HomeMy WebLinkAboutWPO201900040 Correspondence 2019-08-23s 0 e ! # 41
TIMMONS GROUP
YOUR VISION ACHIEVED THROUGH OURS.
August 21, 2019
Emily Cox
County of Albemarle
Dept. of Community Development
401 McIntire Rd
Charlottesville, VA 22902
608 Preston Avenue P 434.295.5624
Suite 200 F 434.295.8317
Charlottesville, VA 22903 www.timmons.com
RE: Yancey Lumber Yard — VSMP Permit Plan Review — WP0201900040 - Comment Response
Letter
Dear Ms. Cox:
We have reviewed all of your comments from August 1, 2019 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. Registration statement and certification (section 9) must be signed.
The Registration statement and certification have been signed and are included.
B. Pollution Prevention Plan (PPP
1. No comments.
C. 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. Nutrient credits must be purchased before plan can be approved. Contact Ana
Kilmer (akilmer@albemarle.org) to begin the process.
Acknowledged.
2. It appears this plan is showing the drainage area to be the same as the disturbed
area. This does not appear to be correct. Please revise and ensure that the correct
drainage area to the point of analysis is analyzed.
CIVIL ENGINEERING I ENVIRONMENTAL I SURVEYING I GIs I LANDSCAPE ARCHITECTURE I CONSTRUCTION SERVICES
Plan has been updated so that limits of disturbance/ site area is analyzed for stormwater
quality and quantity.
3. Provide back-up showing the justification from CN of 96 to CN of 93. Similarly, show
a map clearly showing the areas used in the VRRM spreadsheet for pre and post
areas (impervious, turf, etc).
Hatches have been added to sheet C6.0 to clarify pervious and impervious areas.
4. The plan narrative references design limits of a retaining wall, however, those limits
are not shown or explained in this plan.
The narrative has been updated to provide more information. The retaining wall
referenced is called out as "1' (W) conc wall" on the plans and is south of the "current" limits
of disturbance. The area to the south of that was previously all stone and asphalt. The area
was previously disturbed without a permit to build the wall and concrete pad shown as the
limits of disturbance for previous construction. Sheet C1.0 has a typical section of the existing
wall and shows the constraints used for grading.
5. Clearly outline how 9VAC25-870-66 is met (channel and flood protection, limits of
analysis, etc).
Sheet C6.0 has been updated. Channel protection is met through Energy Balance by the
reduction on impervious area. Flood protection is met through a slight decrease in the 10-
year storm.
D. 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. The construction entrance should be within the limits of disturbance.
Limits of disturbance have been updated.
2. The construction entrance should have a wash rack with an area for the water to go.
A note has been added to ensure wash water drains to and is filtered by the inlet
protection.
3. The sequence of construction should say that all permits must be obtained before
any work shall begin. Also, the pre -con is not always on -site. Sometimes it is in the
office.
Note has been added to part 1 of the sequence of construction.
4. Ensure there are sufficient perimeter controls (any silt fence necessary, right-of-way
diversions, etc).
Entire disturbed area drains to the inlet protection which is able to handle 1 acre of
disturbance. Clean water diversions have been added to make sure drainage area to inlet
protection is under 1 acre during construction.
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,
Jonathan Showalter, PE
Project Engineer