1 

## St. John, Virgin Islands **2002 Regional Haze**  **Base Year Modeling**  **Inventory SIP**

**Technical Support Documentation**

**June 19 ,**  **2012**2

**I. PREFACE**  This document is to support EPA's approval of a revision to the Virgin Islands’ State Implementation Plan (SIP ) which pertains to the following: Where applicable, 2002 modeling base ye ar inventory annual emissions for PM 2.5 , NOx and SO 2 for St. John, Virgin I sland (VI) area. Among the topics discussed below are the recent history and criteria for approval and E PA’s final recommendations.
**II. BACKGROUND**  On November 18, 2002, EPA designated the 2002 base year inventory as the inventory for SIP planning process to address the pollutants for the eight hour
- ozone, PM 2.5 and CO national ambient air quality

standard. Identifying the base year gives certainty to States, and the selection of 2002 harmonize d the date for EPA’s Consolidated Emissions Reporting rule (See 67 FR 39602) dated June 10, 2002.) that requires submission of the ozone, PM 2.5 and CO emission invent ories every

three years; 2002 is one of the required years for such updates. These requirements allow the EPA, based on the state’s progress in reducing emissions, to periodically reassess its policies and air quality standards and revise them as necessary. Most important, the 2002 ozone, new PM 2.5 and CO inventories will be used to develop and assess new control strategies that the states will need to submit in their attainment demonstration SIPs for the new national ambient air quality standards for ozo ne, PM 2.5 and CO. The base year inventory may also serve as part of statewide inventories for purposes of regional modeling in transport areas. The base ye ar inventory

play s an important role in modeling demonstrations for areas classified as nonattainment and outside transport regions. For the reasons stated above, ideall y EPA would therefore emphasize the importance and benefits of developing a comprehensive, current, and accurate 2002 ozone and PM 2.5 emission inventories
. **III. CRITERIA FOR APPROVAL**  There are general and specific components of an acceptable emission s inventory . In general, the State must submit a revision to its SIP and the emission inventory must meet the minimum requirements for reporting b y source category. Specificall y, the source requirements are detailed below. The Level I and II review process is used to determine that all components of the base ye ar inventory are present. The review also evaluates the level of supporting documentation provided by the State and assesses whether the emissions were developed according to current EPA or acceptable alternative guidance. The data quality is also evaluated. The Level III review process is outlined here and consists of 9 points that the inventory must3

adequatel y address. For a base ye ar emission inventory to be acceptable it must pass all of the following acceptance criteria: Adequate documentation must be provided that enabled the reviewer to determine the emission estimation procedures and the data sources used to develop the inventory
. **1. Evidence that the inventory was quality assured by the state and its implementation**  **documented. 2.**  **The point source inventory must be complete. 3.**  **Point source emissions must have been prepared or calculated according to the current EPA guid**  **ance. 4.**  **The area source inventory must be complete. 5.**  **The area source emissions must have been prepared or calculated according to the current EPA guidance.**  **6. Non**  **- road mobile emissions were prepared according to current EPA guidance for**  **all of the so urce categories.**  **8. The method (e.g., HPMS or a network transportation planning model) used to**  **develop VMT estimates must follow EPA guidance. The VMT development methods were adequately described and documented in the inventory report.**  **9. The MOBILE mo**  **del must be correctly used to produce emission factors for each of the vehicle classes.** 
**IV. DETAILED ACTION AND EVALUATION**  D rafts and final versions of the Emissions Inventory were provi d ed to Region 2 for the following documents and program area elements: Where applicable, 2002 base year inventory annual PM 2.5 , NOx and SO 2 emissions for the area
. **See Table s 1**  **- 3**  **below .**  This TSD contains a detail ed discussion and summary of the review conducted b y EPA for, where applicable, the 2002 base year inventory annual emissions for PM 2.5 , NOx and SO 2 the are a . **A. Details on**  **H ow**  **the Virgin Islands Satisf**  **ies Criteria 1 for the Quality Assurance**  **Plan**4

