Results for “DRILLING” — Page 89

DOE OSTI2013

Water Management Strategies for Improved Coalbed Methane Production in the Black Warrior Basin

The modern coalbed methane industry was born in the Black Warrior Basin of Alabama and has to date produced more than 2.6 trillion cubic feet of gas and 1.6 billion barrels of water. The coalbed gas industry in this area is dependent on instream disposal of co-produced water, which ranges from nearly potable sodium-bicarbonate water to hypersaline sodium-chloride water. This study employed diverse analytical methods to characterize water chemistry in light of the regional geologic framework and to evaluate the full range of water management options for the Black Warrior coalbed methane industry. Results reveal strong interrelationships among regional geology, water chemistry, and gas chemistry. Coalbed methane is produced from multiple coal seams in Pennsylvanian-age strata of the Pottsville Coal Interval, in which water chemistry is influenced by a structurally controlled meteoric recharge area along the southeastern margin of the basin. The most important constituents of concern in the produced water include chlorides, ammonia compounds, and organic substances. Regional mapping and statistical analysis indicate that the concentrations of most ionic compounds, metallic substances, and nonmetallic substances correlate with total dissolved solids and chlorides. Gas is effectively produced at pipeline quality, and the only significant impurity is N{sub 2}. Geochemical analysis indicates that the gas is of mixed thermogenic-biogenic origin. Stable isotopic analysis of produced gas and calcite vein fills indicates that widespread late-stage microbial methanogenesis occurred primarily along a CO{sub 2} reduction metabolic pathway. Organic compounds in the produced water appear to have helped sustain microbial communities. Ammonia and ammonium levels increase with total dissolved solids content and appear to have played a role in late-stage microbial methanogenesis and the generation of N{sub 2}. Gas production tends to decline exponentially, whereas water production tends to decline hyperbolically. Hyperbolic decline indicates that water volume is of greatest concern early in the life of a coalbed methane project. Regional mapping indicates that gas production is controlled primarily by the ability to depressurize permeable coal seams that are natively within the steep part of the adsorption isotherm. Water production is greatest within the freshwater intrusion and below thick Cretaceous cover strata and is least in areas of underpressure. Water management strategies include instream disposal, which can be applied effectively in most parts of the basin. Deep disposal may be applicable locally, particularly where high salinity limits the ability to dispose into streams. Artificial wetlands show promise for the management of saline water, especially where the reservoir yield is limited. Beneficial use options include municipal water supply, agricultural use, and industrial use. The water may be of use to an inland shrimp farming industry, which is active around the southwestern coalbed methane fields. The best opportunities for beneficial use are reuse of water by the coalbed methane industry for drilling and hydraulic fracturing. This research has further highlighted opportunities for additional research on treatment efficiency, the origin of nitrogen compounds, organic geochemistry, biogenic gas generation, flow modeling, and computer simulation. Results of this study are being disseminated through a vigorous technology transfer program that includes web resources, numerous presentations to stakeholders, and a variety of technical publications.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2013

Assessment of Factors Influencing Effective CO 2 Storage Capacity and Injectivity in Eastern Gas Shales

