Loading...
HomeMy WebLinkAboutWPO201200016 Review Comments Erosion Control Plan 2012-04-23ALg�,�� �'IRGINZ� COUNTY OF ALBEMARLE Department of Community Development 401 McIntire Road Charlottesville, Virginia 22902 -4596 Phone (434) 296 -5832 Fax (434) 972 -4126 Project: Kroger Fuel Center Erosion and Sediment Control Plan; WPO- 2012 -00016 Plan preparer: Robinson LOIA Roof Replacement PC Owner or rep.: AEW SCT Rio Hill LLC c/o Hart Realty Advisors Inc. Date received: 8 February 2012 (Rev. 1) 10 April 2012 Date of Comment: 27 February 2012 (Rev. 1) 23 April 2012 Engineer: Phil Custer The first revision to the erosion and sediment control plan for the Kroger Fuel Center (WPO- 2012 - 00016), received on 10 April 2012, has been reviewed. The plan can be approved after the following comments have been addressed: 1. The proposed grading plan calls for several weeks of earthwork. Considering this and the large drainage area to inlet 7 during the initial phases of construction, sediment trap inlet protection must be utilized on this structure. Please show proposed trap grading on sheet C -4 with a top contour of 504.44, a bottom contour of 502.44, and a calculation showing the necessary trap volume. Because of the proximity to construction traffic, sizing the trap for the full pre - development watershed, considering the full 134 cy /acre and maximum 2ft depth standards, may be problematic. To reduce the required trap size, curb inlet 1, adjacent curbing, and the downstream drainage should be constructed before the existing asphalt pavement is demolished. Once this system is setup to bypass the clean water around the construction site, the trap on structure 7 and the rest of the project can move forward. Also, county engineering would look favorably on granting a variance of the 134cy /acre volume standard, allowing a wet volume equal to 67cy /acre, as long as block and gravel inlet protection is used above the wet pond volume. A variance request should be written in a word document or email to the county engineer. All variance requests require a fee of $150 in order to be officially reviewed. (Rev. 1) The variation requested by the applicant for a reduction in sediment trap size on grate inlet #7 is hereby conditionally approved. Please modify the plan in the following manner to meet the conditions of the approval. a. Please provide a note adjacent to curb inlet #1 stating that the "demolition of pavement downhill of this new curb shall not occur until this curb, inlet, and downstream drainage structures have been installed to ensure that excess offsite runoff does not travel through the disturbed site." b. Please correct the discrepancy between the drainage inlet map, which shows 0.57acres to DI #7, and the ESC plan sheet, which shows 0.50acres. If the trap must be increased in size, please do so. Otherwise, please provide an updated drainage inlet map. c. Please include Plate 3.07 -3 from VESCH on the ESC detail page and refer to it specifically at Drop Inlet #7. Inlet protection around Drop Inlet #7 will require that a slope from the top of the inlet to the bottom of the facility be shown. The structure cannot be freestanding. If this was the applicant's intention, please provide a unique detail. Because of the slope from the top of the inlet to the bottom of the trap, the footprint may need to expand in another direction to maintain the current volume. 2. On the existing parking lot curb line south of the gas canopy, please provide a note stating that if existing curb is to be demolished, the contractor shall replace with a diversion dike directing runoff to one of the eastern inlet protections. (Rev. 1) Comment has been addressed. 3. Please provide Dust Control symbols (DC) on the plan. (Rev. 1) Comment has been addressed. 4. Please replace the state's CE detail with the county's Paved Wash Rack detail located on page 28 of 35 in the latest edition of the County's Design Manual. For the current location, please provide a note that states that existing pavement will be used and maintained as a construction entrance until approved by the county Erosion and Sediment Control Inspector. (Rev. 1) Please provide a (CE) symbol at the location of the paved area to be used as a construction entrance. 5. At the south and southeast entrances to the site, please provide a mountable asphalt berm/RWD to direct construction runoff to the inlet protection measures within the site on structures 5 and 7. (Rev. 1) Comment has been addressed. 6. Please replace all straw bale barriers with silt fence and remove the detail from the set. (Rev. 1) Comment has been addressed. 7. Before a grading permit can be issued by the county, the applicant will need to pay the first year permit and inspection fee and post the erosion and sediment control bond. To receive a ESC bond, please provide a completed Bond Estimate Request Form to the county engineer once the ESC plan has been approved. (Rev. l) A bond request form has been received by the county. A bond amount will be provided to the applicant soon. File: E2_ecp_PBC _ wpo- 2012 -00016 Kroger Fuel Center.doc