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Vol. 1: Executive Summary
Introduction
EnCana Corporation (EnCana) proposes to carry out a shallow gas infill development Project (the Project) within the boundaries of its existing developed shallow gas field in the Canadian Forces Base (CFB) Suffield National Wildlife Area (NWA) in southeast Alberta. The NWA lies along the eastern edge of CFB Suffield, approximately 50 km northwest of Medicine Hat and 250 km southeast of Calgary.
Alberta Energy Company (AEC), EnCana's predecessor, was founded by virtue of agreements with the provincial and federal governments. EnCana's foundation at CFB Suffield has enabled it to become the leading operator in native prairie environments. By January 2007, EnCana had drilled over 3500 wells in the Western Canadian Shallow Gas Complex to 16 wps density. The techniques used to drill, complete and tie-in the wells for the Project are essentially the same techniques EnCana has successfully used and improved for other development activities on the native prairie. Given the increased environmental sensitivity within the NWA, EnCana intends to supplement the following aspects of its program for the Project:
EnCana Corporation (EnCana) proposes to carry out a shallow gas infill development Project (the Project) within the boundaries of its existing developed shallow gas field in the Canadian Forces Base (CFB) Suffield National Wildlife Area (NWA) in southeast Alberta. The NWA lies along the eastern edge of CFB Suffield, approximately 50 km northwest of Medicine Hat and 250 km southeast of Calgary.
The Project, a continuation of EnCana's existing shallow gas infill well development throughout the NWA, covers an area of approximately 458 km2. EnCana's expertise in shallow gas infill drilling will be reflected in all phases of the proposed Project.
The Project is subject to environmental assessment pursuant to the Canadian Environmental Assessment Act (CEAA). This environmental impact statement (EIS) has been prepared by EnCana to meet the CEAA and Alberta Energy and Utilities Board (EUB) requirements.
Project Description
EnCana proposes to drill 1275 infill wells over three drilling seasons (beginning in fall 2008) to extract remaining shallow tight sweet gas from the NWA. It is expected that a maximum of 16 wells per section (wps) will be drilled. Wells will be tied in to existing and new pipeline infrastructure by 50.8 mm (2 in.) high-density polyethylene plastic (HDPE) pipe, which will normally be ploughed in to minimize surface disturbance. Approximately 40 km of new 101.6 mm, 152.4 mm, and 203.2 mm (4, 6, and 8-in.) steel pipe will be required to effectively transport the additional gas volumes to compressor stations outside the NWA. While working areas during construction will typically be 15 m wide, the width of the linear disturbance (i.e., topsoil stripping for ditching installation of steel pipe) will be limited to 2 to 4 m.
- licensed surface water sources (South Saskatchewan River) within the NWA
- wells or spring-fed dugouts near the NWA
- transporting water from the Municipality of Medicine Hat
Construction activities have been scheduled to take place to avoid military lock-out and sensitive wildlife periods (such as snake migration, and migratory birds and burrowing owl breeding periods). As such, construction will take place during the October to April period.
The Project will be accomplished over four phases:- preconstruction which will include baseline mapping, site selection, and an ordinance sweep
- construction which will include drilling, completion, tie-in of the wells, and post-construction cleanup
- operations which will include well testing, well and pipeline inspection, swabbing (if necessary), refracturing (if necessary), and post-construction reclamation maintenance (if necessary). Production is anticipated to continue for approximately 20 to 40 years.
