HomeMy WebLinkAboutWPO202000036 Review Comments WPO VSMP 2020-08-13Phone (4341296-5832
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1T
COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902-4596
Fax(4341972-4126
VSMP Permit Plan Review
Afton Stables - VSMP
WPO202000036
Mike Myers, PE / 30 Scale LLC, 871 Justin Drive, Palmyra, VA 22963
[ mike e 30scale.com ]
Peter Doolan /Angela E M Doolan, 578 Elk Mountain Road, Afton, VA, 22920
Peterdoolan&me.com ]
29 June 2020
12 Aug 2020 — Preliminary, email sent
13 Aug 2020 — complete initial review comments
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.
1. Provide SWPPP using county template.
Link to county template: httos://www.albemazle.org/home/showdocument?id=166
2. Provide PPP Exhibit that includes (as needed): rain gauge, CE, portable sanitary facility, covered dumpster,
concrete wash -out. It is possible that only concrete washout, CE, and rain gauge need to be shown.
3. Include reference to WP02020-00036 and Afton Stables in SWPPP title.
B. Pollution Prevention Plan (PPP) — See item 2 above.
The PPP content requirements can be found in County Code section 17-404.
C. Stormwater Management Plan (SWMP) — Note: comments below include ESC plan review comments.
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: SWM and ESC comments combined in this review:
1. Vicinity Map (cover of Hydraulic and Hydrological Report for Afton Stables) requires revision.
2. LOD: sheet 1 (3.55Ac.), sheet 2/VRRM.xIs (1.27 Ac., 3.38 Ac.), sheet 3 (3.38 Ac.). Please revise for
consistency. Revise VRRM.xls to report LOD.
3. Please use /rely upon the VRRM re -development worksheet for prior developed properties.
4. Provide a pre -development plan sheet that shows site prior to land disturbance covered with this
application. Title sheet Existing prior to 9.20.2017 (or appropriate date).
5. Complete redevelopment spreadsheet using prior (now existing) land cover values that total 3.38 Ac., or
3.55 Ac., whichever is accurate.
6. Provide permanent SWM facility /access easement/s to (revised) proposed SWM facilities.
7. Retitle sheet 3 Site Layout, or similar.
Engineering Review Comments
Page 2 of 5
Sheet 4
8. Maximum length of level spreader (LS) =130 lin.ft. Revise LS 1 length (142' L). Ref. VA DEQ
Stormwater Design Specification No. 2, Table 2.2. link: https://www.swbmn.vwrrc.vt.edu/wp-
content/uploads/2017/11/BMP-Spec-No-2 SHEET -FLOW vl-9 03012011.pddf
9. Ensure LS 1 outfalls to slopes that meet VA DEQ Design Specification No. 2, Table 2.2 downslope max.
gradient (%-distance).
10. Provide Ditch 1B section, if ditch design persists.
11. Show and label water protection ordinance buffer.
12. With revision, avoid ninety degree ditch intersections. In piped design, inlet shaping redirects flow, with
ditches, inertia will tend to degrade ditch walls opposite point of entry. Please provide appropriate
geometry, rip -rap class, details, etc. needed to diminish erosive impact on channel walls. Ensure design
accommodates change in direction of flow, similar to MH inlet shaping.
13. Sheet 5, Level spreaders 2 and 3 (LS2, LS3): Proposed level spreaders discharge to —12.5% and 16%
slopes, respectively. LS design must ensure sheet flow does not re -concentrate across relatively steep
slopes. Design Spec. 2, Table 2.2, though a water quality design table, specifies maximum grade required
to prevent concentrated flow downslope of an LS. Table maximum grade is 8%. LS sited above slopes of
—12.5 and 16% are likely to result in erosion of these steeper slopes, and re-channelized or concentrated
flow. Level spreaders are a viable approach to meet stormwater runoff water quantity requirements
specified at 9VAC25-870-66.D., but topography must be favorable. Please revise to meet stormwater
runoff water quantity requirements via alternate design (detention, for example). From Engineering
perspective, underground detention pipes (one/several) located near Ex. 4" PVC storm drain pipes appear a
likely useful design approach (blue -circled, below)
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14. If compost area runoff is shed roof runoff with no fecal fraction, no request to revise, but if floor of
compost area drains to 4" PVC storm drain pipe and compost includes manure, revise to avoid introducing
runoff comingled with compost into a receiving stream. Many streams in Albemarle are impaired for e-
coli. A primary function of buffers is to filter contaminants before they reach streams.
