(TNND) — Misdated veterans' disability compensation awards for the PACT Act resulted in at least $6.8 million in improper payments, the Department of Veterans Affairs' watchdog said this week.

The VA’s Office of Inspector General reviewed a sample of 100 PACT Act-related claims completed in the first year of the law, which VA has said is perhaps the largest health care and benefits expansion in its history.

From that sample, the OIG estimated that incorrect effective dates were assigned for about 31,400 of 131,000 claims, or about a quarter of the claims.

Another 2,300 or so claims had the potential to affect veterans’ benefits by an unknown monetary amount, an OIG report said.

And the OIG warned that if VA continues to make the same mistakes, it risks issuing millions of dollars more in improper disability benefit payments.

President Joe Biden signed the PACT Act into law in August 2022, expanding health care to veterans exposed to toxins during their service.

Burn pits used at U.S. bases during the wars in Iraq and Afghanistan were blamed for illnesses, including cancers, and brought this issue to the forefront. But pre-9/11 veterans who suffered toxic exposure are also covered under the PACT Act.

The new law brought a lot more veterans to VA.

Nearly 740,000 veterans enrolled in VA health care during the first two years of the PACT Act. That was a 33% increase over the previous two-year period.

And VA said last month that it had completed over 2.1 million PACT Act-related claims.

Republican Rep. Mike Bost, the chairman of the House Committee on Veterans’ Affairs, told The National News Desk in a statement that the Biden administration failed to prepare VA claims processors for the PACT Act.

Bost said the previous administration "botched" the PACT Act rollout.

"These incorrect dates have caused millions of dollars in improper benefits payments to veterans," Bost said in the statement. "It's clear that VA needs to better train its employees. Veterans shouldn’t have to deal with sloppy work from VA, and Americans shouldn't have to shoulder the burden of VA's wasted taxpayer funds."

Bost said a House veterans’ subcommittee will hold a hearing about the issues highlighted in the OIG report.

Jim Lorraine, the president and CEO of America’s Warrior Partnership, an advocacy organization for veterans, said rolling out the PACT Act was a massive undertaking for VA.

"Absolutely. And not only was it a massive undertaking, if you recall in the legislation, there was a rollout schedule. They were going to eat the elephant one bite at a time. And President Biden, when he announced it, said ... everybody can apply, all at once," Lorraine said.

The PACT Act "was definitely needed," he said.

But the guidelines are complex.

And he recalled many people within the veteran community questioned VA’s ability to handle the influx of claims in the early days of the law.

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The PACT Act expanded the "presumptive conditions" that qualify a veteran for benefits based on their exposure. They don’t have to prove that their service caused the condition.

A variety of cancers and other illnesses, including post-service asthma, bronchitis and emphysema, are now presumptive conditions from toxic exposure.

The OIG report included recommendations for VA staff to prevent additional mistakes with dates of PACT Act claims.

Among the recommendations, OIG suggested officials create a job aid for claims processors on how to determine the correct effective date for PACT Act-related claims.

The watchdog suggested removing an outdated effective date builder from the VBA’s internal job aids page.

And it suggested correcting all processing errors on cases identified by the review team, with a report back to the OIG.