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
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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Item type: Item , Geophysical survey for ground water evaluation, TMK 8-7-14:02, Island of Hawaii(Blackhawk Geosciences, Inc., 1990-05-21) Nance, TomThis 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.Item type: Item , 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."Item type: Item , Geophysical surveys for ground water evaluation near Waikoloa, South Kohala, Hawaii(Blackhawk Geosciences, Inc., 1990-02-15) Nance, TomThe 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.Item type: Item , 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."Item type: Item , 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."Item type: Item , Time domain electromagnetic surveys for assisting in determining the groundwater resources on Kealakekua Ranch Ltd. 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 Kealakekua Ranch Ltd. property located on the Kealakekua Tract on the Island of Hawaii. ZAPATA ENGINEERING Blackhawk Division (Blackhawk) conducted the surveys from January 31 to February 3, 2007 for Pa’ahana Enterprises LLC (PEL) of Kealakekua, Hawaii and Kealakekua Ranch, Ltd. (KRL) of Captain Cook, Hawaii. The main objective of the TDEM surveys was to explore for basal and high-level groundwater occurrences located on KRL property above the Kealakekua Ranch Center. The surveys were conducted at four TDEM sites to help determine the optimum location for a future groundwater well above the Mamalahoa Highway in Captain Cook, Hawaii. 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."Item type: Item , Time domain electromagnetic surveys for assisting in determining the groundwater resources on Greenwell Farms 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 Greenwell Farms property located on the Island of Hawaii. ZAPATA ENGINEERING Blackhawk Division (Blackhawk) conducted the surveys on February 2, 2007 for Pa’ahana Enterprises LLC (PEL) of Kealakekua, Hawaii and Greenwell Farms (GF) of Kealakekua, Hawaii. The main objective of the TDEM surveys was to explore for groundwater occurrences located on GF property near the Greenwell Farms Coffee Plantation. The surveys were conducted at two TDEM sites to help determine the optimum location for a future groundwater well below the Mamalahoa Highway in Kealakekua, Hawaii. 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."Item type: Item , Time domain electromagnetic survey for assisting in determining the groundwater resources on property located in the South Kohala District above Kawaihae, Hawaii(Tom Nance Water Resource Engineering, 2011-08) Nance, Tom"This report contains the procedures and results of surface Time Domain Electromagnetic (TDEM) geophysical surveys performed for groundwater resource evaluation on property located in the South Kohala District above the town of Kawaihae, Hawaii. The project site included land located both north and east of the junction of Highway 19 and Kawaihae Road toward the town of Kamuela and along the Kohala Mountain Road toward Hawi. Zapata Incorporated (ZAPATA) performed the surveys for Queen Emma Land Company (QELC) and Tom Nance Water Resource Engineering (TNWRE) from July 20 through July 29, 2011. The main objective of the TDEM surveys was to explore for basal or high-level groundwater on the property. The surveys were conducted at seventeen TDEM sounding sites to help determine the location for future groundwater wells. 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."Item type: Item , Time domain electromagnetic survey for assisting in determining the groundwater resources on property located in the Kau District, Island of Hawaii(Blackhawk Geosciences, Inc., 2008-08) 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 near Kahuku Ranch in the Kau District, Island of Hawaii. Zapata Incorporated, Blackhawk Division (Blackhawk) conducted the survey from August 5 through August 9, 2007 for Nani Kahuku Aina, LLC (NKA) located in Aiea, Hawaii. The main objective of the TDEM survey was to explore for high-level groundwater occurrences on property that NKA has gained access permission. The survey was conducted at five TDEM sites to help determine the optimum location for a future groundwater well located along Mainalahoa Highway (Hwy 11) near the junction of South Point Road. 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, the 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 well placement and well completion depths."Item type: Item , Time domain electromagnetic surveys for assisting in determining the groundwater resources on the Hamakua Coast, Island of Hawaii : preliminary report(Blackhawk Geosciences, Inc., 2004-06-10) Nance, TomThis report contains the results of surface Time Domain Electromagnetic (TDEM) geophysical surveys performed for groundwater resource evaluation along the Hamakua Coast on the Island of Hawaii. Blackhawk GeoServices (Blackhawk) conducted the surveys from April 15 through April 24 and May 1 through May 3, 2004 for Tom Nance Water Resource Engineering (TNWRE) and the Department of Water Supply (DWS), County of Hawaii, Hawaii. 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, the degree of saturation, and concentration of dissolved solids in the ground water. The main objectives of the TDEM surveys on Hawaii were to explore for possible basal and high-level groundwater occurrences at the survey areas. These TDEM surveys were conducted along four (4) mauka-makai transects located near Kukuihaele, Kapulena, Paauhau and Paauilo along the Hamakua Coast. