YELLOWTAIL, MT · Big Horn County

YELLOWTAIL DAM GC SYSTEM Water System

Current status

No open violations on record as of July 4, 2026.

This system's next federally required Consumer Confidence Report is due July 1, 2027, under the EPA's revised reporting rule.

Data sourced from the EPA ECHO database (SDWA bulk download), last refreshed July 4, 2026. This is a record-keeping and public-information tool — it does not replace Montana’s official records. Always confirm current status with Montana before making decisions based on this information.

System facts

System ID (PWSID): MT0002514
System type: Community Water System
Population served: 125
Service connections: 50
Ownership: federal government
Water source: groundwater (wells)

Violation history

Lead Consumer Notice
—
Lead and Copper Rule
December 30, 2024 – February 12, 2025
Resolved
Consumer Confidence Report Complete Failure to Report
—
Consumer Confidence Rule
July 1, 2023 – July 10, 2023
Resolved
Monitoring, Regular
—
Nitrate-Nitrite
January 1, 2017 – December 31, 2017
Resolved
Lead Consumer Notice
—
Lead and Copper Rule
December 30, 2015 – February 1, 2016
Resolved
Monitoring, Regular
—
Nitrate-Nitrite
January 1, 2013 – December 31, 2013
Resolved
Consumer Confidence Report Inadequate Reporting
—
Consumer Confidence Rule
October 1, 2012 – February 4, 2014
Resolved
Consumer Confidence Report Complete Failure to Report
—
Consumer Confidence Rule
July 1, 2012 – February 4, 2014
Resolved
Monitoring, Regular
—
Asbestos
January 1, 2011 – December 31, 2013
Archived
Lead Consumer Notice
—
Lead and Copper Rule
January 1, 2010 – February 16, 2016
Resolved
Consumer Confidence Report Complete Failure to Report
—
Consumer Confidence Rule
July 1, 2007 – July 31, 2008
Resolved
Monitoring, Regular
—
Nitrate-Nitrite
January 1, 2006 – December 31, 2006
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
October 1, 2005 – October 31, 2005
Resolved
Consumer Confidence Report Complete Failure to Report
—
Consumer Confidence Rule
July 1, 2002 – October 2, 2003
Resolved
Monitoring, Regular
—
Dalapon
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Di(2-ethylhexyl) adipate
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
OXAMYL
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Simazine
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Di(2-ethylhexyl) phthalate
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Picloram
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Aldicarb sulfoxide
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Aldicarb sulfone
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Carbofuran
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Aldicarb
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Atrazine
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
LASSO
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Heptachlor
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
2,4-D
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
HEXACHLOROBENZENE
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Benzo(a)pyrene
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Pentachlorophenol
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Chlordane
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
1,2,4-Trichlorobenzene
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
cis-1,2-Dichloroethylene
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Xylenes, Total
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
p-Dichlorobenzene
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
trans-1,2-Dichloroethylene
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
1,2-Dichloroethane
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
1,1,1-Trichloroethane
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Carbon tetrachloride
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
1,2-Dichloropropane
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Trichloroethylene
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Tetrachloroethylene
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Benzene
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
DICHLOROMETHANE
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Arsenic
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Thallium, Total
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Antimony, Total
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Selenium
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Chromium
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Beryllium, Total
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Mercury
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Cadmium
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Barium
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Endrin
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
BHC-GAMMA
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Regular
—
Methoxychlor
January 1, 2002 – December 31, 2004
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
July 1, 1997 – July 31, 1997
Resolved
Monitoring, Routine Major (TCR)
—
Coliform (TCR)
July 1, 1994 – July 31, 1994
Resolved

Resolved addressed and confirmed by the stateArchived closed in EPA's records (typically due to age or a data correction)

