Los Angeles, Jun 25 (IANS): California's Pacific Gas and Electric Company (PG&E) has agreed on a $5.9 million-settlement for once-through cooling water discharges from its Diablo Canyon nuclear power plant.

The settlement, reached with the Central Coast Regional Water Quality Control Board, was the result of a thorough Water Board investigation into alleged violations stemming from the plant's use of water from the Pacific Ocean in its cooling system since 1985 and was officially filed on May 25 with the San Luis Obispo Superior Court, reports Xinhua news agency.

According to Thursday's report by Cal Coast News, the nuclear power plant takes in water from sea to condense steam after it passes through two electrical generators in a process called "once-through cooling" and the used water is then released back into the ocean.

Under the power plant's local permit, public water was allowed to be piped from nearby sea area into the ocean, but environmentalists argued the discharge of water into the ocean harmed marine life.

Ailene Voisin, spokesperson for the Central Coast Regional Water Quality Control Board, estimated the thermal discharge to be about 20 degrees Fahrenheit (11.1 degrees centigrade) above the ambient ocean temperature in that area and that alterations to the nearby ecosystem "are well-documented and well-understood", yet with "no feasible technological alternatives or modifications".

Another problem was that the induction system that pumps water from Diablo Canyon into the power plant also sucked up an estimated 1.5 billion fish larvae per year, causing disruptions to the reproductive cycle of local fish.

The Water Board said in a press release on June 18 that the settlement funds received from PG&E would be used for water quality projects that benefit the region.

In addition to the settlement, the release indicated that PG&E had also been making yearly payments to mitigate the issues from their overheated discharges.