- decommissioning and abandonment which will be carried out on both production and pipeline facilities to the regulatory standards in place at the time
Alberta Energy Company (AEC), EnCana's predecessor, was founded by virtue of agreements with the provincial and federal governments. EnCana's foundation at CFB Suffield has enabled it to become the leading operator in native prairie environments. By January 2007, EnCana had drilled over 3500 wells in the Western Canadian Shallow Gas Complex to 16 wps density. The techniques used to drill, complete and tie-in the wells for the Project are essentially the same techniques EnCana has successfully used and improved for other development activities on the native prairie. Given the increased environmental sensitivity within the NWA, EnCana intends to supplement the following aspects of its program for the Project:
- timing of the activities " development of a detailed environmental protection plan
- innovative reclamation practices
- well sites located to reduce environmental effects
- reduced footprint of wells and pipelines
- Project-specific training
- enhanced monitoring and follow-up activities
Regulatory Setting
Natural gas development in the NWA is regulated by several agencies, and various pieces of legislation govern EnCana's operations. Surface rights in the NWA are owned by the Government of Canada, while the Province of Alberta owns the subsurface rights. To develop this Project in the NWA, EnCana requires a permit pursuant to section 4 of the Wildlife Area Regulations. The Department of National Defence (DND) is responsible for issuing that permit as administrative control has been delegated for the CFB Suffield NWA to the DND. This federal authorization is included in the Law List Regulations pursuant to the CEAA, and, therefore, an EIS pursuant to the CEAA is required. EnCana also requires approvals from the EUB. A Joint Panel will review the Project.
Draft guidelines for the Project were issued by the CEA Agency on August 25, 2006. Following a period of public review (which included comments from government agencies, interested individuals or parties and EnCana); the Joint Review Panel released the Final Guidelines for the EIS on December 20, 2006. The content and structure of the EIS has been specifically developed in accordance with these Final Guidelines.
The following federal departments have self-identified as Federal Authorities (FAs) and will provide specialist advice to the assessment conducted by the Panel:- Agriculture and Agri-Foods Canada
- Environment Canada
- Fisheries and Oceans Canada
- Health Canada
- Natural Resources Canada
- Parks Canada
Environmental Setting
The NWA encompasses 458 km2 of prairie grassland including sand hills, glacial coulees, riverbank and breaks along the South Saskatchewan River valley. From an ecological perspective, the area is found within the Dry Mixedgrass Subregion of the Grasslands Natural Region of Alberta.
The Project area is characterized by a semi-arid continental climate with warm summers and cold winters. The terrain is hummocky to rolling, for the most part, with the southern one-fifth of the area being relatively level to undulating. Surface relief is typically 10 m except in the southern portion where relief in the South Saskatchewan River valley is as much as 150 m. Surficial deposits are till, with some areas of water-sorted materials and aeolian deposition. Soils are predominantly chernozemic.
Vegetation is characteristic of the short grass prairie region, where the main grasses are blue gramma grass and common speargrass. Sage is the dominant shrub species, particularly in areas of overgrazing. Trees occur only in the river valleys and in irrigated areas.
A majority of the Project area is within wildlife key areas for antelope and white-tailed deer while the north of the Project area is a key ungulate area for mule deer (Alberta Fish and Wildlife 1985). The Project area is also within migratory bird habitat subregions as defined by Poston et al. (1990) for burrowing owl and ferruginous hawk.
The South Saskatchewan River defines the east boundary of the NWA and is the most prominent surface water feature in the Project area. There are approximately 27 mapped drainages, which consist of steep gullies that are incised into the west valley wall of the South Saskatchewan River, and an additional 17 drainages that end at terminal closed depressions with no surface outlet. From a local drainage perspective, the NWA is in the driest part of Alberta, and the interior drainages are normally dry except for a brief (typically two-week) period of snowmelt, usually in March lasting for one or two weeks.
Use of the Suffield Block lands for military research began in 1941 and the creation in 1971 of CFB Suffield (one of the largest army training bases in the Western world). In 1975, EnCana began resource development at CFB Suffield as the area was recognized as comprising a measurable source of sweet natural gas. Oil and gas development, military activities and cattle grazing have been conducted concurrently in this area for more than 30 years.
