### 9/13/2010

To: Docket – ID No. EPA-HQ-OAR-2010-0600

From: Elaine Manning, Sect or Based Assessment Group

Subject: Post Proposal Revisions for Mari ne Tank Vessel Loading Facilities Risk and Technology Assessment

The attached revisions were made to th e Marine Tank Vessel Loading Operations source category risk assessment which was included in the proposal for the Group I Polymers and Resins; Marine Vessel Load ing Operation; Mineral Wool Production; Pharmaceuticals Production; and Printing and Publishing Industry rulemaking issued on October 10, 2008. The updated Table 3.3-1 Summary of Emissions from the Marine Tank Vessel Loading Operations Source Ca tegory, Table 3.3-2 Summary of Source Category Level Risk for Marine Tank Ve ssel Loading Operations, and Table 3.3-3 Summary of Acute Refined Results for Marine Tank Vessel Loading Operations reflecting the changes are attached. The mo st significant change from the October 10, 2008 proposal is the change in the maximum individual risk (MIR). Based on updated

emission information obtained since the Oct ober 2008 proposal the ri sk results changed for the MIR and hazard index (HI). The ma ximum MIR for cancer changed from 1 at proposal to 20 for the current analysis. The maximum HI changed from 0.006 at proposal to 0.3 for the current an alysis. The screening acute value of 5 for glycol ethers

reduced to below 1 after the refined acute anal ysis was done. The next facility with an acute value of 3 for benzene became 0.96 (rounde d to 1) with the refined analysis. The attached Appendices 1 and 6 provide the supporting information for the changes.

We used a scaling factor of 3 to adjust for allowable emissions. Based on the scaling factor, the MIR based on MACT-allowabl e emissions is estimated to be 60-in-1- million, and the maximum HI value is 0.9.

In addition to the risk presented by th e source category alone as shown in the attached Summary of Source Category Level Risk table, additional analysis was performed to access the “facility-w ide” risk. The results of the residual risk associated with all categories at the know n facilities (facility-wide) ar e presented in the attached Appendix 6 “Detailed Risk Modeling Results “. We used the National Air Toxics Assessment (NATA) database for estimating faci lity-wide risks due to our lack of more recent facility-specific emissions data for so me of the source categories included in the facility-wide analyses. Additionally, b ecause we have not yet begun our thorough

residual risk review for most source categories, we are unable at this time to estimate allowable facility-wide emissions. Thus, our facility-wide analysis is based solely on

actual emissions.

The facility-wide MIR and HI available in Appendix 6 are based on emissions, as identified in the NATA, from all emissions s ources at the identified facilities. The

### maximum facility-wide risks are estimated to be a cancer MIR of 200 in a million and a noncancer HI of 4, which occur at different facilities. The source category contribution

to facilities with a 200 in a million risk is sm all at 10% (for both faci lities) with a source category MIR cancer risk of 20 in a million. The maximum source category noncancer HI is 0.3 for reproductive and the maximum facility-wide HI is 4 for respiratory (maximum source category and facility-wide HI values occur at different facilities). The facility with the maximum facility-wide HI of 4 (respiratory) has a source contribution

less than 1%.

### Table 3.3-1 Summary of Emissions from the Marine Tank Vessel Loading Operations Source Category

Prioritized Inhalation Dose-Response Value Identified by OAQPS b

HAP a Emissions (tpy) Number of

Facilities Reporting HAP (152 facilities in data set) Unit Risk

Estimate for

Cancer? Reference

Concentration

for Chronic

Noncancer? Health

Benchmark

Values for Acute

Noncancer? PBHAP?

Hexane 87 104 Υ Υ
Methyl Tert-Butyl Ether 62 12 Υ Υ Υ

Toluene 46 111 Υ Υ

Methanol 48 25 Υ Υ

Benzene 6 42 105 Υ Υ Υ Xylenes (Mixture of o, m, and p Isomers) 31 102 Υ Υ

1,3-Butadiene 27 5 Υ Υ Υ
Styrene 23 27 Υ Υ

Cumene 10 28 Υ Υ
Ethylene Dichloride 6 8 Υ Υ Υ
Naphthalene 8 20 Υ Υ Ethyl Benzene 5 47 Υ Υ
Trichloroethylene 3 4 Υ Υ Υ
Acrylonitrile 2 7 Υ Υ Υ
Tetrachloroethylene 2 8 Υ Υ Υ
Propylene Oxide 2 3 Υ Υ Υ
Vinyl Acetate 2 7 Υ Υ
Acetaldehyde 1 2 Υ Υ Υ

Chloroform 1 2 Υ Υ
Glycol Ethers 0.5 3 Υ Υ

2,2,4-Trimethylpentane 0.4 12
Methylene Chloride 0.4 1 Υ Υ Υ
Methyl Methacrylate 0.3 3 Υ Υ

