Location:

Sierra Mining and Crushing Company LLC
Composting area of manufactured product
8665 South Alvernon Way
Tucson, Arizona 85756

Discovery Date: 

December 2010

Contaminants of Concern (COCs):

Emissions resulting from smoldering compost pile

Affected Media:

• Soil
• Air

What Are My Health Risks?

For Soil | There is little to no health risk unless there is contact with skin or ingestion of contaminated soil.

Site Summary:

This facility practices the crushing, mining, shredding and sifting of received gravel, asphalt, wood and green waste which are processed over time.  Resulting products consist of a variety of landscape materials including gravel, crushed concrete, topsoil, ornamental rock, solid amendments, fuel for biomass power plants and horse bedding. In June 2010, a fire occurred at a 3.62-acre compost pile consisting of wood and green waste located on the southeast portion of the property. To address the fire, the entire burn pile was covered with dirt and topsoil. To date, the covered wood and green waste continues to smolder and has occasional flare-ups from venting areas and subsurface pressure. The site has managed to decrease the compost pile to 2.5 acres and continues to remove and recycle usable materials from the pile and manage flare-ups.

Corrective Actions:

• Complaint response inspection completed in November 8, 2010 in response to the fire.
• Consent order signed March 25, 2014, containing an approved plan to remove and dispose of materials to minimize fire flare ups and remediate entire compost pile.
• Conducting and monitoring the soil-covered pile of vegetative and wood waste and nuisances to assess temperature and evidence of potential fire areas.
• Submitting quarterly status and monitoring reports on quantities of waste removed and disposed from pile and separated waste for recycling.
• Documenting timeframes of fires and flare-up occurrences and management activities of the active pile.