Medicine Lake Highlands

Fourmile Hill Geothermal Development Project-Engineering Analysis for the Authority to Construct and Permit to Operate

Client: Carol MacGregor
Geologica Geothermal Group personnel provided environmental and geothermal expertise to support the Siskiyou County Air Pollution Control District’s (SCAPCD) decision-making process as the CEQA lead agency for the Fourmile Hill Geothermal Development Project in the Medicine Lake Highlands. The full-scale development project included drilling, well testing, surface production equipment, generation facilities and transmission lines. As the lead agency, the SCAPCD, was responsible for approving the EIR and granting permits for drilling permits, flow testing, wellfield development, power plant construction and brine reinjection. Geologica Geothermal Group addressed the primary environmental issues of potential production impacts to Medicine Lake, Fall River Springs and the regional groundwater system; and potential air quality, biological resource, and surface water impacts that could result from geothermal surface spills. Engineering analysis was completed for initial well permits, wellfield development and power plant construction. Additional work supported CEQA approval, and technical support for public notices, public meetings and staff presentations to the SCAPCD Board. Regulatory concerns included Ambient Air Quality and New Source Performance Standards (AAQS, NSPS), Prevention of Significant Deterioration (PSD), New Source Review (NSR) and Best Available Control Technology (BACT), Title V, California AB2588 and Health Risk Assessment, Title 8 Worker Health & Safety, and CEQA.