MEMORANDUM

DATE: August 12, 2010

SUBJECT: Update Emissions Data Used in Resi dual Risk Modeling for the Marine Tank Vessel Loading Operations Source Category

EPA Contract No.: EP-D-06- 118; EPA Project No.: 4-15 RTI Project No.: 0210426.004.015

FROM: Karen Schaffner, RTI International

TO: Stephen Shedd and Mary Tom Kissell, EPA

The purpose of this memorandum is to provide a update of emission data 1 used in estimating residual risk for the Marine Tank Vessel Loading Operations (MTVLO) source category for the October 2008 RTR proposal (73 FR 60432; Oct ober 10, 2008).

I. 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) (2) requires the Environmental Protection Agency (EPA) to develop technologybased standards for categories of industrial sources. In the second stage of the regulatory process, EPA is required under section 112(f)(2) to assess the health and environmental risks that remain after sources come into compliance with MACT.

As part of this second stage in the regula tory process, EPA is evaluating the risks remaining after implementation of the MTVLO MACT . In the current risk assessment analysis,

data from the 2005 NEI/NATA database for MTVLO were used.

II. Emissions Estimate for the MTVLO Source Category

The estimate of the number of facilities a nd the HAP emissions from the MTVLO source category have changed over time due to changes in the industry and the addition or closing of MTVLO at facilities. For example, in 1995 when the MTVLO MACT was promulgated, there were approximately 1,500 facilitie s that conducted MTVLO, and an analysis for calendar year (CY) 2000 showed that there were approximately 800 facilities that c onducted MTVLO. The progression over time of facilities and the emi ssions data for the MTVLO source category are

described below. The discussions include the MACT development (proposal and then promulgation in 1995), an analysis conducted fo r CY2000, the 2002 NEI dataset, and the current

2005 NEI/NATA data set.

1 Emissions Data Used in Residual Risk Modeli ng for the Marine Vessel Loading Source Category . K. Schaffner, RTI to D. Markwordt and M. Kissell, EPA. June 10, 2008 , Attachment to docket item EPA-HQ-OAR-2008-0026.1.2 A. MACT Development for MTVLO

Table 1 presents a summary of the estimates used during the development of the MACT

rule. The Waterborne Commerce Statistics Center (WCSC) database for the U.S. was used as the basis of the impacts analysis in the deve lopment of the MACT for MTVLO. The WCSC database contains detailed information on the types and quantities of commodities loaded and unloaded at U.S. ports, harbors, waterways, and canals. The analysis at proposal and promulgation of the MACT included all facilities in the source category.

Table 1. Data for MACT Development for MTVLO

No. of facilities Uncontrolled HAP emissions, Mg Controlled HAP emissions, Mg Avera g e emissions per facility, Mg/facility

Full MTVLO source category (area sources and major sources) 1500 8,000 1,400 0.97 Mg/fac

Valdez Marine Terminal 1 5,021 100 NA

Major sources (required to install MACT controls) 50 1,600 50 1.0 Mg/fac

Other sources (both Area, and Major sources subject to MACT) 1449 1,400 1,400 NA

All Major Sources with

MTVLO 300 Not calculated

Number of Facilities . For the source category, we estimated that there were approximately 1,500 facilities condu cting MTVLO (including petrol eum refineries) and the HAP emissions were 1,400 Mg. At proposal of the MTVLO MACT,, we estimated that 300 to 360 major source facilities were subject to the proposed MACT. 2, 3 At promulgation of the MTVLO MACT rule, we estimated that approximately 50 major source facilities would need to install controls but did not publish an esti mate of all the major sources that would be subject to the final rule. Between proposal and promulgation of the MTVLO MACT, we revised the rule to exclude MTVLO at refineries since they are covered by th e refinery rule (there were approximately 130 refineries at promulgation of the petroleum refinery rule at 40 CFR subpart CC, and 150 petroleum refineries today). Thus at promulgation of the MTVLO rule, the number of subject facilities (i.e., major sources) could be somewhat less than 300 to 360, how ever, to ensure that we don’t underestimate emissions, for this analys is we will assume that approximately 300 major source facilities in the MTVLO source category, consistent with the MACT development.

Uncontrolled Emissions Estim ates at MACT Promulgation . The uncontrolled emission estimates for marine vessel loading operations derived from the WCSC data base showed

2 59 FR 25004; May 13, 1994.

3 Calculation of a MACT Floor for Title III Rulemaking for Marine Vessel Loading Operations . T. Campbell, MRI, to D. Markwordt, U.S, EPA. September 30, 1993.3 approximately 8,000 Mg of HAP prior to implementation of the MACT. 4 (The uncontrolled emissions from the Valdez terminal in Alaska accounted for 5,000 Mg of these HAP.)

