In the largest enforcement action against a bottled-water business in Hawaii, a firm that distills deep seawater has agreed to pay $2 million in a settlement with the state Department of Health.

The state last September fined Koyo USA Corp., maker of MaHaLo Hawaii Deep Sea water, $5 million for using an unauthorized manufacturing process.

The Health Department said the water did not pose a health risk, and that it was not subject to a recall or embargo.

Koyo takes water from 3,000 feet deep off the Kona Coast, filters it and sells it as drinking water that is "naturally clean, pure, cold and filled with healthy minerals and nutrients," the company website says.

The water is marketed extensively in Japan.

Gary Gill, state deputy director for environmental health, said that under its permit, Koyo USA Corp. could bottle only water that had passed through reverse osmosis filters.

"Koyo mixed water that had not passed the reverse osmosis filters into its final product," Gill said.

He said the fine amount became large because the improper process had been used continuously for nearly five years, from July 7, 2006, to May 19, 2011.

Gill said because Koyo disinfected its product, state health officials determined there was no health threat to the public.

The $2 million settlement will be used to support the department’s drinking water, food safety and laboratory programs, officials said.

According to its website, Koyo produces about 600 bottles of water an hour and has the capacity to produce 1 million bottles a day.

Koyo spokesman Mitchell Thompson said the firm has made changes to its filtration process to satisfy health requirements.

"We are pleased to know the Department of Health confirmed that Koyo USA’s bottled deep seawater was safe for consumption at all times," Thompson said.

He said the fine stemmed from a "technical violation" involving Koyo’s filtration process and that there was no admission of wrongdoing in the consent order.

He said the firm, a major exporter of Kona deep seawater to Japan, has been a tenant at the Natural Energy Laboratory of Hawaii Authority in West Hawaii since 2002.

Thompson said the firm is pleased the fines were earmarked to support and enhance the health of Hawaii’s people. "We are pleased to know the funds will be put to good use," he said.