Stone Tracking Pad
GeneralA stone tracking pad is designed to limit the amount of sediment that is transported from a site by vehicles. Stone tracking pads remove sediment from the tires of vehicles by allowing the tires to sink in to the stone base slightly. This action, combined with the rolling motion of the tires, acts to knock loose the majority of sediment from a vehicle’s tires.
Stone tracking pads are generally used on construction sites at any point of entry and exit and must be installed as soon as the drive area has been graded.
- Effective for erosion and sediment control
- Prevents tracking of sediment onto public roads
- May require extensive maintenance if used on muddy sites
DesignStone tracking pads should be at least 24 feet wide and 50 feet long, and constructed of 3-6 inch washed stone with a depth of at least 12 inches. On sites with clay soils, stone tracking pads must be underlain with a geotextile liner to prevent the stone from sinking into the soil.
Surface water must be prevented from passing through the tracking pad, as even low flows may dislodge sediment and carry it off site. Flows may be diverted away from tracking pads or conveyed under and around them by using a variety of practices, such as culverts, water bars, or other similar practices.
Wash RacksOn sites with heavy traffic or in muddy conditions, a wash rack may be required. Wash racks, which consist of a heavy-duty grate and a water collection system, remove sediment buildup from tires with water and increase the efficiency and lifespan of stone tracking pads by preventing sediment buildup.
The water used must be collected on site and diverted to a settling basin, where suspended soil particles can be deposited before the water is allowed to leave the site.
- A stone tracking pad should be installed as soon as the drive area has been graded
- Stone tracking pad should be removed from the site after construction is complete and the site has been stabilized
- Additional stone is required if existing stone becomes buried or if sediment is not being removed effectively from tires
- Sediment that is tracked onto the roadway must be removed immediately
- Tracking pads may require periodic cleaning to maintain the effectiveness of the practice, which may include the removal and re-installation of the stone
Method to Determine Practice EfficiencyA stone tracking pad reduces the amount of sediment that is removed from the site by construction vehicles and is a required practice on every construction site. As a result, no efficiency is given for this practice.