In an unusually strong warning, the general manager of the Southern California Metropolitan Water District says the impact of toxic wastes on the Southland's drinking water supply "is highly uncertain and the subject of considerable concern."
Carl Boronkay's remarks, prepared for delivery in New York on Thursday, represented a sharp departure from past assessments by local water officials, who have long downplayed the extent of toxic waste danger to the water supply. The only comparable warning from the MWD was in a staff report issued last year.
Boronkay said that in the past, pollution of underground sources "have been minimized by relocating production facilities and by blending well water with other supplies to bring concentrations (of toxins) down to acceptable levels." But now, he said, "The future impact of toxic wastes on water supplies is highly uncertain and the subject of considerable concern to water suppliers.
"In the future, toxic wastes will impact water supplies in ways that are not widely understood," Boronkay said.
His address at a Columbia University law school conference on environmental policy will be delivered by Dr. Wiley Horne, the MWD's director of resources, because Boronkay cannot attend the meeting. But aides said the general manager stands by the text he prepared.
Joint Study on Pollution
Boronkay prepared the statement as the MWD and an environmental group, the Environmental Defense Fund, began putting into effect a joint study on ways of reducing pollution at industrial plants and other sources of toxic wastes.
The EDF, which had been critical of MWD environmental policies for many years, and the district will begin a two-year study of sources of pollution in a key area, the Chino Basin in San Bernardino and Riverside counties, and come up with ways the infiltration of toxins in the ground can be reduced.
The city of Los Angeles has given the EDF $150,000 toward its $415,000 share of the costs, reflecting its concern about the threat to the city water supply, which comes from the Owens Valley, from MWD Colorado River sources and from underground San Fernando Valley wells, some of which have been hit by toxic pollution. The MWD is also putting up $415,000.
The Metropolitan Water District supplies water to agencies in Ventura, Orange, Los Angeles, Riverside, San Diego, San Bernardino and Riverside counties.
By choosing the Chino Basin for its study, the MWD will be examining underground water supplies that are becoming increasingly important because of fast-growing residential and commercial development in the area. In addition, the MWD has proposed using huge natural underground reservoirs there to store water imported from Northern California. With that storage capacity, the MWD would be able to reduce water importation from the north during dry years, possibly easing Northern California political opposition to sending water south.
Reduce Import Need
In his remarks, Boronkay referred to the need for toxin-free underground supply and storage basins to reduce the need to import more water.
"Groundwater quality problems may seriously reduce the available production from a groundwater basin," Boronkay said. "Inevitably, this will increase demands for more surface water. In effect, toxic waste problems in Southern California extend hundreds of miles eastward to the Colorado River and even far northward to the Sacramento-San Joaquin Delta."
Contamination of the underground reservoirs would limit their use for storage of water during wet years and threaten "one of the key management tools required to resolve the technical and political controversies that have plagued Western water policy for decades," Boronkay said.
Boronkay also said that the threat of toxic wastes will result in higher drinking water standards.
"The water industry will supply only water that is healthful, based upon the best possible scientific information available," Boronkay said. "Future drinking water standards must somehow be established that consider the health consequences of exposure to particular substances in water and the costs and risk trade-offs of achieving the mandated standards."
The Boronkay remarks are another example of increased MWD concern about pollution.
In 1986, the district's board drew heavy environmental criticism when it voted to remain neutral in the campaign over Proposition 65, the toxin-control measure designed to protect the board's water supply. Afterward, the board's staff issued a report saying that some underground supplies may not meet new state and federal standards.
That was the first indication from the staff that some of its underground water sources face potential pollution threats.