEI data for Polymers and Resins I were released through an Advanced Notice of Proposed Rulemaking (ANPRM) in March of 2007, where NEI revisions for facilities in the MACT source cate gories were solicited from State and local agencies, industry repres entatives, and EPA. The revisions that were provided to EPA were incorporated into the 2005 NEI prior to the initial NATA modeling.

1 Assigning data with MACT codes allows EPA to determine reductions attributable to the MACT program. The NEI associates MACT codes corresp onding to MACT source categories with stationary major and area source data.2 Epichlorohydrin Elastomers Production

Risks associated with the f acility covered by the Epichlor ohydrin Elastomers Production

MACT standard were modeled in the initia l 2005 NATA risk assessment in June of 2009. EPA reviewed the results of this analysis, and performed an in-depth review of the NEI data set for the source category. EPA also in corporated information received in response to an industry Information Collection Request (ICR), and evaluated th e facility-wide risks for Epichlorohydrin Elastomers Production us ing the 2005 NEI data and risk assessment

results that were released in the 2005 NATA Risk Preview with State and local agencies

in June of 2010. Revisions were made to the emissions estimates for the facility based on these analyses and updated information. Thes e revisions were included in the risk analyses, and will be reflected in the final NATA risk assessment.

Nitrile Butadiene Rubber Production

Risks associated with the f acility covered by the Nitril e Butadiene Rubber Production

MACT standard were modeled in the initia l 2005 NATA risk assessment in June of 2009. EPA reviewed the results of this analysis, and performed an in-depth review of the NEI data set for the source category. EPA also in corporated information received in response to an industry ICR, and evaluated the fac ility-wide risks for Nitrile Butadiene Rubber Production using the 2005 NEI data and risk asse ssment results that were released in the

2005 NATA Risk Preview with State and local agencies in June of 2010. Revisions were

made to the locational coordina tes and emissions estimates for the facility based on these analyses and updated information, and closed facilities, minor sources, and sources that no longer manufacture nitrile bu tadiene rubber were identified. These revisions were included in the risk analyses, and will be re flected in the final NATA risk assessment.

Polybutadiene Rubber Production

Risks associated with facilities covere d by the Polybutadiene Rubber Production MACT

standard were modeled in the initial 2005 NAT A risk assessment in June of 2009. EPA reviewed the results of this analysis, and pe rformed an in-depth review of the NEI data set for the source category. EPA also evalua ted the facility-wide risks for Polybutadiene Rubber Production using the 2005 NEI data a nd risk assessment re sults that were

released in the 2005 NATA Risk Preview with State and local agencies in June of 2010.

Revisions were made to the emissions estimat es for one facility based on these analyses.

These revisions were included in the risk an alyses, and will be reflected in the final

NATA risk assessment.

Styrene Butadiene Rubber and Latex Production

Risks associated with facilities covere d by the Styrene Butadiene Rubber and Latex

Production MACT standard were modeled in the initial 2005 NATA risk assessment in

June of 2009. EPA reviewed the results of this analysis, and performed an in-depth

review of the NEI data set for the source ca tegory. EPA also evaluated the facility-wide risks for Styrene Butadiene Rubber and La tex Production using th e 2005 NEI data and3 risk assessment results that were released in the 2005 NATA Risk Pr eview with State and local agencies in June of 2010. Revisions ma de based on these analyses consisted of

identification of closed facilities. These revisi ons were included in the risk analyses, and

will be reflected in the final NATA risk assessment.