Regional NEPA Analysis of NOx Emissions from Potential Oil & Gas Development

1. Regional NEPA Analysis of NOx Emissions from Potential Oil & Gas Development Scott F. Archer USDI - Bureau of Land Management scott_archer@blm.gov March 11, 2004

2. Outline This presentation describes the Montana and Wyoming Powder River Basin Oil & Gas Air Quality Impact Assessments’: • Major Analytical Assumptions • Major Emission Sources • Analysis Methodology • Summary of Major Findings • Technical Support Document

3. NEPA Air Quality Impact Analyses • Key issues: Potential impacts to Standards, Increments, HAPs, visibility, atmospheric deposition • Thresholds: Legal limits or “best science” • Analysis and disclosure process (not decision) • Focus on greatest potential impacts • Affected Environment = Background • Reasonably Foreseeable Future Activities • No Action = Background + RFFA • Potential Direct impacts = “Alternative” • Potential Cumulative =No Action + “Alternative”

4. History • WY PRBO&G Project Air Quality Analysis began in June 2000 • Wyodak EIS was just completed • DM&E Railroad Expansion was underway • MT PRBO&G Project Air Quality Analysis began in April 2001 • For a variety of reasons, both the MT and WY PRBO&G DEIS’ were delayed until January 2002

5. History • Initial combined Air Quality modeling results became available in April 2002 • May 2002 Comments on both DEIS’ • The emissions inventory was updated through May 31, 2002 • Significant re-modeling completed December 2002 • Both the MT and WY PRBO&G FEIS’ were published January 2003

6. Major Analytical Assumptions Montana and Wyoming Study Area - New 5 State Domain (2.2 times larger than DM&E) Regional Meteorology - 1996 MM5 (36km) CALMET Grid size - 4km CALPUFF Receptor Grid near-field: 0.1 and 1km far-field: 1km, + lakes

10. Major Analytical Assumptions WyomingMontana Max, 50-100% electric, “NA” Max, electric booster,“NA” ~40,000 new CBM wells ~26,000 new CBM wells ~1,000 “booster” comps ~1,000 “field” comps ~300 “recip” comps ~100 “sales” comps ~ 3,000 conventional ~2,500 conventional 10 year “LOP” 20 year “LOP”

11. Major Emission Sources • Construction Activities • Road and pad clearing • Rig up and drilling • Rig down and testing • Operation Activities • 25 wells per field/booster compressor • 250 wells per sales/reciprocating compressor

12. Construction Activities • Access road and well pad construction (3 days) • Rig-up and drilling (4 days) • Rig-down and testing (5 days, including 1 day flaring) • Compressor pads Coal Bed Methane Drill Rig

13. Operating Emissions • Up to eight well pads per square mile, three wells per pad • 90% of wells drilled assumed to produce • Average 200 Mcf/day production over 10 - 20 year “life of project” Two 380 horsepower, CBM-fired reciprocal field compressors

14. MT Emission InventoryCoal Bed Methane Sources

15. MT Emission InventoryConventional Oil & Gas Sources

16. MT/WY Project Emissions

17. MT/WY New & RFFA Emissions

18. Analysis Methodology • MM5/CALMET and CALPUFF Models • Both near- and far-field analyses • Maximum HAP, incremental MLE and MEI cancer risks based on a “reasonable, but conservative” well pad and compressor scenario • Range of temporary generator impacts for power and pumping • Post-processing for Atmospheric Deposition (USDA-FS protocol) and Regional Haze (FLAG protocol)

19. MT/WY Receptor Locations

20. Summary of Major Findings Montana FEIS (Alt E - Preferred) - Comply with State/National Standards - Comply with PSD Class I and II Increments - Above lowest State’s 8-hr formaldehyde AACL; well within range - Within incremental cancer risk thresholds - Within Atmos. Deposition/ANC thresholds - Exceed 1.0 dv “just noticeable change” at seven mandatory federal PSD Class I Areas for 0 to 3 days per year (not likely to actually occur)

21. Summary of Major Findings Wyoming FEIS (Alt 2A - Preferred) - Comply with State/National Standards - Comply with PSD Class I and II Increments - Above lowest State’s 8-hr formaldehyde AACL; well within range - Within incremental cancer risk thresholds - Within Atmos. Deposition/ANC thresholds - Exceed 1.0 dv “just noticeable change” at ten mandatory federal PSD Class I Areas for 0 to 4 days per year (not likely to actually occur)

22. Summary of Major Findings Cumulative Montana, Wyoming and Other New & RFFA - Potential to exceed 24-hr PM2.5 and PM10 NAAQS - Potential to exceed 24-hr PM10 PSD Class II - Potential to exceed 24-hr PM10 PSD Class I (2 areas) - Potential to exceed Annual NO2 PSD Class I - Potential to exceed ANC thresholds (2 lakes) - Exceed 1.0 dv “just noticeable change” at all fourteen mandatory federal PSD Class I Areas for 2 to 32 days per year

23. What about Ozone?

26. For More Information Please feel free to contact: Scott F. Archer Senior Air Resource Specialist USDI – Bureau of Land Management National Science and Technology Center Denver Federal Center, Building 50 P.O. Box 25047 Denver, Colorado 80225-0047 USA +1.303.236.6400 scott_archer@blm.gov

28. Northern San Juan Basin Environmental Impact Statement for Coalbed Methane Development 3/1/2004

29. Existing Oil and Gas Development in the San Juan Basin

31. Projected Timeline * … * Schedule is dependent upon NOA approval and completion of air quality coordination.

32. For More Information Scott F. Archer Senior Air Resource Specialist USDI-Bureau of Land Management National Science and Technology Center Denver Federal Center, Building 50 P.O. Box 25047, ST-133 Denver, Colorado 80225-0047 303.236.6400 303.236.3508 Fax scott_archer@blm.gov