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The present article proposes a novel smart building energy system utilizing deep geothermal resources through naturally-driven borehole thermal energy storage interacting with the district heating network. It includes an intelligent control strategy for lowering operational costs, making better use of renewables, and avoiding CO2 emissions by eliminating heat pumps and cooling machines to address the heating and cooling demands of a commercial building in Uppsala, a city near Stockholm, Sweden. After comprehensively conducting techno-environmental and economic assessments, the system is fine-tuned using artificial neural networks (ANN) for optimization. The study aims to determine which ANN design and training procedure is the most efficient in terms of accuracy and computing speed. It also assesses well-known optimization algorithms using the TOPSIS decision-making technique to find the best trade-off among various indicators. According to the parametric results, deeper boreholes can collect more geothermal energy and reduce CO2 emissions. However, deep drilling becomes more expensive overall, suggesting the need for multi-objective optimization to balance costs and techno-environmental benefits. The results indicate that Levenberg-Marquardt algorithms offer the optimum trade-off between computation time and error minimization. From a TOPSIS perspective, while the dragonfly algorithm is not ideal for optimizing the suggested system, the non-dominated sorting genetic algorithm is the most efficient since it yields more ideal points rated below 100. The optimization yields a higher energy production of 120 kWh/m2, as well as a decreased levelized cost of energy of 57 $/MWh, a shorter payback period of two years, and a reduced CO2 index of 1.90 kg/MWh. The analysis reveals that despite the high investment costs of 382.50 USD/m2, the system is financially beneficial in the long run due to a short payback period of around eight years, which aligns with the goals of futu

In the field of deep geothermal energy, the mono-tube design will be increasingly used in the future, as significant cost savings can be expected in the production of boreholes up to depths of 6000 m. The previously used bolting of the pipe lengths by means of sleeves contributes significantly to the construction costs. In addition, there is an increased risk of failure for the sleeve bolting, especially if different materials have to be used in different layers for the purpose of increasing the corrosion resistance. Magnetically Impelled Arc Butt Welding (MIAB) was used for direct welding of pipe segments with complete elimination of socket bolting. In the process, the casing material (L80 Type 1), which is a cost-effective standard material, and a corrosion-resistant duplex steel (1.4462) were hybrid welded. The results show excellent properties both in terms of mechanical properties and corrosion resistance. It is shown that the advantages of the MIAB process in joining these different materials can successfully overcome the metallurgical challenges. This new approach for the production of borehole liners can contribute significantly to cost reduction in the construction of geothermal boreholes.

Evaluations and interpretations of reservoir productivity are frequent in geothermal, groundwater and hydrocarbon research and applications. In this study, we consider the closure of fractures around production wells due to compaction that can affect the productivity value, i.e. the ability of subsurface formations for transporting the desired fluid to a borehole. We introduce analytical tools to evaluate and predict changes in the productivity of a deformable fractured porous media. We propose analytical models for three geometries: a rectangular fracture with zero/non-zero orientation and a circular fracture with zero orientation to maximum horizontal stress. An advanced numerical model is utilised to evaluate the impact of spatial variation of fracture aperture induced by the fracture deformation on well productivity. The developed analytical solutions using a uniform fracture aperture always either over- or underestimate the production rate. Hence, an equivalent aperture model is developed for the fracture with aperture distribution under variable contact stresses to circumvent this problem. The proposed equivalent aperture model reduces the average and maximum errors of production-rate prediction from 28% to 0.6% and from 116% to 25%, respectively. We further employ the proposed model for sensitivity analyses to illustrate the impacts of in-situ and human-controlled parameters on productivity reduction. These analyses present that the interactions among initial reservoir pressure, fracture orientation, fracture stiffness, and well pressure control productivity reduction behaviours and the maximum productivity reduction values., Petroleum Engineering

