HomeMy WebLinkAboutWPO202100054 Correspondence 2021-11-10S�
608 Preston Avenue P 434.295.5624
Suite F434.295.1800
TIMMONS GROUP
Charlottesville, VA 22903 www.timmons.com
November 10, 2021
John Anderson
County of Albemarle
Community Development
401 McIntire Rd, North Wing
Charlottesville, VA 22902
RE: Keswick Family Pool — VSMP Permit Plan Review — WP02021-00054 - Comment Response
Letter
Dear Mr. Anderson:
We have reviewed all of your comments from October 29, 2021 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. Revise the SWPPP title page to include ref. to WP0202100054.
Addressed.
2. Please check to see if file 'flatten' issue may have affected SWPPP submittal by
stripping information; thanks for discussing this with me 10/06/2021.
Addressed.
3. (Rev 1)
a. SWPPP, Sec. 1 (Registration Statement)
i. Sec. V: Registration statement must be signed prior to WPO plan
approval. Timmons Group is eligible/appropriate, since TG prepared
the SWPPP for Keswick Family Pool.
Signed document is included with this submission.
ii. Sec IV.B: Please check 'yes' box since an ESCP has been submitted for
review.
Box has been checked.
ENGINEERING I DESIGN I TECHNOLOGY
b. SWPPP, SePPP:
i. Sec 6 A, PPP Exhibit: Please indicate an initial location for rain gauge.
Rain gauge and label has been added to the PPP sheets.
ii. Sec 6 E: List named individual responsible for PPP (TBD. or list
individual)
Section 6E has been updated and included with this submission.
c. Sec 8: List named individual responsible for ESC compliance inspections (TBD,
or list individual)
Section 8 has been updated and included with this submission.
d. Sec 9: Signed Certification: please sign.
Section 9 has been updated and included with this submission.
4. Note: Once SWPPP approved, Engineering should be positioned to register project
with DEQ for permit. A VAR10 permit is required prior to scheduling pre -
construction for Keswick Family Pool.
Acknowledged.
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code Section 17-404.
Rain gauge and label has been added to the PPP sheets.
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a
SWMP. This plan is disapproved for reasons listed below. The stormwater management plan
content requirements can be found in County Code Section 17-403.
Note: Pre -construction is point project receives a grading permit, but grading permit is also
contingent upon 0.34 lb nutrient credit purchase Please coordinate purchase documents
with Ana Kilmer, CDD Management Analyst, at earliest convenience 0.34 is a set value.
Documents have been sent to Ana for review, returned to us on November 10`h, 2021. The
documents have been sent to owners for signatures. Signed documents will be forwarded
to County upon receipt.
1. General:
a. Add WP0202100054 to calculation packet cover.
Addressed.
b. Add WP0202100054 to plan title sheet.
Addressed.
2. C4.0:
a. Show/label public drainage easement (SWM facility outfall pipe).
(Rev.1) On C6.6, label easement over SWM facility outfall pipe 'public
drainage easement' rather than 20' permanent stormwater management
facility easement. SWM facility and public drainage easement deeds are
distinct; each deed references plaited easements, which should be labeled
either SWM facility easement (variable SWM...), or 20' public drainage
easement.
The labels have been revised for this submission.
b. Show/label SWM facility easement. Addressed.
c. Please find easement application at:
https://www.albemarle.org/home/showpublisheddocuments/1052/6376240
89314100000
Addressed.
3. C5.0:
a. Note 3: Please ensure comment allowing contractor discretion with rooftop
storm routing is consistent with post -developed hydraulic routings in
calculation packet. Allowing the contractor flexibility to route roof leader
lines to 'nearest inlet' is inconsistent and may cause discharge higher than
reported in the calculation packet, if runoff intended to reach detention
bypasses detention.
Addressed.
b. Recommend label, note, or legend identify permeable pavers as Level 1
permeable pavers.
Addressed.
4. C6.2:
a. Include Construction Installation steps from VA DEQ Stormwater Design
Specification Design Specification No. 7.
Addressed.
b. Include underground detention Mfr. Specifications, typical details, and
specific details for proposed SWIM facility.
Addressed.
5. C6.3:
a. Check upgradient drainage areas for Area 2 and Area 3, since it appears
upgradient areas may drain to permeable pavers in these areas.
Addressed.
Check CDA ratio, 3.09:1, permeable pavement drainage area 4, since VA DEQ
Stormwater Design Spec. Level 1 max. CDA ratio is 2.5:1. Revise, as needed.
Addressed.
6. C6.0:
a. Stormwater Narrative: Please revise/clarify lb. nutrient credits proposed
(0.33 or 0.26 lb.)
0.34 Ib of purchase required. Addressed.
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 for reasons listed, below. The erosion control plan content
requirements can be found in County Code Section 17-402.
1. C3.0:
a. Check sediment trap #2 wet storage provided (61.9 cy) v. storage required
(65.5 cy). (Rev 1) Partially addressed. As follow-up: ST#2 revised, but ST#1
wet storage req u ired >storage provided. Please revise design ST#1.
Addressed.
2. C3.2:
a. Compare area of disturbance, 1.75 Ac., with VRRM.xIs 1.53 Ac. Please
reconcile. (Rev 1) Addressed. 1.69 Ac LOD now consistent across C3.2,
VRRM.xIs, notes, labels, etc. Addressed.
b. Label ST1 floor dimensions, L x W. Addressed.
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 or email at
Jessica.denko@timmons.com .
Sincerely,
Jessica Denko
Project Manager