The State Department of Toxic Substance Control (DTSC) admits it failed to collect nearly $185 million from polluting businesses, essentially passing those costs onto California taxpayers.

Earlier this year in an NBC4 investigation, insiders with the DTSC said the agency often failed to take significant action against business and industry that didn’t clean up contamination.

Now the DTSC admission indicates when it did move in to deal with cleanup, it frequently let the polluting businesses off the hook and stuck taxpayers with the bill.

DTSC Director Debbie Raphael said her department only “used state funds where it had to act quickly, where there was a health and safety issue and where there was not an apparent or willing responsible party who was able to step up to the plate.”

But she said her department historically had no real process to then turn around and collect that money from the polluters.

“It is disappointing that over 26 years, no one put together a system to make sure we accurately tracked and billed those costs,” DTSC spokesman Jim Marxen said.

Critics of the DTSC say the sudden admission isn’t enough.

“This is just the tip of the iceberg,” said Liza Tucker, of the group Consumer Watchdog.

She said she’s been stymied in her attempts to get records on how much money has gone uncollected, and she is calling for a State Audit of the Department of Toxic Substance Control.

“I’m asking for a full-fledged independent financial audit by the California state auditor,” Tucker said. “I think what we’re going to see is more extensive historical fiscal mismanagement. I think it’s time for heads to roll at the DTSC.”

It was three months ago that whistleblowers inside of DTSC told NBC4 their agency is far too lenient on polluters.

One insider, who spoke on the condition of anonymity, said, “If we were doing what we were supposed to be doing, we would be doing much more enforcement and we wouldn’t let some of these industries get away literally with murder.”

Officials with DTSC said they aggressively enforce state regulations. And they promise to straighten out historic problems they say have led to failures to hold polluters financially responsible for cleaning up contamination.

“I am committed to making every effort to collect past costs and create an internal system that ensures this kind of backlog never happens again,” Raphael said.