Case Studies

Fiale Caldera Geothermal Area, Djibouti Geothermal Exploration Project Exploration Drilling program and Testing, Resource Definition and Environmental Management Client:Electricite de Djibouti

Geologica Geothermal Group is currently providing lead technical consulting services and project management for the geothermal drilling program and testing for exploration, resource definition and environmental management for large-scale geothermal power generation in the Fiale Caldera Area of the Lake Assal Region. Geologica Geothermal Group’s technical role has included planning, management, procurement, and on-site technical oversight for well targeting, drilling and testing of potential geothermal resources, followed by a resource and geothermal power development feasibility study and IPP tender support, and geochemical assessment and mitigation. Project management tasks include contracting for drilling and testing services, contract management and invoice tracking, budgeting and cost tracking for multiple funding sources.

Sorik Marapi Geothermal Project, Indonesia Technical Services for Geothermal Resource Management, Development at Sorik Marapi Client: Sorik Marapi Geothermal Power-KS ORKA

Geologica Geothermal Group provides ongoing independent technical and project planning support for a multi-stage geothermal power project in Sorik Marapi, in North Sumatra, Indonesia. Technical contributions include reservoir assessment and development planning for up to 240 MW of geothermal development including well targeting, conceptual and numerical reservoir modeling, fluid geochemistry evaluation, well test planning, well test implementation and analysis, reservoir monitoring and management, and reservoir modeling. Geologica Geothermal Group also provides on-site support including drilling engineering, on-site drilling supervision, and well site geology. Geologica Geothermal Group is currently incorporating well prognosis, well test planning, implementation and analysis, interpretation of results into well targeting and engineering for drilling of additional production and injection wells. Additional work includes exploration and geothermal resource potential assessment of the undrilled portion of the license.

Sokoria Geothermal Project, Indonesia Technical Services for Geothermal Resource Management, Development at Sokoria Client: PT Sokoria Geothermal Indonesia -KS ORKA

Geologica Geothermal Group has developed a conceptual model for reservoir assessment and well targeting for up to 30 MW of geothermal power generation based on the review of exploration geo-surveys, additional geologic and structural mapping, geochemical assessment, and early drilling review. Geologica Geothermal Group’s ongoing support includes well test analysis, well capacity estimates for pumped and/or artesian wells, silica scaling and acid fluid mitigation plans. Additional support includes drilling engineering, on-site drilling supervision, and well site geology, well prognosis, well test planning, implementation and analysis, interpretation of results and incorporation into well target and engineering of next drilling will be used for additional well drilling program at Sokoria Geothermal Project.

Olkaria, Kenya Environmental and Resource Assessment Client: World Bank, International Finance Corporation

Geologica Geothermal Group, provided environmental and geothermal resource assessment to support financing considerations by the International Finance Corporation (IFC) for a proposed expansion of the Olkaria Geothermal Field in Kenya. The project included resource development, wellfield planning, a power plant and transmission lines in addition to existing wells and an interim binary power generation facility. The development project is located within a national park increasing the IFC’s environmental sensitivity based on its policy that all its operations must be environmentally and socially responsible.

Geologica Geothermal Group visited the field area to inspect the physical conditions of the site. Environmental baseline and impact assessment data, reservoir analysis and well test data were reviewed. Geologica Geothermal Group also conducted on-site interviews with the developer, local technical personnel, and government utility officials. Additional interviews included Kenya Wildlife Service personnel and other relevant environmental authorities. The capacity and productivity of the resource were evaluated to support the proposed development in the context of the existing Olkaria field. Environmental risks and adequacy of existing project environmental documentation were critical considerations in the context of local and national environmental regulatory compliance, the national park setting and the IFC’s environmental objectives. Project documentation included a written report to project and government authorities.

