HomeMy WebLinkAboutWPO202100042 Review Comments WPO VSMP 2021-11-04t� OF ALB
County of Albemarle
COMMUNITY DEVELOPMENT DEPARTMENT
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VSMP Permit Plan Review
Project title: VSMP Plan Bamboo Grove
Project file number: WPO2021-00042
Plan prepares Shimp Engineering, 912 E. High St., Charlottesville, VA 22902
Keane Rucker, FIT, keane(a),shimp-engineering.com
Justin Shimp, PE,Iustin(a),,shimp-engineering.com
Owner or rep.: Bamboo Grove LLC
Plan received date:
(Rev. 1)
Date of comments:
(Rev. 1)
Reviewer:
92 Oak Forest Circle
Charlottesville, VA 22906
2 Aug 2021
13-Oct 2021
17 Sep 2021
4-Nov 2021
John Anderson
401 McIntire Road, North Wing
Charlottesville, VA 22902-4579
Telephone: 434-296-5832
WWW.ALBEMARLE.ORG
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 reason relating to SWPPP
only. The VSMP application content requirements can be found in County Code section 17-401.
Please see item A.6. below. Calculation packet is approved, this date.
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 SWPPP title page to include correct TMPs (05500-00-00-068C0; 05500-00-00-068D0) and Project
Name (Bamboo Grove VSMP). (Rev. 1) Addressed.
2. Include ref. to WP0202100042 in SWPPP title. (Rev. 1) Addressed.
3. Revise Owner to Bamboo Grove Development, LLC, consistent with Sec. 9 Certification Statement. (Rev.
1) Addressed.
4. Sec. 1 -Registration Statement (Rev. 1) Addressed.
a. Sec. I.A. -Please revise Operator Name to Bamboo Grove, LLC, consistent with Sec. 9.
b. Sec. ILF. —Leave blank since parcels are not located within Albemarle County MS4.
5. Sec. 4, 5 -Update to reflect ESC /SWM plan revisions. (Rev. 1) Addressed.
6. Sec. 5: Please remove HydroCAD routings from SWPPP. Routings in Cale. booklet are sufficient. (Rev. 1)
Partially addressed. As follow-up, please move pg. 24 of SWPPP (Sec. 5 SWPPP divider) to position just
prior to pg. 22. Then, remove 13 pgs., beginning pg. 25, ending pg. 37, as these are calculations that should
be (and may be) included with calculation packet, but since they are not plans, they should not be grouped
with sheets C 13, C 14 in the SWPPP, as SWM Plan.
7. Sec. 6.A. /Exhibit: Locate rain gauge within parcel boundaries, outside public RW. (Rev. 1) Addressed.
8. Sec. 6.E.: Person responsible for PPP must be identified prior to pre -construction, but not for WPO plan
approval. (Rev. 1) Persists. Applicant response (letter d. Oct-13, 2021): `Noted, since this is not known
yet, it will be updated once a contractor is selected before Precon. meeting.'
B. Pollution Prevention Plan (PPP) —see SWPPP item 7., above (Rev. 1) Addressed.
The PPP content requirements can be found in County Code section 17-404.
Engineering Review Comments
Page 2 of 4
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This
plan is approved.
1. C13
2. C14
a. Note: Project proposes to meet water quality requirements with combination of forest -open space
easement and _ nutrient credit purchase. Forest -open space easement must be recorded
prior to plan approval and requires separate plat application and review /approval process.
Nutrient credit purchase is not required for plan approval but is required to receive a Grading
Permit. Please coordinate nutrient credit purchase with Ana Kilmer prior to finalizing purchase, as
both bill of sale and affidavit must list project specific information (WPO4, project name, project
IIUC, 0.51 lb. of credits, etc.) Please coordinate with Ms. Kilmer at earliest convenience
(434.296-5832-x3246, akilmer(a albemarle.org ). Please find easement plat application at:
https://www.albemarle.org/home/showpublisheddocument/1052/637624089314100000. (Rev. 1)
Persists. Applicant: `Noted. After coordinating with the client, they prefer to expedite the
timeline by removing the Forest -Open Space Easement (thus removing the requirement for an
approved plat pre -approval) and plan to only purchase nutrient credits. As such, the VRRM
spreadsheet has been revised to only include the limits of disturbance. To satisfy updated VRRM
requirements, an additional 0.08 lbs must be purchased, for a total of 0.59 lb/yr.'
b. Include (image of) Construction Record Drawings (As -built) for VSMP on the plans; link:
https://www.albemarle.org/home/showpublisheddocument/3381/637327510536700600 . (Rev. 1)
Addressed.
c. Provide reference to dry detention pond design criteria. (Rev. 1) Addressed.
