DOI-BLM-NV-C010-2011-0527-CX

NEPA Document Collection for: DOI-BLM-NV-C010-2011-0527-CX
CX at Dixie Valley Geothermal Area for Geothermal/Exploration

CX for Passive Seismic Survey at Dixie Valley Geothermal Area for Geothermal/Exploration

Proposed Action

This is a revision to AltaRock Inc.'s previously approved seismic survey reflecting revised locations. The new proposal also differs in the manner of installation. Original site locations and installation were analyzed under DOI-BLM-NV-COI0-2011-0008-CX. The new proposal is to conduct a passive seismic survey which will consist of 27 broadband seismometers installed over a broad area centered on Dixie Valley. Only 19 of these sites are located within the Stillwater Field Office, CCDO. The remaining 8 sites are located within the Winnemucca Field Office. The passive seismic survey is expected to last three months. Sites have been moved from the original proposal to be closer or adjacent to existing roads to mitigate overland travel. Ground disturbance would be limited to holes for placement of the seismometers. For each site a hole no more than 36 inches in diameter and 42 inches deep will be dug by hand or small Bobcat excavator with a bucket no larger than 12 inches wide, the smallest available. A container used to house the seismometer will be placed in the hole and cemented in place. The container will be covered with a removable tile and the entire unit backfilled to the surface. A cable will extend from the seismometer to the surface where it will be connected to a weatherproof box containing electronics, data logger, and battery. Solar panels used to recharge the battery would be mounted on top of the weatherproof box. The entire assembly would be mounted on two parallel horizontal pipes measuring approximately 7 feet long and 3 inches in diameter. Access would be through existing roads or short stretches of overland travel. Following removal of the seismometers the remaining vaults would be buried in place beneath at least 12 inches of soil.

Data Completion Notes

No document available to further populate.