HomeMy WebLinkAboutWPO202100003 Correspondence 2021-08-25S�
608 Preston Avenue P 434.295.5624
Suite F434.295.1800
TIMMONS GROUP
Charlottesville, VA 22903 www.timmons.com
August 25, 2021
Emily Cox
Count of Albemarle
Community Development
401 McIntire Rd, Rm 227
Charlottesville, VA 22902
RE: Starbucks — 2231 Seminole Lane — VSMP Permit Plan Review — WP0202100003 -
Comment Response Letter
Dear Ms. Cox:
We have reviewed all of your comments from Rev. 2 dated July 13, 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. A SWPPP was not provided with this submission. Please submit a SWPPP for review. Ensure
it has the newest registration statement (attached to this comment letter).
A SWPPP is included with this submission. Signed documentation will be provide once
obtained.
Rev. 1): Comment partially addressed. SWPPP provided, but registration statement not
complete. Also, Section 9, signed certification must be signed.
A signed Registration Statement and Section 9 are included with this updated SWPPP.
2. Please state where the debris from the existing building will betaken.
Debris from the existing building will be taken to an approved landfill site.
Rev. 1): Please state comment response on plans, "Debris must be taken to an approved
landfill site."
This note has been added on Sheet C3.0.
3. The existing building appears to have a basement. Will fill material be brought to fill this in?
If so, please specify where it will come from.
Excess soil from the project site or clean fill from another site will be used to fill the
basement of the existing building.
ENGINEERING I DESIGN I TECHNOLOGY
Rev. 1): Please state the estimated required amount of fill on the plans.
Approximately 216 CY of fill will be required to fill the basement to proposed finished
grade. This note has been added to Sheet C3.0.
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code Section 17-404.
1. A PPP was not provided with this submission. Please submit a PPP for review.
A PPP in included with this submission within the SWPPP.
Rev. 1): Comment addressed.
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. A stormwater management agreement needs to be executed before plan approval.
Please contact Ana Kilmer [akilmer@albemarle.org 434.296.5832 x 3246] to
complete this task.
Acknowledged.
Rev. 1): Comment not addressed.
Acknowledged.
Rev. 2 : Comment not addressed.
The Stormwater management agreement has been executed and recorded with
the Clerk.
2. Nutrient credits should be purchased before plan approval. Please contact Ana
Kilmer to complete this task.
Acknowledged.
Rev. 1): Comment not addressed.
This process is underway but not complete.
Rev. 2 : Comment not addressed.
The required nutrient credits have been purchased. Documentation is included
with this submittal.
3. Please add the WPO number (WPO202100003) on the cover sheet.
The WPO number has been added to Sheet CO.O.
Rev. 1): Comment addressed.
4. Topography should have been completed or field verified within the past year. Current date
on the cover sheet is April 2019.
The site was field verified in October 2020.
Rev. 1 : Comment addressed.
5. Show the DB & PG for all existing easements and parcels.
This information has been added. See Sheet C2.0.
Rev. 1 : Comment addressed.
6. Please provide signed and sealed retaining wall plans/details.
Acknowledged. These will be provided once obtained.
Rev. 1 : Comment not addressed. Also, please ensure grading for the wall can occur within
the limits of disturbance and the property. Be sure to include wall tie -backs, etc.
A retaining wall design has been included with this submittal. There are tie -backs only on
the eastern portion of the wall. The wall along the southern property line does not require
tie -backs due to the shorter height throughout that portion of the proposed retaining
wall.
[Sheet C6.0] Please review drainage divides. This line in the existing and proposed
conditions below does not appear to follow contours:
Drainage areas shown on C6.0 have been updated to be clearer. The dividing line between
some areas are due to showing disturbed vs. undisturbed areas. We are showing this
distinction, so it is clear what the Improvement Factor in the energy balance equation
applies to and what is considered offsite.
Rev. 1 : Comment addressed.
8. Please provide a proposed cross section for the drainage behind the proposed wall.
A cross section and calculations have been added to Sheet C5.0 for the ditch behind the
eastern portion of the retaining wall. This will carry stormwater from the steep slopes east
of the wall. Due to the proximity of the wall to the southern property line, as well as the
direction of the less steep grade in that area, a ditch is not needed behind this portion of
wall.
Rev. 1 : Please show the drainage divide used for this cross-section design.
An extra viewport has been added to Sheet C5.0 to demonstrate this 0.17 ac area draining
to the ditch behind the wall.
9. Please show how the water behind the wall in the location shown below will be directed.
Concentrated water cannot be sent to the adjacent parcel.
An inlet (120) has been added to collect stormwater from behind the wall. See Sheet C5.0.
Rev. 1 : Comment addressed.
10. Please explain the note for the "2' curb cut for stormwater overflow". What overflow is it
referring to?
The purpose of this is in the case that inlet 116 (the yard drain east of the building) gets
clogged, or during a major storm event, overland relief is provided via this curb cut to
prevent the building from flooding.
Rev. 1 : Comment addressed.
11. Please show where roof drains will be located.
Roof drain locations have been added. See Sheet C4.0.
Rev. 1 : Comment addressed.
12. Please show calculations for the existing inlet that goes to Ex-100 (spread, etc). The drive
thru lane appears to drain to it through the existing channel.
