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Water Facts
Information in this section was found at: Coalbed Methane--An Untapped Energy Resource and an Environmental Concern , and Colorado Geological Survey – "Rock Talk," July 2000, COGCC Water Quality Report 2000.
As with any gas or oil well, regulations have been established and are enforced to protect surface water, vegetation, wildlife, and subsurface groundwater. Coal bed methane reservoirs have the added distinction of producing large quantities of water. In order for gas to be released from the coal, its partial pressure must be reduced, and this is accomplished by removing water from the coalbed. Some coals contain potable water that can be used for irrigation and livestock. Other coals produce more saline, and thus non-potable waters that must be disposed of properly. Water may be discharged on the surface if it is relatively fresh, but often it is injected into rock at a depth where the quality of the injected water is less than that of the host rock. This water then becomes a resource for some future use. Regardless of the quality of the produced water, it is not mixed with the shallow aquifers that serve as a source of drinking water.
More than 90 percent of the water coproduced with oil land gas is disposed or used for enhanced recovery by underground injection. Most of the rest is disposed in evaporation and percolation pits. A small amount is discharged under Colorado Department of Public Safety permit as a waste and an even smaller amount is put to beneficial uses such as dust suppression on lease roads and emergency fire fighting. One landowner in La Plata County filed for and obtained the right from Water Court to use produced water for irrigation.
The water produced from coalbed methane wells, in general, has fairly low total dissolved solids and no liquid hydrocarbons. Many landowners have expressed an interest in using this water. The Office of the State Engineer -- Division of water Resources, the COGCC, and the Water Quality Control Division currently are reviewing our respective rules and regulatory obligations pertaining to this water.
The COGCC is an implementing agency for water quality standards and classifications adopted by the Water Quality Control Commission for ground water protection. This authority was provided by SB89-181, and is restated and clarified by a Memorandum of Agreement between the agencies.
The COGCC permits non-commercial Centralized E&P Waste Management Facilities. Generally these are larger than a typical tank battery that might handle produced water from one to a few wells. The COGCC also permits commercial Underground Injection Well facilities.
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