d. Label dry detention pond floor dimensions L x W. (Rev. 1) Addressed.
e. Provide detailed profile for pond structures. (Rev. 1) Addressed.
i. Riser
ii. Riser base elevation
iii. Existing /proposed grade
iv. Pond floor
v. Pond structures /see hydroCAD routings
1. 18" culvert (primary spillway)
2. 8" orifice
3. 5' DIA riser
4. Emergency spillway (dimensions /material)
f. Plan view of dry detention pond is missing linework, labels, leaders, etc. Provide complete plan
view design with level of detail required to evaluate design, estimate bond amount, construct,
inspect, and operate this facility. (Rev. 1) Addressed.
g. Provide dry detention pond installation steps on the plan. (Rev. 1) Addressed.
h. Provide periodic dry detention pond inspection guidelines on the plan. (Rev. 1) Addressed.
i. Include notes /guidelines to convert sediment trap to dry detention pond. (Rev. 1) Addressed.
a. Pre- /post -developed offsite overland sheet flow is intuitively an identical longest path. This may
be a misconception, but whatever sheet flow path is shown for upslope offsite runoff, it is a single
path perpendicular to existing contours, and is unaffected by on -site downgradient development,
or change to on -site contours. When offsite sheet flow encounters altered site grading, that would
appear to be the point pre- /post-dev storm runoff may diverge in pre- /post condition (sheet,
shallow concentrated, concentrated). Please identify longest off -site sheet /SC flow paths and
represent these as pre- /post-dev runoff condition, and revise graphics /calculations, as needed.
Else, correct misconception. (Rev. 1) Addressed.
b. Please update 1-yr, 10-yr page references to Calculation booklet, pp. 16, 22, 36, 55 appear
inaccurate. (Rev. 1) Addressed.
Engineering Review Comments
Page 3 of 4
c. Check 1-yr, 10-yr values against Calculation booklet, for example: Calc. booklet reports 24-hr 1-
yr QP,e=3.48cfs, while plan list 3.74cfs. Calc. booklet reports 24-hr 10-yr Qp,=13.64cfs, while
plan list 14.35cfs. Please check plan v. calculation booklet values for consistency. Revise energy
balance equation and plan table values, as needed, to correspond with booklet HydroCAD routing
values. (Rev. 1) Addressed.
d. 3-A7 profile: provide label /note specifying subgrade compaction for pipes /structures. Entire
pipe -structure network is in fill. (Rev. 1) Addressed.
3. C L Tax Map parcels appear to correspond with HTC development, please revise. (Rev. 1) 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 approved.
1. C9
a. Revise CE label to PCE (paved construction entrance), provide ACDSM paved wash rack detail
on sheet C 12 (p. 8 /ACDSM). (Rev. 1) Addressed.
b. CWD appears to concentrate sheet flow (offsite clean runoff) and divert it toward Orchard Drive;
design relies on slight swale to route it beneath (paved) construction entrance. Provide barrier to
prevent higher -than -anticipated concentrated /channelized diverted flow from causing flooding in
Orchard Drive (provide an earth berm, more pronounced grade, etc.). (Rev. 1) Addressed.
c. Project proposes ESC measures within public right of way and a diversion immediately adjacent
to edge of pavement. VDOT land use permit is required. (Rev. 1) Addressed.
d. Provide construction entrance culvert IP. (Rev. 1) Addressed.
e. Provide grade required to install construction entrance culvert in ESCP Phase 1. (Rev. 1)
Addressed.
f Label trap outfall /weir riprap L x W dimensions. (Rev. 1) Addressed.
g. Label sediment trap. (Rev. 1) Addressed.
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 are 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 [forest -open space /SWM /public drainage] easement plat application at earliest convenience. Note:
easement plat with deeds must be recorded prior to receiving a Grading Permit.
Also: plan proposes 0-44 0.59 lb. nutrient credit purchase. Although nutrient credit purchase is not required for
WPO plan approval, it is required prior to pre -construction, to receive a Grading Permit.
Engineering Review Comments
Page 4 of 4
After ^9^ ea, eFage :s issued, via the eavoFago letteF, the County can hold a pre -construction conference.
Applicants must complete the request for a pre -construction conference foam, and pay the remainder of the
application fee. The form identifies the contractor and responsible land disturber, and the fee remaining to be paid.
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 VSNIP 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 Applications:
httos: //www.albemarle. org/government/communitv-develonment/aooly-for/engineering-aupl ications
Thank you.
Please call if any questions — tel. 434.296-5832-x3069, or email 4anderosn2(a),albemarle.or9.
WPO202100042—Bamboo Grovel 10421rev I