Biphenyl 0.2 12 Υ

m-Xylene 0.2 2 Υ Υ

Phenol 0.2 16 Υ Υ

Aniline 0.2 2 Υ Υ Υ
Methyl Isobutyl Ketone 0.2 2 Υ
Ethylene Glycol 0.1 21 Υ
o-Xylene 0.09 2 Υ Υ
Ethyl Acrylate 0.08 2 Υ
2-Nitropropane 0.08 2 Υ Υ
Acrylic Acid 0.06 3 Υ Υ
Vinyl Chloride 0.04 1 Υ Υ Υ
1-Chloro-2,3-Epoxypropane 0.02 1 Υ Υ Υ
1,2-Epoxybutane 0.02 1 Υ

Carbon Tetrachloride 0.02 1 Υ Υ ΥPrioritized Inhalation Dose-Response Value Identified by OAQPS b

HAP a Emissions (tpy) Number of

Facilities Reporting HAP (152 facilities in data set) Unit Risk

Estimate for

Cancer? Reference

Concentration

for Chronic

Noncancer? Health

Benchmark

Values for Acute

Noncancer? PBHAP?

Cellosolve Solvent 0.01 1 Υ Υ Ethylene Glycol Monoethyl

Ether 0.007 1 Υ Υ

Cresols (mixed) 0.005 12 Υ
Dimethyl Formamide 0.006 1 Υ Υ
Formaldehyde 0.003 1 Υ Υ Υ

Chlorobenzene 0.002 1 Υ Υ
Hydrochloric Acid 0.001 1 Υ Υ

Diethanolamine 0.001 1 Υ Methylene Diphenyl Diisocyanate 0.001 1 Υ Υ

Propylene Dichloride 0.0006 1 Υ Υ
1,2,4-Trichlorobenzene 0.0006 1 Υ

Chlorine 0.0005 1 Υ Υ Diethylene Glycol Monoethyl Ether 0.0005 1 Υ

o-Cresol 0.0005 1 Υ

POM 71002 0.0002 2 Υ p-Xylene 0.0001 1 Υ Υ
Manganese & Compounds 0.00006 1 Υ
Lead & Compounds 0.00002 1 Υ Υ

Chromium 0.00001 1 Υ

Nickel 0.00000

9 1 Υ Υ

Arsenic 0.00000

6 1 Υ Υ

Cadmium Compounds 0.00000

3 1 Υ Υ

Mercury Compounds 0.00000

3 1 Υ Υ

Selenium Compounds 0.00000

2 1 Υ

Beryllium Compounds 0.00000

1 1 Υ Υ Υ

### Table 3.3-2. Summary of Source Category Leve l Risks for Marine Tank Vessel Loading Operations

Result HAP “Drivers”
Facilities in Source Category Number of Major Source Facilities Estimated to be in Source Category 300 n/a

Number of Facilities Identified in NEI and Modeled in post-NPRM Risk Assessment 152 n/a

Cancer Risks Maximum Individual Lifetime Cancer Risk (in 1 million) 20 benzene

Number of Facilities with Maximum Individual Lifetime Cancer Risk: Greater than or equal to 100 in 1 million 0 n/a Greater than or equal to 10 in 1 m illion 3 benzene, 1,3-butadiene, naphthalene Greater than or equal to 1 in 1 milli on 3 benzene, 1,3-butadiene, naphthalene

Chronic Noncancer Risks Maximum Reproductive Hazard Index 0.3 1,3-butadiene Number of Facilities with Maximu m Reproductive Hazard Index:

Greater than 1 0 n/a Acute Noncancer Screening Results

Maximum Acute Hazard Quotient 5 glycol ethers (REL)

Number of Facilities With Potential for Acute

Effects 2 glycol ethers, benzene

Acute Noncancer Refined Results Maximum Acute Hazard Quotient 1 benzene (REL)

Number of Facilities With Potential for Acute

Effects 0

Population Exposure Number of People Living Within 50 Kilometers

of Facilities Modeled 61,000,000 n/a

Number of People Exposed to Cancer Risk: Greater than or equal to 100 in 1 million 0 n/a Greater than or equal to 10 in 1 million 1,000 n/a Greater than or equal to 1 in 1 million 71,000 n/a Number of People Exposed to Reproductive Hazard Index : Greater than 1 0 n/a Estimated Cancer Incidence (excess cancer cases per year) 0.01 n/a

Contribution of HAP to Cancer Incidence 1,3-butadiene 59% n/a

benzene 21% n/a naphthalene 14% n/a acrylonitrile 4% n/a ethylene dichloride 2%

### Attachments: Appendix 1 Revised Em issions Inventory Support Memorandum Appendix 6 Detailed Risk Modeling Results Appendix 7 Acute Impacts Refined Analysis Figure