Building upon advances in technology, production of natural gas from organic-rich shales is rapidly developing as a major hydrocarbon supply option in North America and around the world. The same technology advances that have facilitated this revolution - dense well spacing, horizontal drilling, and hydraulic fracturing - may help to facilitate enhanced gas recovery (EGR) and carbon dioxide (CO 2 ) storage in these formations. The potential storage of CO 2 in shales is attracting increasing interest, especially in Appalachian Basin states that have extensive shale deposits, but limited CO 2 storage capacity in conventional reservoirs. The goal of this cooperative research project was to build upon previous and on-going work to assess key factors that could influence effective EGR, CO 2 storage capacity, and injectivity in selected Eastern gas shales, including the Devonian Marcellus Shale, the Devonian Ohio Shale, the Ordovician Utica and Point Pleasant shale and equivalent formations, and the late Devonian-age Antrim Shale. The project had the following objectives: (1) Analyze and synthesize geologic information and reservoir data through collaboration with selected State geological surveys, universities, and oil and gas operators; (2) improve reservoir models to perform reservoir simulations to better understand the shale characteristics that impact EGR, storage capacity and CO 2 injectivity in the targeted shales; (3) Analyze results of a targeted, highly monitored, small-scale CO 2 injection test and incorporate into ongoing characterization and simulation work; (4) Test and model a smart particle early warning concept that can potentially be used to inject water with uniquely labeled particles before the start of CO 2 injection; (5) Identify and evaluate potential constraints to economic CO 2 storage in gas shales, and propose development approaches that overcome these constraints; and (6) Complete new basin-level characterizations for the CO 2 storage capacity and injectivity potential of the targeted eastern shales. In total, these Eastern gas shales cover an area of over 116 million acres, may contain an estimated 6,000 trillion cubic feet (Tcf) of gas in place, and have a maximum theoretical storage capacity of over 600 million metric tons. Not all of this gas in-place will be recoverable, and economics will further limit how much will be economic to produce using EGR techniques with CO 2 injection. Reservoir models were developed and simulations were conducted to characterize the potential for both CO 2 storage and EGR for the target gas shale formations. Based on that, engineering costing and cash flow analyses were used to estimate economic potential based on future natural gas prices and possible financial incentives. The objective was to assume that EGR and CO 2 storage activities would commence consistent with the historical development practices. Alternative CO 2 injection/EGR scenarios were considered and compared to well production without CO 2 injection. These simulations were conducted for specific, defined model areas in each shale gas play. The resulting outputs were estimated recovery per typical well (per 80 acres), and the estimated CO 2 that would be injected and remain in the reservoir (i.e., not produced), and thus ultimately assumed to be stored. The application of this approach aggregated to the entire area of the four shale gas plays concluded that they contain nearly 1,300 Tcf of both primary production and EGR potential, of which an estimated 460 Tcf could be economic to produce with reasonable gas prices and/or modest incentives. This could facilitate the storage of nearly 50 Gt of CO 2 in the Marcellus, Utica, Antrim, and Devonian Ohio shales.

03 NATURAL GAS↗

DOE OSTI2014

Risk Evaluation for CO 2 Geosequestration in the Knox Supergroup, Illinois Basin (Final Report)

This report describes a process and provides seed information for identifying and evaluating risks pertinent to a hypothetical carbon dioxide (CO 2 ) capture and sequestration (CCS) project. In the envisioned project, the target sequestration reservoir rock is the Potosi Formation of the Knox Supergroup. The Potosi is identified as a potential target formation because (1) at least locally, it contains vuggy to cavernous layers that have very high porosity, and (2) it is present in areas where the deeper Mt. Simon Sandstone (a known potential reservoir unit) is absent or nonporous. The key report content is discussed in Section 3.3, which describes two lists of Features, Events, and Processes (FEPs) that should be considered during the design stage of such a project. These lists primarily highlight risk elements particular to the establishment of the Potosi as the target formation in general. The lists are consciously incomplete with respect to risk elements that would be relevant for essentially all CCS projects regardless of location or geology. In addition, other risk elements specific to a particular future project site would have to be identified. Sources for the FEPs and scenarios listed here include the iconic Quintessa FEPs list developed for the International Energy Agency Greenhouse Gas (IEAGHG) Programme; previous risk evaluation projects executed by Schlumberger Carbon Services; and new input solicited from experts currently working on aspects of CCS in the Knox geology. The projects used as sources of risk information are primarily those that have targeted carbonate reservoir rocks similar in age, stratigraphy, and mineralogy to the Knox-Potosi. Risks of using the Potosi Formation as the target sequestration reservoir for a CCS project include uncertainties about the levels of porosity and permeability of that rock unit; the lateral consistency and continuity of those properties; and the ability of the project team to identify suitable (i.e., persistently porous and permeable) injection depths within the overall formation. Less direct implications include the vertical position of the Potosi within the rock column and the absence of a laterally extensive shale caprock immediately overlying the Potosi. Based on modeling work done partly in association with this risk report, risks that should also be evaluated include the ability of available methods to predict and track the development of a CO 2 plume as it migrates away from the injection point(s). The geologic and hydrodynamic uncertainties present risks that are compounded at the stage of acquiring necessary drilling and injection permits. It is anticipated that, in the future, a regional geologic study or CO 2 -emitter request may identify a small specific area as a prospective CCS project site. At that point, the FEPs lists provided in this report should be evaluated by experts for their relative levels of risk. A procedure for this evaluation is provided. The higher-risk FEPs should then be used to write project-specific scenarios that may themselves be evaluated for risk. Then, actions to reduce and to manage risk can be described and undertaken. The FEPs lists provided as Appendix 2 should not be considered complete, as potentially the most important risks are ones that have not yet been thought of. But these lists are intended to include the most important risk elements pertinent to a Potosi-target CCS project, and they provide a good starting point for diligent risk identification, evaluation, and management.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2013

