HomeMy WebLinkAboutWPO201400094 Review Comments WPO VSMP 2014-12-11� OF AL
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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project title:
Project file number:
Plan preparer:
Owner or rep.:
Plan received date:
Date of comments:
Reviewer:
VSMP Permit Plan Review
Whittington — Phase B
WPO- 2014 -00094
Dominion Engineering & Design, LLC
Stanley Martin Homes
14 November 2014
11 December 2014
Justin Deel
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. The
rationale is given in the comments below. The application may be resubmitted for approval if all
of the items below are satisfactorily addressed. 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 ESOP, (3) a SWMP, and (4) any TMDL measures necessary.
1. Please use the standard template from the County website. You are presenting this as a revision to
expand an existing SWPPP. Your registration statement was for 184.1 acres, 75.4 of which was
disturbed. The new plans indicate phase A was 29.9 acres and phase B is 154 acres. Please clarify
the actual acreage disturbed, and all acreages on the documents. Please incorporate the active
SWPPP document, which this will replace in large part.
2. Include only items in template and /or County Code Section 17 -405.
3. Provide any necessary TMDL measures.
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17 -404.
1. Please address all items listed in section 17 -404 of the County Code.
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.
It is unclear to us, and warrants further discussion, as to how your proposed stormwater
management plan stays within the approved ZMA plan. This may not be essential for the
grandfathering provisions in the state code, as DEQ already issued a permit for this activity.
However, the stormwater management needs to meet the IIC criteria, and at least provide the
coverage intent of the approved ZMA plan. There do not appear to be enough of the roadways and
houses captured by treatment. The original plan showed rain gardens in the cul -de -sacs and
Engineering Review Comments
Page 2 of 4
intersections, and large ponds, with the intent to capture all of the roads, and the majority of lots
central to the development. The new plan leaves large stretches of road and lots untreated, with
grading that is problematic in providing permanent capture to the BMP facilities. Please revise to
provide follow the natural drainage of the topography. Coordinate to provide adequate sediment
trapping for erosion and sediment control, along natural topography, outside limits of final lot and
road grading, and coordinated for conversion to permanent stormwater management.
2. Please provide proposed mapping and plans, showing drainage areas for proposed stormwater
management facilities, at a legible scale (preferably at least 1" = 50').
3. Show stream/wetlands buffer at SWM- 3 /SB -1 and add mitigation accordingly.
4. Provide sediment forebays in all SWM facilities [VSMH Vol. 1, 3.04].
5. Provide measures to avoid short - circuiting in SWM -3 and SWM -7 [VSMH Vol. 1, 3.06- 12 -13].
The basins should meet the flow and shape design parameters. (Baffles should not be a part of
permanent designs.)
6. Provide facility access per VSMH Vol. 1, 3.06 -18.
7. Existing topography is not labeled on some SWM facility details, please correct.
8. Show accurate existing topography for SWM -4.
9. Provide scaled cross sections for SWM facilities, including biofilters, in place of old typical details
(E43).
10. Please remove Proffered Overlot Grading Plans. They appear to be largely redundant in this plan
set. Grades should be shown anyway as part of an E &S /SWM plan package. The overlot grading
plan is a zoning requirement as part of the proffers, which are not enforced through the VSMP
program.
11. The County BMP spreadsheet is no longer acceptable. Designs must follow the state IIC or IIB
criteria.
D. Erosion and Sediment Control Plan (ESOP)
Virginia Code §62.1- 44.15:55 requires the VESCP authority to approve or disapprove an ESOP.
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 explain how your phasing plan (E3) will be implemented. It appears as though the
installation of the sanitary sewer line will warrant E &SC measures that will not occur until
subsequent phases.
2. Mitigation for disturbance to stream buffers should occur within the affected stream buffer, please
correct [Albemarle Co. Code 17 -604 C.5]. Mitigation can occur in other stream buffer areas, but
mitigation is not valid outside stream buffers unless it is additional stormwater treatment for
discharging into buffers.
3. Your wetlands report shows a wetland in the areas of SB -1 and SB -3. Please provide a stream
buffer for these areas and include in your mitigation plan.
