Oil & Gas Emissions Workgroup: About

Significant air pollutant emissions come from production of Oil and Gas (O&G) from wells located on state-regulated and tribal lands, as well as from the interconnected gathering networks interlacing the WRAP region.  These emissions result from operation of an extensive fleet of field equipment and an array of processing plants, operating continuously across the West.  These field operations include exploration, production, and gathering activities.

The Oil & Gas Emissions Workgroup was formed to look at air pollution issues resulting from these Exploration & Production (E&P) operations in the Western United States. The issues include quantifying emission inventories from stationary and mobile equipment operated as part of these O&G field operations, looking at environmental impacts stemming from these emissions (Regional Haze, Ozone, Rural PM, Greenhouse Gasses and etc.) and exploring a variety of other initiatives to assess, evaluate and control the problems resulting from operations in this Industry sector.

Historically emissions from large Stationary Point Sources processing this energy for the oil and gas fuels markets were pretty well quantified through existing Regulatory Agency permitting programs, but quite a number of pieces of smaller O&G field equipment (compressor engines, drill rigs, heaters, dehydrators, flares and etc) traditionally fell below Agency permitting thresholds.  Although individually emissions from this field equipment could be considered minor, with increasing energy demand and continuing oil and gas field development the cumulative totals for O&G basins, producing states and the WRAP region as a whole were thought to present an entirely different picture.  But prior to WRAP involvement, present and future Area Source emissions from western field oil and gas production operations were generally incompletely quantified.

The WRAP recognized this deficiency and formed the Oil and Gas Workgroup to look more closely at this industry and take steps to address the deficiencies.  In late 2005 the WRAP completed the Phase I O&G emission inventory project to estimate for the first time, regional emission totals from these field operations.  As a “first cut” Phase I had a number of uncertainties identified, thus the workgroup subsequently initiated the Phase II project, completed in Fall 2007, to more fully characterize the O&G Field Operations emissions.  These WRAP inventories identified over 100,000 TPY of NOx emissions in the WRAP region which had not previously been included in regional air quality assessment, as well as significant totals of other air pollutant species (VOC’s primarily) critical in the evaluation of Regional Haze and other air quality management issues.

Members of the Independent Petroleum Association of Mountain States (IPAMS) felt that still more improvement in the accuracy of these emission estimates was needed and available.  So in late 2007 IPAMS initiated a Phase III regional oil and gas emission inventory project funded by their organization.  The project was undertaken in conjunction with the WRAP to assure that the products from Phase III were widely distributed among non-industry stakeholders (State/Local Agencies, Tribal Air Programs, Federal Land Managers, Environmental Groups and EPA).  This wider participation was viewed as necessary to assure review and feedback such that the final inventories were understood and more universally accepted by those parties interested in and affected by O&G development in the Intermountain West.

Other Oil & Gas Information

CENRAP O&G Report (11/13/08) PDF (7 MB)
CENRAP identified the need to improve the oil and gas area source inventories for the 2002 base year and 2018 future year for the entire CENRAP region, encompassing the oil- and gas producing states of Texas, Louisiana, Oklahoma, Arkansas, Kansas and Nebraska. This is being driven by the high levels of oil and gas production activity that occur at hundreds of thousands of individual well sites, the large fleet of equipment that supports this activity, and the potential for this equipment to significantly contribute to emissions of NOx, VOC, SOx, greenhouse gases (GHG) and other pollutants in the region. Following their work for the WRAP, CENRAP contracted with ENVIRON to provide improved input information and methodology descriptions to update the CENRAP inventories. This work consisted of three principal tasks:

1. Identification of major CENRAP basins: the objective of this task was to generate oil and gas production statistics for all of the major geological basins in the CENRAP domain to determine which are the “major” basins. Major basins are those basins ranked highest by production of gas, oil or by active well counts.
2. Literature review and limited industry survey: the objective of this task was to gather input data used to calculate emissions from a wide variety of source categories associated with oil and gas exploration, production, transmission and gathering activities by reviewing published literature and studies on oil and gas emissions and equipment, and by conducted a limited industry survey to gather information about specific source categories in specific basins.
3. Develop recommendations: the objective of this task, and the subject of this report, was to synthesize the information gathered in Tasks 2 and 3 and recommend input data and methodologies to improve CENRAP’s oil and gas area source inventories for the 2002 base year and 2018 future year projections.

These tasks and their results are described in detail in this report.

EPA 2008 Sector Report PDF (11.3 MB)
The EPA has produced their 2008 Sector Report providing information on the environmental performance of some of America’s industrial sectors. One of the sectors covered in this report is the Oil & Gas Sector, and one of the resources EPA references in analyzing the air emissions from this sector is the state by state data covered by the WRAP’s O&G Emission Inventories. The discussion on the O&G Sector begins on Page 78 of the Report, hyperlinked from the report Table of Contents.

Upcoming Meetings & Calls