Coso Geothermal Area, China Lake, California Coso Reservoir Injection and Water Extraction Project-Analysis Client: MHA-RMT Inc. and Inyo County
Coso Hot Spring Monitoring Program-Annual Reporting Client: U. S. Navy Geothermal Program, Naval Air Weapons Station, China Lake, CA
Geochemical Evaluation of Coso Geothermal Reservoir Client: U. S. Navy Geothermal Program, Naval Air Weapons Station, China Lake, CA

Geologica Geothermal Group is working on three different projects related to the development of the Coso Geothermal Field, a liquid-dominated geothermal resource located in eastern California which has produced up to 265 MW annually since the mid-1980s. This field has experienced production-induced pressure drawdown and is planning to pump local groundwater to inject into the reservoir. Geologica Geothermal Group is performing an analysis of the benefit of injection, numerical simulation of the potential impacts of groundwater extraction and an evaluation of the potential geochemical and hydrological effects of increased injection on surface manifestations. In addition, Geologica Geothermal Group is preparing annual Coso Monitoring Program Reports for the U.S. Navy Geothermal Program Office (GPO) presenting hydrological, chemical, Geologica Geothermal Group and geophysical data that has been collected at Coso Hot Springs and related surrounding areas. These reports are part of the Coso Hot Springs Monitoring Program which is part of a 1979 agreement by the GPO to document changes in the physical and chemical characteristics of the Coso Hot Spring Archeological District. The data includes steam flow and groundwater levels from selected wells, physical measurements from fumaroles and mud pots, fluid chemistry for select samples, photographic documentation, local meteorological data, and for the latter two years, seismological data. Tasks included database management, data analysis, data evaluation, graphics, and reporting in conjunction with GPO staff. Geologica Geothermal Group is also performing an analysis of geochemical data collected from Coso geothermal production wells. The objective of this work is to optimize the resource development. Geologica Geothermal Group is applying existing and new tools for the interpretation of geochemical data for purposes of understanding the subsurface conditions in the Coso Geothermal reservoir. In addition, we develop and maintain GIS and database to: organize the data in a system that allows for the QA/QC of the data, transform steam +/- brine analyses into reservoir fluid chemistry under single or two-phase conditions, provide temporal and spatial analysis of the available geochemical data across the field and in individual wells over time, compare geochemical and related well production data, as well as organized data for additional interpretation. Results are reported annually.

Germencik Geothermal Field Aydin, Turkey Flow Testing: Design and Implementation Client: Gurmat Energy
Geothermal Resource Assessment and Development Feasibility Study Client: Stone & Webster-Shaw Group
Geothermal Resource Testing, Modeling and Development Support Client: Power Engineers, Inc.

Geologica Geothermal Group is currently supporting Gurmat’s resource development for their 45 MW Germencik Geothermal Project Germencik, Turkey. Geologica Geothermal Group provided resource definition, assessment, development and management services from initial short-term flow testing of six previously drilled geothermal wells in 2004 to the planning of additional wells for production and injection, to development of a conceptual and numerical model of the field and a start-up and initial production and injection and operation and maintenance plans. Short term flow testing was followed by long term production tests, injection and interference testing. Geologica Geothermal Group developed flow testing methodology, equipment specifications, performed data collection and interpretation, chemical sampling and analysis. Test results identified a commercially viable mid-enthalpy, highly permeable resource capable of supporting the proposed power generation of 25 MW net. Noncondensible gas loading and scaling potential in production and injection wells were also evaluated. Three of six wells were commercial with flow rates in excess of 400 metric tons/hour and moderate enthalpies. Flow test data recently collected by Geologica Geothermal Group worked with Gurmat to evaluate the Germencik resource as part of a feasibility study of developing the Germencik geothermal resource for 25 MW net electrical generation. The feasibility study was performed with Stone & Webster Shaw Group and partially funded by US Trade and Development Association. Our resource evaluation included identifying the number and location of injection and production wells, optimal production and injection pressures relative to well flow rates, the number of wells that need to be drilled, drilling plans, scale mitigation, noncondensible gas loading, and environmental issues and the related development costs. Germencik Flow Testing & Sampling Geologica Geothermal Group is worked with the power plant (Power Engineers) and gathering system design engineers (Veizades & Assoc.) as part of an Engineer and Procure contract to develop the Germencik 45 MW geothermal power project. Geologica Geothermal Group has provided flow test interpretation and resource evaluation of new wells, reservoir simulation, development strategy, calcite scale mitigation testing, and resource design criteria for power and gathering system design optimization. Geologica Geothermal Group helped compile data from new wells into the reservoir model, prepare start-up and initial production and injection plan, and participated in start-up of the chemical scale inhibitor systems, well production and injection wells, and the initial geochemical monitoring of the field.

