CBM Production and the Environment
Land
Ember’s Horseshoe Canyon coalbed methane production projects leave a smaller footprint on the land than many other types of natural gas projects. The Horseshoe Canyon is found at a shallow depth, which means smaller rigs are required, and a smaller operational lease is needed.
During CBM drilling, the lease measures about 360 feet x 360 feet. The lease is then reduced down to some 50 feet x 50 feet when a well is placed on CBM production. Horseshoe Canyon wells require minimal permanent equipment at the surface, typically just compression to move the coalbed methane into pipelines. At most wells, this equipment takes up an area roughly 10 feet x 10 feet, leaving little disturbance on the land.
Alberta’s regulations
With CBM production, only four wells are drilled per section under current regulations. Some areas may ultimately require up to eight or more wells per section for optimal drainage of the coalbed methane gas in the coals. Working to keep a small operational footprint, the industry is continuing to experiment with different techniques such as directional and horizontal drilling of wells to further reduce the imprint on the land.
Water
Some coal trends produce large amounts of water during the initial CBM production phase. The Horseshoe Canyon coals do not produce water; these coals are considered “dry,” meaning they store little water and do not produce water during the extraction phase.
The Horseshoe Canyon is found at shallow depths of 150 – 700 metres (500 – 2,300 feet). During drilling, the wellbore is completed with two casing strings that are both cemented in place to isolate groundwater aquifers from the productive CBM intervals. Ember adheres to strict water protection measures put in place by regulatory authorities and employs standard operating practices that go beyond these policies.
Water well guidelines
Prior to licensing a CBM drilling well, the operator is required to test all water wells within a 600-metre radius. If no water wells are present, the radius increases up to 800 metres. This must be documented in accordance with Alberta Environment standards. These tests provide a baseline for existing water wells and to confirm there are no adverse effects from CBM production.
For more information, contact Ember Resources.