Deepwater and Ultra-Deepwater Research: Annual FY13 Format

In FY13 offshore energy resources research conducted by the National Energy Technology Laboratory (NETL) Office of Research and Development (ORD) focused on developing a scientific base for predicting and quantifying potential risks associated with exploration and production in extreme offshore systems. Specifically, the Deepwater and Ultra-Deepwater Research (UDW) portfolio is focused on reducing and mitigating deleterious environmental events associated with deepwater and ultra-deepwater offshore drilling and production.

03 NATURAL GAS↗

DOE OSTI2013

"Development and Commercialization of Alternative Carbon Precursors and Conversion Technologies" (CRADA Final Report)

The overall objective of the collaborative research performed by the Oak Ridge National Laboratory (ORNL) and the Dow Chemical Company under this Cooperative Research And Development Agreement (CRADA NFE-10-02991) was to develop and establish pathways to commercialize new carbon fiber precursor and conversion technology. This technology is to produce alternative polymer fiber precursor formulations as well as scaled energy-efficient advanced conversion technology to enable continuous mode conversion to obtain carbonized fibers that are technically and economically viable in industrial markets such as transportation, wind energy, infrastructure and oil drilling applications. There have been efforts in the past to produce a low cost carbon fiber. These attempts have to be interpreted against the backdrop of the market needs at the time, which were strictly military aircraft and high-end aerospace components. In fact, manufacturing costs have been reduced from those days to current practice, where both process optimization and volume production have enabled carbon fiber to become available at prices below $20/lb. However, the requirements of the lucrative aerospace market limits further price reductions from current practice. This approach is different because specific industrial applications are targeted, most specifically wind turbine blade and light vehicle transportation, where aircraft grade carbon fiber is not required. As a result, researchers are free to adjust both manufacturing process and precursor chemistry to meet the relaxed physical specifications at a lower cost. This report documents the approach and findings of this cooperative research in alternative precursors and advanced conversion for production of cost-effective carbon fiber for energy missions. Due to export control, proprietary restrictions, and CRADA protected data considerations, specific design details and processing parameters are not included in this report.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2014

Letter Report Documenting Progress of Second Generation ATF FeCrAl Alloy Fabrication

Development of the 2 nd generation ATF FeCrAl alloy has been initiated, and a candidate alloy was selected for trial tube fabrication through hot-extrusion and gun-drilling processes. Four alloys based on Fe-13Cr-4.5Al-0.15Y in weight percent were newly cast with minor alloying additions of Mo, Si, Nb, and C to promote solid-solution and second-phase precipitate strengthening. The alloy compositions were selected with guidance from computational thermodynamic tools. The lab-scale heats of ~ 600g were arc-melted and drop-cast, homogenized, hot-forged and -rolled, and then annealed producing plate shape samples. An alloy with Mo and Nb additions (C35MN) processed at 800°C exhibits very fine sub-grain structure with the sub-grain size of 1-3μm which exhibited more than 25% better yield and tensile strengths together with decent ductility compared to the other FeCrAl alloys at room temperature. It was found that the Nb addition was key to improving thermal stability of the fine sub-grain structure. Optimally, grains of less than 30 microns are desired, with grains up to and order of magnitude in desired produced through Nb addition. Scale-up effort of the C35MN alloy was made in collaboration with a commercial cast company who has a capability of vacuum induction melting. A 39lb columnar ingot with ~81mm diameter and ~305mm height (with hot-top) was commercially cast, homogenized, hot-extruded, and annealed providing 10mm-diameter bar-shape samples with the fine sub-grain structure. This commercial heat proved consistent with materials produced at ORNL at the lab-scale. Tubes and end caps were machined from the bar sample and provided to another work package for the ATF-1 irradiation campaign in the milestone M3FT-14OR0202251.