Scope of the Environmental Impact Statement
The EIS comprises an assessment of the Project components and phases through a combination of office and field studies. Environmental baseline conditions were defined through a review of a considerable amount of baseline information, including a large amount of data from EnCana's long-term operations in the area including sections of up to 16 wps. This aspect of the EIS analysis is unique and informative of the potential effects of the Project. This data and information was supplemented by environmental field programs to verify the literature. Depending on the discipline, techniques including field studies, field observations, literature review and/or modelling were used for analysis. Field studies were carried out for key disciplines including soil landscapes, vegetation, wetlands, wildlife, aquatics, historical resources, paleontological resources and noise.
A standard methodology following CEAA guidelines was used by all disciplines to assess the effects of the Project on the environmental components. Issues were identified for each discipline to focus the EIS on Project-related disturbances that could affect the environment. Mitigation measures were developed to eliminate or minimize environmental and social effects. Residual environmental effects were classified as being insignificant, negligible or significant.
Environmental Impact Statement Results
The findings of the assessment for each environmental component are summarized below.The environmental effects of the Project are anticipated to be insignificant.
Vegetation - Environmental effects of the Project on native prairie grassland integrity are considered to be insignificant because of constraint avoidance through pre-planning, on-site planning, a small Project footprint, no additional road construction and minimal disturbance practices. Project effects of construction, operations and decommissioning on rare plants and plant communities are predicted to be insignificant as a result of reduced effects through constraints mapping and relatively low magnitude of disturbance to uncommon vegetation cover types.
Wetlands - The residual environmental effects of the Project on wetland supply and wetland function are all predicted to be negligible for all Project phases. Wetlands will be avoided to the extent practically possible and mitigation measures will be put in place to limit potential disturbance where avoidance is not possible.
Wildlife - Residual environmental effects on wildlife are assessed as negligible or insignificant for the construction, operations and decommissioning phases of the Project since minimal disturbance practices will be utilized and Project construction activities will be restricted for critical wildlife periods.
Biodiversity - The effects of the Project on species-level biodiversity, habitat diversity, and landscape biodiversity are assessed as negligible for all phases due to the small size of the Project footprint and the mitigation measures.
Groundwater - Effects of the project on groundwater quantity and quality are assessed as negligible and localized for all phases because the magnitude of water withdrawal required for the Project is small. In addition, a variety of groundwater and surface water sources will be used to minimize effects on any single source.
Surface water - The environmental effects from the Project on surface water are rated as negligible for all phases due to the small amounts of water withdrawals required for the Project and planned mitigation measures designed to minimize potential water quality effects.
Aquatic Ecology - Project environmental effects on aquatic ecology components were determined to be negligible for all project phases because the duration of water withdrawals will be short and the amount of water required is limited.
Soil - Project environmental effects on soil were determined to be insignificant for all phases. Monitoring of selected soil landscapes, particularly those prone to soil salinization, water erosion and wind erosion will be conducted to ensure that mitigation measures are effective and that environmental effects on soils remain insignificant.
Historical resources - The residual environmental effects of the Project on known and undiscovered historical resources during all Project phases are predicted to be insignificant since construction sites will be pre-selected and sites will be relocated or other appropriate mitigation will be employed if resources are discovered. If historical resources are discovered during construction, work will cease and appropriate regulators will be contacted and their instructions followed.
Palaeontology - Potential effects on palaeontological resources were determined to be negligible because well sites and pipeline routes will be selected to avoid palaeontological resources and mitigation measures will be implemented during the construction phase of the Project. No environmental effects are predicted during the operations, decommissioning and abandonment phases.
Socio-economics - All Project effects were rated as insignificant, with the exception of public and community services infrastructure (transportation) and regional population, which were rated as negligible.
Air quality - The environmental effect of Project construction activities on air quality was assessed as insignificant given the local nature, short duration and reversibility of the effects. Effects of Project operations and decommissioning and abandonment activities on air quality were assessed as insignificant.
Noise - Residual environmental effects of the Project on noise levels were rated as insignificant because the cumulative predicted noise levels from the Project and because individual Project activities are below the EUB regulatory targets.