Evaluations and interpretations of reservoir productivity are frequent in geothermal, groundwater and hydrocarbon research and applications. In this study, we consider the closure of fractures around production wells due to compaction that can affect the productivity value, i.e. the ability of subsurface formations for transporting the desired fluid to a borehole. We introduce analytical tools to evaluate and predict changes in the productivity of a deformable fractured porous media. We propose analytical models for three geometries: a rectangular fracture with zero/non-zero orientation and a circular fracture with zero orientation to maximum horizontal stress. An advanced numerical model is utilised to evaluate the impact of spatial variation of fracture aperture induced by the fracture deformation on well productivity. The developed analytical solutions using a uniform fracture aperture always either over- or underestimate the production rate. Hence, an equivalent aperture model is developed for the fracture with aperture distribution under variable contact stresses to circumvent this problem. The proposed equivalent aperture model reduces the average and maximum errors of production-rate prediction from 28% to 0.6% and from 116% to 25%, respectively. We further employ the proposed model for sensitivity analyses to illustrate the impacts of in-situ and human-controlled parameters on productivity reduction. These analyses present that the interactions among initial reservoir pressure, fracture orientation, fracture stiffness, and well pressure control productivity reduction behaviours and the maximum productivity reduction values., Reservoir Engineering

Evaluations and interpretations of reservoir productivity are frequent in geothermal, groundwater and hydrocarbon research and applications. In this study, we consider the closure of fractures around production wells due to compaction that can affect the productivity value, i.e. the ability of subsurface formations for transporting the desired fluid to a borehole. We introduce analytical tools to evaluate and predict changes in the productivity of a deformable fractured porous media. We propose analytical models for three geometries: a rectangular fracture with zero/non-zero orientation and a circular fracture with zero orientation to maximum horizontal stress. An advanced numerical model is utilised to evaluate the impact of spatial variation of fracture aperture induced by the fracture deformation on well productivity. The developed analytical solutions using a uniform fracture aperture always either over- or underestimate the production rate. Hence, an equivalent aperture model is developed for the fracture with aperture distribution under variable contact stresses to circumvent this problem. The proposed equivalent aperture model reduces the average and maximum errors of production-rate prediction from 28% to 0.6% and from 116% to 25%, respectively. We further employ the proposed model for sensitivity analyses to illustrate the impacts of in-situ and human-controlled parameters on productivity reduction. These analyses present that the interactions among initial reservoir pressure, fracture orientation, fracture stiffness, and well pressure control productivity reduction behaviours and the maximum productivity reduction values.

A mathematical model for the operation of an open geothermal cyclic system for two wells is presented. The production well is supposed to pump hot water from an underground geothermal reservoir. After the use for heating purposes the cooled water is pumped back into the aquifer through the injection well. Various options related to the seasonal needs for hot water are investigated for operating such a system. During the summer months hot water is required in less quantitites. The results of numerical calculations show that it is possible to choose such modes for greater efficiency and increase the time of operation of such a system. © Published under licence by IOP Publishing Ltd.

The Reykjanes Geothermal System (RGS) is a high-temperature geothermal system located on the Reykjanes peninsula, a transtensional plate-boundary zone located on the southwestern tip of Iceland. The area is characterized by high seismicity, recent volcanism, and high-temperature geothermal fields. We use seismic noise records from April 2014 to August 2015 to study stress changes and potential deformation of the subsurface caused by injection and production operations at RGS through seismic interferometry. We retrieve continuous time series of waveform similarity values and seismic velocity changes during this period. The S-transform of the similarity values allows us to clearly identify three variations in the mechanical properties of the Reykjanes peninsula related to rapid changes of RGS production. In addition, we observe a slow seismic velocity decrease of 0.36%/year in the reservoir due to the water deficit and seasonal variations associated with the energy production demand. ©2019. American Geophysical Union. All Rights Reserved.

