Cleanup on a Large Scale

The San Gabriel Basin yields 200,000 ac ft of groundwater a year from 400 supply wells. This water makes up 95% of the Valley’s water supply. Already 30% of the water pumped from the Basin has been affected by contamination. An EPA Superfund investigation began in 1984 to develop a comprehensive sampling program. Because of the limited alternative water supply, the basin’s groundwater must be salvaged. But more than 50 separate entities own water rights. Any solution intended to reduce the spread of contamination will require cooperation among the different water users to manage the problem through controlled pumping. Plans must also include alternate sources of water for those with water rights. The large number of possible contamination sources and potentially responsible parties, many unidentified at this point, requires enormous amounts of manpower to investigate and verify. In situations where contaminated areas have multiple sources, potentially responsible parties often spend considerable court time to determine blame and payment responsibility. One thing is clear: cleaning up the problem will be very time consuming and very expensive.