**Quality Assurance Plan Implementation** The Quality

Assurance (QA) plan was implemented for all portions of the invento ry . The QA plan included a QA/Quality control (QC) program for assessing data completeness and standard range checking. Critical data elements relative to the inventory sources were assessed for completeness. QA checks were performed relative to data co llection and analy sis, and double counting of emissions from point, area and mobile sources. QA/QC checks were conducted to ensure accuracy

of units, unit conversions, transposition of figures, and calculations. The reader is referred to Chapter II of D evelopment of the 2002 Regional Haze Area, Point, Nonroad Mobile and Onroad Mobile Source Emission Inventories for St. John, Virgin Islands , dated June 2010
. **The QA plan for the inventory was performed in accordance with**  **EPA Guidance.**  **1,2 ,3** 
**B. Details on H**  **ow the Virg**  **i n Islands**  **Satisfies Criteria 2 and 3 for the Point Source**  **Inventory Point Source Inventory**  St. Jo hn, VI inventory

includes point sources PM 2.5 , NOx and SO 2 emissions for the area.
. The inventory report describes how point source activity leve ls and their associated parameters are developed, and how the data are used to calculate emission estimates. The report reference s document for activity

level and emission factors used and provide s sample actual activity data and emissions factors . Infor mation on how c ontrol efficiencies are applied and the associated sample calculations with numerical values are provided
. Where applicable, annual PM 2.5 , NOx and SO 2 point source emissions are presented for the area
. P lant summary information on detailed plant levels is included in the inventory
. The reader is referred to Chapter III of Development of the 2002 Regional Haze Area, Point, Nonroad Mobile and Onroad Mobile Source Emission Inventories for St. John, Virgin Islands , dated June 2010
. **Thus, the point**  **inventory was developed**  **in accordance with section 5.3 of EPA**  **Guidance. 1,2**  **,3**
**C. Details on How**  **The Virgin Islands Satisfies**  **Criteria 4 and 5 for the Area Source Inventory**  **Area Source Inventory** The inventory

lists the source categories that are inclu ded in the area source inventory . Area source emissions are presented on a source category, county basis. Where applicable, annual emissions are provided for PM 2.5 , SO 2 and N Ox for the area . Inventory documentation includes emissions factors, activity lev els and sample calculations. Referenced information for the input values to equations is included. P oint source contributions have been correctly factored out of the area source category

totals where appropriate. C ontrol efficiency and rule penetration are5

correctly applied for source categories. The reader is referred to Chapter IVof Development of the 2002 Regional Haze Area, Point, Nonroad Mobile and Onroad Mobile Source Emission Inventories for St. John, Virgin Islands , dated June 2010
. **Thus, the a rea source**  **inventory was developed in accordance with**  **EPA Guidance.**  **1,2 ,3** 

**D. Details on How**  **The Virgin Islands Satisfies**  **Criteria 6**  **for Non Road Mobile Source Inventory**  **Commercial Marine Vessel Emissions** Commercial marine vesse l (CMV) emissions for PM 2.5 , NOx, and SO 2 and NH 3 are prepared b y EPA contractor . The inventory report relied on actual operational data and then used local activity parameters. From this information, emission estimates are prepared based on estimated activity by mode, engine power by

vessel, time in mode..etc. Where applicable, annual emissions are provided for PM 2.5 , NOx, and SO 2 for total combined nonroad mobile sources for the area s . CMV source emissions are presented on a source category basis
. The reader is referred to Chap ter V of Development of the 2002 Regional Haze Area, Point, Nonroad Mobile and Onroad Mobile Source Emission Inventories for St. John, Virgin Islands , dated June 2010. **CMV source emissions was**  **developed in accordance with EPA**  **Guidance. 1**  **, 2, 3** 