Arsenic (As) contamination in terrestrial geothermal systems has been identified in many countries worldwide. Concentrations higher than 0.01mg/L are detrimental to human health. We examined potential consequences for As contamination of freshwater resources based on hydrogeochemical investigations of geothermal waters in deep wells and hot springs collected from western Anatolia, Turkey. We analyzed samples for major ions and trace element concentrations. Temperature of geothermal waters in deep wells showed extreme ranges (40 and 230°C), while, temperature of hot spring fluids was up to 90°C. The Piper plot illustrated two dominant water types: Na-HCO3 - type for geothermal waters in deep wells and Ca-HCO3 - type for hot spring fluids. Arsenic concentration ranged from 0.03 to 1.5mg/L. Dominance of reduced As species, i.e., As(III), was observed in our samples. The Eh value ranged between -250 and 119mV, which suggests diverse geochemical conditions. Some of the measured trace elements were found above the World Health Organization guidelines and Turkish national safe drinking water limits. The variation in pH (range: 6.4-9.3) and As in geothermal waters suggest mixing with groundwater. Mixing of geothermal waters is primarily responsible for contamination of freshwater resources and making them unsuitable for drinking or irrigation., QC 20140117

At present, the worldwide geothermal energy production provides less than 1% of the world's energy needs but the geothermal resources confined in the first 6 km of the earth's crust are estimated to be in the fairly above 200 GW of which 50-80 GW are located in Europe. Exploring and developing at large scale untapped hydrothermal resources represent a major challenge for geothermal energy development worldwide. Several workflow processes, procedures and techniques are currently applied to locate and assess the geothermal potential in various geological contexts: sediments, volcanic, granites and metamorphic. Models and tools has been developed to forecast the performance of a green field geothermal project, but many uncertainties determine relevant risks for the investors in all the different phases of the single project and mainly in the exploration phase. The uncertainties are mainly related to the technical and economical performance (e.g. resource characteristics, the efficiency of power conversion systems, energy market conditions) but the environmental sustainability and the social acceptance might represent potential hurdles for the project development. This paper describes an innovative approach for risk assessment and mitigation applied for the exploration of green field geothermal projects. A holistic multi criteria analysis is applied to calculate the risk index of the project based on: a) resource characteristics (e.g. depth, temperature and sustainability along the whole life of the project), b) technological solution for power conversion systems (e.g. electricity and/or heat generation), c) market conditions (e.g. electricity price, tax regimes), d) the environmental and social factors (e.g. air emission, induced seismicity, natural parks). A guideline is proposed for the identification and ranking of the most promising areas suitable for sustainable geothermal project development in Europe.

TMKs: (3) 1-2-010:003 & (3) 1-2-010:001, "Prepared for Engineering Division, Department of Land and Natural Resources, State of Hawaii", "[DLNR], Engineering Division, contracted Oceanit to plug two geothermal wells in Puna, KAI-1 and SOH-4. Oceanit subcontracted the Geothermal Resource Group to assist in the highly specialized technical aspects of the well plugging job. As the job progressed it became evident that the drilling site would also need to be partially restored. To aid in this effort, Oceanit subcontracted Park Engineering to provide a topographic map of the KA1-1 well site and reservoir basin. Oceanit used this information to design a grading plan for the site. In addition, Oceanit obtained the necessary permits for the plugging and site restoration. These permits including an Individual NPDES, County grading permit and well abandonment permits."

TMKs: (3) 1-2-010:003 & (3) 1-2-010:001, "Prepared for Engineering Division, Department of Land and Natural Resources, State of Hawaii", "[DLNR], Engineering Division, contracted Oceanit to plug two geothermal wells in Puna, KAI-1 and SOH-4. Oceanit subcontracted the Geothermal Resource Group to assist in the highly specialized technical aspects of the well plugging job. As the job progressed it became evident that the drilling site would also need to be partially restored. To aid in this effort, Oceanit subcontracted Park Engineering to provide a topographic map of the KA1-1 well site and reservoir basin. Oceanit used this information to design a grading plan for the site. In addition, Oceanit obtained the necessary permits for the plugging and site restoration. These permits including an Individual NPDES, County grading permit and well abandonment permits."