2nd generation ATF FeCrAl alloy↗

DOE OSTI2014

Energy-Saving Melting and Revert Reduction Technology (E-SMARRT): Use of Laser Engineered Net Shaping for Rapid Manufacturing of Dies with Protective Coatings and Improved Thermal Management

In the high pressure die casting process, molten metal is introduced into a die cavity at high pressure and velocity, enabling castings of thin wall section and complex geometry to be obtained. Traditional die materials have been hot work die steels, commonly H13. Manufacture of the dies involves machining the desired geometry from monolithic blocks of annealed tool steel, heat treating to desired hardness and toughness, and final machining, grinding and polishing. The die is fabricated with internal water cooling passages created by drilling.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2014

2013 Idaho National Laboratory Water Use Report and Comprehensive Well Inventory (Revision 22)

This 2013 Idaho National Laboratory Water Use Report and Comprehensive Well Inventory (Revision 22) provides water use information for production and potable water wells at the Idaho National Laboratory for Calendar Year 2013. It also provides detailed information for new, modified, and decommissioned wells and holes. Two new wells were drilled and completed in Calendar Year 2013. No modifications were performed on any wells. Seven wells were decommissioned in Calendar Year 2013. Detailed construction information for the new and decommissioned wells is provided. Location maps are included, provided survey information was available. This report is being submitted in accordance with the Water Rights Agreement between the State of Idaho and the United States, for the United States Department of Energy (dated 1990) and the subsequent Partial Decree for Water Right 34-10901 issued June 20, 2003.

2013 idaho national laboratory water use report an↗

DOE OSTI2014

Improved Mobility Control for Carbon Dioxide (CO{sub 2}) Enhanced Oil Recovery Using Silica-Polymer-Initiator (SPI) Gels

SPI gels are multi-component silicate based gels for improving (areal and vertical) conformance in oilfield enhanced recovery operations, including water-floods and carbon dioxide (CO{sub 2}) floods, as well as other applications. SPI mixtures are like-water when pumped, but form light up to very thick, paste-like gels in contact with CO{sub 2}. When formed they are 3 to 10 times stronger than any gelled polyacrylamide gel now available, however, they are not as strong as cement or epoxy, allowing them to be washed / jetted out of the wellbore without drilling. This DOE funded project allowed 8 SPI field treatments to be performed in 6 wells (5 injection wells and 1 production well) in 2 different fields with different operators, in 2 different basins (Gulf Coast and Permian) and in 2 different rock types (sandstone and dolomite). Field A was in a central Mississippi sandstone that injected CO{sub 2} as an immiscible process. Field B was in the west Texas San Andres dolomite formation with a mature water-alternating-gas miscible CO{sub 2} flood. Field A treatments are now over 1 year old while Field B treatments have only 4 months data available under variable WAG conditions. Both fields had other operational events and well work occurring before/ during / after the treatments making definitive evaluation difficult. Laboratory static beaker and dynamic sand pack tests were performed with Ottawa sand and both fields’ core material, brines and crude oils to improve SPI chemistry, optimize SPI formulations, ensure SPI mix compatibility with field rocks and fluids, optimize SPI treatment field treatment volumes and methods, and ensure that strong gels set in the reservoir. Field quality control procedures were designed and utilized. Pre-treatment well (surface) injectivities ranged from 0.39 to 7.9 MMCF/psi. The SPI treatment volumes ranged from 20.7 cubic meters (m{sup 3}, 5460 gallons/ 130 bbls) to 691 m{sup 3} (182,658 gallons/ 4349 bbls). Various size and types of chemical/ water buffers before and after the SPI mix ensured that pre-gelled SPI mix got out into the formation before setting into a gel. SPI gels were found to be 3 to 10 times stronger than any commercially available cross-linked polyacrylamide gels based on Penetrometer and Bulk Gel Shear Testing. Because of SPI’s unique chemistry with CO{sub 2}, both laboratory and later field tests demonstrated that multiple, smaller volume SPI treatments maybe more effective than one single large SPI treatment. CO{sub 2} injectivities in injection well in both fields were reduced by 33 to 70% indicating that injected CO{sub 2} is now going into new zones. This reduction has lasted 1+ year in Field A. Oil production increased and CO{sub 2} production decreased in 5 Field A production wells, offsets to Well #1 injector, for a total of about 2,250 m{sup 3} (600,000 gallons/ 14,250 bbls) of incremental oil production- a $140 / SPI bbl return. Treated marginal production well, Field A Well #2, immediately began showing increased oil production totaling 238 m{sup 3} (63,000 gallons/ 1500 BBLs) over 1 year and an immediate 81% reduced gas-oil ratio.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2013

