The Navy on Monday said it would release video footage of last week’s spill of toxic fire suppressant chemicals at Red Hill to federal and state environmental regulators, but not the public claiming that doing so could impede its investigation into the latest accident at its massive underground fuel facility.

The Navy’s decision to withhold the footage from the public was immediately panned by the Hawaii Sierra Club, which called it “outrageous.”

“The Navy continues to talk about transparency while hiding evidence of its repeated contamination of our environment,” said David Kimo Frankel, an attorney for the environmental group.

For months, since last year’s Red Hill fuel spill that contaminated the Navy’s drinking water system, the Navy has vowed transparency as it has sought to repair its relationship with local leaders and the community. But the latest environmental screw-up is again straining relationships, including with the Honolulu Board of Water Supply, which expressed frustration last week that it had not been immediately informed of the spill.

The BWS said Monday that it was disappointed in the Navy’s decision not to release video of the spill.

“This decision is not in keeping with the Navy’s promise to increase transparency and improve public confidence,” the water board said in a statement. “AFFF contains chemicals that can persist in the environment and get into our groundwater aquifer. The video is information critical to our understanding the impact of the AFFF incident to our sole source aquifer now and into the future.”

Top Navy officials initially told the media last week that there was no video footage of the spill. But on Friday, the Navy walked back that statement, saying that there actually was video from one of the Red Hill cameras that was positioned in the area. The Navy said a second camera was broken.

The Hawaii Department of Health regulates the Red Hill facility, along with the U.S. Environmental Protection Agency. DOH told the Star-Advertiser on Friday that it had requested the footage after being made aware of its existence by the media.

The Navy said on Monday that the video will be shared with the agencies “to facilitate the DOH and EPA’s investigative and regulatory functions.”

“The video and other evidence will not be released publicly at this time as doing so may impact the integrity of the investigation,” the Navy said in a press release. “The video will be made available when it is determined that doing so will no longer affect the investigation.”

The Navy did not immediately respond to a question about why it believed releasing the footage would compromise its investigation.

On Nov. 29, hundreds of gallons of concentrated aqueous film-­forming foam (AFFF), which is used to contain fuel fires, leaked from a pipeline at Red Hill. AFFF contains PFAS, so-called “forever chemicals” that are slow to degrade in the environment, alarming regulators and environmentalists.

The Navy said that about 1,100 gallons leaked, but a report to DOH last week listed the amount as 1,300 gallons. The Navy has yet to explain the discrepancy other than to tell the Star-Advertiser that the 1,100 gallons were an initial estimate.

The Navy on Friday announced Maj. Gen. Richard J. Heitkamp of the U.S. Army Reserve had been appointed to investigate the “operations, procedures and system design that may have led” to the AFFF release, ”including the cause of the incident and any fault, liability, neglect or responsibility.”

The Navy said that the investigation is expected to take 30 days, though didn’t indicate when any findings would be publicly released.