TMKs: (3) 1-2-010:003 & (3) 1-2-010:001, "Prepared for Engineering Division, Department of Land and Natural Resources, State of Hawaii", "[DLNR], Engineering Division, contracted Oceanit to plug two geothermal wells in Puna, KAI-1 and SOH-4. Oceanit subcontracted the Geothermal Resource Group to assist in the highly specialized technical aspects of the well plugging job. As the job progressed it became evident that the drilling site would also need to be partially restored. To aid in this effort, Oceanit subcontracted Park Engineering to provide a topographic map of the KA1-1 well site and reservoir basin. Oceanit used this information to design a grading plan for the site. In addition, Oceanit obtained the necessary permits for the plugging and site restoration. These permits including an Individual NPDES, County grading permit and well abandonment permits."

For geothermal exploration and the development of enhanced geothermal systems (EGS) knowlegde of temperature at drillable depth is a prerequisite for site selection. Equally important is the thermo-mechanical signature of the lithosphere and crust which allow to obtain critical constraints for the crustal stress field and basement temperatures where borehole observations are rare. The stress and temperature field in Europe is subject to strong spatial variations which can be linked to polyphase extensional and compressional reactivation of the lithosphere, in different modes of deformation. In this paper we review key thermo-mechanical processes which influence the thermal state and the stress conditions in Europe. The development of innovative combinations of numerical and analogue modeling techniques is a key to thoroughly understand the spatial and temporal variations in crustal stress and temperature. For selected tectonic settings, marked by a specific deformation style, we discuss the relationship between key-factors in tectonic evolution and geothermal prospectivity. This relationship allows to approach in a rational fashion continent-scale exploration for geothermal resources and building hypothesis for thermal and mechanical characterization at depth. Further, through using deep subsurface lithosphere scale data and processes, the approach delivers valuable exploration constraints on the thermo-mechanical signature at deep depth levels and regions where near surface data is not reliable.

In the recent years the use of geothermal energy through implementation of low enthalpy geothermal production systems for both electricity and heating have been growing rapidly in north-western Europe. Geothermal exploration and production takes largely place in sedimentary basins at depths from 2 to 5 km. Geothermal activities can take considerable advantage of a wealth of existing oil and gas data. To governmental bodies, such as geological surveys, it is a major challenge to put relevant oil and gas data and derived subsurface structural, temperature, and flow property models available to the geothermal community and to facilitate in quantitative assessment of geothermal potential of targeted areas, for both heat and electricity production (EGS) . In order to face this challenge, TNO has developed a public web-based 3D information system connected to a geothermal performance assessment tool. The public information system (thermoGIS) includes high resolution 3D geological models covering the complete onshore of the Netherlands, outlining key geothermal reservoirs and allowing to assess relevant parameters and underlying uncertainties therein. State-of-the-art 3D modeling techniques have been used and developed to obtain the reservoir structures, flow properties and temperatures, using constraints from over a thousand deep wells, and detailed subsurface mapping from 3D and 2D seismic. Users can obtain key reservoir parameters, and underlying uncertainties at any location and for any reservoir. In an automated workflow these parameters are fed into the performance assessment tool, in order to asses the probability of success to meet minimum requirements on key performance indicators such as Coefficient of Performance (COP), power produced, and Unit Technical Cost (UTC). The use of the ThermoGIS will aid exploration business decisions and Dutch governmental institutions, law makers and insurance companies.

"Application for HAR, Chapter 11-55 - NPDES Individual Permit Authorizing Discharges of Storm Water Associated With Construction Activities ...", Supporting documents include maps of Big Island, blueprints, "Drainage report : KA1-1 geothermal well site restoration, Puna district, Hawaii, Hawaii," "KA1-1, SOH-4 geothermal well plugging and abandonment, Puna district, Hawaii, Hawaii : Job No. J38CH20A," "Construction BMPs plan," "Erosion control plan," and "Erosion control blanket specifications.", "Prepared for Department of Health Clean Water Branch, State of Hawaii."

