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Borehole Summary Report for Waste Treatment Plant Seismic Borehole C4993

Description: A core hole (C4998) and three boreholes (C4993, C4996, and C4997) were drilled to acquire stratigraphic and downhole seismic data to model potential seismic impacts and to refine design specifications and seismic criteria for the Waste Treatment Plant (WTP) under construction on the Hanford Site. Borehole C4993 was completed through the Saddle Mountains Basalt, the upper portion of the Wanapum Basalt, and associated sedimentary interbeds, to provide a continuous record of the rock penetrated by all four holes and to provide access to the subsurface for geophysical measure¬ment. Presented and compiled in this report are field-generated records for the deep mud rotary borehole C4993 at the WTP site. Material for C4993 includes borehole logs, lithologic summary, and record of rock chip samples collected during drilling through the months of August through early October. The borehole summary report also includes documentation of the mud rotary drilling, borehole logging, and sample collection.
Date: February 28, 2007
Creator: Rust, Colleen F.; Barnett, D. BRENT; Bowles, Nathan A. & Horner, Jake A.
Partner: UNT Libraries Government Documents Department

Scientific drilling into the San Andreas fault and site characterization research: Planning and coordination efforts. Final technical report

Description: The fundamental scientific issue addressed in this proposal, obtaining an improved understanding of the physical and chemical processes responsible for earthquakes along major fault zones, is clearly of global scientific interest. By sampling the San Andreas fault zone and making direct measurements of fault zone properties to 4.0 km at Parkfield they will be studying an active plate-boundary fault at a depth where aseismic creep and small earthquakes occur and where a number of the scientific questions associated with deeper fault zone drilling can begin to be addressed. Also, the technological challenges associated with drilling, coring, downhole measurements and borehole instrumentation that may eventually have to be faced in deeper drilling can first be addressed at moderate depth and temperature in the Parkfield hole. Throughout the planning process leading to the development of this proposal they have invited participation by scientists from around the world. As a result, the workshops and meetings they have held for this project have involved about 350 scientists and engineers from about a dozen countries.
Date: August 30, 1998
Creator: Zoback, M. D.
Partner: UNT Libraries Government Documents Department

Use of Downhole Motors in Geothermal Drilling in the Philippines

Description: This paper describes the use of downhole motors in the Tiwi geothermal field in the Philippines, The discussion includes the application Of a Dyna-Drill with insert-type bits for drilling through surface alluvium. The economics of this type of drilling are compared to those of conventional rotary drilling. The paper also describes the use of a turbodrill that drills out scale as the well produces geothermal fluids.
Date: January 1, 1981
Creator: Pyle, D. E.
Partner: UNT Libraries Government Documents Department

Specific energy for laser removal of rocks.

Description: Application of advanced high power laser technology into oil and gas well drilling has been attracting significant research interests recently among research institutes, petroleum industries, and universities. Potential laser or laser-aided oil and gas well drilling has many advantages over the conventional rotary drilling, such as high penetration rate, reduction or elimination of tripping, casing, and bit costs, and enhanced well control, perforating and side-tracking capabilities. The energy required to remove a unit volume of rock, namely the specific energy (SE), is a critical rock property data that can be used to determine both the technical and economic feasibility of laser oil and gas well drilling.
Date: August 16, 2001
Creator: Xu, Z.; Kornecki, G.; Reed, C. B.; Gahan, B. C.; Parker, R. A.; Batarseh, S. et al.
Partner: UNT Libraries Government Documents Department

DOE lost circulation technology development

Description: Lost circulation is a problem common in both the geothermal and the solution mining industries. In both cases, drilling is on a relatively large scale (geothermal holes can be as large as 26 inches). Lost circulation technology development for geothermal drilling has been in progress at Sandia National Laboratories for more than 15 years. The initial work centered on lost circulation materials, but testing and modeling indicated that if the aperture of a loss zone is very large (larger than the drill bit nozzles) it cannot be plugged by simply adding materials to the drilling fluid. Thus, the lost circulation work evolved to include: (1) Development of metering techniques that accurately measure and characterize drilling fluid inflow and outflow for rapid diagnosis of los circulation and/or fluid balance while drilling. (2) Construction of a laboratory facility for testing drillable straddle packers (to improve the plugging efficiency of cementing operations) and the actual testing of components of the straddle packer. (3) Construction of a laboratory facility for the testing of candidate porous fabrics as a part of a program to develop a porous packer that places polyurethane foam into a loss zone. (4) Implementing (with Halliburton and CalEnergy Company), a program to test cementitious lost circulation material as an alternative to Portland cement.
Date: September 1, 1996
Creator: Glowka, D.A.; Staller, G.E. & Sattler, A.R.
Partner: UNT Libraries Government Documents Department

