Big Island

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Hawai‘i Groundwater and Geothermal Resources Center
https://www.higp.hawaii.edu/hggrc/

Collection Manager: Nicole Lautze
Digitization Coordinator: Alice Kim
Digitization Assistants: Honour Booth and David Perreira

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Now showing 1 - 5 of 34
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    Geophysical survey for ground water evaluation, TMK 8-7-14:02, Island of Hawaii
    (Blackhawk Geosciences, Inc., 1990-05-21) Nance, Tom
    This report contains the results ot time domain electromagnetic (TDEM) measurements acquired on April 27, 1990, on property owned by Cal-Pacific International, Inc. (TMK 8-7-14:02) on the Island of Hawaii. The data was acquired by Blackhawk Geosciences, Inc. at two locations. The specifications of the EM-37 and a brief technical note describing the basic theory of TDEM are given in Appendix A. In the schematic hydrogeologic section often encountered in volcanic islands, ground water is shown in two main occurrences: (1) In the basal mode the fresh water lies in static equilibrium on top of the basal saline water. In this case the Ghyben-Herzberg relationship states that for every foot that the fresh water is elevated above sea level, there will be 40 ft of fresh water below sea level. (2) Typically, further inland, ground water occurrences are often controlled by geologic structures such as dikes or other intrusives. In these cases ground water heads and production can be quite variable. On the property owned by Cal-Pacific International, Inc. the main ground water occurrence is expected to be in the basal mode. For basal mode water exploration, geophysical methods which measure the electrical resistivity of the subsurface are very effective. The reason for this is that electrical resistivity is directly influenced by changes in ground water salinity. By measuring the depth to saline water an estimate of the fresh water resource can be made (i.e., approximately the volume between sea level and the elevation of the saline water). The TDEM method was selected for this survey because it has the best sensitivity to lateral and vertical changes in resistivity compared to other geophysical methods.
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    Time domain electromagnetic surveys for assisting in determining the groundwater resources on property located in the South Kona district, below Kealakekua, Hawaii
    (Blackhawk Geosciences, Inc., 2014-10) Nance, Tom
    "This report contains the procedures and results of a surface Time Domain Electromagnetic (TDEM) geophysical survey performed for groundwater resource evaluation on property located in the South Kona District west of the town of Kealakekua, Hawaii. The project site included property located between the Mamalahoa Bypass Road and the Clarence Lum Won Park. Zapata Incorporated (ZAPATA) performed the survey for 1250 Oceanside, LLC (OSLLC) and Tom Nance Water Resource Engineering (TNWRE) on October 14 and 15, 2014. The main objective of the TDEM survey was to determine if basal or high-level groundwater underlies a proposed well site on the property. The survey was conducted at one TDEM sounding site to help determine the location for a future groundwater well. TDEM is a geophysical method that determines from TDEM is a geophysical method that determines from the surface the geoelectric section (resistivity layering) of the subsurface. From the geoelectric section, information about geology and water quality can be inferred. This is possible because the electrical resistivity of the earth depends on lithology, porosity, degree of saturation, and concentration of dissolved solids in the groundwater. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for water well placement and well completion depths."
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    Geophysical surveys for ground water evaluation near Waikoloa, South Kohala, Hawaii
    (Blackhawk Geosciences, Inc., 1990-02-15) Nance, Tom
    The objectives for the geophysical survey can be understood from the hydrogeologic cross-section, typical of a volcanic island. The volcanic rocks are generally highly permeable and rainfall rapidly infiltrates into the ground and migrates downward to the water table, and eventually discharges into the ocean. Fresh water in these settings is found in two environments. 1. Dike confined waters. Above the rift zone intrusive dikes originating from a magma source below can form ground water dams, and behind these natural dams significant quantities of ground water can be stored. 2.Basal fresh water. The high permeability of the volcanic rocks allows sea water to enter freely under the island, and a delicate balance is reached where a lens of fresh water floats on sea water. The Ghyben-Herzberg relation states that for every foot of fresh water head above sea level there will be 40 ft of fresh water below sea level. The basal water resource was the focus in the investigations for MLR. The drilling depth to the basal fresh water lens rapidly increases with elevation, and the objective of geophysical surveys is to determine the drilling depth to fresh water-and the thickness of the fresh water lens. The impetus for using geophysics is that the cost of a geophysical station is about one-five-hundredth of the cost of drilling a well at elevations above 1,000 ft. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for well placement and well completion depths. The geophysical method employed was time domain electromagnetic (TDEM) soundings. This method was selected because it has proven effective in prior surveys in similar settings in Hawaii.
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    Time domain electromagnetic surveys for assisting in determining the groundwater resources on Waikoloa Land Company property, north well field, Island of Hawaii
    (Blackhawk Geosciences, Inc., 2007-02) Nance, Tom
    "This report contains the procedures and results of surface Time Domain Electromagnetic (TDEM) geophysical surveys performed for groundwater resource evaluation at the North Well Field on Waikoloa Land Company property located on the Island of Hawaii. ZAPATA ENGINEERING Blackhawk Division (Blackhawk) conducted the surveys from January 23 through January 26, 2007 for Tom Nance Water Resource Engineering (TNWRE) of Honolulu, Hawaii and Waikoloa Land Company (WLC) of Waikoloa, Hawaii. The main objective of the TDEM surveys was to explore for additional basal groundwater occurrences at the North Well Field site. The surveys were conducted at six TDEM sites to help determine the optimum location for future groundwater wells located above Waikoloa Village. TDEM is a geophysical method that determines from TDEM is a geophysical method that determines from the surface the geoelectric section (resistivity layering) of the subsurface. From the geoelectric section, information about geology and water quality can be inferred. This is possible because the electrical resistivity of the earth depends on lithology, porosity, degree of saturation, and concentration of dissolved solids in the groundwater. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for water well placement and well completion depths."
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    Time domain electromagnetic surveys for assisting in determining the groundwater resources on Queen Liliuokalani Trust property, Island of Hawaii
    (Blackhawk Geosciences, Inc., 2007-03) Nance, Tom
    "This report contains the procedures and results of surface Time Domain Electromagnetic (TDEM) geophysical surveys performed for groundwater resource evaluation on Queen Liliuokalani Trust property located at the Keahuolu Tract on the Island of Hawaii. ZAPATA ENGINEERING Blackhawk Division (Blackhawk) conducted the surveys from January 27 to January 30, 2007 for Tom Nance Water Resource Engineering (TNWRE) of Honolulu, Hawaii and Queen Liliuokalani Trust (QLT) of Honolulu, Hawaii. The main objective of the TDEM surveys was to explore for additional high-level groundwater occurrences in the immediate vicinity of the existing 1.0 MG Water Tank located on QLT property above the Mamalahoa Highway. The surveys were conducted at three additional sites to help determine the optimum location for a future groundwater well located near the QLT Water Tank. TDEM is a geophysical method that determines from TDEM is a geophysical method that determines from the surface the geoelectric section (resistivity layering) of the subsurface. From the geoelectric section, information about geology and water quality can be inferred. This is possible because the electrical resistivity of the earth depends on lithology, porosity, degree of saturation, and concentration of dissolved solids in the groundwater. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for water well placement and well completion depths."