GRASS
EDGE OF
GRAVEL
Engineering Review Comments
Page 3 of 5
U Syp�
_\ QO155P
O° ppNO Ex
ST(
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DITCH 18
15. Note: If level spreaders persist in some fashion (which appears problematic), please revise Section C-C to
specify concrete level spreader material, and propose tolerance (0.001'/1' for example), since Q10 is
significant, and since level spreaders designed with pressure -treated wood, even with watertight seamless
connections at joints [seamless: means?], will degrade far quicker than concrete. Water will find outlet
through /across lowest point of a level spreader. For this development, rely on VA DEQ Design Spec. 2
Fig. 2.3, below, rather than Fig2.4A.
Level Spreader Lip
Channel /
Underdraln - 5ued
For 54c Sod
Condltbom - Dmm
Into Byrn Swale
Riparlm eurer
or FitsfYip
1 3 R Mee
5tnp of
Filter fatrnc
Appropnately 5-
Concrete footer
Figure 2.3: Plan and Cross Section of Engineered Level Spreader (ELS)
(Hathaway 2006)
16. Sheets 4, 5: Provide ESC legend (SF, CE, TS, PS, NW).
17. Sheets 4, 5: Provide, show, label VESCH measures, including: construction entrance (may be required to
access downslope areas), temporary and permanent seed -lime -fertilizer /straw mulch.
18. Sheets 3, 5: Provide label requiring removal /proper disposal of Ex. silt fence, if installed more than six
months ago.
Engineering Review Continents
Page 4 of 5
Sheet 5
19. Label WO buffer.
20. Though LS2 and LS3 may not persist as depicted, provide Q10 for eventual detention system design.
21. If LOD extends below Ex. riprap with re -design, and ex. riprap is to remain, ensure LOD accommodates
equipment /access needs required to skirt and preserve existing riprap.
22. Provide cross section, dimensions, and Qio-n- V2-y, calculations for relatively wide Ex. rip -rap channel
above LS2, and narrower Ex. rip -rap channel above LS3.
23. No SWM facilities are allowed within 100' WPO buffer. (None are, on sheet 5.)
24. Sheet 7: Planting note that reads `Owner has the option to plant Mitigation vegetation in alternate areas as
field conditions warrant so long as the plantings are located within the water protection ordinance buffer' is
problematic. This is a plan; revision to an approved plan requires Amendment, typically (arguably moreso
in this instance for ESC /SWM /Mitigation plans for land disturbance that occurred without review,
approval, permits, etc.). Please revise or edit this note.
25. Unresolved for now:
a. How to apply for or to approach DEQ for permit for past land disturbance.
b. What else Albemarle may need /require to address a past land disturbance.
c. If compliance is a proper term in context of an after -the -fact application for past land disturbance.
26. Additional review comments are possible.
27. Note: Special Exception to disturb critical slopes is not required since critical slope requirements do not
apply to agricultural buildings. See emails to Applicant: 8/7/2020 3:29 PM, 8/7/2020 3:36 PM.
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, above (Sec. Q. The erosion control plan content requirements can be
found in County Code section 17-402.
1. See SWMP: SWMP and ESCP comments combined with this review.
2. Note: follow-up ESC plan review comments, if any, may appear here.
The VSMP permit application and all plans may be digitally resubmitted for approval when all comments have been
satisfactorily addressed. Please provide digital version of revised plan /SWPPP with a completed application form.
Process:
After approval, plans will need 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 need to be completed by the owner and submitted along with cash,
certificates or sureties for the amounts specified. The agreements will need 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 need 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 need to be submitted along with court recording fees.
• If nutrient credit purchase is required (2.23 lb. purchase is proposed), purchase documents must be
executed prior to county issuance of a grading permit.
After bonding and agreements are complete, county staff will need to 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 need to be paid directly to the state. For fastest
processing, this is done electronically with the emails provided on the application (SWPPP Registration Statement).
Engineering Review Comments
Page 5 of 5
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. [ Please note review comment 25.a , above. ]
Easements must be recorded prior to VSMP plan approval, and proof of purchase of nutrient credits is required to
receive a Grading Permit.
After DEQ coverage is issued, the County can hold a pre -construction conference. Applicants must request a pre -
construction conference (complete form) and pay any remaining application fee. The form identifies the contractor
and responsible land disturber, and 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 grading permit will be issued by the County so that work
may begin.
County forms can be found on the county website under engineering applications at:
httos://www.albemarle.ore aovemment/community-develODmentlaDDIv-for/engineering-app]ications
Please Note: Albemarle County website was redesigned/relaunched 8/10/2020.
Certain links may not work —please let us know of any issues with the website.
Please feel free to call if any questions. I may be reached at 434.296-5832 -x3069
Thank you.
W 1`0202000036 Alton Stables_ VSMP OS 1320