HomeMy WebLinkAboutWPO201600072 Correspondence WPO VSMP 2020-12-23
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December 23, 2020
RE: WPO201600072 - Woolen Mills Light Industrial Amendment 4
Dear David:
Below are responses to the letter addressed November 3, 2020.
General
1. Obtain a Floodplain Development Permit for the additional disturbance to floodplain proposed
prior to this amendment approval.
FLOODPLAIN DEVELOPMENT PERMIT HAS BEEN SUBMITTED.
2. Separate building permit required for walls. Contact building department.
COMMENT NOTED.
Stormwater Pollution Prevention Plan
1. LOD is 6.33ac. The registration statement will need to be revised to that amount. DEQ permit
modification fee. Grading permit fee?
LOD HAS BEEN CORRECTED TO SHOW 6.33AC EVERYWHERE.
2. Update the SWPPP upon plan approval.
COMMENT NOTED.
Pollution Prevention Plan
1. Update the PPP upon plan approval.
COMMENT NOTED.
Stormwater Management Plan (SWMP)
1. Sheet 12 (Storm Profiles)
a. Please correct the length & slope of Pipe 101 shown in the profiles. They don’t match the
values shown on Sheet 14.
C-612: TABLE HAS BEEN CORRECTED TO MATCH PROFILE AND DESIGN
CONDITIONS.
b. Provide 2.0’ or ½ D minimum cover (whichever is greater). Ensure cover is adequate over
pipes.
C-612: COVER HAS BEEN ADJUSTED OVER CERTAIN PIPES.
2. Sheet 14
a. Show the design storm W.S.E. in the SWM-2 detail.
C-612: 100-YR STORM IS SHOWN.
b. Show the 100-yr W.S.E. in the SWM-1 detail.
NOT REQUIRED SINCE THE BASIN IS IN THE FLOOD PLAIN.
440 Premier Circle, Suite 200
Charlottesville, VA 22901
Phone: 434.882.0121
www.meridianwbe.com
Engineering • Surveying • Planning
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3. SWM-1: Show emergency spillway has been adequately designed. Due to site conditions (Dry pond
in the flood plain) provide that the riser structure contain the emergency spillway.
EMERGENCY SPILLWAY IS ADEQUATELY DESIGNED.
4. ELS to conserved open space [VADEQ BMP Spec#2]: Provide design that will reduce disturbance,
need to curve/redirect flow.
ELS HAS BEEN REMOVED.
5. Provide required ELS length Calculation. I measure the length to be 76’
6. ELS HAS BEEN REMOVED.
7. Show Conserved Open Space area in an easement. Currently shown as 50x50 area. The width
should be at least the same length as the ELS.
8. ELS HAS BEEN REMOVED.
9. Provide proof of vegetative cover in the conserved Open Space easement.
ELS HAS BEEN REMOVED.
10. Provide ponding reports on SWM-1 & SWM-2 facilities and list the outlet controls (weir & orifice)
discharge rates.
C-622: PONDING REPORTS HAVE BEEN ADDED TO THE PLANS.
11. Sheet 18: VRRM – Overall site area is 14.06ac. 6.33 ac is listed as disturbed on current E&SC plan;
up from 5.71 on the original design plan. 7.39ac disturbance is listed on VRMM. ? No new area
has been added or subtracted from the original site area, correct? I believe you can just modify the
original VRMM and come up with the new nutrient load requirements.
C-623: VRRM HAS BEEN REVISED.
12. Please submit VRRM excel file (email is fine).
VRRM SPREADSHEET HAS BEEN EMAILED.
13. Provide the amount of Forest/Open Space easement area to be vacated.
FOREST/OPEN SPACE AREAS TO BE VACATED ARE SHOWN ON EASEMENT
PLAT.
14. Provide letter of availability from nutrient bank provider if additional nutrient credits are required.
C-623: LETTER OF AVAILAILITY FOR 2.66 LBS/YR HAS BEEN ADDED.
15. Record deed & plat for the new/modified SWM easements.
INFORMATION WILL BE ADDED ONCE PLAT HAS BEEN APPROVED AND
RECORDED.
Erosion and Sediment Control Plan
1. Cover sheet: add note, “Areas of Forest/Open Space shown on Sheets 2 & 3 are to be demarcated
(fenced off) prior to land disturbance”.
C-500: NOTED HAS BEEN ADDED.
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2. Sheet 2-7: Areas of Forest/Open Space (F/OS) in easements are to be protected. Correct the sheets
to show these areas with TP around them. Provide acceptable signage. Areas of F/OS to be located
outside of the LOD.
C-502/C-504: TREE PROTECTION FENCING AND SIGNS HAVE BEEN ADDED.
3. Sheet 4/5: (phase 1 Erosion Plan):
a. Add SSF around perimeter of Conserved Open Space.
C-502/C-504: SSF HAS BEEN ADDED AROUND CONSERVED OPEN SPACE.
b. It appears that runoff from existing 24” culvert bypasses the Sediment Basin (SB-1).
Runoff leaving DD will enter roadside ditch, then get conveyed to an existing culvert.
Correct so that runoff leaving culvert enters the basin.
C-502: DD HAS BEEN REVISED SO IT WILL DISCHARGE INTO STR-3.
c. Correct the DD angle to direct flow into ditch at no greater than 90 degrees. Flow entering
ditch should not have to change course or reverse direction.
C-502: DD HAS BEEN REVISED SO IT WILL DISCHARGE INTO STR-3.
d. Add outlet protection at DD end.
C-502: OUTLET PROTECTION HAS BEEN ADDED.
e. Determine if existing roadside ditch is adequate or design one that is. Flow entering ditch
from DD should not blowout or erode side slopes.
C-502: DD HAS BEEN REVISED SO IT WILL DISCHARGE INTO STR-3. POST-
DEVELOPMENT FLOW TO EXISTING DITCH WILL BE LESS THEN PRE-
DEVELOPMENT FLOW.
4. Sheet 6: Please identify the hatching used near the outlet structure near entrance.
C-504: HATCHING HAS BEEN RESOLVED. OUTLET PROTECTION IS SHOWN.
5. Provide more information on SB-1 design. The completed worksheet in the ESC HB Spec. 3.14
shown on pages III-12 to III15 will do. Due to site conditions (SB in the flood plain) provide that
the riser structure contain the emergency spill way.
C-601: DETAILS ON SB-1 HAVE BEEN ADDED.
6. Show conserved open space easement.
C-503 THRU C-506: CONSERVED OPEN SPACE EASEMENT IS SHOWN.
Please let me know if you need additional information.
Sincerely,
Timothy Miller, P.E., L.S.
Principal