New questions have been raised about a toxic cleanup in Middlesex County that has been the subject of a Kane In Your Corner investigation. Newly released documents raise doubts about the legitimacy of an engineering report used to justify the project.

Workers are trucking in tons of soil to cap cyanide-tainted sludge at the old American Cyanamid plant in Carteret. It is a project some have long contended could do more harm than good.

As Kane In Your Corner reported in 2013, the Christie administration pushed the project forward over the objections of some New Jersey Department of Environmental Protection staffers who warned that the weight of the soil cap could force cyanide into the nearby Rahway River. The NJDEP admits some staff members initially opposed the plan, but says those staff members eventually changed their minds.

At issue is a geotechnical engineering report that the property owners and their licensed site remediation professional, Al Free, provided in defense of the project. Free gave NJDEP the report in 2013 on the condition that it not be released under the Open Public Records Act. He provided a different version of the report for public release. Both Free and NJDEP insisted that the two reports were identical, except some company trade secrets were redacted in the public version.

But the reports aren't the same.

In the NJDEP version, which is just now being made public, several safeguards are included to prevent the kind of structural failure that environmentalists are worried about. For example, one section reads "No heavy equipment shall be applied within 50 feet of the cap edge." In the public version, that section is missing.

The project is also supposed to unfold in stages, with waiting periods in between. The previously unreleased NJDEP report estimates the waiting periods to be 50 days. In the public version, the waiting periods are shorter, just 38 days.

Environmentalists say those changes and others seem to have one thing in common. "All the details about how to protect the site from being overloaded ... have just been eliminated," says Marian Glenn, president of the Rahway River Watershed Association.

Free insists the discrepancies are because of a clerical error. He says his office accidentally used an unfinished draft of the report for the public version, while giving the final report to NJDEP. "The [public version] was clearly a draft since it was unsigned," he says. Both reports, however, are clearly marked "final," and both bear the same date. There is nothing to indicate that either one is a draft.

Free also argues that none of the discrepancies had any impact on the project because the report NJDEP reviewed was correct. But environmentalists say the public also had a right to know all the safety measures in order to better monitor whether those measures were being followed.

And if this was a clerical mistake, it happened more than once. In 2014, a year after the first two reports were released, the U.S. Environmental Protection Agency asked for a copy of the report. The version it received doesn't match either of the other two. Free says once again, a clerical error is to blame, and that a revised version of the unfinished draft was sent by mistake.

"We're not even sure which report we should be looking at," says Emile DeVito of the New Jersey Conservation Foundation. He's calling on the U.S. EPA and state DEP to halt the project until a full investigation can be conducted.

The NJDEP says it has no intention of doing that. A spokesman says the agency believes the explanation that a clerical error is to blame, but the U.S. EPA isn't so sure. A spokesman says that agency had no idea it had received a report that was different from the others until Kane In Your Corner brought it to his attention. He says the agency will add that to the list of things it is investigating.