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401 McIntire Road, North Wing
County
of Albemarle
Charlottesville, VA 22902-4579
Telephone: 434-296-5832
COMMUNITY
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DEVELOPMENT DEPARTMENT
WWW.ALBEMARLE.ORG
VSMP Permit Plan Review
Project title:
Galaxie Farm Subdivision VSMP Plan
Project file number:
WPO2020-00037 [ Note: to be reassigned a new WPO #1
Plan preparer:
Scott Collins, Collins Engineering [ scotte collins-en ing eerieg
com ]
200 Garrett St., Suite K, Charlottesville, VA 22902
Owner or rep.:
David S. or Anna Marie Witmer
444 Rookwood Drive, Charlottesville, VA 22903
Applicant:
Kent Henry, Riverbend Development Inc. / 455 Second Street
SE, Suite 201
Charlottesville, VA 22902 [ kent(d�riverbenddev.com ]
Plan received date:
6 Aug 2021
Date of comments:
28 Sep 2021
Reviewer:
John Anderson
County Code section 17-410 and Virginia Code §62.1-44.15:34 requires the VSMP authority to act on any
VSMP permit by issuing a project approval or denial. This project is denied for reasons listed below. The
VSMP application content requirements can be found in County Code section 17-401.
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.
Please submit SWPPP.
B. Pollution Prevention Plan (PPP) — See above.
The PPP content requirements can be found in County Code section 17-404.
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.
1. Please submit Calculation Packet.
2. An approved WPO plan and ROAD plan (nearly approved) (previous design by Shimp Engineering /SE)
require replacement. Proposed preliminary plat replaces an approved preliminary plat, SUB201900198
(2/20/20). [ Please submit plan to replace ROAD plan SUB2020-00098, since that road plan is not
approved. In addition, the road network is significantly altered. Streets must be re -reviewed: plan, profile,
drainage, comps, etc. CDD will assign a new file # to the new ROAD plan.] Engineering received an
Amendment Application for WP02020-00037 on Aug-6, 12021, but a new WPO # is required. (Plan will
keep its place in review queues.) SE design is withdrawn. A new subdivision design by Collins
Engineering (CE) bears slight resemblance to withdrawn design.
3. As preliminary plat and initial site plan designs are revised in response to comments, please ensure that
ROAD and WPO plans are consistent with SUB2021-00125 (new preliminary plat) and SDP2021-00059
(new ISP), both conditionally approved. SDP2020-00072 (SE initial site plan) was withdrawn 6/22/21.
4. Approved ROAD and WPO plans are required prior to final site plan and final subdivision plat approval.
Engineering Review Comments
Page 2 of 5
5. Sealed geotechnical retaining wall design is required. Engineering review /approval of retaining wall plans
is required prior to ROAD and WPO plan approval. A wall is coincident with a proposed SWM facility.
And Galaxie Farm Lane cannot persist in its current location absent a 6' retaining wall across Lots 42-48.
6. Please ref. Engineering ISP review comments d. 9/5/21 (email, 9/5/2021 9:28 PM).
[ Note: Applicant submitted a combined initial site plan and preliminary plat. ]
7. [ Note: Additional final plat review comments are possible, especially relative to off -site easements, SWM
facility /drainage easements, wall maintenance agreement, improvements proposed on Albemarle County
School Board parcel, and on -site /off -site proposed improvements to Galaxie Farm Lane, a public street,
private street, and driveway over a short interval occurring at, near or across development parcel
boundaries. ]
8. Provide metes and bounds for all easements.
9. Deeds are required to be recorded for SWM facilities, SWM access, and public drainage easements.
10. Sheet 3
a. Revise sequence of construction, as needed, to provide additional detail or revision in response to
comments. Phase 1 item 8 would appear to need to list earlier in the sequence, to allow contractor
access to perform steps outlined in items 5 — 7.
b. With Phase 1 sequence, please mention responsibility to coordinate with USACE and obtain
USACE permit, as needed, to perform work in Cow Branch.
c. Recommend Phase I sequence note reference ROAD plan for specific design and specifications of
the 4-line (dbl. 60" / dbl. line 48") culvert crossing at Cow Branch. These culverts will not be
removed after WPO plan ESC phase 1, and must be installed per VDOT /USACE guidelines and
meet relevant design standards, permit requirements, etc.
