Gravel borrow is a granular, sandy material, with the largest particle being 7/8”. Because gravel borrow is screened, and not crushed, the particles are round, and for the most part do not have fractured faces. Gravel borrow compacts well and is an excellent structural fill material.
This product is used as a road or driveway base, as it compacts well. The large particle size makes 3” minus an excellent material to build up low areas, or to bridge muddy or unstable subgrade.
1 ¼” minus crushed basalt is also known as Crushed Surfacing Base Course (CSBC). Similar to 5/8” minus CSTC, this material is made to Washington State DOT specifications. It is commonly used under 5/8” minus as a base material where more depth is needed to build up a grade or driveway/road bed. Like 5/8” minus, 1 ¼” minus compacts well and creates a hard, stable surface.
This material is made and screened in the same process as 5/8” minus crushed basalt, but is made from recycled concrete. It performs similarly to crushed basalt, and is made to Washington State DOT specifications.
Crushed asphalt is made from recycled asphalt, and is crushed using the same process as 5/8” minus or 1 ¼” minus basalt. Crushed asphalt is commonly used to surface driveways or parking areas, and works well for that purpose. Because the oils in the asphalt help the material bind together, this product typically has a denser and more durable surface than crushed rock.
5/8” minus crushed basalt, commonly called Crushed Surfacing Top Course (CSTC), is a crushed and screened basalt rock. This material is manufactured to Washington State Dept of Transportation specifications and is designed to compact well and create a hard, stable surface. 5/8” minus is typically used as the surfacing layer for driveways and roadways, and also as base material under concrete slabs or foundations.