BLM projects ‘insignificant’ impact from seismic work in ANWR

A 3-D seismic survey may be the first sign of controversial oil development in Arctic National Wildlife Refuge

According to a proposal, geophysical services company SAExploration is proposing to do seismic work in ANWR.

Seismic work used to involve dynamite. Now it’s mostly done with vibrating trucks that send shock waves into the ground. Lines of sensors on the surface record the waves that bounce back to map underground formations.

The company wants to bring about a dozen vibrating vehicles to the refuge, each mounted on a rubber track.

Bureau of Land Management officials said this week they see no need to do a full environmental impact statement for the seismic work and expect to approve the request in time for work to begin this winter.

Several vibrating vehicles would drive parallel lines across the frozen tundra, stopping frequently to lower their vibration plate for about 20 seconds and then move to the next spot.

The trucks would drive about eight lines across a typical square mile, according to the company’s application.

The plan is to shoot seismic across the 2,600 square-mile coastal plain.

BLM spokeswoman Lesli Ellis-Wouters said it’s the same technology that was used in the National Petroleum Reserve-Alaska, west of the refuge.

“We felt that there would be insignificant impact, so we’re planning on doing an environmental assessment and when that is available we’ll post that environmental assessment, with a draft finding of no significant impact,” Ellis-Wouters said.

An environmental assessment is kind of the junior cousin of a full “environmental impact statement.” It’s less rigorous and less detailed.

the BLM could order a more thorough examination if it learns something unexpected in the assessment, or in the public comment period that follows, Ellis-Wouters said.

“At the end of the 30-day public comment period if we don’t receive substantial input to change our finding of no significant impact, we would issue a decision record, and then the activity could be authorized,” Ellis-Wouters said.

In addition to the vibration trucks, the work will require two mobile camps, each able to house 160 people, and a variety of support vehicles.

Defenders of Wildlife attorney Jason Rylander said the activity is far from harmless.

“Seismic has tremendous potential for serious environmental impacts, Rylander said. “In fact, you can still see the scarring from the last time that seismic was allowed, in only just a small portion of the refuge.”

In the 1980s, Congress allowed a 2-D seismic survey on the coastal plain of the refuge, resulting in more than a thousand miles of trails.

The U.S. Fish and Wildlife Service said most of the trails recovered well in the first decade but a few miles were still visible from the air decades later.

Data collection for a 3-D seismic survey is more intensive with far more sensors.

Rylander and other environmentalists especially are worried about the impact seismic work could have on polar bears.

“During denning season, it can cause mother polar bears to leave their den,” Rylander said. “It can expose polar bear cubs to disturbance. We’re very very concerned.”

U.S. Fish and Wildlife Service said noise disturbance and passing vehicles have prompted some mother polar bears to abandon their dens while others seem to adjust to industrial noise.

The Interior Department hopes to offer leases for drilling in ANWR next year.

While it’s responding to the application to conduct seismic work, BLM also is preparing a separate environmental impact statement for the lease sale itself.

Congress mandated the lease sale last year, but Rylander said environmental groups aren’t giving up.

“Whether the Trump administration ultimately issues a lease or not, our aim is to ensure that this land is never drilled,” Rylander said.

BLM expects to hold another public comment period and at least seven public meetings on the lease sale proposal this fall or winter.

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