State and federal regulators have rejected key provisions of the Navy’s plan to improve the Red Hill Bulk Fuel Storage Facility following a 27,000-gallon leak in 2014 — saying the proposal for the World War II-built tank farm “lacks detail, clarity, rationale and justification.”

In a letter dated Monday, the U.S. Environmental Protection Agency and state Department of Health said they “disapprove” of the Navy’s September 2019 plan to protect groundwater near the site and are giving the Navy and Defense Logistics Agency “an opportunity to cure the deficiencies and resubmit the decision document.”

In its tank upgrade analysis, the Navy “has not demonstrated to the regulatory agencies that the proposed alternative is the most protective of the groundwater and drinking water,” the notice states.

The Navy selected the least expensive of the tank upgrade options and “the least protective,” according to the Sierra Club of Hawaii.

“This is the latest example of how the Navy does not take the protection of Oahu’s drinking water seriously,” Jodi Malinoski, Sierra Club of Hawaii policy advocate, said in a release. “It’s been five years and still the Navy can’t provide a meaningful plan to protect our water from their antiquated tanks.”

Among the concerns, the agencies said a Navy plan to have “double-wall equivalency secondary containment” or remove the fuel from Red Hill in approximately the 2045 time frame “requires further discussion.”

The term “double-wall equivalency” itself needs to be defined, the regulators said. Underground storage tanks with double walls are typically designed to meet secondary containment requirements, and secondary containment usually includes an inner and outer barrier with an in-between space monitored for leaks, the letter said.

“The Navy remains committed to keep the water safe to drink while safely operating the storage facility that is vital to the defense of our nation and also available to support the state in times of crisis,” Capt. Gordie Meyer, commander of Naval Facilities Engineering Command Hawaii, said in an email.

The Navy and the Defense Logistics Agency “will be working with the regulators, reviewing their feedback and outlining a plan and schedule to provide them the amplifying information they are requesting,” he said.

The Navy must provide a detailed comparison of how the proposed secondary containment equivalency will perform against other options, including traditional secondary containment such as tank within a tank, the agencies said.

An “advisory order on consent” entered into by the parties specifies that all tanks in operation shall have approved leak improvements by September 2037 or be taken out of use, and a Navy-specified time frame of 2045 “does not appear to comply” with that agreement, according to the notice.

The Navy proposed a “comprehensive tank restoration” and decommissioning of nozzles that could be sources of leaks “combined with coating applications and improved testing, monitoring, modeling, sampling, and analysis throughout the facility’s layers of protection.”

Also considered by the service were six other options, including keeping the single-wall steel liner while adding a full epoxy coating, along with replacing the steel liner.

Double-wall options included new carbon steel with interior coating, a composite tank with stainless steel, and a carbon steel tank within a tank. Alternatively, a new tank farm also was contemplated.

In 2018 the Navy estimated the cheapest single-wall option would cost $180 million to $450 million. The tank-within-a-tank option was pegged at between $2 billion and $5 billion. Replacing the tank farm with similarly fortified underground or concrete-encased fuel tanks would run as much as $10 billion.

The Navy said the 20 tanks within Red Hill represent “critical infrastructure for the nation’s defense” and are steel-lined concrete up to 4 feet thick which store millions of gallons of jet or marine fuel used by the military.

Since 2006 the Defense Department has invested $260 million in Red Hill, with modernization continuing. “Public records confirm that all drinking water near Red Hill remains safe,” the Navy said.

A classified U.S. Indo-Pacific Command fuel study was underway in 2019 which the Navy said would determine strategic fuel storage requirements across the region and “be used to help inform how much bulk fuel storage will be required in Hawaii.”

The Sierra Club of Hawaii said there is no better option for Oahu’s water supply than relocation of the Red Hill fuel farm.

After the Navy studied tank upgrade options, “to no surprise, the Navy’s preferred choice — the least protective and least expensive option — is to keep the original, corroding steel tank liner, coat it with epoxy and explore installing a water treatment plant to filter toxic chemicals from Oahu’s drinking water in the case of another major leak,” the environmental group said on its website.

Much of the concern over Red Hill centers on the tanks’ location 100 feet above the water supply aquifer that is the principal source of drinking water for more than 750,000 Oahu residents. The aquifer lies in saturated volcanic rock.

The Navy admitted its “double-wall equivalency” plan relies on future technology that does not now exist — which the Sierra Club said is “not actually a double-walled solution.”

The regulatory agencies said 411 written and 45 oral comments were received at a public hearing on the Navy plan, and most “were not in support of the Navy and DLA’s proposed tank upgrade alternative.”

In response to the assertion that the Navy should be required to provide secondary containment, the regulatory agencies said the Navy must first demonstrate the relative environmental benefits of each option — which then will be subject to approval.

“Based on the decision documents submitted, the regulatory agencies believe that the Navy did not provide adequate analysis or justification for their selection,” the notice said. “The Navy has only provided generalized statements that there are substantial constructability risks associated with retrofitting secondary containment into the existing tanks.”

The EPA and Health Department said they realize that “many of our issues with the collective (Navy) decision document may require substantial effort and time to address” beyond a standard 30 days, and the Navy can request a meeting within that time period to review the letter sent by the agencies.