Description:

Development of Groundwater Well Field to Supplement Public Water Supply, North Carolina 2008

Analytical Services, Inc. (ASI) personnel provided assistance to a County Government in Western North Carolina to develop a supplemental groundwater supply for an existing public water supply (surface water) system. The project initially involved a preliminary assessment of a County property to evaluate its potential for groundwater development. Upon review of ASI’s findings, the County authorized a more comprehensive assessment of the property which consisted of approximately 400 acres of heavily forested terrain. Fracture trace analysis and geophysical surveys were completed and the results used to identify target well locations. ASI worked with NC DENR staff to permit the well sites and drilling commenced. ASI managed the well drilling operations and field geologists were onsite to carefully log the wells during construction.

Bedrock geology underlying the site is characterized by granitic gneiss and schist. Structurally the site lies within the Brevard Fault Zone. Favorable groundwater yields were encountered at many of our drilling targets. Nine wells were completed with yields that were deemed suitable for aquifer pump testing. An aquifer testing plan was developed that included two testing events. The first event being the simultaneous testing of four of the higher yielding wells for 48 hours and the second event being the simultaneous testing of five wells. Observation wells were equipped with down-well dataloggers during the testing to record groundwater level data that were used to interpret hydraulic connections between specific wells. The aquifer testing consisted of constant rate pumping. The measured combined pumping rate from the nine (9) wells at the conclusion of the testing was greater than one million (1,000,000) gallons per day. Groundwater samples were collected near the end of the pump testing and submitted to a State certified laboratory for quality analyses.