IRWINDALE ( — A slow-burning fire continued to burn Wednesday morning in a stories-high pile of compost in Irwindale.

It was first reported around 7:20 p.m. Tuesday at Cal Blend Soils in the 1200 block of East Arrow Highway, according to the Los Angeles County Fire Department.

The blaze has prompted authorities to close the nearby Arrow Highway onramp to the northbound 605 Freeway. It’s unclear when it will reopen.

Meanwhile, crews are turning over compost to try and get to the flames deep-seated within the pile.

Residents across the San Gabriel Valley say they can smell the smoke.