INTREPID POTASH WEST PLANT DAM - NM00436-3036

Incident ID NM00436-3036
Dam Name INTREPID POTASH WEST PLANT DAM
Downstream Hazard Potential L
State NM
Incident Date 10/17/2015
Incident Type Failure
Incident Driver Seepage/internal Erosion
Incident Mechanism 1 Piping
Incident Mechanism 2 Cracking
Incident Mechanism 3 Settlement
Incident Description Piping is believed to be initiated by cracking across the reservoir floor and dam embankment caused by land subsidence due to mining activities underneath the dam and reservoir footprint. Piping tunnel was 1-2 feet diameter (not measured).
Named Hydrologic Event
EAP Enacted (Y/N) due to Incident No
Fatalities (Number) 0
Number of People Evacuated 0
Number of Habitable Structures Evacuated 0
Number of Habitable Structures Flooded 0
Other Infrastructure Impacts None
Economic Damages (in $)
Volume released at failure (ac-ft) 1.5 ac-ft
Response
Additional Remarks or Updates Brine release from the downstream toe of the dam was noticed by a worker around 7:15AM who notified his superior. Equipments and workers were mobilized in an attempt to stop the leak, but were unable to stop it and leak continued until the entire content escaped (reservoir was empty by 4:00PM the same day). An intermediate dike containing the reservoir on the south side was breached to divert the reservoir content into different area. This helped in reducing the brine release quantity to the downstream area. Escaped quantity was estimated around 500,000 gallons. Piping tunnel was 1-2 feet diameter (not measured).
Incident Time 7:15 AM
Incident Duration 1 day
Incident Report Produced Yes
Information Sources Dam owner and NM Dam Safety Bureau
Owner Type P
Dam Type RE
Primary Purpose(s) T
EAP NR
Year Completed 1978
Year Modified 0
Dam Height 68 ft
Max Storage (ac-ft) 2078 ac-ft
Surface Area (acres) 128 acres
River Name PECOS RIVER-TR
Latitude 32.4836
Longitude -103.927
Regulatory Agency(ies) Office of the State Engineer
NID Number NM00436
Attachments Y