Advanced drilling systems study

Description: This work was initiated as part of the National Advanced Drilling and Excavation Technologies (NADET) Program. It is being performed through joint finding from the Department of Energy Geothermal Division and the Natural Gas Technology Branch, Morgantown Energy Technology Center. Interest in advanced drilling systems is high. The Geothermal Division of the Department of Energy has initiated a multi-year effort in the development of advanced drilling systems; the National Research Council completed a study of drilling and excavation technologies last year; and the MIT Energy Laboratory recently submitted a proposal for a national initiative in advanced drilling and excavation research. The primary reasons for this interest are financial. Worldwide expenditures on oil and gas drilling approach $75 billion per year. Also, drilling and well completion account for 25% to 50% of the cost of producing electricity from geothermal energy. There is incentive to search for methods to reduce the cost of drilling. Work on ideas to improve or replace rotary drilling technology dates back at least to the 1930`s. There was a significant amount of work in this area in the 1960`s and 1970`s; and there has been some continued effort through the 1980`s. Undoubtedly there are concepts for advanced drilling systems that have yet to be studied; however, it is almost certain that new efforts to initiate work on advanced drilling systems will build on an idea or a variation of an idea that has already been investigated. Therefore, a review of previous efforts coupled with a characterization of viable advanced drilling systems and the current state of technology as it applies to those systems provide the basis for the current study of advanced drilling.
Date: March 1995
Creator: Pierce, K. G. & Livesay, B. J.
Partner: UNT Libraries Government Documents Department

Development and determination of a single-shell tank interim stabilization pumping strategy

Description: This activity plan addresses the technique and steps involved in simulating a riser installation in the dome of a single-shell waste storage tank by the used of a rotary drill rig. This simulation will provide information to avoid potential inadequacies in planning and field efforts in a nonradiological environment. Personnel can be trained in a nonradiological environmental while perfecting techniques for drilling and installing risers. It is essential that field equipment and installation procedures be perfected before the installation of risers in SSTs occurs. Time spent installing the actual risers in the SSTs will be minimized, aiding in safety of personnel and conformance to ALARA principles.
Date: June 12, 1995
Creator: Garvin, L.J. & Kujak, S.K.
Partner: UNT Libraries Government Documents Department

Directional Drilling and Equipment for Hot Granite Wells

Description: Directional drilling technology was extended and modified to drill the first well of a subsurface geothermal energy extraction system at the Fenton Hill, New Mexico, hot dry rock (HDR) experimental site. Borehole geometries, extremely hard and abrasive granite rock, and high formation temperatures combined to provide a challenging environment for directional drilling tools and instrumentation. Completing the first of the two-wellbore HDR system resulted in the definition of operation limitations of -many conventional directional drilling tools, instrumentation, and techniques. The successful completion of the first wellbore, Energy Extraction Well No. 2 (EE-21), to a measured depth of 4.7 km (15,300 ft) in granite reservoir rock with a bottomhole temperature of 320 C (610 F) required the development of a new high-temperature downhole motor and modification of existing wireline-conveyed steering tool systems. Conventional rotary-driven directional assemblies were successfully modified to accommodate the very hard and abrasive rock encountered while drilling nearly 2.6 km (8,500 ft) of directional hole to a final inclination of 35{sup o} from the vertical at the controlled azimuthal orientation. Data were collected to optimize the drilling procedures far the programmed directional drilling of well EE-3 parallel to, and 370 metres (1,200 ft) above, Drilling equipment and techniques used in drilling wellbores for extraction of geothermal energy from hot granite were generally similar to those that are standard and common to hydrocarbon drilling practices. However, it was necessary to design some new equipment for this program: some equipment was modified especially for this program and some was operated beyond normal ratings. These tools and procedures met with various degrees of success. Two types of shock subs were developed and tested during this project. However, downhole time was limited, and formations were so varied that analysis of the capabilities of these items is not conclusive. Temperature limits of the ...
Date: January 1, 1981
Creator: Williams, R. E.; Neudecker, J. W.; Rowley, J.C. & Brittenham, T. L.
Partner: UNT Libraries Government Documents Department