"Application for HAR, Chapter 11-55 - NPDES Individual Permit Authorizing Discharges of Storm Water Associated With Construction Activities ...", Supporting documents include maps of Big Island, blueprints, "Drainage report : KA1-1 geothermal well site restoration, Puna district, Hawaii, Hawaii," "KA1-1, SOH-4 geothermal well plugging and abandonment, Puna district, Hawaii, Hawaii : Job No. J38CH20A," "Construction BMPs plan," "Erosion control plan," and "Erosion control blanket specifications.", "Prepared for Department of Health Clean Water Branch, State of Hawaii."

"Application for HAR, Chapter 11-55 - NPDES Individual Permit Authorizing Discharges of Storm Water Associated With Construction Activities ...", Supporting documents include maps of Big Island, blueprints, "Drainage report : KA1-1 geothermal well site restoration, Puna district, Hawaii, Hawaii," "KA1-1, SOH-4 geothermal well plugging and abandonment, Puna district, Hawaii, Hawaii : Job No. J38CH20A," "Construction BMPs plan," "Erosion control plan," and "Erosion control blanket specifications.", "Prepared for Department of Health Clean Water Branch, State of Hawaii."

1 map : color, Shows the geothermal wells in lower Puna.

1 map : color, Shows the geothermal wells in lower Puna.

1 map : color, Shows the geothermal wells in lower Puna.

Enclosed: cover letter that states DLNR approved this proposal., "The HGP-A well was temporarily plugged in December 1994 in a manner that allowed the cased well bore to be used while preventing geothermal fluids from reaching surface. Now the decision has been made to plug and abandon the well. In order to meet the DLNR regulations for well abandonment, the temporary plug should be removed from the well bore. Then the well bore through the geothermal producing zones can be plugged. Any attempt to do so in 1994 would have been premature, as plugging through the producing zones would have rendered the well useless for any further scientific work in the productive interval. The existing plug should be removed so that the well bore can be plugged through the producing zones. The casing above the geothermal zones will also have to be plugged to complete the abandonment.", Prepared for the Natural Energy Laboratory of Hawaii.

Enclosed: cover letter that states DLNR approved this proposal., "The HGP-A well was temporarily plugged in December 1994 in a manner that allowed the cased well bore to be used while preventing geothermal fluids from reaching surface. Now the decision has been made to plug and abandon the well. In order to meet the DLNR regulations for well abandonment, the temporary plug should be removed from the well bore. Then the well bore through the geothermal producing zones can be plugged. Any attempt to do so in 1994 would have been premature, as plugging through the producing zones would have rendered the well useless for any further scientific work in the productive interval. The existing plug should be removed so that the well bore can be plugged through the producing zones. The casing above the geothermal zones will also have to be plugged to complete the abandonment.", Prepared for the Natural Energy Laboratory of Hawaii.

Enclosed: cover letter that states DLNR approved this proposal., "The HGP-A well was temporarily plugged in December 1994 in a manner that allowed the cased well bore to be used while preventing geothermal fluids from reaching surface. Now the decision has been made to plug and abandon the well. In order to meet the DLNR regulations for well abandonment, the temporary plug should be removed from the well bore. Then the well bore through the geothermal producing zones can be plugged. Any attempt to do so in 1994 would have been premature, as plugging through the producing zones would have rendered the well useless for any further scientific work in the productive interval. The existing plug should be removed so that the well bore can be plugged through the producing zones. The casing above the geothermal zones will also have to be plugged to complete the abandonment.", Prepared for the Natural Energy Laboratory of Hawaii.

Submitted to Manabu Tagomori, Chief Engineer, Department of Land and Natural Resources.

Submitted to Manabu Tagomori, Chief Engineer, Department of Land and Natural Resources.

