Conformity Adequacy Review: Region 8

State Implementation Plans (SIP) Submissions that EPA has Found Adequate or Inadequate
Region 8: Colorado, Montana, North Dakota, South Dakota, Utah, and Wyoming

For more information about adequacy review, return to the main adequacy page.

Contact: Gregory Lohrke at 303-312-6396 Lohrke.gregory@epa.gov
U.S. EPA Region 8, 1595 Wynkoop St., Denver, Colorado 80202.

Colorado
Area	Pollutant	SIP Submission	Finding (date budgets apply)	Additional Information/ Comments
Aspen	PM10	maintenance plan	Adequate (6/11/2012) Letter FR Notice	Budgets found adequate through the adequacy review process.
Aspen	PM10	maintenance plan	Adequate (9/4/2002) Letter FR Notice	Budgets found adequate through the adequacy review process.
Canon City	PM10	maintenance plan	Adequate (8/17/2011) Letter FR Notice	Budgets found adequate through the adequacy review process.
Canon City	PM10	maintenance plan	Adequate (7/31/2000) FR Notice	Budgets found adequate through SIP approval process.
Colorado Springs	carbon monoxide	limited maintenance plan	Adequate (8/17/2011) Letter FR Notice	Budgets found adequate through the adequacy review process.
		maintenance plan 1998-2009 budgets	Inadequate (4/29/1999)	Determination made under old process
		maintenance plan 2010 budget and beyond	Adequate (4/29/1999)	Determination made under old process
Denver	2008 8-hour ozone	reasonable further progress	Adequate (6/8/2023) Letter (pdf) (219.08 KB, May 3, 2023) FR Notice	Budgets found adequate through the adequacy review process.
	2008 8-hour ozone	attainment plan	Adequate (4/2/2018) Letter FR Notice	Budgets found adequate through the adequacy review process
	1997 8-hour ozone	attainment plan	Adequate (3/19/2010) Letter FR Notice	Budgets found adequate through the adequacy review process.
	pm10	maintenance plan	Adequate (6/28/2007) Letter FR Notice	Budgets found adequate through the adequacy review process.
	pm10	maintenance plan	Adequate (10/29/2001) Letter FR Notice	Budgets found adequate through the adequacy review process.
	carbon monoxide	maintenance plan	Adequate (6/28/2007) Letter FR Notice	Budgets found adequate through the adequacy review process.
	carbon monoxide	maintenance plan	Adequate (8/18/2000) Letter FR Notice	Budgets found adequate through the adequacy review process.
Fort Collins	carbon monoxide	limited maintenance plan	Adequate (6/11/2012) Letter FR Notice	Budgets found adequate through the adequacy review process.
Fort Collins	carbon monoxide	maintenance plan	Adequate (1/15/2003) Letter FR Notice	Budgets found adequate through the adequacy review process.
Greeley	carbon monoxide	limited maintenance plan	Adequate (8/17/2011) Letter FR Notice	Budgets found adequate through the adequacy review process.
Greeley	carbon monoxide	maintenance plan	Adequate (1/20/2004) Letter FR Notice	Budgets found adequate through the adequacy review process.
Lamar	PM10	second maintenance plan	adequate 10/20/2014 79 FR 59767 printed 10/03/2014	Budgets found adequate through the adequacy review process
Lamar	PM10	maintenance plan	Adequate (11/12/2002) Letter FR Notice	Budgets found adequate through the adequacy review process.
Longmont	carbon monoxide	maintenance plan	Adequate (6/28/2007) Letter FR Notice	Budgets found adequate through the adequacy review process.
Longmont	carbon monoxide	maintenance plan	Inadequate (5/14/1999)	Determination made under old process
Pagosa Springs	PM10	maintenance plan	Adequate (8/17/2011) Letter FR Notice	Budgets found adequate through the adequacy review process.
Pagosa Springs	PM10	maintenance plan	Adequate (8/18/2000) Letter FR Notice	Budgets found adequate through the adequacy review process.
Steamboat Springs	PM10	second maintenance plan	adequate 10/20/2014 79 FR 59767 printed 10/03/2014	Budgets found adequate through the adequacy review process.
Steamboat Springs	PM10	maintenance plan	Adequate (11/12/2002) Letter FR Notice	Budgets found adequate through the adequacy review process.
Telluride	PM10	maintenance plan	Adequate (8/17/2011) Letter FR Notice	Budgets found adequate through the adequacy review process.
Telluride	PM10	maintenance plan	Adequate (8/18/2000) Letter FR Notice	Budgets found adequate through the adequacy review process.
Montana
Area	Pollutant	SIP Submission	Finding (date budgets apply)	Additional Information/ Comments
Missoula	PM 10	maintenance plan	Adequate (10/12/2018) Letter (Missoula PM10 Limited Maintenance Plan) (pdf) (903.64 KB, July 23, 2018) FR Notice (printed 9/27/2018) 83 FR 48715	Budgets found adequate through the adequacy review process.
	carbon monoxide	maintenance plan	Adequate (11/13/2017 )82 FR 43180 printed 9/14/2017)	Budgets found adequate through the SIP approval process.
	carbon monoxide	maintenance plan	Adequate (6/16/2006) Letter FR Notice (PDF)(2 pp, 141 K, published June 1, 2006, About PDF)	Budgets found adequate through the adequacy review process.
Utah
Area	Pollutant	SIP Submission	Finding (date budgets apply)	Additional Information/ Comments
Ogden	carbon monoxide	maintenance plan	Adequate (6/10/2005) Letter FR Notice (PDF)(2 pp, 144 K, published May 26, 2005, About PDF)	Budgets found adequate through the adequacy review process.
Ogden	carbon monoxide	maintenance plan	Adequate (4/29/1999)	Determination made under old process
Provo (Utah County)	carbon monoxide	attainment demonstration	Adequate (8/4/2004) Letter FR Notice (PDF)(1 pp, 138 K, published July 20, 2004, About PDF)	Budgets found adequate through the adequacy review process.
	PM10	attainment demonstration (2010 & 2020 budgets)	Adequate (10/16/2002) Letter FR Notice	Budgets found adequate through the adequacy review process.
	carbon monoxide	attainment demonstration	Inadequate (5/14/1999)	Determination made under old process
Salt Lake City Area	carbon monoxide	maintenance plan	Adequate (6/15/2005) Letter FR Notice (PDF)(1 pp, 139 K, published May 31, 2005, About PDF)	Budgets found adequate through the adequacy review process.
Utah portion of Logan UT-ID Area	PM2.5	attainment demonstration	Adequate (9/28/2015) FR Notice(published September 11, 2015)	Budgets found adequate through the adequacy review process

Conformity Adequacy Review: Region 8

State and Local Transportation