POMPTON LAKES — Fearing that their basements could be flooded with dangerous chemicals, many residents plan to speak out Tuesday night against a controversial plan by DuPont to pump clean water into a polluted aquifer that has sat for decades under a neighborhood with high cancer rates.

The public hearing, held by the state Department of Environmental Protection, will take place at St. Mary's Church's Carnavale Center at 10 Lenox Ave. from 7 to 9 p.m.

Among the concerns is whether pumping water into the ground will flush cancer-causing solvents into the basements of some of the 450 homes above the toxic plume. The pollution originates from a now-shuttered DuPont munitions plant adjacent to the neighborhood.

The plan, called "hydraulic surcharging," is considered a pilot test and has not been conducted at other contaminated sites in New Jersey, a DEP spokesman said. It was proposed this spring by DuPont spinoff company Chemours and needs final approval from the DEP to obtain permits. Residents have been lobbying for months for a public hearing.

"We don't want to be their guinea pigs," said Lisa Riggiola, a longtime advocate who until recently lived in the neighborhood. "They keep coming up with these pilot studies, these gimmicks. We are tired and want a full cleanup."

The pollution dates back more than a century to when DuPont acquired an explosives manufacturing facility in 1902 and 1908 on 570 acres near the Wanaque River. The company made and tested blasting caps and other explosive devices onsite until the plant closed in 1994.

The groundwater under about 450 homes is contaminated primarily with PCE and TCE, cancer-causing solvents used by DuPont to clean equipment. The chemicals already seep into many basements by vaporizing into gas. DuPont has installed ventilation systems at 333 homes.

The pollution has stigmatized the neighborhood, leaving some unable to sell their houses and many worried about their health.

In 2009, the state Health Department found significantly elevated levels of kidney cancer and non-Hodgkin's lymphoma among residents of the affected neighborhood — cancers that have been linked in lab studies to TCE and PCE. The state did not definitively link the elevated cancer rates to the solvents in the groundwater, but did not rule that out as a cause. Many residents want DuPont to buy their homes so they can move.

Residents, many of whom have sued DuPont in one of three class-action lawsuits, have long been skeptical of the cleanup plans offered by the company and overseen by the DEP and U.S. Environmental Protection Agency. They say DuPont has moved its cleanup operations at a glacial pace over 35 years.

The plan calls for workers to install a horizontal pipe about 20 to 25 feet deep and running for about 600 feet along a railroad bed behind homes along Barbara Drive, just south of the DuPont property. Clean water will be pumped through the perforated pipe, theoretically diluting the pollution in the groundwater.

The DEP and EPA are supportive of the project based on field tests.

"DEP/EPA saw an improvement downgradient of the existing system discharge," said Larry Hajna, a DEP spokesman.

In a 54-page report filed with the DEP in May, Chemours engineers said the hydraulic surcharging project would not cause basement flooding. They said they have had no problems with a pump-and-treat system installed at the plant in 1998 that extracts 8 million gallons of polluted water a month from the ground, treats it at the surface and pumps it back into the aquifer.

"Based on 18 years of operating the existing [pump-and-treat] system and the modeling of the horizontal well, there should be no issues with regards to potential flooding of basements," the report says.

But some residents said they have spoken with a number of insurance companies that would not issue policies to cover damages that might occur from this sort of project. They say there is no contingency plan if there are problems like basement flooding.

"There's no guarantee it will actually work, and it puts us all at risk," said a flier sent to residents this month by the advocacy group Citizens For a Clean Pompton Lakes.

"We’ve been speaking to experts around the country who know this stuff," Riggiola said. "They don't like this. They say the proper modeling has not been done.”

DuPont did a pilot test of a different cleanup method in 2011 and 2012, when it injected soybean oil and then sodium lactate into the soil as a food source to stimulate growth of naturally occurring microbes that could break down the PCE and TCE into non-harmful substances. The results were disappointing because the groundwater did not distribute the food evenly or quickly through the plume.