DENVER — Colorado lawmakers are asking the Colorado Department of Public Health and Environment for an investigation into the ash incident at Suncor, an oil refinery plant in Commerce City.

Earlier in the week, white, yellowish ash dropped from the sky in Commerce City. In response, Suncor offered free car washes.

“Myself and a few other lawmakers wrote a letter to the Department asking them to launch their own investigation into what happened recently at Suncor,” Democratic state Sen. Dominick Moreno said Friday. Moreno represents Commerce City.

While CDPHE has committed to the senator to conduct air monitoring tests, Moreno said believes more must be done.

“CDPHE doesn’t actually have complete control over emissions at different facilities,” Moreno said — hinting at potential new legislation.

Suncor has called the incident an “operation upset” and emphasized the ash was not hazardous. Suncor referred to the ash as a catalyst from a clay-like material. The name of the actual chemical involved has not been released.

“Until we know the actual name of the chemical, we can’t understand the safety impacts,” said Ean Tafoya, with the Colorado Latino Forum.

Tafoya has called for more oversight following the event.

“I think it is a slap in the face to our community,” Tafoya said.

Suncor told FOX31 they will continue to work with local and state governments.