Geothermal Drilling and Completion Technology Development Program Annual Progress Report

Description: The high cost of drilling and completing geothermal wells is an impediment to the timely development of geothermal resources in the US. The Division of Geothermal Energy (DGE) of the Department of Energy (DOE) has initiated a development program aimed at reducing well costs through improvements in the technology used to drill and complete geothermal wells. Sandia National Laboratories (SNL) has been selected to manage this program for DOE/DGE. Based on analyses of existing well costs, cost reduction goals have been set for the program. These are to develop the technology required to reduce well costs by 25% by 1983 and by 50% by 1987. To meet these goals, technology development in a wide range of areas is required. The near-term goal will be approached by improvements in conventional, rotary drilling technology. The long-term goal will require the development of an advanced drilling and completion system. Currently, the program is emphasizing activities directed at the near-term cost reduction goal, but increased emphasis on advanced system development is anticipated as time progresses. The program is structured into six sub-elements: Drilling Hardware, Drilling Fluids, Completion Technology, Lost Circulation Control Methods, Advanced Drilling Systems, and Supporting Technology. Technology development in each of these areas is conducted primarily through contracts with private industries and universities. Some projects are conducted internally by Sandia. This report describes the program, status, and results of ongoing R and D within the program for the 1980 fiscal year.
Date: March 1, 1981
Creator: Varnado, S. G.
Partner: UNT Libraries Government Documents Department

Fundamental Research on Percussion Drilling: Improved rock mechanics analysis, advanced simulation technology, and full-scale laboratory investigations

Description: This report summarizes the research efforts on the DOE supported research project Percussion Drilling (DE-FC26-03NT41999), which is to significantly advance the fundamental understandings of the physical mechanisms involved in combined percussion and rotary drilling, and thereby facilitate more efficient and lower cost drilling and exploration of hard-rock reservoirs. The project has been divided into multiple tasks: literature reviews, analytical and numerical modeling, full scale laboratory testing and model validation, and final report delivery. Literature reviews document the history, pros and cons, and rock failure physics of percussion drilling in oil and gas industries. Based on the current understandings, a conceptual drilling model is proposed for modeling efforts. Both analytical and numerical approaches are deployed to investigate drilling processes such as drillbit penetration with compression, rotation and percussion, rock response with stress propagation, damage accumulation and failure, and debris transportation inside the annulus after disintegrated from rock. For rock mechanics modeling, a dynamic numerical tool has been developed to describe rock damage and failure, including rock crushing by compressive bit load, rock fracturing by both shearing and tensile forces, and rock weakening by repetitive compression-tension loading. Besides multiple failure criteria, the tool also includes a damping algorithm to dissipate oscillation energy and a fatigue/damage algorithm to update rock properties during each impact. From the model, Rate of Penetration (ROP) and rock failure history can be estimated. For cuttings transport in annulus, a 3D numerical particle flowing model has been developed with aid of analytical approaches. The tool can simulate cuttings movement at particle scale under laminar or turbulent fluid flow conditions and evaluate the efficiency of cutting removal. To calibrate the modeling efforts, a series of full-scale fluid hammer drilling tests, as well as single impact tests, have been designed and executed. Both Berea sandstone and Mancos shale samples are used. ...
Date: December 31, 2005
Creator: Bruno, Michael S.
Partner: UNT Libraries Government Documents Department

Deep Drilling Basic Research: Volume 4 - System Description. Final Report, November 1988--August 1990