Submitted to Manabu Tagomori, Chief Engineer, Department of Land and Natural Resources.

This report covers the work accomplished by Elizabeth A. Novak during reporting period 6/1/92 through1/31/93., "Objectives The objectives of the geochemistry subtask are as follows: 1) Conduct monitoring and sampling of the shallow groundwater system in lower Puna to develop a baseline data base for the chemical and physical quality of the water prior to and during the planned development of the geothermal resource; 2) Provide independent analysis of geothermal fluids from all exploration wells that are drilled and tested during the commercial development of the geothermal resource; 3) Provide analyses of groundwater wells that are drilled in other areas of Hawaii where geothermal discharges are thought to exist in order to develop baseline data for the range of geothermal fluid compositions found in Hawaii."

Data for these wells: KS-1, KS-3, KS-4, KS-7, KS-8, KS-9, MW-1, MW-2, Data includes temperature, pressure, fluid injection, chemical, and drilling.

This report covers the work accomplished by Elizabeth A. Novak during reporting period 6/1/92 through1/31/93., "Objectives The objectives of the geochemistry subtask are as follows: 1) Conduct monitoring and sampling of the shallow groundwater system in lower Puna to develop a baseline data base for the chemical and physical quality of the water prior to and during the planned development of the geothermal resource; 2) Provide independent analysis of geothermal fluids from all exploration wells that are drilled and tested during the commercial development of the geothermal resource; 3) Provide analyses of groundwater wells that are drilled in other areas of Hawaii where geothermal discharges are thought to exist in order to develop baseline data for the range of geothermal fluid compositions found in Hawaii."

This report covers the work accomplished by Elizabeth A. Novak during reporting period 6/1/92 through1/31/93., "Objectives The objectives of the geochemistry subtask are as follows: 1) Conduct monitoring and sampling of the shallow groundwater system in lower Puna to develop a baseline data base for the chemical and physical quality of the water prior to and during the planned development of the geothermal resource; 2) Provide independent analysis of geothermal fluids from all exploration wells that are drilled and tested during the commercial development of the geothermal resource; 3) Provide analyses of groundwater wells that are drilled in other areas of Hawaii where geothermal discharges are thought to exist in order to develop baseline data for the range of geothermal fluid compositions found in Hawaii."

Data for these wells: KS-1, KS-3, KS-4, KS-7, KS-8, KS-9, MW-1, MW-2, Data includes temperature, pressure, fluid injection, chemical, and drilling.

Memo "Puna Geothermal Venture: MW-3 and KS-8 wells" dated 08/30/91 attached.

The color photographs show the geothermal well site and the surrounding area.

Memo "Puna Geothermal Venture: MW-3 and KS-8 wells" dated 08/30/91 attached.

"The KS-8 well test is designed to determine the flow characteristics of production well KS-8. Major components for the power plant and the gathering and disposal system including injection well KS-3 will also be tested as part of this program. The well test program described in this document consists of the following elements: * KS-8 well test program procedures, equipment, and instrumentation. * H2S abatement program to be used during the well test. * Chemical sampling program for the analysis of geothermal brine, stearn, and non-condensible gases including toxic elements. * Chemical sampling program for the analysis of aerosols emitted from the stearn rock muffler. * Test program for power plant components using stearn from KS-8 during the flow test. * Program for injecting geothermal brine from the main separator into injection well KS-3. Vertical venting for initial well cleanout will not be used in the KS-8 well test. Instead, the initial water-rich flow from the well will be vented through an atmospheric separator/muffler. H2S will be abated in the stearn fraction throughout the test including the initial cleanout period."

The color photographs show the geothermal well site and the surrounding area.