11. Please submit hydrologic /routing calculations (SWM quality /quantity) that support design, and hydraulic
calculations that support storm system design for this development. If submitted with initial plan received
8/6/21, and overlooked, reviewer will try to review within 10 business days of submittal.
12. Similarly, please submit SWPPP for this development. If overlooked, will review as expeditiously as
possible [ see item 17., below Note].
13. Sheet 12
a. Debris cage detail appears inconsistent with 5 — 12" DIA mid -flow orifices located >7' above
basin floor, since debris cage detail appears to be designed for a floor level orifice. Please provide
debris cage detail appropriate to elevated orifice.
b. Makes ref. to Calc. packet —please submit calculation packet.
c. Subarea B discharges to a stream, a natural stormwater conveyance system: 9VAC25-870-6.6B.3.
applies. Placing riprap in a stream bed does not transform a natural stream to a manmade
stormwater conveyance system. Cow Branch is a natural stream, and DEQ has explicitly informed
local program authorities that discharge must meet energy balance at point riprap terminates,
unless a manmade stormwater conveyance system continues downstream. Engineering cannot
defend principle that riprap in a stream bed (covering it, bank to bank) qualifies as a manmade
stormwater conveyance system. Outfall subarea B requires revision. Unless USACE explicitly
approves design, please remove riprap from stream bed. Also, regardless of USACE perspective,
Engineering Aocal program authority cannot approve a plan that contravenes DEQ guidance.
Energy balance applies at this discharge, Subarea B.
14. Sheet 13: Calculations should support need for riprap at outfall #1, which appears excessive. Were facility
outfall to shift even 20-ft south, it appears discharge would cross stream buffer to Cow Branch in a lightly
defined drainage feature. Provided riprap is sized per VESCH to provide V2-n erosion protection, no need
to extend riprap nearly to perennial stream CL (Cow Branch). Also, calculations should show energy
balance is met at dry detention base outfall #1.
15. All development discharge points must meet energy balance, if discharge is to a natural stormwater
conveyance system, or else be sheet flow discharge.
16. Please incorporate 9/5/21 Engineering ISP review comments into revised WPO, as needed.
(SDP202100059)
17. Note: Reviewer made multiple periodic assurances that review comments would be sent, seemingly always
in a day or two. In light of this, Applicant is welcome to send hi -priority email to reviewer with link to
Engineering Review Comments
Page 3 of 5
calc. packet, SWPPP, revised WPO plan, with periodic or daily reminders, which are effective. Without
promising a specific response window given comprehensive unreliable recent assurances, this VSMP plan
resubmittal will be a priority, and a quick review may help offset initial review timeline. We hope so.
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. Sheet 4
a. Stream bypass should bypass all downstream improvements, including riprap /recommended
concrete apron such that work may be in the dry.
b. Revise stored fuel label to include additional capacity to accept 10-yr rainfall event without
overtopping berm containment.
c. Please provide label that specifies if new material is placed atop Ex. Galaxie Farm Lane from Int.
Rt. 20 to point Galaxie Farm Lane crosses onto County of Albemarle School Board parcel.
2. Sheet 5: Please see notes elsewhere concerning riprap outfall protection design, which appears excessive.
3. Sheet 6
a. Two labels overlap, one obscuring the other (sign "warning" quick sand, keep out). Please revise
so underlying label is readable.
4. Sheet 7
a. Tree protection should not extend across Cow Branch.
b. Please label heavy -dashed line feature near eastern -most IP that crosses double line 48" DIA RCP
at Cow Branch, Galaxie Farm Lane.
c. Engineering does not anticipate County of Albemarle School Board objecting to ESC measures
required to be placed on School Board Property, but notes that typically any owner of a TMP with
ESC measures or SWM facilities located on them would be required to be party to a WPO plan
bond. Engineering defers to county Management Analyst. County of Albemarle inspectors would
have unrestricted right of entry access to County of Albemarle School board parcel, for purposes
of ESC inspection.
5. Sheet 8
a. Recommend notch or complete break in baffle to allow detained sediment -laden water on N side
of baffle to reach riser, since baffles are proposed to be installed to elevation 478', while invert out
=470.'
b. Provide scale profile of sediment basin that shows:
i. All critical design elevations, including
1. Floor of basin
2. INV out
3. Low -flow orifice
4. Dewatering device
5. Riser rim
ii. Principal spillway pipe /barrel (label slope, length, DIA)
iii. Collars
1. Dimensions labeled
2. Position of collars shown true to scale
c. Label floor of sediment basin.
d. Include sequence note that outlines sediment basin to detention basin conversion, including
removal /disposal of saturated material.
e. Recommend ST#2 design bottom of stone weir elevations be rounded to nearest 0.1'.