Aegean Area of Western Turkey Site Review and Geothermal Resource Assessment and Development Feasibility Study Plan Client: BM

Geologica Geothermal Group began their second project in Turkey in 2008, working with BM to prepare a plan for evaluating geothermal resources and the development potential of selected geothermal areas in the Aegean area of Turkey. This work includes evaluating available Geologica Geothermal Groupl, geophysical, and geochemical information and preparing detailed step by step plans for the next exploration phase. In addition, Geologica Geothermal Groupl will prepare a plan Geothermal Resource Assessment and Development Feasibility for developing the BM geothermal resources for application to US Trade and Development Association (USTDA) for funding. Our resource evaluation will include identifying the number and location of injection and production wells, optimal production and injection pressures relative to well flow rates, the number of wells that need to be drilled, drilling plans, scale mitigation, noncondensible gas loading, and environmental issues and the related development costs.

Australian Hot Dry Rock and Oceanic Volcanic Island Hydrothermal Evaluation of Geothermal Resource Potential Using Geochemistry Client: Petratherm

Geologica Geothermal Group performed a preliminary geothermal resource evaluation of several potential geothermal resource areas using available geochemical data. Resource areas included hot dry rock prospects in Australia and traditional hydrothermal prospects related to volcanic islands. Tasks included developing geochemical exploration programs, organizing databases, data interpretation and reporting. One hot dry rock area was identified as having a signature in the nearby hot spring and deep temperatures were developed from volcanic gas chemical and isotopic signatures.

Belvedere Hot Springs Geothermal Resource Assessment and Permitting Support Client: Carol MacGregor

Geologica Geothermal Group performed a preliminary geothermal resource evaluation of a sub-boiling hot spring located on a ranch in Cascade Valley Idaho for use in direct heating and bathing. After reviewing available data and information and performing a site visit, Geologica Geothermal Group developed a conceptual model of the resource which included a fault-controlled lateral flow system confined by the Cascade Valley fault and the valley sediments. The 116-118 oF waters discharging from the spring appear to be mixed with high temperature fluids between 175 and 300 oF with maximum potential temperatures and flow sufficient to support the intended use. After presentation of the results of our resource evaluation at a hearing of the Idaho Department of Water Resources, our client was granted permission to drill and test a geothermal well on her property adjacent to the springs. We also located the first thermal well which was successfully drilling and tested.

Lihir Geothermal Field, Lihir Gold Mine, Papua New Guinea Geothermal Resource Assessment and Development Feasibility Study Client: Lihir Gold

The Lihir Geothermal resource is located in an active open pit gold mine on the Island of Lihir in Papua New Guinea. Since the mine required dewatering and temperatures were high as a result of active hydrothermal system, mine dewatering produced steam, Geologica Geothermal Group reviewed available on mine dewatering and limited deeper geothermal exploration wells as part of conducting a feasibility study of developing the Lihir geothermal resource for power generation to run the mine’s gold processing plant. Geologica Geothermal Group recommended that mine construct a 25 MW net electrical generation based on available resource after addressing scaling issues and the temporary nature of mine dewatering wells. The mine started with a smaller pilot project and is currently beginning a 25 MW power generation facility.

Darajat Steam Field, West Java, Indonesia Geochemical Analysis and Resource Evaluation Client: Amoseas Indonesia

Geologica Geothermal Group compiled and evaluated geochemical data from the Darajat Steam Field a vapor dominated geothermal resource on Java, Indonesia. Data was evaluated in order to assess reservoir saturation, identify optimal production and injection strategy for expansion from 55 to 170 MW of power generation. Geologica Geothermal Group participated in the geochemical monitoring plans and tracer test design.

