GAMA: Groundwater Ambient Monitoring & Assessment Program

SPECIAL STUDIES PROJECT

LLNL has conducted several groundwater special studies including nitrate, wastewater, and groundwater recharge. LLNL scientists apply Tritium-Helium age dating technique, isotopic composition of water and nitrate molecules to determine source(s), and presence of noble gases to determine recharge source and condition, as well as sophisticated computer modeling techniques.  UC Davis has also contributed to GAMA Special Studies.

Completed LLNL studies

• Nitrate sources, fate & transport
  • Dairies
• Nitrate management plan study
  • Llagas Basin (Gilroy)
  • Chico Basins
• Nitrate Occurrence and Source
  • Study of fate and transport, and its relation to land usage (fertilizer, wastewater, and/or agricultural)
    • Orange County
    • Livermore
• Wastewater Indicator study
  • Septic Systems affect on shallow groundwater
  • Areas irrigated by recycled water
    • Gilroy
    • Livermore

Seven projects have been completed; five reports have been published with numerous scientific papers and presentation.  One paper received the Hitchon Award from the International Association of Geochemistry.    

In progress LLNL studies

• Groundwater Recharge
• Continuing studies on changes in chemistry of groundwater recharged by surface waters.  
• Developing a field deployable apparatus for extraction and collection of dissolved gasses from groundwater samples.

Endocrine Disruptor Analysis Development (UC Davis)

UC Davis scientists are working to develop a biologically-based screening assay to identify endocrine-disrupting chemicals (EDCs) in water. The method entails exposing “medaka” species of fish to EDCs while alive.  After a period of exposure, the DNA is extracted from the fish tissue to analyze by microarray chip to evaluate changes in gene expression.  

( updated 10/15/07 )