"During the drilling of injection well KS-7, the Puna Geothermal Venture has encountered a high temperature, high pressure zone at depth of 1600'. This zone caused the fluid and steam release on the afternoon of February 21, 1991. Since that time the well has been shut in and is being kept in a stable condition by continuous pumping of cold water into the well bore. During this period equipment and personnel were assembled in order to plug the well. PGV is hereby requesting authorization to execute plugging and monitoring operations that we feel are required to bring the well to a stable and safe condition for the long term. This program is described in the attached document and figures."

"The KS-8 well test is designed to determine the flow characteristics of production well KS-8. Major components for the power plant and the gathering and disposal system including injection well KS-3 will also be tested as part of this program. The well test program described in this document consists of the following elements: * KS-8 well test program procedures, equipment, and instrumentation. * H2S abatement program to be used during the well test. * Chemical sampling program for the analysis of geothermal brine, stearn, and non-condensible gases including toxic elements. * Chemical sampling program for the analysis of aerosols emitted from the stearn rock muffler. * Test program for power plant components using stearn from KS-8 during the flow test. * Program for injecting geothermal brine from the main separator into injection well KS-3. Vertical venting for initial well cleanout will not be used in the KS-8 well test. Instead, the initial water-rich flow from the well will be vented through an atmospheric separator/muffler. H2S will be abated in the stearn fraction throughout the test including the initial cleanout period."

"During the drilling of injection well KS-7, the Puna Geothermal Venture has encountered a high temperature, high pressure zone at depth of 1600'. This zone caused the fluid and steam release on the afternoon of February 21, 1991. Since that time the well has been shut in and is being kept in a stable condition by continuous pumping of cold water into the well bore. During this period equipment and personnel were assembled in order to plug the well. PGV is hereby requesting authorization to execute plugging and monitoring operations that we feel are required to bring the well to a stable and safe condition for the long term. This program is described in the attached document and figures."

The color photographs show the geothermal well site and the surrounding area.

"The KS-8 well test is designed to determine the flow characteristics of production well KS-8. Major components for the power plant and the gathering and disposal system including injection well KS-3 will also be tested as part of this program. The well test program described in this document consists of the following elements: * KS-8 well test program procedures, equipment, and instrumentation. * H2S abatement program to be used during the well test. * Chemical sampling program for the analysis of geothermal brine, stearn, and non-condensible gases including toxic elements. * Chemical sampling program for the analysis of aerosols emitted from the stearn rock muffler. * Test program for power plant components using stearn from KS-8 during the flow test. * Program for injecting geothermal brine from the main separator into injection well KS-3. Vertical venting for initial well cleanout will not be used in the KS-8 well test. Instead, the initial water-rich flow from the well will be vented through an atmospheric separator/muffler. H2S will be abated in the stearn fraction throughout the test including the initial cleanout period."

"During the drilling of injection well KS-7, the Puna Geothermal Venture has encountered a high temperature, high pressure zone at depth of 1600'. This zone caused the fluid and steam release on the afternoon of February 21, 1991. Since that time the well has been shut in and is being kept in a stable condition by continuous pumping of cold water into the well bore. During this period equipment and personnel were assembled in order to plug the well. PGV is hereby requesting authorization to execute plugging and monitoring operations that we feel are required to bring the well to a stable and safe condition for the long term. This program is described in the attached document and figures."

Memo "Puna Geothermal Venture: MW-3 and KS-8 wells" dated 08/30/91 attached.

"On 12 August 1990 a botanical survey was conducted of the proposed new Well Site adjacent to the access road to Well Site 1."

"On 15 December 1989 a botanical survey was conducted of the proposed Well Site 2 and its access road from Well Site 1. On 13 January 1990 a similar survey was conducted of the proposed Well Site 3 and its access road from Well Site 1."

"On 12 August 1990 a botanical survey was conducted of the proposed new Well Site adjacent to the access road to Well Site 1."

This report presents the results of a field survey for birds along the proposed access roads to well sites 2 and 3, and on the well sites themselves, in the geothermal resource subzone, Puna Forest Reserve, Puna, Hawaii. The survey was conducted on 16 February 1990."