United States Army Corps of Engineers

One of our professionals conducted ground water monitoring including depth-specific sampling of three municipal supply wells at the San Gabriel Superfund site in Southern California and coordinated preliminary design for a packed-column air stripping facility for remediation of trichloroethylene-impacted ground water for the United States Army Corps of Engineers.

Water Resources Evaluation, Catalina Island, Los Angeles County, California

Development of additional water resources was required as a condition for permitting of a proposed hillside attached housing development north of the city of Avalon on Catalina Island, offshore of Los Angeles, California. Water resources are a critical commodity on the island. Multiple potential sources were investigated, including pumping from defunct mine workings, development of natural springs and seeps, desalination of sea water, as well as artificial recharge of the alluvial aquifer above the city. For the latter alternative source a temporary storm water retention basin was constructed up-canyon of the municipal golf course, and monitoring wells as well as City of Avalon municipal supply wells were utilized first to conduct a 24-hour pumping test, and then in monitoring water levels during several winter storm events, in a quantitative evaluation of the potential for artificial re-charge of the aquifer.

Water Resources Development, Pearblossom, California

The study of an alluvial aquifer descending northward from the San Gabriel Mountains involved research on surrounding water wells, a geologic mapping phase for well siting, drilling, and development of a water supply well for multiple proposed homesites in a high desert area of southern California. The well was successfully sited, drilled and developed.

Water Re-charge Study, Lemon Cove, California

Proposed expansion of an existing sand and gravel mine called for study of pit de-watering and re-charge of extracted potable groundwater elsewhere on an alluvial fan near the town of Lemon Cove, California. Existing ground water monitoring wells and observation wells drilled and installed for the project were utilized in performing two 24-hour pumping tests to determine aquifer characteristics. The study demonstrated the feasibility of de-watering the proposed pits on a phased basis throughout the modeled life of the mine expansion, without impact on availability of ground water for irrigation and other uses by down-gradient stakeholders.