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for well placement and well completion depths.Item type: Item , Time domain electromagnetic surveys near Kukaiau, Hamakua Coast, Island of Hawaii : preliminary report(Blackhawk Geosciences, Inc., 2004-05-14) Nance, Tom"This report contains the results of surface Time Domain Electromagnetic (TDEM) geophysical surveys performed for groundwater resource evaluation along the Hamakua Coast on the Island of Hawaii. Blackhawk GeoServices (Blackhawk) conducted the surveys from April 15 through April 24 and May 1 through May 3, 2004 for Tom Nance Water Resource Engineering (TNWRE) and the Department of Water Supply (DWS), County of Hawaii, Hawaii. 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, because the electrical resistivity of the earth depends on lithology, porosity, the degree of saturation, and concentration of dissolved solids in the ground water. The main objectives of the TDEM surveys on Hawaii were to explore for possible basal and high-level groundwater occurrences at the survey areas. These TDEM surveys were conducted along four (4) mauka-makai transects located near Kukuihaele, Kapulena, Paauhau and Paauilo along the Hamakua Coast. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for well placement and well completion depths."Item type: Item , Geophysical surveys for assisting in determining the ground water resources, Kaupulehu area of North Kona, Island of Hawaii(Blackhawk Geosciences, Inc., 1999-08-16) Nance, TomThe main objective of the geophysical survey was to assist in characterizing the hydrologic regime in the Kaupulehu study area for a proposed ground water well. Ground water resources can occur on the Island of Hawaii basically in two modes: • In a basal mode, where a lens-shaped body of fresh water floats on saline water, and • In a high-level mode, where the ground water occurrence is controlled by subsurface damming structures. The surficial volcanic rocks are generally highly permeable and this allows rainwater to infiltrate directly downward through the island mass. Previous TDEM surveys on the Hawaiian Islands have reliably mapped the boundary between fresh water in the basal mode and high-level water occurrences. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for well placement and completion depths."Item type: Item , Geophysical surveys for assisting in determining the ground water resources, North Kohala site, Island of Hawaii(Blackhawk Geosciences, Inc., 1998-11-03) Nance, TomThe main objective of the geophysical survey was to assist in characterizing the hydrologic regime in the North Kohala study area for a proposed ground water well. Ground water resources can occur on the Island of Hawaii basically in two modes: • In a basal mode, where a lens-shaped body of fresh water floats on saline water, and • In a high-level mode, where the ground water occurrence is controlled by subsurface damming structures. The surficial volcanic rocks are generally highly permeable and this allows rainwater to infiltrate directly downward through the island mass. In the Hawi area, ground water was expected to occur as both a deep basal fresh-brackish water lens and possible high-level water occurrences at locations above subsurface damming structures (i.e, dikes; rift zones). Previous TDEM surveys on the Hawaiian Islands have reliably mapped the boundary between fresh water in the basal mode and high-level water occurrences. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for well placement and completion depths."Item type: Item , Geophysical surveys for assisting in determining the ground water resources, Honomalino and Kapua areas, Island of Hawaii(Blackhawk Geosciences, Inc., 1998-11-11) Nance, Tom"This report contains the procedures and results of geophysical surveys conducted to assist in determining the ground water resources on properties in the Honomalino and Kapua areas, Island of Hawaii. The surveys were performed by Blackhawk Geometries (Blackhawk) for MacFarms of Hawaii, Inc. (MacFarms) during October 5 to October 9, 1998. The geophysical method employed during this survey was Time Domain Electromagnetic (TDEM) soundings. During these surveys, TDEM soundings were located on Hawaii State Parcel TMK 8-9-1-02 and on property owned by MacFarms as shown on Figure 1-1. TDEM data previously acquired in a 1990 survey for MacFarms has been incorporated into this report. The Honomalino and Kapua areas of Hawaii are in the South Kana District in the southwest portion of the island. The main geologic feature in this area of the Island of Hawaii is the southwest rift zone, which extends away from the summit of Mauna Loa Volcano to the coastline near South Point (Stearns and Macdonald, 1946). The nearest mapped volcanic cone (Puu Ohohia) associated with the southwest rift zone, is located approximately five miles east of the study area. The main objective of the geophysical survey was to assist in characterizing the hydrologic regime in the Honomalino and Kapua areas for a proposed ground water well. Ground water resources can occur on the Island of Hawaii basically in two modes: • In a basal mode, where a lens-shaped body of fresh water floats on saline water, and • In a high-level mode, where the ground water occurrence is controlled by subsurface damming structures. The surficial volcanic rocks are generally highly permeable and this allows rainwater to infiltrate directly downward through the island mass. The basal ground water lens extends from the outer edges of subsurface structures (i.e., dikes) to a discharge area near the shoreline. In the Honomalino and Kapua areas, ground water was expected to occur as a deep basal fresh-brackish water lens. Previous TDEM surveys on the Hawaiian Islands have reliably mapped the boundary