Mahanagdong, Upper Mahio and Malitbog Field Power Plant Efficiency Issues Related to Steam Chemistry Client: Global Power Solutions and CalEnergy International

Geologica Geothermal Group provided an analysis of steam chemistry issues related to power plant efficiency at three separate geothermal field in the Philippines. Primary issues were turbine scaling and corrosion, gas loading and plant modifications for hydrogen sulfide abatement. Geologica Geothermal Group evaluated the records of steam and steam condensate chemistry relative to records of turbine scaling and turbine wash as well as comparing histories of noncondensible gas and hydrogen sulfide concentrations relative to design criteria.

East Mesa Geothermal Field, Imperial Valley, California Environmental and Resource Due Diligence for Geothermal Asset Sale Client: Ormat Energy Systems Inc.

Geologica Geothermal Group conducted the environmental due diligence for the East Mesa Geothermal resource purchase by Ormat Energy Systems Inc. Our work involved an extended Phase I Environmental Site Assessment and review of the overall capacity of the East Mesa resource. Preliminary data review identified key environmental issues and potential impacts related to the extensive production history at East Mesa. Several operators and separate ownership resulted in a variety of operating practices and potential impacts related to geothermal production. Geologica Geothermal Group visited the East Mesa field to evaluate the physical conditions of the site, potential environmental impacts and resource data. Geologica Geothermal Group also conducted extensive on-site interviews with the developer and local technical personnel to establish past production practices and the potential for production impacts related to the current operations. Site visits reviewed an extensive document archive related to field production history and past exploration and development operations. Recommendations were forwarded to Ormat and the asset purchase was completed in 2000.

Covanta Energy Systems Inc. Facilities at Casa Diablo and Heber, CAM Environmental and Resource Due Diligence for Geothermal Asset Sale Client : Global Power Solutions; Marin Power Corp.; Cerberus

Geologica Geothermal Group conducted the environmental and resource due diligence for more than $200m of geothermal assets owned by Covanta Energy Systems Inc. Our work involved an extended Phase I Environmental Site Assessment and overall resource review for production and generation facilities in Heber, California and Long Valley caldera. Preliminary data analysis involved extensive review of the production history at each area and the environmental documentation related to production and generation operations. Ownership transitions and differing production schemes required different operating practices at separate but related geothermal assets in Heber. Geothermal production in a very sensitive resort area required extensive monitoring and documentation in Long Valley Geologica Geothermal Group visited both geothermal fields to evaluate the physical conditions of each site, related environmental impacts and resource data. Geologica Geothermal Group also conducted on-site interviews with the developer and local technical personnel to establish production practices and the potential for environmental impacts related to the current operations. Site visits reviewed document archives related to field production history and past exploration and development operations. Geologica Geothermal Group also initiated a resource capability review to evaluate production capabilities at each field. Existing reservoir models were reviewed to establish the resource potential and probable future production capabilities for each field. Resource estimates were used to project financial rates of return for future production and probable expansion or development of additional geothermal resources.

Island of St. Vincent, St. Vincent and the Grenadines Geothermal Exploration and Environmental Baseline Geothermal Resource Assessment Client : Growth Capital Holdings , (North American Geo Power)

Geologica Geothermal Group personnel worked on the initial exploration of geothermal resources on St. Vincent Island. Our work involved two phases of geochemical sampling of cold and warm springs, fumaroles and streams, field and laboratory analysis and data interpretation after preliminary reconnaissance identified an initial exploration target area around the island’s youngest volcanic features. Analytical results were interpreted to evaluate the nature and extent of a hydrothermal system and establish the baseline water quality of the hydrological system. Typical of many underdeveloped country’s site conditions on St. Vincent required that fieldwork was conducted primarily on foot due to limited vehicular access and poor map coverage. Field logistics required importing equipment into the country and exporting all of the samples collected. The initial phase of the project focused on evaluating the geothermal development potential by identifying, sampling and analyzing surface manifestations. A second phase of sampling and analysis was conducted based on the analytical results from the first phase. The geochemistry suggested high temperature reservoir conditions, deep circulation and some contribution of volcanic derived waters in some of the surface manifestations. The geochemical data were used to outline the approximate extent of the system, locations of recharge and discharge and potential resource temperatures and contributed hydrological data to the environmental baseline studies for the project. Results and findings were presented in a report.

