NANAKULI — Armed federal agents yesterday raided a suspected illegal dump for hazardous waste and arrested two men.

The 10-acre site at 87-1161 Hakimo Road is believed to have five deep holes in which the dump operator would deposit chemical and other waste, charging companies less than what proper disposal sites charge, said Ed Kubo, U.S. attorney for Hawai'i.

"This type of illegal dumping not only hurts our environment but it has the potential of harming innocent children and families living nearby," Kubo said.

Neighbors also said they have heard frequent gunfire from the property and see a lot of traffic going to and from the site, which is home to about a dozen people.

"When my family and I are out there and we hear shots, we hit the ground because there's no telling where the bullets are going to end up," said Wayne Keanu, who has lived on Hakimo Road for more than a decade.

Agents from the Environmental Protection Agency's Office of Enforcement and Compliance Assurance served a search warrant on the lessee of the property. Kubo said officials are looking for 55-gallon drums containing chemicals along with large amounts of gasoline, hundreds of gallons of waste oil, hundreds of tires, a large number of thrown-away car batteries — still containing acid — and used automobile antifreeze liquid containing lead.

The holes in which they are believed buried are very deep, "which shows a calculated attempt to hide (the items)," Kubo said.

"These type of materials also have the potential of ... damaging our ocean, our fish population and our reefs. Finally, these materials also have the potential of seeping downward into our precious drinking water and possibly poisoning our people," Kubo said.

The site poses no immediate public health threat, said Nick Torres, special agent in charge of the EPA regional Criminal Investigation Division based in San Francisco.

The EPA is investigating several other illegal dumps in West O'ahu as part of Operation E Ola Pono 2008, a federal initiative to enforce EPA laws in Hawai'i.

"Through this initiative, it is hoped that more people will be held accountable for their wrongful actions when it comes to abusing our air, our land, and our waters," Kubo said.

Federal authorities heard about the illegal dumping while investigating drug activity at the Hakimo property, an agricultural-zoned lot used for a hodgepodge of purposes including animal boarding and auto-body shops. Yesterday's raid capped an investigation which began about 18 months ago.

The property is home to sheds, utility structures, buildings, buses, dozens of cars and trucks, and numerous dogs and other animals.

Throughout the day, armed federal and state agents stood by the chainlink fence entrance to the Hakimo Road property and kept people out. Occasionally people dropped by to say they had come to pick up animals.

Several Hawaiian Humane Society trucks were stationed inside the property and society personnel either brought the animals to the entrance, or allowed people inside to retrieve their animals.

One man left with a half-dozen or more exotic birds; another came to pick up several dogs he kept on the property. Still another told agents he was there to get his horse.

Charlene Concepcion, 20, who has lived in a bus on the property for about a month, said when the raid began, she went outside to see what was going on.

"We were in fright," said Concepcion, who said she heard loud noises and gunfire. "We heard what sound like one fight, so I come running out of my bus, like, 'What's going on?' and I've got, like, three guns pointing at me to sit. I wasn't even dressed completely, and they just made me sit. They wouldn't, like, let us move or anything."

Concepcion said she and 10 others live on the property. She said her family leases some of the land to operate A&E Services, which delivers food waste to area pig farmers. Concepcion, who works for the company, said her family is not involved in illegal activity of any kind. But she said the federal agents told her the raid happened because of illegal dumping taking place on the property. She described those living on the property as normal, decent folks.

Authorities are expected to continue digging for evidence on the property, possibly through tomorrow.

Kubo said FBI, Drug Enforcement Administration, Immigration & Customs Enforcement, Coast Guard Investigative Services, U.S. Fish and Wildlife Investigative Service, and state Public Safety personnel are assisting the DEA.