When excavation begins, topsoil is stockpiled to resurface and provide nutrient rich soil for grass seed to take root in.
All sediment must be excavated past the location of the failure and any water seams found in the substrate. Excavation is completed when all soil surrounding the sinkhole is compacted and stable.
The above picture illustrates a method of slope rehabilitation which involves disking the ground to a depth that will bring up darker soil and rake the surface smooth. Once the slope has been regraded, grass seed and fertilizer is spread and raked under the surface. By raking in the seed, birds have a more difficult time eating the seeds. It is recommended to lay erosion blanketing to hold soil in place through any rain events during germination. Overall this method is more effective than hydroseeding and significantly less expensive.
Stabilized sand is used to fill the excavated hole and is compacted gradually to ensure that the sinkhole does not form with normal rainfall.
Detention basins that are not properly constructed with a suitable topsoil layer will inevitably lose ground ground cover in southern regions where nutrient poor clay makes up most of the soil composition. Over time, the lack of vegetation allows rain water to erode the banks leaving deep trenches that become difficult to maintain.
PSL provides affordable land clearing services using methods that reduce unwanted lingering root material and excess construction phase stormwater pollution.
Slope Repairs and Stabilization
Our staff has an in depth knowledge of not only the causes of sinkholes and slope failures, but the proper methods to fix them. Below is a series of pictures before during and after the formation of a sinkhole repaired by PSL.
Clearing and Grubbing
Above is a 3 foot wide sinkhole in the middle of an access easement that formed as a result of natural sediment compaction as pre-development root material decomposes beneath the surface. These sinkholes can be dangerous as they are known to grow rather quickly and unexpectedly.