Medicine Lake Highlands Fourmile Hill Geothermal Development Project-Engineering Analysis for the Authority to Construct and Permit to Operate Clients: CEQA Lead Agency: Siskiyou, County Air Pollution Control District, Somach, Simons & Dunn Attorneys

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.

Bedugal, Island of Bali, Patuha, West Java, Indonesia Geothermal Resource Characterization and Water Quality Investigations Clients: California Energy International, Ltd., Bali Energy Company, Ltd., Patuha Power, Ltd.

Geologica Geothermal Group personnel conducted investigations of surface water chemistry in two potential geothermal energy development areas in Indonesia. Investigations at Patuha included reconnaissance to identify geothermal features, geochemical sampling of hot spring, furmaroles and cold background water, field and laboratory analysis, and interpretation of results. Our investigation was an integral part of a multidisciplinary exploration project to define and characterize this resource. The Bali effort involved similar investigations of the geothermal surface manifestations as well as non-thermal lake and stream surveys along the flanks of the largest volcanic feature on the Island of Bali. Both investigations utilized local technical and logistical support and were conducted primarily on foot due to limited access and minimal road development. Sampling equipment had to be imported and samples were exported for analyses overseas. Interpretations of the Bali and Patuha geochemical data provided preliminary resource characterizations evaluation of potential reservoir conditions (single or two-phase), approximate reservoir temperatures, potential recharge and discharge, and estimated extent. Deep drilling confirmed the preliminary resource characterization partly based on our geochemical investigation and interpretation in both areas.

Long Valley Caldera, Mammoth Lakes, California Geothermal Resource Characterization, Water Quality Investigations Clients: Mono County Energy Management, Mammoth-Pacific Ltd., EDAW Inc

Geologica Geothermal Group personnel have participated in environmental baseline and monitoring studies in Long Valley caldera and the Mono basin in eastern California for more than 15 years. The region is an extremely sensitive geothermal development target bordered by wilderness areas, national park land, a national monument and a very environmentally aroused tourist community. Geologica Geothermal Group personnel have prepared, contributed to or acted as professional reviewers for three separate detailed environmental assessments for geothermal development. Our scientists have collected environmental baseline data, geochemical data and baseline biota monitoring information for numerous leasing and decision documents for the region. Our involvement included participation in a long-term cooperative program to monitor the thermal and non-thermal effects of development in Long Valley. Based on our experience, Geologica Geothermal Group has been selected as the Mono County Energy Management Department consultant to review documentation for the current development, prepare part of an Environmental Impact Report for another power plant and evaluate monitoring and numerical simulation studies to determine the potential effects of expanded development of the Casa Diablo reservoir.

Newberry Volcano, Deschutes County, Oregon Geothermal Resource Characterization, Environmental Assessments Clients: MHA Environmental Consulting Inc., Northwest Geothermal Company

Geologica Geothermal Group personnel reviewed environmental baseline and monitoring studies in Newberry volcanic complex in eastern Oregon. The proposed development borders a national park and has been the subject of detailed environmental scrutiny during several phases of development proposals. Geologica Geothermal Group prepared geologic hazards, hydrogeology and environmental impact evaluations for an environmental assessment prepared by MHA Consultants for geothermal exploration drilling and potential development. Our involvement included evaluation of baseline surveys, past environmental documentation and recent published data on Newberry Volcano. Documentation for the Environmental Assessment has been prepared and will be submitted to federal agencies for review in the near future.