Colorado’s state-run Obamacare health insurance exchange failed to check many applicants’ eligibility, according to a new report from the U.S. Health and Human Services Office of Inspector General.

The report comes just months after the Obamacare program’s health care co-op closed its doors in October, leaving 83,000 people looking for new insurance coverage.

Connect for Health Colorado didn’t always verify applicants’ eligibility or have “effective policies and procedures to ensure that inconsistencies in eligibility data were always resolved,” according to the IG. Colorado didn’t verify the Social Security number, citizenship or incarceration status, residency or family size of applicants who applied for insurance but not financial assistance.

About 40 percent of Coloradans with health insurance through the state marketplace were in the failed co-op, Colorado Health-Op, according to the Colorado Independent. The aborted co-ops have cost taxpayers at least $876 million so far, and more failures are likely on the way, a spokesman for HHS told The Daily Caller News Foundation in September.

The IG is auditing all state-run exchanges’ eligibility verification practices and program expenses. But the IG only examined eligibility procedures in Colorado, rather than listing examples of waste, fraud or abuse.

The Colorado exchange’s problems could be worse than the IG knows.

“Because our review was designed to provide only reasonable assurance that the internal controls we reviewed were effective, it would not necessarily have detected all internal control deficiencies,” the IG said.

The IG only reviewed 45 applicants, selected at random, to produce the report.

The IG told the Colorado marketplace to clean up its eligibility process and eliminate ineligible applicants better. Connect for Health Colorado General Counsel Alan Schmitz agreed with the IG’s findings in a Sept. 15 letter, and said the co-op is working on all those recommendations. That was before Colorado Health-Op closed its doors.

Connect for Health Colorado could not be reached for comment Wednesday.

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