HomeMy WebLinkAboutWPO201100071 Review Comments Erosion Control Plan 2011-10-15ALg�,��
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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: WPO- 2011 - 00071, RE- Store'n Station ESC Plan
Plan preparer: Mr. Nat Perkins, PE; NP Engineering
Owner: Jefferies IL LLC
Owner's Rep.: Mrs. Jo Higgins; Project Development Limited
Date received: 31 August 2011
Date of Comment: 15 October 2011
Engineer: Phil Custer
The ESC plan for the RE- Store'n Station (WPO- 2011 - 00071), received on 31 August 2011, has been
reviewed. The plan can be approved after the following comments have been addressed:
1. It appears that the ESC Plans were all printed at 30scale, not 40. If this is correct, please replace
all references to 40 scale with 30 scale.
2. On all three phases, please clearly show and label the limits of disturbance boundary.
3. Please show all proposed grading on Phase 2 and Phase 3. It is difficult to evaluate the adequacy
of these phases without proposed contours. Additional comments may be necessary because the
plan was not able to be fully evaluated.
4. Related to the previous comment, the sediment basin and sediment trap should be sized for the
largest watershed each facility will likely experience as the site is filled in. For instance, the site
will likely be tipped towards the sediment basin, since the stormwater facility is located in the
vicinity, so its drainage area will increase as the earthwork progresses.
5. Silt fence is frequently proposed perpendicular to contour lines in this plan which is not allowed
per state guidelines. In these instances, water will not travel through the fence but will be
redirected downhill, like a diversion. Please replace the silt fence on the east side of the property
line with a diversion from the northeast corner to the sediment trap. On the west end of the
property, please simply remove the silt fence. If a visual boundary is desired by the applicant, I
recommend a type of safety fence.
6. Please remove the silt fence from directly below the outlet of both settling facilities. Silt fence
cannot receive concentrated flow.
7. During the review of the preliminary site plan, the Chief of Current Development, Bill Fritz,
approved the disturbance of a 20ft wide section of the undisturbed buffer to the south. Please
show the area of the buffer that was approved for disturbance. It appears that the area shown on
this submittal does match the area approved by Bill. If the area proposed for disturbance is, in
fact, different, another waiver of this disturbance may need to be processed.
8. The embankment of the sediment basin ties into existing grade within the undisturbed buffer (see
where the 676 contour line would be). Please modify the plan to make sure no disturbance to the
undisturbed buffer occurs, other than the area previously authorized.
9. In plan view, please draw the sediment basin bottom as 671.
10. Please show Permanent Seeding (PS) symbols throughout the plan where necessary.
11. Please include the county's paved wash rack detail in this sheet set. This detail can be found in the
county's design manual on page 28 of 35.
12. The county has updated its standard ESC Note set. Please use the latest version found in the
county's design manual.
13. An analysis of the downstream channel per Minimum Standard 19 was not provided with the ESC
plan. Please refer to page 7 (of 35) of the County's Design Manual and the Virginia Erosion and
Sediment Control Handbook for what the county expects for an analysis of downstream channels.
Per state law, this analysis must be performed using the 24 -hour storm.
14. Please provide the cross - sections and calculations (2 -year velocity and 10 -year capacity) for the
new VDOT ditch. Please specify any liner, if necessary.
15. To receive a bond estimate, please provide a completed Bond Estimate Request Form to the
County Engineer after all comments have been addressed. All owners of properties disturbed
with this application must sign this document and be party to the bond unless all offsite
easements are recorded. The easements must be written in a manner that allows the county and
its assigns to the construction site.
Pitc: El csc PBC WPO- 2011 -00071 RE- Storc'n Station ESC Plan.doc