Description: The first section of this Volume will discuss the ''Conventional Drilling System''. Today's complex arrangement of numerous interacting systems has slowly evolved from the very simple cable tool rigs used in the late 1800s. Improvements to the conventional drilling rig have varied in size and impact over the years, but the majority of them have been evolutionary modifications. Each individual change or improvement of this type does not have significant impact on drilling efficiency and economics. However, the change is almost certain to succeed, and over time--as the number of evolutionary changes to the system begin to add up--improvements in efficiency and economics can be seen. Some modifications, defined and described in this Volume as Advanced Modifications, have more than just an evolutionary effect on the conventional drilling system. Although the distinction is subtle, there are several examples of incorporated advancements that have had significantly more impact on drilling procedures than would a truly evolutionary improvement. An example of an advanced modification occurred in the late 1970s with the introduction of Polycrystalline Diamond Compact (PDC) drill bits. PDC bits resulted in a fundamental advancement in drilling procedures that could not have been accomplished by an evolutionary improvement in materials metallurgy, for example. The last drilling techniques discussed in this Volume are the ''Novel Drilling Systems''. The extent to which some of these systems have been developed varies from actually being tested in the field, to being no more than a theoretical concept. However, they all have one thing in common--their methods of rock destruction are fundamentally different from conventional drilling techniques. When a novel drilling system is introduced, it is a revolutionary modification of accepted drilling procedures and will completely replace current techniques. The most prominent example of a revolutionary modification in recent history was the complete displacement of cable ...
Date: June 1, 1990
Creator: Anderson, E.E.; Maurer, W.C.; Hood, M.; Cooper, G. & Cook, N.
Partner: UNT Libraries Government Documents Department

Microhole Coiled Tubing Bottom Hole Assemblies

Description: The original objective of the project, to deliver an integrated 3 1/8-inch diameter Measurement While Drilling (MWD) and Logging While Drilling (LWD) system for drilling small boreholes using coiled tubing drilling, has been achieved. Two prototype systems have been assembled and tested in the lab. One of the systems has been successfully tested downhole in a conventional rotary drilling environment. Development of the 3 1/8-inch system has also lead to development and commercialization of a slightly larger 3.5-inch diameter system. We are presently filling customer orders for the 3.5-inch system while continuing with commercialization of the 3 1/8-inch system. The equipment developed by this project will be offered for sale to multiple service providers around the world, enabling the more rapid expansion of both coiled tubing drilling and conventional small diameter drilling. The project was based on the reuse of existing technology whenever possible in order to minimize development costs, time, and risks. The project was begun initially by Ultima Labs, at the time a small company ({approx}12 employees) which had successfully developed a number of products for larger oil well service companies. In September, 2006, approximately 20 months after inception of the project, Ultima Labs was acquired by Sondex plc, a worldwide manufacturer of downhole instrumentation for cased hole and drilling applications. The acquisition provided access to proven technology for mud pulse telemetry, downhole directional and natural gamma ray measurements, and surface data acquisition and processing, as well as a global sales and support network. The acquisition accelerated commercialization through existing Sondex customers. Customer demand resulted in changes to the product specification to support hotter (150 C) and deeper drilling (20,000 psi pressure) than originally proposed. The Sondex acquisition resulted in some project delays as the resistivity collar was interfaced to a different MWD system and also as the ...
Date: June 30, 2008
Creator: Macune, Don
Partner: UNT Libraries Government Documents Department

A technical and economic evaluation of thermal spallation drilling technology

Description: Thermal spallation of rock may be defined as a type of progressive rock failure caused by the creation of thermal stresses induced by a sudden application of heat from a high temperature source. This technology is applicable to only certain types of hard rock, such as dolomite, taconite, and granite. In 1981 and 1982, the deepest holes ever drilled by this process were drilled in granite to depths of 1086 feet and 425 feet respectively. Penetration rates at the bottom of the deeper hole reached a maximum of 100 ft/hr. Because of these high rates, considerable interest was generated concerning the use of this technology for the drilling of deep holes. Based on this interest, this study was undertaken to evaluate the technical and economic aspects of the technology in general. This methodology has been used for blasthole drilling, the cutting of chambers at the bottom of drilled holes, and the cutting of narrow grooves in rock. However, because of the very high temperatures generated by the flame jet and the application of the technology to only certain types of rock, other areas of use have been very limited. In this report, evaluation of the technology was performed by conceptually designing and costing a theoretical flame jet drilling rig. The design process reviews a number of different concepts of the various components needed, and then chooses those pieces of equipment that best suit the needs of the system and have the best chance of being properly developed. The final concept consists of a flexible umbilical hose containing several internal hoses for carrying the various required fluids. An evaluation of this system was then made to determine its operational characteristics. The drilling capabilities and the economics of this rig were then compared to a conventional rotary drilling rig by theoretically drilling ...
Date: July 10, 1984
Partner: UNT Libraries Government Documents Department