A Ten Step Protocol and Plan for CCS Site Characterization, Based on an Analysis of the Rocky Mountain Region, USA

This report expresses a Ten-Step Protocol for CO2 Storage Site Characterization, the final outcome of an extensive Site Characterization analysis of the Rocky Mountain region, USA. These ten steps include: (1) regional assessment and data gathering; (2) identification and analysis of appropriate local sites for characterization; (3) public engagement; (4) geologic and geophysical analysis of local site(s); (5) stratigraphic well drilling and coring; (6) core analysis and interpretation with other data; (7) database assembly and static model development; (8) storage capacity assessment; (9) simulation and uncertainty assessment; (10) risk assessment. While the results detailed here are primarily germane to the Rocky Mountain region, the intent of this protocol is to be portable or generally applicable for CO2 storage site characterization.

McPherson, Brian↗

DOE OSTI2013

Interdisciplinary Investigation of CO2 Sequestration in Depleted Shale Gas Formations

This project investigates the feasibility of geologic sequestration of CO2 in depleted shale gas reservoirs from an interdisciplinary viewpoint. It is anticipated that over the next two decades, tens of thousands of wells will be drilled in the 23 states in which organic-rich shale gas deposits are found. This research investigates the feasibility of using these formations for sequestration. If feasible, the number of sites where CO2 can be sequestered increases dramatically. The research embraces a broad array of length scales ranging from the ~10 nanometer scale of the pores in the shale formations to reservoir scale through a series of integrated laboratory and theoretical studies.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2014

ER Operations Installation of Three FLUTe Soil-Vapor Monitoring Wells (MWL-SV03 MWL-SV04 and MWL-SV05) at the Mixed Waste Landfill.

This installation report describes the May through July 2014 drilling activities performed for the installation of three multi-port soil-vapor monitoring wells (MWL-SV03, MWL-SV04, and MWL-SV05) at the Mixed Waste Landfill (MWL), which is located at Sandia National Laboratories, New Mexico (SNL/NM). SNL/NM is managed and operated by Sandia Corporation (Sandia), a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy (DOE)/National Nuclear Security Administration. The MWL is designated as Solid Waste Management Unit (SWMU) 76 and is located in Technical Area (TA) III (Figure 1-1). The locations of the three soil-vapor monitoring wells (MWL-SV03, MWL-SV04, and MWL-SV05) are shown in Figure 1-2

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2014

Evaluation of the Performance of O-rings Made with Different Elastomeric Polymers in Simulated Geothermal Environments at 300°C

This paper aims to evaluate the survival of O-rings made with six different elastomeric polymers, EPDM, type I- and II-FKM, FEPM, FFKM, and FSR, in five different simulated geothermal environments at 300°C. It further defines the relative strengths and weaknesses of the materials in each environment. The environments tested were: 1) non-aerated steam-cooling cycles, 2) aerated steam-cooling cycles, 3) water-based drilling fluid, 4) CO2-rich geo-brine fluid, and, 5) heat-cool water quenching cycles. Following exposure, the extent of oxidation, oxidationinduced degradation, thermal behaviors, micro-defects, permeation depths of ionic species present in environments throughout the O-ring, silicate-related scale-deposition, and changes in mechanical properties were assessed.