Period	Violation	Contaminant / rule	Health-based	Status
December 30, 2024 – February 12, 2025	Lead Consumer Notice	Lead and Copper Rule	—	Resolved
July 1, 2023 – July 10, 2023	Consumer Confidence Report Complete Failure to Report	Consumer Confidence Rule	—	Resolved
January 1, 2017 – December 31, 2017	Monitoring, Regular	Nitrate-Nitrite	—	Resolved
December 30, 2015 – February 1, 2016	Lead Consumer Notice	Lead and Copper Rule	—	Resolved
January 1, 2013 – December 31, 2013	Monitoring, Regular	Nitrate-Nitrite	—	Resolved
October 1, 2012 – February 4, 2014	Consumer Confidence Report Inadequate Reporting	Consumer Confidence Rule	—	Resolved
July 1, 2012 – February 4, 2014	Consumer Confidence Report Complete Failure to Report	Consumer Confidence Rule	—	Resolved
January 1, 2011 – December 31, 2013	Monitoring, Regular	Asbestos	—	Archived
January 1, 2010 – February 16, 2016	Lead Consumer Notice	Lead and Copper Rule	—	Resolved
July 1, 2007 – July 31, 2008	Consumer Confidence Report Complete Failure to Report	Consumer Confidence Rule	—	Resolved
January 1, 2006 – December 31, 2006	Monitoring, Regular	Nitrate-Nitrite	—	Resolved
October 1, 2005 – October 31, 2005	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
July 1, 2002 – October 2, 2003	Consumer Confidence Report Complete Failure to Report	Consumer Confidence Rule	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Dalapon	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Di(2-ethylhexyl) adipate	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	OXAMYL	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Simazine	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Di(2-ethylhexyl) phthalate	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Picloram	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Aldicarb sulfoxide	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Aldicarb sulfone	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Carbofuran	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Aldicarb	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Atrazine	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	LASSO	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Heptachlor	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	2,4-D	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	HEXACHLOROBENZENE	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Benzo(a)pyrene	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Pentachlorophenol	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Chlordane	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	1,2,4-Trichlorobenzene	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	cis-1,2-Dichloroethylene	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Xylenes, Total	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	p-Dichlorobenzene	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	trans-1,2-Dichloroethylene	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	1,2-Dichloroethane	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	1,1,1-Trichloroethane	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Carbon tetrachloride	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	1,2-Dichloropropane	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Trichloroethylene	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Tetrachloroethylene	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Benzene	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	DICHLOROMETHANE	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Arsenic	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Thallium, Total	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Antimony, Total	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Selenium	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Chromium	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Beryllium, Total	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Mercury	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Cadmium	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Barium	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Endrin	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	BHC-GAMMA	—	Resolved
January 1, 2002 – December 31, 2004	Monitoring, Regular	Methoxychlor	—	Resolved
July 1, 1997 – July 31, 1997	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved
July 1, 1994 – July 31, 1994	Monitoring, Routine Major (TCR)	Coliform (TCR)	—	Resolved

Resolved addressed and confirmed by the stateArchived closed in EPA's records (typically due to age or a data correction)

Enforcement actions

February 12, 2025State Compliance achieved1 linked violation
February 4, 2025State Violation/Reminder Notice1 linked violation
July 11, 2023State Violation/Reminder Notice1 linked violation
July 10, 2023State Compliance achieved1 linked violation
February 6, 2018State Public Notification received1 linked violation
January 25, 2018State Compliance achieved1 linked violation
January 23, 2018State Public Notification requested1 linked violation
January 23, 2018State Violation/Reminder Notice1 linked violation
February 16, 2016State Compliance achieved1 linked violation
February 1, 2016State Compliance achieved1 linked violation
February 1, 2016State Violation/Reminder Notice1 linked violation
February 10, 2014State Public Notification received1 linked violation
February 4, 2014State Compliance achieved2 linked violations
January 24, 2014State Violation/Reminder Notice1 linked violation
January 24, 2014State Public Notification requested1 linked violation
January 23, 2014State Compliance achieved1 linked violation
January 15, 2014State Violation/Reminder Notice1 linked violation
January 15, 2014State Public Notification requested1 linked violation
November 14, 2012State Violation/Reminder Notice1 linked violation
January 14, 2011State Violation/Reminder Notice1 linked violation
May 15, 2009State Compliance achieved1 linked violation
May 15, 2009State Compliance achieved1 linked violation
May 15, 2009State Compliance achieved1 linked violation
May 15, 2009State Compliance achieved1 linked violation
August 5, 2008State Violation/Reminder Notice1 linked violation
August 5, 2008State Public Notification requested1 linked violation
July 31, 2008State Compliance achieved1 linked violation
December 25, 2005State Public Notification requested1 linked violation
December 25, 2005State Violation/Reminder Notice1 linked violation
June 7, 2005State Compliance achieved37 linked violations
June 6, 2005State Compliance achieved49 linked violations
April 15, 2005State Public Notification requested31 linked violations
April 15, 2005State Violation/Reminder Notice42 linked violations
April 14, 2005State Public Notification requested33 linked violations
April 14, 2005State Public Notification requested1 linked violation
April 14, 2005State Violation/Reminder Notice6 linked violations
April 14, 2005State Public Notification requested1 linked violation
April 14, 2005State Public Notification requested49 linked violations
April 14, 2005State Violation/Reminder Notice1 linked violation
April 14, 2005State Violation/Reminder Notice76 linked violations
April 14, 2005State Violation/Reminder Notice27 linked violations
August 19, 2004State Compliance achieved1 linked violation
December 23, 2002State Violation/Reminder Notice1 linked violation
August 19, 1994State Violation/Reminder Notice3 linked violations

Contact

CURTIS, CHRIS

406-666-3201

YELLOWTAIL, MT 59035