Human health - The residual human health environmental effects associated with the Project chemicals of potential concern (COPCs) were assessed as insignificant due to the high degree of conservatism incorporated into the prediction of the maximum air concentrations. The predicted health risks associated with acrolein, nitrogen dioxide (NO2), and particulate matter less than 2.5 microns in diameter (PM2.5) are not expected to translate into health effects in people. Very few people frequent the area.
Mitigation Measures
Mitigation strategies are proposed to avoid or minimize the environmental effects of the Project including: constraint avoidance through pre-planning, on-site selection, avoidance of sensitive locations and timing periods, development of mitigation measures to address site specific and general issues, and monitoring during construction and operation phases.
The draft Project specific Environmental Protection Plan (EPP) encompasses environmental protection measures that will avoid or minimize the potential environmental effects associated with the construction of the Project. The comprehensive EPP, to be developed and finalized, will enable EnCana to facilitate and manage the successful implementation of mitigation measures.
Cumulative Effects Assessment
The application of mitigation measures coupled with avoidance of sensitive environments, results in potential environmental effects being rated as negligible for the following disciplines: wetlands, biodiversity, groundwater, surface water, aquatic ecology, and palaeontology. For this reason, cumulative effects assessments were not undertaken.
Potential environmental effects were determined to be either insignificant or negligible for socio-economics, air quality, noise and human health disciplines and no other projects or activities will interact with the Project environmental effects that were not considered in the project environmental assessment; therefore, no cumulative effects assessment was conducted.
A cumulative effects assessment was conducted for historical resources, vegetation, soils and soil landscapes, and wildlife and wildlife habitat disciplines. The cumulative effects for these disciplines were determined to be insignificant.
Environmental professionals will be on-site when specific well locations are being selected to avoid all environmentally and historically important locations. This will also help minimize cumulative effects of the Project. Details of cumulative effects for each biophysical resource are discussed in detail in Volume 3 of the EIS.
Malfunctions and Accidental Events
EnCana has considered the various potential malfunctions and accidental events that may occur during the Project and may result in potential environmental effects. These include collisions and releases from vehicles, pipeline accidental releases, blowouts and surface casing vent flow, and grassland fires. Design, inspection, maintenance, and integrity assurance programs, as well as proven engineering techniques, will be in place to prevent such events from occurring. All safety procedures will be documented and in place before the commencement of routine operations.
All fuel, chemicals, and wastes will be handled in a manner that minimizes or eliminates routine spillage and accidents. EnCana's EPP and Emergency Response Plan (ERP) include safe chemical handling and storage procedures, as well as accidental release response measures, such as the use of cleanup equipment, training of personnel, and identification of personnel to direct cleanup efforts, lines of communications, and organizations that could assist cleanup operations.
Conclusion
EnCana has held mineral and access rights in the Suffield area since 1975, for which significant consideration was paid. EnCana (and its legacy company, AEC), has worked throughout its history of operating in the area to ensure the environment is protected. Environmental protection has evolved and improved as EnCana continuously improves its practices. It is of note that EnCana provided input to the Canadian Wildlife Service and to CFB Suffield in the creation of the NWA at Suffield, and supported the creation thereof on the understanding that shallow gas operations would be allowed to continue, having regard to EnCana's commitment to environmental protection in the NWA. During the development of 1145 wells in the NWA since 1975, EnCana has continuously updated and improved its practices to minimize environmental effects on the native prairie. For this Project, and given the unique nature of the NWA, EnCana has enhanced its best practices to maximize environmental protection, notwithstanding that its exisitng best practices provide sufficient protection in other areas of the Province and at CFB Suffield. In developing this Project, EnCana has taken an expansive approach to considering potential effects to ensure the cumulative effects of the Project are known, understood and mitigated.
EnCana's commitment to environmental protection is evident in the conclusions in the EIS: as indicated and supported by the analysis and conclusions in the EIS, the environmental effects of the Project are anticipated to be insignificant.