The power plant proposed for the Wikieup area will have no major impact on water and other natural resources, but could harm plants and animals along the Big Sandy River watershed, according to a draft environmental statement.
The DEIS, issued Friday by the federal Bureau of Land Management and Western Area Power Administration, examines the short- and long-term effects on future water supplies in the Wikieup area and the effects on fish and wildlife, the community, air and water quality and other aspects.
"The reason there isn't as many significant effects as you expect from a project like this is that Caithness has … proposed measures to reduce those effects or eliminate those effects," said Dwight Carey, a consultant who is serving as project manager for the BLM.
Measures include groundwater monitoring, dust control and recharging the Big Sandy River from other water sources.
Carey and other consultants prepared the DEIS in response to a request by Caithness Big Sandy LLC to build a 720-megawatt, natural gas-fired plant in the Wikieup area.
The BLM requires an environmental study because a natural gas pipeline supplying the proposed power plant needs to pass through federal lands administered by the agency.
WAPA has a say because its grid would carry electricity generated by the Big Sandy Energy Project.
The proposed power plant cleared both the Mohave County Planning Commission and county supervisors in 2000, but awaits approval from state and federal agencies, including the BLM and the Arizona Power Plant and Transmission Line Siting Committee.
The proposed plant sparked opposition from some county residents who fear the plant would deplete the water supply.
It is expected to use 3,200 acre-feet of water a year.
Groundwater monitoring conducted for the DEIS predicted that without an increase in flows water levels in the shallow aquifer could drop by less than one foot, according to the executive summary.
Carey said the upper aquifer is no more than 100 feet deep.
The DEIS recommends mitigation measures such as requiring Caithness to compensate landowners affected by reduced flows in Cofer Hot Spring.
Caithness hired Paradise Valley geologist Paul Manera to drill wells to determine the depth of the aquifers and the extent of the water supply.
Staffers from the consulting firm of URS reviewed Manera's data, Carey said.
The power plant could harm the endangered Southwestern willow flycatcher and other sensitive plants and animals by damaging their habitat, according to the DEIS.
The DEIS consists of two thick documents.
However, power plant opponent Jack Ehrhardt of Citizens for Future Generations thinks it may not be thorough enough.
Ehrhardt said it does not examine the water savings that would be achieved if Caithness were to switch from a system that uses water to cool its turbines to an air-cooled plant.
"This book is supposed to represent environmental compatibility," Ehrhardt said.
"From what I have seen, they are going to make the same withdrawals of water that they had said in their original comment.
I don't see any improvement in the original systems."
Caithness officials could not be reached for comment on the DEIS.
The DEIS will be the subject of a public workshop that the BLM and WAPA have scheduled for 6 p.m.
to 9 p.m.
July 10 in the Wikieup Bible Church off Chicken Springs Ranch Road.
A public hearing on the DEIS is set for the same time and location July 24.
The final DEIS, which will incorporate public comments, is scheduled to be released in October, according to a newsletter from the two federal agencies.
They are scheduled to make a decision a month later.