The projects we work on have one thing in common: they’re doing their best to make environmentally friendly decisions. A big mistake we’re seeing on site is how soil is being stockpiled. This step has ramifications on the entire recycling process.
What usually happens: soil is stocked in 5-10 metre high piles, which have been heavily compacted – sucking the life out of the soil. The piles are often placed at a low point on site, creating a moat surrounding the material.
What should happen: stockpiles should be no higher than 2ish metres, with a flat top, and located in a spot that allows surface water to run past the stockpile
Why?
- Stockpiling in this way allows the soil to breath, keeping the it healthy and alive
- Soil is made up of 45% minerals, 5% organic matter, 25% water and 25% air; if the soil is compacted the air goes and the soil suffers
- It avoids water saturation in and around the material
- Finally, it avoids erosion and allows water to naturally flow through the soil
Happy soil = happy project.
Other best practice rules for soil stockpiling include…
- Don’t drive on the stockpiles!
- They can be as long as the space allows
- If topsoil stockpiles are to be in place longer than a month, sow with a seasonally appropriate annual cover crop (as per EPA guidelines for major construction sites)
- Locate stockpiles 5 metres or more from concentrated water flows (including drainage lines and roadways)
- Locate stockpiles away from and upslope of works areas including refuelling operations
- Use diversion drains upslope from stockpile
- Protect downslope sediment loss using sediment control structures (silt fencing or other approved method)
- Stockpile locations are preferred to have less than 10% slope
- Locate stockpiles outside the designated Tree Preservation Zones (TPZ) or more than 8 metres away from any retained trees
- Protect stockpiles from waste and rubbish dumping and encroachment of works
Who knew so much thought needed to go into piles of dirt?
Need a hand with your soil management? Get in touch.
