07/29/2009 Env Bd Packet - Laserfiche WebLink

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• 4_ fir} -c (4(1,t 2 wJ / 0 RMP -3 CAPROC Issues For Eaglebrook Church Parking Lot Expansion Project 2009 8(c) In addition to the BMPs required under 8(b), volume control measures are required reducing runoff by at least the volume from 0.5- inches of rainfall over impervious surfaces on the site (0.5 -inch multiplied by impervious area). Volume reduction required under this paragraph may be achieved only by the following measures: Reestablishment of Effectively Drained Wetlands and Floodplain Meadows Upland Restoration /Conservation, Restoration of Degraded Wetlands, Impervious Disconnection, Soil Amendments/Tilling. (See Accompanying table). 8(b) Better Site Design principles will be incorporated and water quantity BMPs (as defined in this Rule) must be incorporated to the following standards: (i) BMP volume must retain the one -year event by providing at least the volume equal to the runoff from a 2.3 -inch, 24 -hour storm over the tributary area within the site under proposed conditions. (1) Infiltration BMPs (see District BMP standard plates and design criteria) are to be incorporated in areas with A & B • hydrologic soil groups. Stormwater from impervious surfaces other than rooftops must be pretreated before discharge to infiltration BMPs, to remove sediment and floatables, or other materials that would restrict the BMP's capacity or contaminate ground water. (2) In the following areas, the volume required by paragraph 8(b)(i) is to be provided by bio- filtration features or two -cell wetland treatment systems (see District standard plates and design criteria): (b) Better Site Design principles will be incorporated and water quantity BMPs (as defined in this Rule) must be incorporated to the following standards: (i) BMP volume must retain the one -year event by providing at least the volume equal to the runoff from a 2.3 -inch, 24 -hour storm over the tributary area within the site under proposed conditions. (1) Infiltration BMPs (see District BMP standard plates and design criteria) are to be incorporated in areas with A & B hydrologic soil groups. Stormwater from impervious surfaces other than rooftops must be pretreated before discharge to infiltration BMPs, to remove sediment and floatables, or other materials that would restrict the BMP's capacity or contaminate ground water. (2) In the following areas, the volume required by paragraph • 8(b)(i) is to be provided by bio- filtration features or two -cell wetland treatment systems (see District standard plates and