6. Sheet 9
Engineering Review Comments
Page 4 of 5
a. Coordinate stream impacts /stream loss that occurs with proposed 4-line crossing at primary
subdivision access, at Cow Branch, on Galaxie farm Lane, with USAGE. [ Note: proposed riprap
should be limited to amount required by calculation as necessary for inlet /outfall protection at this
substantial wingwall structure. Recommend replace riprap at inlets /ouftall with poured concrete
aprons, countersunk 6" as is more typical for structures of this dimension (4', 5' DIA culverts).
Engineering defers to VDOT on wingwall design, hydraulic analysis, etc., at this public street
stream crossing, structure to be maintained by VDOT.
b. Ref. comments elsewhere or at SDP202100059 concerning need for recorded Maintenance
Agreement for retaining walls that span lot lines.
c. Please label riprap inlet /outfall protection dimensions ( L x W x D).
7. Sheet 10
a. Ref. comments elsewhere or at SDP202100059 concerning need for recorded Maintenance
Agreement for retaining walls that span lot lines.
b. Provide evidence of coordination with and permission from School Board County of Albemarle,
VA, to install proposed pipe structure and VDOT Std. EW-1 on TMP 91-11.
8. It is unclear whether proposed native steep slope mix with annual ryegrass by Ernst Conservation Seeds is
hardier than grass —please provide additional details for proposed Ernst steep slope mix
Process:
After approval, plans will have to be bonded. The bonding process is begun by submitting a bond estimate request
form and fee to the Department of Community Development. One of the plan reviewers will prepare estimates and
check parcel and easement information based on the approved plans. The County's Management Analyst will
prepare bond agreement forms, which will have to be completed by the owner and submitted along with cash,
certificates or sureties for the amounts specified. The agreements will have to be approved and signed by the County
Attorney and County Engineer. This may take 24 weeks to obtain all the correct signatures and forms.
Stormwater Management Facilities Maintenance agreements will also have to be completed and recorded. The
County's Management Analyst or other staff will prepare the forms and check for ownership and signature
information. The completed forms will have to be submitted along with court recording fees.
This project requires separate easement plat application, review, and approval. Once plat is reviewed and comments
are addressed, Engineering will format template deeds (SWM / public drainage) to be recorded with the plat. Please
submit easement plat application at earliest convenience. Note: easement plat with deeds must be recorded prior to
receiving a Grading Permit.
Also, project proposes to 9.38 lb. nutrient credit purchase. Please coordinate purchase with Ana Kilmer, county
Management Analyst prior to purchase since specific project data is required to be listed on Bill of Sale and
Affidavit. Ms. Kilmer maybe reached at 434.296-5832 -x3246 / akilmer(awbemarle.org .
After bonding and agreements are complete, county staff will (if LOD > 1 Ac.) enter project information in a DEQ
database for state application processing. DEQ will review the application information based on local VSMP
authority approval. At this time, the DEQ portion of the application fees will have to be paid directly to the state. For
fastest processing, this is done electronically with the emails provided on the application. DEQ should notify
applicants with instructions on how to pay fees. When DEQ approves the application, they will issue a permit
coverage letter. This should be copied to the county.
After DEQ coverage is issued, via the coverage letter, the County can hold a pre -construction conference.
Applicants must complete the request for a pre -construction conference form, and pay the remainder of the
application fee. The form identifies the contractor and responsible land disturber, and the fee remaining to be paid.
Engineering Review Comments
Page 5 of 5
This will be checked by county staff, and upon approval, a pre -construction conference will be scheduled with the
County inspector. At the pre -construction conference, should everything proceed satisfactorily, a joint VSMP and
grading permit will be issued by the County so that work may begin.
County forms can be found on the county website forms center under engineering,
hftp://www.albemarle.orWdeptforms.asp?del2artment--cdenMo
Thank you.
Please call if any questions — tel. 434.296-5832-x3069, or email 4anderosn2(a albemarle.org.
WPO2020-00037 Galaxie Farm—NewWPO to be assigned 092821