Environmental Implications - Surface Operations
Impact Report: Surface Operations
Of all the aspects of surface operations (pad construction, camp construction, personnel, dining, lodging, maintenance shops, water plants, waste water plants) the largest impact will be caused by the physical existence of the drilling pad. However, all activity has impact, just varying in terms of duration and geographic scope. The impacts of this are listed below, along with a rating of significance. The rating of significance is based on the intensity (magnitude, geographic scope, and frequency/duration) and the probability of occurrence, with the scale being high, moderate, or low. Probability of biological impacts is extremely difficult to predict. Thus, the probability should be evaluated in the context of professional judgment and past occurrences of impacts. In ANWR this is complicated because there has been no prior development to reference to.
- Support: Steel poles
o Direct impact on permafrost.
o Attraction for curious, nesting, or hiding animals.
- Operating Surface: Aluminum sheets
o Damage to tundra vegetation by oil leaks
o Damage to tundra vegetation by shading
- Transportation of the pieces: Helicopter
o Flight will create noise that may be detectable to animals on the ground surface, and occasionally wintering birds
o No landing pad will be needed as the pieces are to be lowered into place.
REQUIREMENTS OF PERSONNEL
- Sewage Disposal
o Transport of solids will have noise effects and need for further development of helicopter/plane landing and pumping facilities
o Disposal in or on the tundra will impact the chemical composition of the tundra, and could be especially harmful if water sources are affected.
o Fresh water for human use is scarce on the North Slope. Any large needs would deplete fresh water sources for animals, thus possibly beginning a chain of impact through the ecosystem
o Wetland ecosystems would be disturbed by the collection or piping of water from them
o Transportation of food would cause impacts. See below.
o Storage of food might attract animals.
o Disposal of trash. Might attract animals. Must be flown out eventually (See below).
Note: Possibility in all this for introduction of an invasive species of plant or animal.
o Noise effects from air travel
o Tundra and animals impacted from landing pad/equipment
1. Non-seismic exploration
Due to the fact that magnetic and gravitation exploration do not give off magnetic waves, the only effects produced by this method are caused by the service operations associated with the method.
The effects are:
Due to the airplanes used, there will be noise pollution. In addition to that, the nitrous oxides and carbon monoxide produced will reduce the air quality. Mild, wide-spread, short-term.
Any surface operations necessary will be conducted by attaching the magnetic exploration equipment to seismic exploration trucks thus requiring no extra vehicles of transport.
2. Seismic Exploration
A very useful tool that we relied on when conducting our evaluation is the Seismic exploration that was conducted along the coastal plain of the Arctic Refuge during the winters of 1984 and 1985.
Also note that 3-Dimensional subsurface image creation requires a much denser grid than that required for 2-D. The 1984-85 trails were usually four miles apart, whereas the 3-D seismic trails that are currently impacting areas where they are in use are about half a mile (or less) apart. This means that the tracked vehicles will basically blanket the area. 3-D crews are twice the size of 2-D crews, so more than twice the tracked vehicles are out on the tundra (more equipment and more bulldozers to transport the camps). Furthermore, the turns that the heavy equipment need to make are much tighter in 3-D seismic than they are in 2-D seismic, so the damage made to vegetation and the tundra in general is greater.
Strong winds usually blow the snow into depressions, leaving the higher areas with thinner snow cover and making them much more susceptible to impacts from vehicle tracks. After the 1984-85 seismic exploration 1400 miles of trails that have been made by drill, vibrator and recording vehicles impacted the tundra. In addition to the trails left by the exploration equipment, trails were also created by D-7 Caterpillar tractors that pulled ski-mounted trailer-trains between work camps. In 1999, 15 years after the exploration conducted a significant amount of the trails persisted. Some of them became troughs that are visible from the air (all vegetation removed). In other trails, the amount and type of vegetation present changed. This implies that the entire food-web dependant on this vegetation is affected and altered. Animals can be displaced out of their original habitats if their source of food is no longer available. In other areas, permafrost melted and the trails remained wetter than they previously were. Severe, localized, long-term.
Even though the caribou and birds are usually absent from the 1002 Area during the winter months, there are several species that are adapted to the harsh conditions and that remain in the area during the winter. These species are likely to be affected by the seismic exploration activities. They include primarily muskoxen and polar bears, but there are also other species including wolverine, arctic fox and arctic grayling. In addition, the sensitive arctic tundra vegetation is affected. Moderate, localized, short-term.
At times air travel will not be possible due to extreme weather conditions
which can persist for days. As a result, local storage needs would increase
and more pad area would be required. (see environmental impact of surface
operations). Mild, localized, short-term.
c. C-130 Hercules
Landing on snow cover may put pressure on the surface. Moderate, localized,
Permafrost destroyed when drill bits driven into the ground. The area around the drill hole thaws. Severe, localized, long-term.
The flooding technique of recovering oil from the wells will have two
Benefits of drilling plan:
- Directional drilling and coiled tubing are the best choice: they will
provide a minimal impact on the environment. Directional drilling allows
for the installation of infrastructure beneath these areas without affecting
the delicate ecosystem; animal habitats and sensitive areas can be avoided
as a result.
Permafrost thaws around pole-support structure. Mild, localized, short-term.