Background:
Energy development in eastern Montana, including coal mining, coalbed natural gas (CBNG), and convential oil and gas drilling (O&G), on federal lands involves groundwater monitoring to assist decision makers in managing the leasing program and preparing NEPA documents.
Since
1972 the BLM has assisted and provided funding to collect water levels and water quality data from a network of monitoring wells, predominatly on public lands, to assess impacts from energy development.
Objectives:
To provide scientifically sound, long-term data & corresponding reports; descriptions of the ground-water systems in coalbed natural gas (CBNG) prospective and producing areas, surface coal mining areas, and O&G producing areas of Montana, and models of future conditions in these areas.
This includes fulfilling the groundwater monitoring requirements identified in the Final Supplement to the Montana Statewide Oil and Gas Environmental Impact Statement and Proposed Amendment of the Powder River and Billings Resource Management Plans (FSEIS).
Specific data that are required are identified in the FSEIS Monitoring Appendix , but also include variables such as water levels, aquifer physical characteristics, and quality of the ground water.
Descriptions of ground water systems are based on interpretations of these data:
these descriptions include base line conditions, CBNG changes, coal mining changes, O&G changes, human-induced non-changes, recovery, and ambient seasonal patterns.
Models will be refined to improve predictive abilities and designed in a way that permits intuitive 3rd party manipulatin for predictive modelling of pumping scenarios associated with future projects.
Public Benefit:
The monitoring data allows developers, regulators, land-management agencies, and the general public to determine the effects of coal, coalbed natural gas, and O&G production on the groundwater resource and existing water rights.
The data will provide critical, third-party information on baseline conditions and changes that occur during and after development.
In addition, the information will facilitate decisions regarding bond release, permitting of leases, development of resource, and techniques for development.
All data will be incorporated into the publically available GWIC database.
Groundwater flow models and/or gridded estimates of physical basin characteristics, commonly used as inputs to groundwater flow models, will be developed to facilitate public use of the in situ data.