The storm system has been updated and the storm pipe connection is now to the existing
inlet at the bottom of the existing concrete channel (EX-100). Additionally, Sheet C6.1 and
inlet calculations have been updated to include this inlet.
Rev. 1 Comment addressed.
13. The existing channel to the existing inlet that goes to Ex-100 is cracked and needs to be
repaired.
We are no longer utilizing this concrete channel.
Rev. 1 : Comment addressed.
14. Please show the velocity of stormwater going through the channel referenced in the above
comment and shown below.
We are no longer utilizing this concrete channel.
Rev. 1 : Comment addressed.
15. Please provide more details for the proposed SWM facility. Ensure there is adequate access
for maintenance to the facility.
Details for the proposed SWM facility have been added to Sheet C1.4.
Rev. 1 : Comment partially addressed. Please show the manhole maintenance access
locations in plan view.
The access manholes have been added to the plan sheets.
16. Since 9VAC25-870-66 C.2.b was used for flood protection, please show that the existing
conveyance systems currently experience localized flooding. If they do not experience
localized flooding, CA & C.3 must be used.
As discussed on the Teams call on March 16, 2021, and per email from Emily Cox on March
17, 2021, we do not need to show that there is currently localized flooding to use 9VAC25-
870-66 C.2.b for flood protection. Stormwater from this site travels to a pipe system,
which presumably outlets to the Rivanna River (+/- 1,700 LF from project site). We have
not witnessed localized flooding, and we do not have pipe data for these downstream
pipes, however, our proposed stormwater management design meets the intent of
improving the 10-year storm condition.
Rev. 1 : Comment addressed.
17. The proposed sidewalk near the front of the site does not appear to drain to analysis point 2
as shown in calculations (post area 2).
Grading for this proposed sidewalk has been adjusted to drain towards the project site.
See Sheet C5.0.
Rev. 1 : Comment addressed.
18. Please provide this checklist on the plans:
https://www.albemarle.org/home/showpublisheddocument?id=212
This checklist has been added to the VSMP Cover Sheet C0.0.
Rev. 1 : Comment addressed.
D. Erosion & 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. Please clearly show the extent of the managed slopes.
The hatch indicating the managed steep slopes has been updated to print clearer.
Rev. 1 : Comment addressed.
2. Ensure temporary seeding, dust control and permanent seeding are shown on all phases of
the plan.
TS, DC, and PS have been added to all phases of the plan appropriately.
Rev. 1 : Comment addressed.
3. [Sheet C2.1] This tree is not marked to be removed however it appears to be within the
clearing limits. Please clarify.
The referenced tree is not proposed to be removed and the limits of disturbance/clearing
have been updated.
Rev. 1 : Comment addressed.
4. [Sheet C2.1] Please locate and show which trees behind the building and near the proposed
wall are to remain and which are to be removed. The treeline shown on the plans does not
appear to be accurate.
The existing treeline has been adjusted at the back of the site per site visit observation
and the proposed treeline is located beyond the proposed grading limits. We're not able
to identify the exact number of trees to be removed without a tree survey and we do not
believe a tree survey is necessary per the ordinance.
Rev. 1 : Comment not addressed. Please show tree protection fencing to preserve the trees
you do not want to be removed.
Tree protection fencing has been added throughout the plans.
5. [Sheet C3.0] Please specify the retaining wall area as a critical erosion area.
The retaining wall area has been added to Sheet C3.0 as a critical erosion area.
Rev. 1 : Comment addressed.
6. [Sheet C3.1] The limits of disturbance appear to go offsite on both adjacent parcels. Do you
have permission or an easement for this work?
All work to be provided within property, right of way, or easements. The E&SC measures
and LOD have been adjusted.
Rev. 1 : Comment addressed.
7. Work and improvements appear to be proposed in the Virginia telephone and telegraph
easement. Do you have permission for that?
Telephone easement to be abandoned with quit claim, once building demo permit has
been acquired.
Rev. 1 : Comment addressed.
8. Please show a stockpile, laydown/staging and parking area.
Area for stockpile, staging, and parking has been added to the E&SC plan. See Sheet C3.1—
C3.2.
Rev. 1 : Comment addressed.
9. Ensure perimeter controls are sufficient. For example, how will sediment not leave the site
at this location?
Silt fence has been added north of the sediment trap. Additionally, a hatch has been
added to show the extent of the existing asphalt to be preserved for access to the
construction entrance.
Rev. 1 : Comment addressed.
10. Please show that silt fence is limited to areas of sheet flow with X acre per 100 ft.
A clean water diversion has been added along the proposed sidewalk towards 29 to limit
the stormwater going towards the SF along the north side of that sidewalk.
Rev. 1 : Comment addressed.
11. Please consider adding an initial phase to address the removal of the existing wall and
building, and installation of the new wall as the 1" step. A sediment trap may not be
necessary for this phase, especially if the existing pavement is preserved.
An additional phase has been added to the E&SC plans. See Sheet C3.1— C3.2.
Rev. 1 : Comment addressed.
12. Please revise the sequence of construction to be site specific.
The Sequence has been updated.
Rev. 1 : Comment addressed.
13. Sediment trap weir outfall cannot be directed as currently shown.
The sediment trap weir outfall has been adjusted in elevation as well as rotated to direct
water to the existing concrete channel.
Rev. 1 : Comment 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 me at
anna.fontaine@timmons.com .
Sincerely,
Anna Fontaine, PE
Project Engineer