36 MATERIALS SCIENCE↗

DOE OSTI2014

A Historical Evaluation of the U15 Complex, Nevada National Security Site, Nye County, Nevada

This report presents a historical evaluation of the U15 Complex on the Nevada National Security Site (NNSS) in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office and the U.S. Department of Defense, Defense Threat Reduction Agency. Three underground nuclear tests and two underground nuclear fuel storage experiments were conducted at the complex. The nuclear tests were Hard Hat in 1962, Tiny Tot in 1965, and Pile Driver in 1966. The Hard Hat and Pile Driver nuclear tests involved different types of experiment sections in test drifts at various distances from the explosion in order to determine which sections could best survive in order to design underground command centers. The Tiny Tot nuclear test involved an underground cavity in which the nuclear test was executed. It also provided data in designing underground structures and facilities to withstand a nuclear attack. The underground nuclear fuel storage experiments were Heater Test 1 from 1977 to 1978 and Spent Fuel Test - Climax from 1978 to 1985. Heater Test 1 was used to design the later Spent Fuel Test - Climax experiment. The latter experiment was a model of a larger underground storage facility and primarily involved recording the conditions of the spent fuel and the surrounding granite medium. Fieldwork was performed intermittently in the summers of 2011 and 2013, totaling 17 days. Access to the underground tunnel complex is sealed and unavailable. Restricted to the surface, four buildings, four structures, and 92 features associated with nuclear testing and fuel storage experiment activities at the U15 Complex have been recorded. Most of these are along the west side of the complex and next to the primary access road and are characteristic of an industrial mining site, albeit one with scientific interests. The geomorphological fieldwork was conducted over three days in the summer of 2011. It was discovered that major modifications to the terrain have resulted from four principal activities. These are road construction and maintenance, mining activities related to development of the tunnel complex, site preparation for activities related to the tests and experiments, and construction of drill pads and retention ponds. Six large trenches for exploring across the Boundary geologic fault are also present. The U15 Complex, designated historic district 143 and site 26NY15177, is eligible to the National Register of Historic Places under Criteria A, C, and D of 36 CFR Part 60.4. As a historic district and archaeological site eligible to the National Register of Historic Places, the Desert Research Institute recommends that the area defined for the U15 Complex, historic district 143 and site 26NY15117, be left in place in its current condition. The U15 Complex should also be included in the NNSS cultural resources monitoring program and monitored for disturbances or alterations.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2014

A Historical Evaluation of the U15 Complex, Nevada National Security Site, Nye County, Nevada

