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Storm Water
 Stormwater Management rules allow for the construction of alternative BMPs that meet the pollutant removal design statndard of 85% removal of total suspended solids (TSS). Surface coal mining operations nationwide permit #21 requires that all earthwork operation shall be carried out so that sediment runoff and soil erosion to waters of the state are controlled and minimized.
The storm water BMPs that can be utilized for various industries and municipalities are given as presented below.
|
BMP |
Assumed TSS Removal |
|
Wet Detention Basins |
85% |
|
Extended Detention Wetlands |
85% |
|
Pocket Wetlands |
35% |
|
Sand Filters |
85% |
|
Bioretention Area |
85% |
|
Grassed Swales |
35% |
|
Extended Dry Detention |
50% |
|
Filter Strips |
25%-40% |
|
Infiltration Devices |
85% |
Meade Gunnell utilizes SEDCAD computer model techniques for sediment removals to estimate TSS removal. Therefore, our storm water designs can be customized even beyond the BMPs noted above.
One alternative to BMP design is a Biorention Area (sometimes referred to as Rain Gardens) which can be considered as an alternate retention facilities for treatment of low run-off flow rates. Typically they are designed to mimic forested BMPs that naturally control hydrology through infiltration and evapotranspiration. Attached is a typical plan and design information for bioretention water quality treatment and Skimmer Systems that could be used in the mining industry. | 