• 1,600 Mg of HAP were emitted from approximately 50 terminals, and

• 1,400 Mg of HAP from the remaining terminals.

Emissions Estimates Following Implementation of MACT . We estimated that 1,600 Mg of HAP are emitted from approximately 50 termin als required to install controls under the MTVLO MACT. Following implementation of MACT (ignoring the Valdez terminal 5 ), the

WCSC emissions for marine vess el loading operations was estimat ed to be 1,400 Mg of HAP. The average HAP emissions per facility was es timated to be 0.97 Mg HAP from MTVLO (i.e., 1,400 Mg divided by 1,500 facilities is 0.97 Mg/faci lity). The 1,400 Mg of HAP was estimated

as follows:

• 50 Mg of emissions from MACT contro lled terminals: 1,600 Mg of HAP was reduced by 97 percent MACT requirement to 50 Mg of emissions, i.e., 1,600 x (1- 0.97), and

• 1,400 Mg of HAP emitted from the remaining terminals.

B. Calendar Year 2000

For calendar year (CY) 2000, we conducted an analysis to determine the number of

facilities and the HAP emissions from the MT VLO source category. The WCSC database was also used for the CY2000 analysis. The analysis in 2000 included all facilities in the source category. For CY2000, there were approximately 800 facilities and the HAP emissions were 900 Mg, as shown in Table 2.

Table 2. Data for CY2000 MTVLO

No. of

facilities Uncontrolled HAP emissions, Mg Controlled HAP emissions, Mg Average emissions per facility, Mg/facility Full MTVLO source category 800 2,400 900 1.1 Mg/fac

Major sources (required to install MACT controls) 50 1,520 58 1.2 Mg/fac

Other sources (both Area, and Major sources subject to MACT) 750 845 845 NA

All Major sources 300 Not calculated Not calculated Not calculated

4 Technical Support Document for Proposed Standards: VOC/HAP Emissions from Marine Vessel Loading Operations . U.S. Environmental Protection Agency, Research Triangle Park, NC. EPA Publication No. EPA450/3-92/011a. May 1992.

5 Emissions from the VMT were estimated to be approximately 100 Mg, i.e., 5,000 Mg uncontrolled emissions reduced by 98 percent, is 100 Mg.4 Number of Facilities . Under this analysis, we estim ated for CY 2000 that there are approximately 800 terminals in the marine ve ssel loading source cate gory. Approximately 50 terminals (major sources) are required to control MTVLO emissions under the MACT requirements. This estimate was based on seve ral assumptions, including all terminals are collocated at major sources, the terminals are c ontiguous if collocated, a nd the terminals are bulk loading and thus included in the source category. Transportation of sealed containers are also likely included in the estimate of 800 terminals, ho wever this activity should not be part of the source category (and would not result in emissions).

Emissions Estimates for CY2000 . Under this analysis, we estimated from WCSC database for calendar year 2000 that there are 1,500 Mg of uncontrolled HAP emitted from approximately 50 terminals would need to install controls under the MACT. 6, 7 There are another 850 Mg of HAP that are emitted from th e remaining terminals. The total uncontrolled HAP emissions were estimated to be 2,400 Mg for the source category. On a controlled basis, considering application of MA CT control requirements, the total emissions from the source category were estimated to be 900 Mg of HA P for the 800 terminals. The average HAP emissions per facility is 1.1 Mg HAP (i.e., 900 Mg of HAP divided by 800 facilities is 1.1 Mg/facility).

• 50 Mg of emissions from MACT contro lled terminals: 1,500 Mg of HAP was reduced by 97 percent MACT requirement to 50 Mg of emissions, i.e., 1,500 x (1- 0.97), and

• 850 Mg of HAP emitted from the remaining terminals.

C. NEI Emissions Dataset for 2002

For the October 2008 RTR proposal, we used th e most recent data from EPA’s NEI (year 2002). The analysis based on the 2002 NEI included a subset of facilities in the MTVLO source category. There were 135 facilities and the MTVLO HAP emissions from the 2002 NEI were 230 Mg, as shown in Table 3.

6 Assessing Residual Risk for Ma rine Vessel Loading Operations . Memorandum from B. Riddle, Alpha-Gamma Technologies, Inc., to D. Markwordt, EPA/ESD. October 10, 2002.

