MEMORANDUM

DATE: August 12, 2010

SUBJECT: Update Emissions Data Used in Residual 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 emiss ion data 1 used in estimating residual risk for the Marine Tank Vessel Load ing Operations (MTVLO) source category for the October 2008 RTR proposal (73 FR 60432; Octob er 10, 2008).

I. BACKGROUND

Section 112 of the Clean Air Act (CAA) establishes a two -stage regulatory process to address emissions of hazardous air pollutants (HAPs) from stationary sources. In the first stage, section 112(d) (2) requires the Environmental Protection Agen cy (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 t he health and environmental risks that remain after sources come into compliance with MACT.

As part of this second stage in the regulatory process, EP A 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 and the HAP emissions from the MTVLO source category have changed over time due to changes in the indus try and the addition or closing of MTVLO at facilities. For example, in 1995 when the MTV LO MACT was promulgated, there were approximately 1,500 facilities that conducted MTVLO, an d an analysis for calendar year (CY) 2000 showed that there were approximately 800 facilities that conducted MTVLO. The progression over time of facilities and the emissions data for the MTVLO source category are described below. The discussions include the MACT develop ment (proposal and then promulgation in 1995), an analysis conducted for CY2000, the 2002 N EI dataset, and the current

2005 NEI/NATA data set.

1 Emissions Data Used in Residual Risk Modeling for the Marine Ves sel Loading Source Category . K. Schaffner, RTI to D. Markwordt and M. Kissell, EPA. June 10, 2008, At tachment 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 (W CSC) database for the U.S. was used as the basis of the impacts analysis in the development of the MACT for MTVLO. The WCSC database contains detailed information on the types and qua ntities of commodities loaded and unloaded at U.S. ports, harbors, waterways, and canals. T he 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 Average 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

O ther 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 w ere approximately 1,500 facilities conducting MTVLO (including petrol eum refineries) and the HAP emissions were 1,400 Mg. At proposal of the MTVLO MAC T,, we estimated that 300 to 360 major source facilities were subject to the proposed MA CT. 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 estimate 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 the refine ry rule (there were approximately 130 refineries at promulgation of the petroleum refinery ru le 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, however, to ensure that we don’t underestimate emissions, for this analysis we will assume that approximately 300 major source facilities in the MTVLO source category, consi stent with the MACT development.

Uncontrolled Emissions Estimates at MACT Promulgation . The uncontrolled emission estimates for marine vessel loading operations derived fr om 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 f or 5,000 Mg of these HAP.)

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

• 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 terminals require d to install controls under the MTVLO MACT. Following implementation of MACT (ignor ing the Valdez terminal 5 ), the WCSC emissions for marine vessel loading operations wa s estimated to be 1,400 Mg of HAP. The average HAP emissions per facility was estimated to b e 0.97 Mg HAP from MTVLO (i.e., 1,400 Mg divided by 1,500 facilities is 0.97 Mg/facility). The 1,400 Mg o f HAP was estimated

as follows:

• 50 Mg of emissions from MACT controlled terminals: 1,600 M g 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 de termine the number of

facilities and the HAP emissions from the MTVLO source category. The WCSC database was also used for the CY2000 analysis. The analysis in 2000 include d all facilities in the source category. For CY2000, there were approximately 800 faciliti es 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 fr om Marine Vessel Loading Operations . U.S. Environmental Protection Agency, Research Tr iangle Park, NC. EPA Publication No. EPA450/3-92/011a. May 1992.

5 Emissions from the VMT were estimated to be approxim ately 100 Mg, i.e., 5,000 Mg uncontrolled emissions reduced by 98 percent, is 100 Mg.4

Number of Facilities . Under this analysis, we estimated for CY 2000 that the re are approximately 800 terminals in the marine vessel loading source category. Approximately 50 terminals (major sources) are required to control MTVLO e missions under the MACT requirements. This estimate was based on several assu mptions, including all terminals are collocated at major sources, the terminals are contiguous if collocated, and the terminals are bulk loading and thus included in the source category. Transport ation of sealed containers are also likely included in the estimate of 800 terminals, however thi s 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 u ncontrolled HAP emitted from approximately 50 terminals would need to install controls un der the MACT. 6, 7 There are another 850 Mg of HAP that are emitted from the remaining terminals. The total uncontrolled HAP emissions were estimated to be 2,400 Mg for the source c ategory. On a controlled basis, considering application of MACT control requirements, the total emissions from the source category were estimated to be 900 Mg of HAP for the 800 ter minals. 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 controlled terminals: 1,500 M g 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 the 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 Marine 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 Mari ne 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 200 2 NEI (based on NEI identification as subject to MACT or current total facility emissions) 129 226 1.8 Mg/fac

Area sources in 200 2 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 October 2008 RTR pro posal. 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 f acilities identified as major sources in the dataset, with emissions of 226 Mg (the aver age HAP emissions per facility is 1.7 Mg/facility, i.e., 226 Mg divided by 129 facilities is 1.7 Mg/facil ity), and there were 6 facilities

that were identified as area sources of HAP and emissio ns are 3.6 Mg (the average HAP emissions per facility is 0.60 Mg/facility, i.e., 3.6 Mg di vided 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 N EI/NATA (year 2005). The analysis based on the 2005 NEI/NATA includes a subset of fac ilities in the MTVLO source category. The MTVLO HAP emissions from the 2005 NEI w ere 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 so urces in 2005 NEI (based on NEI 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 facili ties are 450 Mg (490 ton) HAP. 9 The

8 NPRM Dataset for Marine Vessel Loading. For Octob er 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 dat aset 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, with emissi ons of 380 Mg HAP (420 ton), and there

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

E. Current Estimates for Major Source Facilities and Emissi ons

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

the number of facilities in the U.S. with MTVLO has de clined over time. The data analysis in 1995 showed that there were approximately 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/faci lity, with 0.97 Mg/facility in 1995 and 1.1 Mg/facility in 2000.

Unfortunately, we do not have data on a consistent basis over time to determine the major source facilities subject to this MACT standard. The data sets based on the WCSC included all facilities in the source category. The later dataset s from the EPA NEI and NEI/NATA contain approximately half of the facilities in the source cate gory but not all. Currently, we believe there are 300 major source facilities with MTVLO subject to this MACT, based on information from MACT development (see section II.A). Of those, we i dentified 152 facilities in the most recent NEI. Thus we applied a ratio of 300/152 to emissions shown i n Table 5 to estimate total major source emissions. The emissions estimate for major so urce facilities is 760 Mg (840 ton).

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

MACT

Facilities with MTVLO No. of facilities MTVLO HAP emissions, Mg Average emissions per facility in NEI, Mg/facility

Major Sources (Subject to MTVLO MACT) Major sources in 2005 NEI (based on NEI identification as subject to MACT or current total facility emissions) 152 380 2.5 Mg/fac

Estimate for Total Major Sources 300 760 NA