Time domain electromagnetic surveys for assisting in determining the groundwater resources on property located in the South Kona district, below Kealakekua, Hawaii

Abstract

"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."