This report presents a historical evaluation of the U15 Complex on the Nevada National Security Site (NNSS) in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office and the U.S. Department of Defense, Defense Threat Reduction Agency. Three underground nuclear tests and two underground nuclear fuel storage experiments were conducted at the complex. The nuclear tests were Hard Hat in 1962, Tiny Tot in 1965, and Pile Driver in 1966. The Hard Hat and Pile Driver nuclear tests involved different types of experiment sections in test drifts at various distances from the explosion in order to determine which sections could best survive in order to design underground command centers. The Tiny Tot nuclear test involved an underground cavity in which the nuclear test was executed. It also provided data in designing underground structures and facilities to withstand a nuclear attack. The underground nuclear fuel storage experiments were Heater Test 1 from 1977 to 1978 and Spent Fuel Test - Climax from 1978 to 1985. Heater Test 1 was used to design the later Spent Fuel Test - Climax experiment. The latter experiment was a model of a larger underground storage facility and primarily involved recording the conditions of the spent fuel and the surrounding granite medium. Fieldwork was performed intermittently in the summers of 2011 and 2013, totaling 17 days. Access to the underground tunnel complex is sealed and unavailable. Restricted to the surface, four buildings, four structures, and 92 features associated with nuclear testing and fuel storage experiment activities at the U15 Complex have been recorded. Most of these are along the west side of the complex and next to the primary access road and are characteristic of an industrial mining site, albeit one with scientific interests. The geomorphological fieldwork was conducted over three days in the summer of 2011. It was discovered that major modifications to the terrain have resulted from four principal activities. These are road construction and maintenance, mining activities related to development of the tunnel complex, site preparation for activities related to the tests and experiments, and construction of drill pads and retention ponds. Six large trenches for exploring across the Boundary geologic fault are also present. The U15 Complex, designated historic district 143 and site 26NY15177, is eligible to the National Register of Historic Places under Criteria A, C, and D of 36 CFR Part 60.4. As a historic district and archaeological site eligible to the National Register of Historic Places, the Desert Research Institute recommends that the area defined for the U15 Complex, historic district 143 and site 26NY15117, be left in place in its current condition. The U15 Complex should also be included in the NNSS cultural resources monitoring program and monitored for disturbances or alterations.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2014

A Historical Evaluation of the U15 Complex, Nevada National Security Site, Nye County, Nevada

This report presents a historical evaluation of the U15 Complex on the Nevada National Security Site (NNSS) in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office and the U.S. Department of Defense, Defense Threat Reduction Agency. Three underground nuclear tests and two underground nuclear fuel storage experiments were conducted at the complex. The nuclear tests were Hard Hat in 1962, Tiny Tot in 1965, and Pile Driver in 1966. The Hard Hat and Pile Driver nuclear tests involved different types of experiment sections in test drifts at various distances from the explosion in order to determine which sections could best survive in order to design underground command centers. The Tiny Tot nuclear test involved an underground cavity in which the nuclear test was executed. It also provided data in designing underground structures and facilities to withstand a nuclear attack. The underground nuclear fuel storage experiments were Heater Test 1 from 1977 to 1978 and Spent Fuel Test - Climax from 1978 to 1985. Heater Test 1 was used to design the later Spent Fuel Test - Climax experiment. The latter experiment was a model of a larger underground storage facility and primarily involved recording the conditions of the spent fuel and the surrounding granite medium. Fieldwork was performed intermittently in the summers of 2011 and 2013, totaling 17 days. Access to the underground tunnel complex is sealed and unavailable. Restricted to the surface, four buildings, four structures, and 92 features associated with nuclear testing and fuel storage experiment activities at the U15 Complex have been recorded. Most of these are along the west side of the complex and next to the primary access road and are characteristic of an industrial mining site, albeit one with scientific interests. The geomorphological fieldwork was conducted over three days in the summer of 2011. It was discovered that major modifications to the terrain have resulted from four principal activities. These are road construction and maintenance, mining activities related to development of the tunnel complex, site preparation for activities related to the tests and experiments, and construction of drill pads and retention ponds. Six large trenches for exploring across the Boundary geologic fault are also present. The U15 Complex, designated historic district 143 and site 26NY15177, is eligible to the National Register of Historic Places under Criteria A, C, and D of 36 CFR Part 60.4. As a historic district and archaeological site eligible to the National Register of Historic Places, the Desert Research Institute recommends that the area defined for the U15 Complex, historic district 143 and site 26NY15117, be left in place in its current condition. The U15 Complex should also be included in the NNSS cultural resources monitoring program and monitored for disturbances or alterations.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2014

A Historical Evaluation of the U15 Complex, Nevada National Security Site, Nye County, Nevada

