HONOLULU (KHON2) — After months of preparation, the Navy has started defueling more than a hundred million gallons of fuel at Red Hill. For the families who were sickened by the fuel contamination, it starts a period of anxiety as they fear that something else can go wrong.

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The defueling process is led by the the Department of Defense’s Joint Task Force Red Hill, which has started removing 104 million gallons of fuel from large underground tanks that sit above the aquifer. Officials said the fuel will be removed through gravity draining using pipelines running through three miles of tunnels.

The fuel will then be loaded into tanker ships and shipped to other storage facilities. The plan has been approved by the Department of Health and the US Environmental Protection Agency, and all parties gave the public assurances that it will be safe.

“I am on alert, I’m hyper vigilant about everything that could happen. So no, me personally no, I will worry every single day until defueling is over,” said Lacey Quintero.

Quintero and her family are among the thousands who got sick after the fuel contaminated the water two years ago.

“We were all violently ill and it kind of continued until we moved out into the hotels,” she said.

“When most of that fuel is out and actually when they get the last drop out, that’s when I’ll be able to rest easy,” said Ernie Lau, chief engineer of the Honolulu Board of Water Supply.

Lau knows all too well that so many things can go wrong. He adds that BWS needs more involvement in determining how much damage has been done to the aquifer below the tanks.

“I think it’s appropriate that we be allowed greater access to the information and maybe greater involvement in these important discussions that are happening,” said Lau.

The tanks sit about 100 feet above the aquifer. Lau says there’s porous volcanic rock in between, and it’s important to see how much fuel has seeped into that volcanic rock.

“How much fuel is hung up in that area between the bottoms of the tank about 100 feet above the top of the aquifer below and can some of that be removed before it reaches the underground aquifer?” said Lau.

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Joint Task Force Red Hill sent an update on Monday afternoon saying more than 100,000 gallons were defueled in about an hour and a half.

The plan is to fill up the tankers, which hold 10 million gallons, in about 52 to 56 hours. Officials say most of the fuel should be taken out by mid-January.