HomeMy WebLinkAboutWPO201900034 Correspondence 2020-01-31s0e!#4116
TIMMONS GROUP
YOUR VISION ACHIEVED THROUGH OURS.
December 17, 2019
Matt Wentland
County of Albemarle
401 McIntire Rd, Rm 227
Charlottesville, VA 22902
608 Preston Avenue P 434.295.5624
Suite 200 F 434.295.8317
Charlottesville, VA 22903 www.timmons.com
RE: UVA Encompass Health Rehabilitation Hospital — VSMP Permit Plan Review —
WP0201900034 - Comment Response Letter
Dear Mr. Wentland:
We have reviewed all of your comments from August 19, 2019 (Rev.1) and made the necessary
revisions. Please find our responses to the comments below in bold lettering.
A. Stormwater Pollution Prevention Plan (SWPPP)
The SWPPP content requirements can be found in County Code section 17-405. A SWPPP
must contain (1) a PPP, (2) an ESCP, (3) a SWMP, and (4) any TMDL measures necessary.
1. Provide a completed Registration Form. Section IA and Section VI will need to be filled
out.
The Registration Form shall be completed and signed prior to VSMP approval.
Rev.1 Comment not addressed, response noted.
Acknowledged. Form to be signed prior to approval.
2. Complete the Signed Certification (section 9 of the SWPPP)
A signed certification to be provided prior to VSMP approval.
Rev.1 Comment not addressed, response noted.
B. Acknowledged. Form to be signed prior to approval.
C. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17-404.
1. The PPP is acceptable at this time.
Acknowledged
CIVIL ENGINEERING I ENVIRONMENTAL I SURVEYING I GIs I LANDSCAPE ARCHITECTURE I CONSTRUCTION SERVICES
D. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a
SWMP. This plan is disapproved, and the reasons are provided in the comments below. The
stormwater management plan content requirements can be found in County Code section
17-403.
1. This plan cannot be approved until the Loop Road VSMP and Road Plans have been
approved and bonded.
Acknowledged. The Loop Road VSMP and Road Plans will be approved and bonded prior to
WPO201900034 approval.
Rev.1 Response noted.
Loop Road drawings have been approved. Bonding currently in process.
2. 1 ne riprap Deiow uuvei 100 is shown on a slope and not going into a defined channel.
The riprap outlet has been moved further down the slope to outfall into an existing channel.
Rev.1 Comment addressed.
3. While the existing pond does provide quality and quantity control for the drainage area,
the discharge from the site will still need to make it to the pond without causing
erosion. Provide measures and/or an analysis to show how the site's discharge meets
DEQ 1113 or IIC quantity compliance.
A 84" CMP Detention system has been provided to meet channel protection and flood
protection requirements. Sheet C6.2 has been revised to provide calculations for this system.
Rev.1 Comment addressed. In the future, the analysis point should be shown at the point of
discharge into the natural channel (which it appears the calculations match).
The proposed stormwater management system has been revised to reflect a dry pond.
Revision 1 Comments:
4. Prior to plan approval, an easement plat with deed will be required for the SWM facility
easement. The deed will be prepared by staff after submittal of the plat.
Acknowledged. Proposed easement line work can be found on Sheet C6.3. A plat will be
submitted for County review following acknowledgement/approval of preliminary alignment.
5. Provide an additional access point to the UG detention on the other side of the weir
plate.
The UG detention system has been removed from the project.
E. Erosion and Sediment Control Plan (ESCP)
Virginia Code 62.1-44.15:55 requires the VESCP authority to approve or disapprove an ESCP.
This plan is disapproved, and the reasons are provided in the comments below. The erosion
control plan content requirements can be found in County Code section 17-402.
1. Provide perimeter measures below all areas of disturbance.
Additional perimeter measures have been provided to capture as much runoff as possible. See
Sheets C3.2 — C3.4.
Rev.1 Comment partially addressed. Controls are required below all disturbances. Several
areas still have nothing below them to intercept or filter the runoff and silt fence is shown in
proposed slopes. The Handbook wants the SF to be located at least 5' beyond the base of
disturbed slopes.
E&SC measures have been revised to reflect the addition of the sediment basin and dry pond.
Revision 1 Comments:
2. Provide copies of all Army Corp permits related to the wetland disturbance.
Permits to be provided upon receipt.
We have included PDF copies of the plans and calculations for your review. If you have any
questions or comments, please feel free to give me a call at 434.295.5624.
Sincerely,
Andrew Allison, PE
Project Engineer