7 Calendar Year 2000 HAP Emissions Estimates from Marine Vessel Loading. From B. Riddle, Alpha-Gamma Technologies, Inc. Table 2-3, Estimated HAP Emissions from Marine Vessel Loading Prior to the NESHAP, and Table 2-4, Estimated HAP Emissions from Marine Vessel Loading after Compliance with the NESHAP.5 Table 3. Data for 2002 NEI Dataset

No. of facilities Reported MTVLO HAP emissions, Mg Average emissions per facility, Mg/facility

2002 NEI data set 135 230 1.7 Mg/fac

Major sources in 2002 NEI (based on NEI identification as subject to MACT or current total facility emissions) 129 226 1.8 Mg/fac

Area sources in 2002 NEI 6 3.6 0.60 Mg/fac

Number of Facilities . The 2002 NEI HAP emissions data were used as the basis of the Residual Risk analysis for the initial Octobe r 2008 RTR proposal. The 2002 NEI database contained 135 facilities emitting 230 Mg (250 ton/yr) HAP. 8 (The 230 Mg includes the emissions from the Valdez, Alaska terminal with 5.5 Mg of emissions following controls.) The average HAP emissions per facility in the 2002 NEI dataset was 1.7 Mg HAP for MTVLO (i.e., 230 Mg divided by 135 facilities is 1.7 Mg/facility). There were 129 faciliti es identified as major sources in the dataset, with em issions of 226 Mg (the average HAP emissions per facility is 1.7 Mg/facility, i.e., 226 Mg divided by 129 facilities is 1.7 Mg/facility), and there were 6 facilities

that were identified as area sources of HA P and emissions are 3.6 Mg (the average HAP emissions per facility is 0.60 Mg/f acility, i.e., 3.6 Mg divided by 6 facilities is 0.60 Mg/facility).

D. NEI/NATA Emissions Dataset for 2005

Currently, we are using the most recent data from the NEI/NATA (year 2005). The analysis based on the 2005 NEI/NATA includes a subset of facilities in the MTVLO source category. The MTVLO HAP emissions from the 2005 NEI were 450 Mg and there are 223 facilities in dataset, as shown in Table 4.

Table 4. Data for 2005 NEI/NATA Dataset

Facilities with MTVLO No. of facilities Reported MTVLO HAP emissions, Mg Average emissions per facility, Mg/facility
2005 NEI data set 223 450 2.0 Mg/fac
Major sources in 2005 NEI (based on

N EI identification as subject to MACT or current total facility emissions) 152 380 2.5 Mg/fac

Area sources in 2005 NEI 71 64 0.90 Mg/fac

Number of Facilities . The 2005 NEI/NATA database contains 223 facilities with

MTVLO. The HAP emissions for MTVLO at these facilities are 450 Mg (490 ton) HAP. 9 The

8 NPRM Dataset for Marine Vessel Loading. For Oct ober 10, 2008, Proposal of Marine Vessel Loading Risk and Technology Review. Docket item No. EPA-HQ-OAR-2008-0008-0019.

9 NPRM Dataset for Marine Vessel Loading. For 2010 Re-Proposal of Marine Vessel Loading Risk and Technology Review.6 average HAP emissions per facility in the 2005 NEI/NATA dataset was 2.0 Mg HAP for MTVLO (i.e., 450 Mg divided by 223 facilities is 2.0 Mg/facility). There are 152 facilities identified as major sources in the dataset, wi th emissions of 380 Mg HAP (420 ton), and there

are 71 facilities that are identified as area sour ces of HAP and emissions are 64 Mg (70 ton).

E. Current Estimates for Major Source Facilities and Emissions

The data analyses conducted over time for the MTVLO source category have shown that

the number of facilities in the U.S. with MTVLO has declined over time. The data analysis in 1995 showed that there were approximatel y 1,500 facilities with MTVLO and by 2000, the

number of facilities had declined to 800 facilities. The average HAP emissions per facility value for the full source category data is typically 1 Mg/f acility, with 0.97 Mg/facility in 1995 and 1.1 Mg/facility in 2000.

Unfortunately, we do not have data on a consis tent basis over time to determine the major source facilities subject to this MACT standar d. The datasets based on the WCSC included all facilities in the source category. The later da tasets from the EPA NEI and NEI/NATA contain approximately half of the facilities in the source category but not all. Cu rrently, we believe there are 300 major source facilities with MTVLO subj ect to this MACT, based on information from MACT development (see section II.A). Of those, we identified 152 faciliti es in the most recent NEI. Thus we applied a ratio of 300/152 to emi ssions shown in Table 5 to estimate total major

source emissions. The emissions estimate for ma jor source facilities is 760 Mg (840 ton).

Table 5. Current Estimates for Major Source Fa cilities and Emissions Subject to MTVLO

MACT

Facilities with MTVLO No. of facilities MTVLO HAP emissions, Mg Avera g e emissions per facilit y in NEI, Mg/facility

Major Sources (Subject to MTVLO MACT) Major sources in 2005 NEI (based on

N EI identification as subject to MACT or current total facility emissions) 152 380 2.5 Mg/fac

Estimate for Total Major Sources 300 760 NA