FAQ

AGGREGATE PRODUCTION

What aggregates are mined at the facility?
Natural materials like rock, gravel, sand and dirt are mined and used to vital construction materials that go into roads, bridges, homes, hospitals, schools and office buildings that have made Maricopa County what it is today.

How are the materials mined on the site?
Loose rock, gravel, sand and dirt are extracted from the ground at the Val Vista facility using a dragline that breaks the material loose. A loader transfers the material to a primary crusher, which breaks the rocks into smaller ones. The aggregates are then transported via a conveyor to the plant where the rock is crushed, sized and sorted.

Where do the finished products go after that?
Most of the finished material is used for the production of hot mix asphalt (HMA) pavement or concrete.

HOT MIX ASPHALT (HMA) PRODUCTION:

What ingredients are used to make asphalt?
Asphalt pavement is composed of 95 percent aggregates (stone, sand and gravel) and 5 percent asphalt cement.

How is hot mix asphalt made?
Aggregates are dried and heated in a drum before being coated with asphalt cement, which acts as the “glue.” The product is taken by truck to a job site.

What is the health impact?
As an industry leader in protecting the health of our employees, our operations are safe for our employees inside the gate and safe for our neighbors beyond. Hot mix asphalt facilities are heavily regulated by federal and state agencies and are not considered major sources of air pollution, according to the U.S. EPA. Val Vista has been in compliance with all laws and regulations and as such is considered by local, state and federal regulatory officials to be protective of public health and safety.

Can asphalt be reused?
Asphalt is entirely recyclable and reused more often than newspapers, aluminum cans and glass. Approximately 80 percent of asphalt pavement that is removed is recycled annually.