Just offshore from Waikiki’s Kaimana Beach, a fishing boat transporting foreign workers destined for low-paying jobs in Hawaii’s fishing fleet lodged itself on the reef last month.

The stranded vessel has been leaking oil and diesel ever since in an area prized by swimmers and surfers, and there was a visible sheen around the boat this week.

The grounding of the 79-foot Pacific Paradise illustrates a potential environmental impact of the Hawaii fishing industry fleet’s practice of transporting foreign workers by boat.

The industry already faced criticism following a 2016 Associated Press investigation revealing that the workers from Southeast Asia and Pacific nations work without visas, some making less than $1 an hour and living in squalid conditions.

Swimmers and surfers say they feel and smell the petroleum even when they’re in the water far from the wreck. Some visitors mistakenly assume the crippled boat is a tourist attraction.

The wrecked vessel had about 1,500 gallons of diesel and hydraulic oil left in its tanks when the boat caught fire days after the October 10 grounding.

Coast Guard spokesman Lt. Cmdr. Scott Carr this week played down the possibility of environmental damage, saying there is a sheen on the w ater but that diesel fuel evaporates quickly and that surf breaks it apart.

“The environment is fairly resilient,” Carr said.

Efforts to remove the boat have failed so far, but swimmer Chris McDonough said more should be done. He said his surfer friends can smell and feel the fuel in the water hundreds of yards away.

“I could feel it on my skin,” the Honolulu resident said, adding that the previous attempts to remove the boat seem “like an inadequate response.”

The boat is a longline tuna fishing boat that struck the shallow reef in the middle of the night as it headed to drop off the foreign workers for their transfer to other fishing boats.

No one aboard called for help when it ran aground and the Coast Guard is investigating. The crew members were taken into U.S. Custom and Border Protection custody and released to the boats that had contracted to bring them to the state.

While a salvage crew was preparing to tow the boat away, the vessel caught fire and sent up thick plumes of black smoke as the workers jumped off the burning deck and into the ocean. Another attempt using a powerful tug boat and specially designed cables also failed.

Officials designated a 500-yard safety zone in the water around the wrecked vessel. But they do not continuously monitor the site and the beach closest to the boat has no signs or warnings for people to stay away.

Some tourists had no idea the wreck was recent and leaking.

“I thought it was a tourist thing, I thought it was some attraction or something,” said Lauren Benschoter, of Adrian, Mich., on vacation with her husband, Bryan.

The wreckage is also near the Waikiki Aquarium, which pumps in seawater for its marine life. Water samples taken there and at the beach closest to the boat have shown no signs of fuel or oil, officials said.

Keith Kawaoka, Hawaii’s deputy director of environmental health, said “people should, for their own safety, stay away from that area.”

The oil and diesel fuel pose possible risks to other nearby reefs and several endangered species, including an endangered Hawaiian monk seal that could be seen swimming near the boat Wednesday.

Officials are also concerned about the impact of the fuel on green and hawksbill turtles and have said the extent of damage to the coral won’t be known until the boat is removed.

The Coast Guard has hired experts to review salvage plans proposed by the boat’s owner, TWOL LLC. The company’s lawyer, Bryan Ho, asked The Associated Press to send him questions by email but said Thursday he could not immediately respond to them.

Fishing boats regularly transport groups of foreign workers to Hawaii because the men do not have visas and are not permitted to fly into the country.

There were 19 foreign men from Vietnam, Indonesia, the Philippines and Kiribati with one American captain on the Pacific Paradise when it hit the reef.

Hundreds of foreign workers are currently confined to fishing vessels in Honolulu for years at a time. Legislation introduced Nov. 2 in Congress could change the way the system works.

The Sustainable Fishing Workforce Protection Act would offer workplace protections a year after the AP’s investigation found that the fleet is crewed by about 700 men who are confined to their boats for the duration of their contracts, often a year or two at a time.

While some of the 140 boats are clean and safe, AP found some fishing crews living in squalor, forced to use buckets instead of toilets and suffering running sores from bed bugs. There have been instances of human trafficking, active tuberculosis and low food supplies.

The bill would close a loophole in the law that has allowed the Hawaii fleet to employ the workers for a fraction of the pay an American worker would get, in part by collecting them by boat from Pacific islands.