between fresh water in the basal mode and high-level water occurrences. Geophysical surveys, combined with other hydrogeologic information, are used to provide optimum locations for well placement and completion depths."Item type: Item , Geophysical surveys for assisting in determining the ground water resources at the Kaupulehu, Puaa, and Keauhou project areas, Island of Hawaii(Blackhawk Geosciences, Inc., 1993-09-23) Nance, Tom"The main objective of the geophysical surveys at the Kaupulehu Project-Area 1 was to determine if high-level ground water occurs at locations above Highway #190. A ground water damming structure has been mapped by previous TDEM surveys near the Puaa Project-Area 2 at locations both north and south of the property, and the objective of the geophysical at Puaa survey was to determine if high-level ground water occurs above Highway #180 on the property. A main ground water damming structure (parallel to the coast line) is inferred to occur in the Keauhou Project-Area 3 and recent drilling results indicate that secondary damming structures may exist within the region above the main damming structure. The primary objective at the Keauhou Project Site was to test several different geophysical methods to attempt to map the position of the secondary damming structure(s). There are significant cultural features (power lines, pipelines, houses, etc.) in the Keauhou area. These features are known to significantly affect many geophysical methods, in particular, electrical and electromagnetic methods such as TDEM and also magnetic methods. Another objective of the survey in the Keauhou area was to test geophysical methods for their applicability in built-up (cultural) areas."Item type: Item , Time domain electromagnetic surveys near Kukaiau, Hamakua Coast, Island of Hawaii(Blackhawk Geosciences, Inc., 1992-07-17) Nance, Tom"This report contains the results of time domain electromagnetic (TDEM) surveys conducted near Kukaiau, on the Hamakua Coast, Island of Hawaii. The survey was performed by Blackhawk Geosciences, Inc. (BGI) for Frank S. Hahn during June 1992. The overall objective of the survey was to assist in defining the potential fresh water resources at a study site which lies about 12,000 ft south of Kukaiau at an elevation of 2,200 ft. To gain an understanding of the geohydrologic regime at the study area, measurements were taken on a south to north transect which extends from the study area towards the ocean across land owned by Hamakua Sugar. The two major factors which influence the location and availability of fresh ground water in this geologic setting are (i) the elevation of the fresh water - salt walter interface for basal ground water occurrences, and (ii) the location and attitude of potential ground water damming structures (e.g., dikes) and aquitards. Thus, the specific objectives of this survey were to • map the fresh water - salt water interface underlying the survey area, and • identify and map geologic structures or lithologic units which may affect ground water distribution. In IDEM surveys the electrical resistivity of the subsurface is measured. Previous IDEM surveys on the Hawaiian Islands have shown large resistivity contrasts to occur between volcanics saturated with fresh water and saline water. In most cases, also significant resistivity contrasts exist between geologic structures and unweathered volcanics."Item type: Item , Geophysical surveys for characterizing the hydro-geologic regime in the vicinity of Kealakehe, Hawaii(Blackhawk Geosciences, Inc., 1991-06-11) Nance, Tom"The primary objective of the geophysical survey was to determine the elevation and thickness of the lens of fresh water floating on salt water. Fresh water in these settings is found in two environments: 1. Dike-confined waters -- Typically, 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."Item type: Item , Geophysical surveys for characterizing the hydro-geologic regime of the Puu Anahulu area of North Kona, Island of Hawaii(Blackhawk Geosciences, Inc., 1991-12-03) Nance, Tom"The main objective of the geophysical survey was to characterize the hydrologic regime near Puu Anahulu. In the Hawaiian islands, the volcanic rocks are generally highly permeable and rain water rapidly percolates into the ground and migrates downward to the water table. Fresh water in these settings is found in two environments: 1. Dike-confined waters -- Typically, 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."Item type: Item , Geophysical surveys for ground water evaluation, South Kona, Island of Hawaii(Blackhawk Geosciences, Inc., 1991-05-22) Nance, Tom"The primary objective of the geophysical survey was to determine the elevation and thickness of the lens of fresh water floating on salt water. Fresh water in these settings is found in two environments: 1. Dike-confined waters -- Typically, 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."Item type: Item , Geophysical surveys for ground water evaluation, North of Waikoloa Village, Island of Hawaii(Blackhawk Geosciences, Inc., 1991-12-16) Nance, Tom"The objective of the geophysical survey was to add additional TDEM information to the existing (1988 and 1990) data set along Kamakoa Gulch, North of Waikoloa Village. The concepts for using geophysical surveys for ground water evaluations can be understood using the generalized hydrogeologic cross section. In the Hawaiian islands, the volcanic rocks are generally highly permeable and rain water rapidly percolates into the ground and migrates downward to the water table. Fresh water in these settings is found in two environments: 1. Dike-confined waters -- Typically, 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."
