Space Force officials are still unsure how much soil has been contaminated after a fuel tank spilled 700 gallons of diesel fuel last week at the service's observatory nestled atop a Hawaiian volcano.
Brig. Gen. Anthony Mastalir, commander of the United States Space Forces Indo-Pacific, said during a press conference Monday that workers plan to remove 200 cubic feet of soil at least six feet deep at the Maui Space Surveillance Complex to determine just how deep the fuel went into the ground.
"At that point, we will take measurements to better understand what that level of contamination is," Mastalir said. "It's impossible to know at this point exactly how deep the diesel fuel was saturated into the topography."
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Last week's diesel spill at the Maui Space Surveillance Complex, located on the 10,023-foot summit of Haleakalā, has led to protests by local activists and is the most recent military contamination incident in Hawaii following the massive 2021 fuel spill at the Navy's Red Hill Bulk Fuel Facility in Honolulu.
The latest spill occurred when a diesel fuel pump for a backup generator failed to shut off on the evening of Jan. 29, according to the Space Force. Mastalir said a float -- a piece that helps monitor fuel levels -- inside the fuel tank was defective.
"We currently assess that the cause of this spill was a damaged float within the generator's main fuel tank," Mastalir said. "Specifically, the evidence suggests that a power surge was the likely cause of this damage."
Haleakalā is culturally and religiously significant for native Hawaiians, according to the National Park Service. Many local groups have opposed military development in the area for decades.
In the days following the diesel leak, one local protest group named Kāko'o Haleakalā has protested the site carrying numerous signs, some that read "U.S. Department of Defense Death" and "Time To Haalele" -- which translates to "Time To Desert," according to Ulukua, a Hawaiian electronic library service that provides a dictionary.
An online petition from the protest group titled "End the Maui Space Surveillance Site (MSSS) lease renewal in 2031" had garnered upward of 300 signatures as of Tuesday morning.
"The recent contamination incident at Haleakalā is yet another example of the U.S. military's detrimental impact on Hawai'i's sacred places, natural resources, and people," the online petition reads. "Kākoʻo Haleakalā remains steadfast that no further desecration should take place atop this, or any other mountain."
Mastalir said he promised to "develop a remediation plan that is consistent with legal requirements and sensitive to the local and cultural imperatives" and has been in touch with Hawaii Gov. Josh Green regarding the issue.
"We are going to continue to work to rebuild the trust with all Hawaiians, with these native Hawaiians and their organizations, so that we, given the privilege to operate here, will do so safely and respectfully," Mastalir said during his press conference Monday.
Concerns over the fuel spill have also been echoed in Washington by Sen. Mazie Hirono, D-Hawaii, who said she will push the Department of Defense through her position as a member of the Senate Armed Services Committee to address its aging infrastructure on the islands.
"Yet again, families and communities across Hawaii are paying the price for the military's aging infrastructure -- this time at the summit of Haleakala on Maui, home to endangered species and an area sacred in Native Hawaiian culture," Hirono told Military.com in an emailed statement last week. "The repeated leaks of fuel and other toxic substances endanger our environment and the health and safety of people in Hawaii."
The 700-gallon fuel spill at the Maui Space Surveillance Complex, which is home to the DoD's largest optical telescope, according to the Space Force's website, is only a fraction of the 20,000 gallons of jet fuel spilled at Red Hill.
More than 93,000 people living in military housing on and around Pearl Harbor were affected by the massive jet fuel spill in 2021. More than 5,000 gallons eventually seeped into the ground and tap water.
The contamination forced thousands to leave their residences, and those who stayed had to rely on bottled water to get by. In 2022, the Pentagon announced that the World War II-era bulk fuel farm would be closed and drained.
-- Thomas Novelly can be reached at thomas.novelly@military.com. Follow him on Twitter @TomNovelly.
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