Techniques Employed to Conduct Postshot Drilling at the former Nevada Test Site

Description: Postshot drilling provided essential data on the results of the underground nuclear tests conducted at the Nevada Test Site (NTS), now identified as the Nevada National Security Site (NNSS). It was the means by which samples from the zone of interest were obtained for radiochemical analysis. This handbook describes how Lawrence Livermore National Laboratory (LLNL) conducted postshot drilling operations at the NTS, and it provides a general understanding of the process. Postshot drilling is a specialized application of rotary drilling. Accordingly, this handbook gives a brief description of rotary drilling in Section 2 to acquaint the reader with the general subject before proceeding to the specialized techniques used in postshot drilling. In Section 3, the handbook describes the typical postshot drilling situation at the former NTS and the drilling methods used. Section 4 describes the typical sequence of operations in postshot drilling at the former NTS. Detailed information on special equipment and techniques is given in a series of appendices (A through F) at the end of the handbook.
Date: April 14, 2011
Creator: Dekin, W D
Partner: UNT Libraries Government Documents Department

Slimhole Drilling, Logging, and Completion Technology - An Update

Description: Using slim holes (diameter < 15 cm) for geothermal exploration and small-scale power production can produce significant cost savings compared to conventional rotary-drilling methods. In addition, data obtained from slim holes can be used to lower the risks and costs associated with the drilling and completion of large-diameter geothermal wells. As a prime contractor to the U.S. Department of Energy (DOE), Sandia National Laboratories has worked with industry since 1992 to develop and promote drilling, testing, and logging technology for slim holes. This paper describes the current status of work done both in-house and contracted to industry. It focuses on drilling technology, case histories of slimhole drilling projects, data collection and rig instrumentation, and high-temperature logging tools.
Date: October 7, 1999
Partner: UNT Libraries Government Documents Department

Blue Mountain, Humboldt County, Nevada, U.S.A

Description: The report documents the drilling of well Deep Blue No.2, the second deep geothermal test hole at the Blue Mountain Geothermal Area, Humboldt County, Nevada. The well was drilled by Noramex Corp, a Nevada company, with funding support from the US Department of Energy, under the DOE’s GRED II Program. Deep Blue No.2 was drilled as a ‘step-out’ hole from Deep Blue No.1, to further evaluate the commercial potential of the geothermal resource. Deep Blue No.2 was designed as a vertical, slim observation test hole to a nominal target depth of 1000 meters (nominal 3400 feet). The well tests an area of projected high temperatures at depth, from temperature gradients measured in a group of shallow drill holes located approximately one kilometer to the northeast of observation hole Deep Blue No.1. The well is not intended for, or designed as, a commercial well or a production well. Deep Blue No.2 was spudded on March 25, 2004 and completed to a total depth of 1127.76m (3700 ft) on April 28, 2004. The well was drilled using conventional rotary drilling techniques to a depth of 201.17 m (660 ft), and continuously cored from 201.17m (660 ft) to 1127.76m (3700 ft). A brief rig-on flow-test was conducted at completion to determine basic reservoir parameters and obtain fluid samples. A permeable fracture zone with measured temperatures of 150 to 167°C (302 to 333°F) occurs between 500 to 750m (1640 to 2461ft). The well was left un-lined in anticipation of the Phase III - Flow and Injection Testing. A further Kuster temperature survey was attempted after the well had been shut in for almost 3 weeks. The well appears to have bridged off at 439m (1440ft) as the Kuster tool was unable to descend past this point. Several attempts to dislodge the obstruction using tube ...
Date: April 1, 2005
Creator: Ted Fitzpatrick, Brian D. Fairbank
Partner: UNT Libraries Government Documents Department

Final report, Grace Geothermal Corporation, Baltazor Hot Springs, Nevada, Hole No. 45-14