This report presents a historical evaluation of the U15 Complex on the Nevada National Security Site (NNSS) in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office and the U.S. Department of Defense, Defense Threat Reduction Agency. Three underground nuclear tests and two underground nuclear fuel storage experiments were conducted at the complex. The nuclear tests were Hard Hat in 1962, Tiny Tot in 1965, and Pile Driver in 1966. The Hard Hat and Pile Driver nuclear tests involved different types of experiment sections in test drifts at various distances from the explosion in order to determine which sections could best survive in order to design underground command centers. The Tiny Tot nuclear test involved an underground cavity in which the nuclear test was executed. It also provided data in designing underground structures and facilities to withstand a nuclear attack. The underground nuclear fuel storage experiments were Heater Test 1 from 1977 to 1978 and Spent Fuel Test - Climax from 1978 to 1985. Heater Test 1 was used to design the later Spent Fuel Test - Climax experiment. The latter experiment was a model of a larger underground storage facility and primarily involved recording the conditions of the spent fuel and the surrounding granite medium. Fieldwork was performed intermittently in the summers of 2011 and 2013, totaling 17 days. Access to the underground tunnel complex is sealed and unavailable. Restricted to the surface, four buildings, four structures, and 92 features associated with nuclear testing and fuel storage experiment activities at the U15 Complex have been recorded. Most of these are along the west side of the complex and next to the primary access road and are characteristic of an industrial mining site, albeit one with scientific interests. The geomorphological fieldwork was conducted over three days in the summer of 2011. It was discovered that major modifications to the terrain have resulted from four principal activities. These are road construction and maintenance, mining activities related to development of the tunnel complex, site preparation for activities related to the tests and experiments, and construction of drill pads and retention ponds. Six large trenches for exploring across the Boundary geologic fault are also present. The U15 Complex, designated historic district 143 and site 26NY15177, is eligible to the National Register of Historic Places under Criteria A, C, and D of 36 CFR Part 60.4. As a historic district and archaeological site eligible to the National Register of Historic Places, the Desert Research Institute recommends that the area defined for the U15 Complex, historic district 143 and site 26NY15117, be left in place in its current condition. The U15 Complex should also be included in the NNSS cultural resources monitoring program and monitored for disturbances or alterations.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2015

Development of an Advanced Stimulation / Production Predictive Simulator for Enhanced Geothermal Systems

There are several well-known obstacles to the successful deployment of EGS projects on a commercial scale, of course. EGS projects are expected to be deeper, on the average, than conventional “natural” geothermal reservoirs, and drilling costs are already a formidable barrier to conventional geothermal projects. Unlike conventional resources (which frequently announce their presence with natural manifestations such as geysers, hot springs and fumaroles), EGS prospects are likely to appear fairly undistinguished from the earth surface. And, of course, the probable necessity of fabricating a subterranean fluid circulation network to mine the heat from the rock (instead of simply relying on natural, pre-existing permeable fractures) adds a significant degree of uncertainty to the prospects for success. Accordingly, the basic motivation for the work presented herein was to try to develop a new set of tools that would be more suitable for this purpose. Several years ago, the Department of Energy’s Geothermal Technologies Office recognized this need and funded a cost-shared grant to our company (then SAIC, now Leidos) to partner with Geowatt AG of Zurich, Switzerland and undertake the development of a new reservoir simulator that would be more suitable for EGS forecasting than the existing tools. That project has now been completed and a new numerical geothermal reservoir simulator has been developed. It is named “HeatEx” (for “Heat Extraction”) and is almost completely new, although its methodology owes a great deal to other previous geothermal software development efforts, including Geowatt’s “HEX-S” code, the STAR and SPFRAC simulators developed here at SAIC/Leidos, the MINC approach originally developed at LBNL, and tracer analysis software originally formulated at INEL. Furthermore, the development effort was led by engineers with many years of experience in using reservoir simulation software to make meaningful forecasts for real geothermal projects, not just software designers. It is hoped that, as a result, HeatEx will prove useful during the early stages of the development of EGS technology. The basic objective was to design a tool that could use field data that are likely to become available during the early phases of an EGS project (that is, during initial reconnaissance and fracture stimulation operations) to guide forecasts of the longer-term behavior of the system during production and heat-mining.

15 GEOTHERMAL ENERGY↗