4. Grading for SB -3 affects a stream/wetland that is not within your stream buffer. Please explain
why this is not included in the buffer.
5. Please explain why the northwesternmost stream on the property is excluded from your shown
stream buffer.
6. Please adjust your limits of disturbance to include all affected areas, not just the areas that are to be
graded.
7. Provide staging /stockpile area(s).
8. Show dust control and temporary /permanent stabilization.
9. Please do not show silt fencing going down/up hill. Silt fencing should be "stepped down ".
10. Silt fencing should not be used in place of diversion dikes. Please provide diversion dikes and/or
sediment traps where needed (Ex.: the silt fence traversing the southern portion of Sheet E21).
11. Provide legible drainage areas on E &SC plans. The provided drainage area maps are unclear and
Engineering Review Comments
Page 3 of 4
several are unrealistic (Ex.: Drainage area for ST -12).
12. Please show topography for the entire drainage area at ST -16. It appears as though the ridgeline
may be beyond your drainage area.
13. Culvert designations vary on E &SC plans and drainage plan (E31), please correct.
14. Please show realistic shapes for sediment traps and basins (Ex.: ST -1).
15. Provide a construction entrance that drains to a sediment trap or basin [VESC Handbook, 3.02].
16. Show critical slopes on E &SC plans.
17. Show proposed Phase 1 topography as existing topography on Phase 2 plans. Ideally, phase A/1
areas are already graded, and topography should be resurveyed in these areas.
18. Show existing topography for Phase A.
19. Please provide an explanation for your "Phasing Plan ", Sheet E3.
20. Include proposed sediment basin at Phase B entrance in your limits of disturbance. Please show
existing topography and provide a designation for this basin.
21. Provide detail for CWD, these are not a part of the VESC Handbook.
22. The CWD above the cut on Sheet E14 should follow limits of disturbance to avoid high velocity
flow into wetland, please adjust.
23. Anywhere silt fence or diversions are coming to a point at a natural drainage low spot, a sediment
trap or basin must be provided. As an example, provide a sediment trap for the fill slope between
STA 21 +00 and 20 +00 on Sheet E5.
24. Provide sediment trapping measure in front of Lot 26.
25. Provide more effective E &SC measures at stream crossings.
26. Provide a sediment trap for the fill slope at the end of Kentra St., Phase 1.
27. Show how drainage on Sheet E12 will reach ST -7.
28. Please show access easement for Singleton Lane.
29. Provide scaled details (sections) for basins.
30. Please clarify what you are proposing at ST -14, Phase 2.
31. Please provide adequate E &SC measures to protect WPO buffer. More than silt fencing will be
required to protect WPO buffer in many areas.
32. Provide E &SC measures, other than silt fencing, beneath fill slopes east of Kendra St., especially
lot 39.
33. Ensure that all sediment basins outfall into an adequate channel.
34. Is ST -13 not included in Phase 2? It appears as though it is needed and is included in Phase 2
drainage area map, but not in Phase 2 plan.
35. Please make sure all existing and proposed contours are labeled on all plan sheets (Ex.: Proposed
contours on Sheet E13 are not labeled, existing and/or proposed contours are not labeled on many
of the sediment basin/trap details.
36. Further, please ensure that all structures and embankments match permanent design for facilities to
be converted to permanent stormwater management facilities.
37. Diversion dike cannot go through home lots. As stated in the stormwater management comments,
please ensure all protection measures are outside lot and road grading where ongoing maintenance
is not possible. Perimeter protections must be on the perimeter.
38. Silt fence alone is not adequate enough on and around Lot 28, please correct.
The VSMP permit application and all plans may be resubmitted for approval when all comments have
been satisfactorily addressed. For re- submittals please provide 2 copies of the complete permit package
with a completed application form.
Engineering plan review staff are available from 2 -4 PM on Thursdays, should you require a meeting to
discuss this review.
Process;
Engineering Review Comments
Page 4 of 4
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 2 -4 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.
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. 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 will need to 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. 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;
http://www.albemarle.org/deptforms.asp?department=cden.gwpo
File: Whittington Phase B WP0201400094.doc