Description: During the period from September 21, 1982 to November 1, 1982 one geothermal test well was drilled within the Baltazor Hot Springs KGRA in northwestern Nevada to a total depth of 2529 feet (Figure 1). Temperature-depth profiles from two temperature surveys run in the open hole are presented in Figure 2. The maximum temperature recorded was 223.77 F at a total survey depth of 2430 feet. Geothermal gradients from selected intervals in the well ranged from 2.25 F/100 ft to 11.00 F/100 ft. Individual temperature-depth plots, gradient plots, and interval gradient plots are provided in Appendix A. Rock types encountered ranged from unconsolidated alluvium to rhyolitic and basaltic flows, tuffs and flow breccias. A lithologic section for the well is provided in a pocket at the back of the report (Figure 3). Thermal conductivity measurements were performed on a total of 26 drill cutting samples that ranged from 2.9 TCU to 5.5 TCU (1 TCU = 1 mcal/cm-sec-deg C) and are presented in Appendix B. Selected heat flow data for the well are provided in Table 1. Well 45-14 was drilled by Southwest Drilling and Exploration, Inc., utilizing a Gardner Denver 2000 rotary drilling machine with a 53 foot mast rated at 100,000 lbs. capacity. Drilling conditions ranged from moderate to difficult with the major problems resulting from the hard and fractured rhyolite sequence in the upper part of the well. Drilling rates below 1750 feet were greatly reduced as a result of decreasing the weight on the bit to keep the vertical deviation within the required 4 degrees. Fluid losses were contained to a minimum below the rhyolite sequence and did not present a major problem. Selected drilling data and a detailed drilling history are provided in Appendix C. Earth Power Production Company completed two test holes in the ...
Date: January 1, 1983
Creator: Helms, Bart & Williams, Barry
Partner: UNT Libraries Government Documents Department

Geologic investigation of Playa Lakes, Tonopah Test Range, Nevada : data report.

Description: Subsurface geological investigations have been conducted at two large playa lakes at the Tonopah Test Range in central Nevada. These characterization activities were intended to provide basic stratigraphic-framework information regarding the lateral distribution of ''hard'' and ''soft'' sedimentary materials for use in defining suitable target regions for penetration testing. Both downhole geophysical measurements and macroscopic lithilogic descriptions were used as a surrogate for quantitative mechanical-strength properties, although some quantitative laboratory strength measurements were obtained as well. Both rotary (71) and core (19) holes on a systematic grid were drilled in the southern half of the Main Lake; drill hole spacings are 300 ft north-south and 500-ft east-west. The drilled region overlaps a previous cone-penetrometer survey that also addressed the distribution of hard and soft material. Holes were drilled to a depth of 40 ft and logged using both geologic examination and down-hole geophysical surveying. The data identify a large complex of very coarse-grained sediment (clasts up to 8 mm) with interbedded finer-grained sands, silts and clays, underlying a fairly uniform layer of silty clay 6 to 12 ft thick. Geophysical densities of the course-grained materials exceed 2.0 g/cm{sup 2}, and this petrophysical value appears to be a valid discriminator of hard vs. soft sediments in the subsurface. Thirty-four holes, including both core and rotary drilling, were drilled on a portion of the much larger Antelope Lake. A set of pre-drilling geophysical surveys, including time-domain electromagnetic methods, galvanic resistivity soundings, and terrain-conductivity surveying, was used to identify the gross distribution of conductive and resistive facies with respect to the present lake outline. Conductive areas were postulated to represent softer, clay-rich sediments with larger amounts of contained conductive ground water. Initial drilling, consisting of cored drill holes to 100-ft (33-m) depth, confirmed both the specific surface geophysical measurements and the more general ...
Date: December 1, 2004
Creator: Rautman, Christopher Arthur
Partner: UNT Libraries Government Documents Department

Borehole Summary Report for C4997 Rotary Drilling, WTP Seismic Boreholes Project, CY 2006