. **E. Details o**  **n How The Virgin Islands**  **Satisf ies**  **Criteria 8 and 9 for the Onroad Source Inventory**  **Onroad Mobile Source Inventory** The Virgin Islands’ mobile source inventory was developed by

using 2002 annual v ehicle m iles traveled (VMT) inventory from a surrogate area of Kauai , Hawaii by using VMT data from Kauai and population data from Kauai and St. Johns, VI t o develop VMT estimates by county, geographic component (urban, small urban and rural) and functional c lasses
. Mobile 6 m odel for PM 2.5 , NOx and SO 2 was u sed to generate emission factors for onroad vehicle emission estimates. The report also explains how Mobile 6 emission factors are used, in conjunction with VMT data, to estimate mobile source emissions for the inventoried areas. It provides the sources for the key inputs into the M obile model. Key assumptions are also included. The methods used to determine on
- road emission estimates are explained in the EPA’s Documentation f

or the Onroad NEI f

or Base Years 1970
- 2002 , dated January 2004
. Where applica ble, annual emissions are provided for PM 2.5 , NOx and SO 2 the are a . The breakdown of annual emissions by

highway vehicle classifications is included in the inventory
. **The inventory was developed in accordance with**  **EPA Guidance.**  **1,2 , 3** 6

**2018 Emissions Inve ntory**  Unfortunatel y, not enough is known about possible growth on St. John to use growth factors. Growth of population and sources may be restricted, as a result of the small size of the island and the large amount of land included in the National Park. There is not enough information available for the motor vehicle fleet on St. John, and projections based on vehicle turnover may be very different from reality

in an isolated location such as St. John and no interstate highway s to bring outside traffic through. Therefore , no growth factors were applied to the area, nonroad mobile and onroad mobile source inventories from base year 2002 to 2018
. **See 2018 Modeling inventory below**  **in Tables 1 -**  **3 .** 7

**Table 1: Sulfur Oxides**  **Emission s**  **from Point, Area and Mobile**  **Sources o n**  **St. John, Virgin**  **Islands (tons per year** **) Source Sector**  **Baseline 2002 2018 (with measures for RPG)**  **Point** 43.11 43.11 **Area** 0.05 0.05 **Non -**  **Road Mobile** 17.89 17.89 **On -**  **Road Mobile** 1.61 1.61 **Marine Vessels** 94.06 14.11 **Total 156.72**  **76.77**
**Table 2: Nitrogen Oxide**  **Emission s**  **from Point, Area and Mobile Sources on St. John,**  **Virgin Islands ( tons per year** **) Source Sector**  **Baseline 2002 2018 (with measures for RPG)**  **Point** 477.66 477.66 **Area** 3.69 3.69 **Non -**  **Road Mobile** 2.07 2.07 **On -**  **Road Mobile** 25.03 25.03 **Marine Vessels** 318.23 63.65 **Total 826.68**  **572.1**

**Table 3: Direct**  **Em ission**  **s of Particulate Matter**  **from Point, Area and Mobile Sources on**  **St. John, Virgin Islands (** **tons per year )**  **Source Secto r**  **Baseline 2002 2018 (with measures for RPG)**  **Point** 34.33 34.33 **Area** 38.32 38.32 **Non -**  **Road Mobile** 1.93 1.93 **On -**  **Road Mobile** 0.73 0.73 **Marine Vessels** 8.57 1.28 **Total 83.88**  **76.59**8 **Table 5: Emissions from HOVENSA (** **in tons per year** **) Sulfur Oxides**  **Nitrogen Oxides Particulate Matter**  **HOVENSA Base 2002** 12,778 26,362 2,207 **HOVENSA Future 2018** 9,318 21,331 2,1929

**Conclusion** Virgin Islands has a SIP that demonstrate s the requirements for emission inventory measures and repo rting are adequatel y met. To comply with the emission inventory requirements, the State must submit a complete inventory containing an implemented Quality Assurance Plan, point, area, on - road, and non
- road mobile source data, and accompanying support documentation
. **Recommendation EPA is approving this SIP submittal**  **because it meet**  **s the essential reporting requirements**  **for an Emission s**  **Inventory.**10

**Emission Inventory Guidance Documents** 1 Emission Inventory

Guidance for Implementation of o zone and Par ticulate Matter NAAQS and Regional Haze Regulation , September 2005 2 Ex ample Documentation Report for 1990 Base Year Ozone and Carbon Monoxide State Implementation Plan Emission Inventories , March 1992 3 Guidance on the Use of Models and Other Anal yses for Demonstration Attainment of Air Quality Goals for Ozone, PM2.5 and Regional Haze , dated April 2007