Bureau of Land Management's Decision Record and Environmental

Jersey Valley Geothermal Development Project
Environmental Assessment: NV063-EAO8-091
Small quantities of naturally occurring non-condensable gases, such as carbon dioxide (C0 2),
hydrogen sulfide (H2S), nitrogen (N2), and methane (CH 4), would be emitted to the air during
geothermal well testing. With a binary power plant, some of the binary working fluid (pentane)
would be released to the atmosphere from gaskets, rotating seals, and flanges during operations.
Also during normal operations, a small quantity of air enters the pentane loop in the air-cooled
condenser. This air leaked into the pentane loop is discharged back to the atmosphere through a
stack, along with a small quantity of pentane. During major maintenance activities on the
pentane side of the binary power plant units, the liquid pentane would first be transferred to the
pentane storage tank. However, not all of the pentane can be removed in this manner, and the
residual pentane would be discharged to the atmosphere when the binary power plant unit is
opened. All of these releases, estimated to average about 12 tons per year, are regulated through
a permit issued by BAPC to ensure that these emissions do not result in ambient concentrations
of ozone (which can be created from the reaction of ambient concentrations of hydrocarbons and
NOR) in excess of the applicable AAQS.
3.2.2.2 Alternative 1
The air quality impacts from construction, operation, maintenance and reclamation of
Alternative 1 would be identical to those described for the Proposed Action.
3.3 CULTURAL RESOURCES
3.3.1 Affected Environment
Cultural resource surveys were conducted by Kautz Environmental in 2008 and 2009. The area
surveyed (area of potential effect, APE) consisted of two large blocks, one in Lander County
totaling 4,146 acres, and one in Pershing County totaling 2,493 acres, as well as a transmission
line corridor totaling 1,282 acres (Kautz 2009).
The survey resulted in the identification and evaluation of 99 archaeological sites, seven of
which were previously recorded resources. These include 62 historic sites, 33 prehistoric sites
and 4 sites which contain both prehistoric and historic components. In addition to the
archaeological sites, 161 isolated finds were also observed and recorded.
Seven archaeological sites are recommended eligible for listing on the National Register of
Historic Places (NRHP), which include four prehistoric scatters. Fourteen prehistoric scatters
remain unevaluated. The remaining 78 sites are recommended not eligible for listing on the
NRHP (Kautz 2009).
3.3.2 Environmental Consequence
3.3.2.1 Proposed Action
All surface disturbing activities associated with the proposed project would avoid the
recommended eligible and unevaluated cultural resources. A buffer of approximately 30 to
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