Description: The following Final Geologic Borehole Report briefly describes the drilling of a single borehole at the Waste Treatment Plant (WTP) on the Hanford, Washington, U.S. Department of Energy (DOE) reservation. The location of the WTP is illustrated in Figure 1-1. The borehole was designated as “C4997”, and was drilled to obtain seismic and lithologic data for the Pretreatment Facility and High-Level Waste Vitrification Plant in the WTP. Borehole C4997 was drilled and logged to a total depth of 1428 ft below ground surface (bgs) on October 8, 2006, and was located approximately 150 ft from a recently cored borehole, designated as “C4998”. Pacific Northwest National Laboratory (PNNL) determined the locations for C4997, C4998, and other boreholes at the WTP in cooperation with the U.S. Army Corps of Engineers (USACE) Review Panel, and the Defense Nuclear Facilities Safety Board (DNFSB). The total depth of Borehole C4997 was also determined by PNNL.
Date: February 28, 2007
Creator: Difebbo, Thomas J.
Partner: UNT Libraries Government Documents Department

Thermal gradients and heat flow data in Colorado and Wyoming: a preliminary report

Description: Temperature gradient data and heat flow data are compiled for 23 core and rotary drill holes in the Rocky Mountains of Colorado and Wyoming. Gradients range from 10.7/sup 0/C/km in the Medicine Bow Mountains, Wyoming, to 40.1/sup 0/C/km in the San Juan Mountains, Colorado. Uncorrected heat flow ranges from 1.1 to HFU at Rawlins, Wyoming to 6.1 at Rico, Colorado.
Date: August 1, 1979
Creator: Decker, E.R. & Bucher, G.J.
Partner: UNT Libraries Government Documents Department

Report of the workshop on advanced geothermal drilling and completion systems

Description: The discussions, conclusions, and recommendations of the Workshop on Advanced Geothermal Drilling and Completion Systems are summarized. The purpose of the workshop was to identify new drilling and completion systems that have the potential for significantly reducing the cost of geothermal wells, and to provide recommendations as to the research and development tasks that are required to develop these advanced systems. Participants in the workshop included representatives from private industry, universities, and government who were organized into four working groups as follows: Rock Drilling Technology, Surface Technology, Borehole Technology, and Directional Drilling Technology. The Panel on Rock Drilling Technology was charged with identifying advanced concepts for breaking rock that could result in instantaneous penetration rates three to five times higher than those of conventional rotary drilling. The Panel on Surface Technology discussed improvements in surface equipment and operating procedures that could contribute to reduced well costs. The Panel on Borehole Technology discussed problems associated with establishing and maintaining a stable borehole for the long-term production of geothermal wells. The Panel on Directional Drilling Technology addressed problems encountered in drilling deviated wells in geothermal reservoirs.
Date: June 1, 1979
Creator: Varnado, S.G. (ed.)
Partner: UNT Libraries Government Documents Department

Investigation of the feasibility of deep microborehole drilling

Description: Recent advances in sensor technology, microelectronics, and telemetry technology make it feasible to produce miniature wellbore logging tools and instrumentation. Microboreholes are proposed for subterranean telemetry installations, exploration, reservoir definition, and reservoir monitoring this assumes that very small diameter bores can be produced for significantly lower cost using very small rigs. A microborehole production concept based on small diameter hydraulic or pneumatic powered mechanical drilling, assemblies deployed on coiled tubing is introduced. The concept is evaluated using, basic mechanics and hydraulics, published theories on rock drilling, and commercial simulations. Small commercial drill bits and hydraulic motors were selected for laboratory scale demonstrations. The feasibility of drilling deep, directional, one to two-inch diameter microboreholes has not been challenged by the results to date. Shallow field testing of prototype systems is needed to continue the feasibility investigation.
Date: January 1, 1997
Creator: Dreesen, D.S. & Cohen, J.H.
Partner: UNT Libraries Government Documents Department

Sandia/DOE geothermal drilling and completion technology development program

Description: The high cost of drilling and completing geothermal wells is an impediment to the development of geothermal energy resources. Technological deficiencies in rotary drilling techniques are evidenced when drilling geothermal wells. The Division of Geothermal Energy (DGE) of the US Department of Energy (DOE) has initiated a program aimed at developing new drilling and completion techniques for geothermal wells. The goals of this program are to reduce well costs 25% by 1982 and 50% by 1986. Sandia Laboratories has managed this technology development program since October 1977, and this paper presents an overview of the program. A statement of program goals and structure is given. The content of the FY-79 program is presented and recent results of R and D projects are given. Plans for development of an advanced drilling and completion system are discussed.
Date: January 1, 1979
Creator: Barnette, J.H.
Partner: UNT Libraries Government Documents Department