HomeMy WebLinkAboutWPO201500025 Review Comments WPO VSMP 2015-06-04�pF A
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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:
Reviewers:
VSMP Permit plan review
CMA Properties
WP0201500025
Collins Engineering
CMA PROPERTIES INC
20 April 2015
4 Jun 2015
Max Greene, Michelle Roberge
[email]
[pborches @cmacars. c om]
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 ESCP, (3) a SWMP, and (4) any TMDL measures necessary.
1. A.Clarify the approved permit from DEQ. A permit is granted for an approved VSMP plan. Is this an
amendment to an approved plan.
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17 -404.
1) The PPP should be labeled Pollution Prevention Plan and not just another copy of the E &S
plan. Include an 11 "x 17" Pollution Prevention Plan map showing concrete washout, porta-
johns, fueling stations, and trash containers. This will be marked up by the contractor as
construction of site progresses.
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. Clarify the SWM note on title sheet. It does not match proposed BMP.
2. It appears the bioretention will be built to be fully operational for phase 1. When phase 11 is
proposed, the sediment basin 1 will no longer be available. What erosion control measure will be
used then?
3. On sheet 6, the drainage area A is noted as 3.27 acres. State the project site acreage on the
Engineering Review Comments
Page 2 of 4
predevelopment inset (5.2 acres ?). It's confusing to label the predeveloped site 3.27 acres. This
project site area 5.2 acres can be used for the predevelopment acreage on the VRRM. Note the
existing parking lot needs a 20% phosphorous load improvement from the pre developed
phosphorous load.
4. On sheet 6, remove the combined phase I & II information. Only show phase I. It is important to
note that you are showing more than 12" of ponding for Phase II, which needs to be addressed.
This is where more runoff reduction or detention on site is needed like we discussed during the
ZMA.
5. On sheet 6, what is the minimum treatment volume referring to? Verify how that was calculated.
6. Clarify treatment volume shown on phase 1 and phase I & 11(37,686 cf). The TvBMP is the
treatment volume based on the contributing drainage area to the BMP, TvDA, plus any remaining
runoff volume discharged from upstream BMPs in the treatment train. The treatment volume
includes the volume in the surface ponding, filter media,and 12" gravel. Note this may change
with maximum 12" ponding.
7. Use the 1.10 acres for pre - developed impervious area from the approved ZMA.
8. Use .19 acres for open space (bioretention) in drainage area A. The terraced wall/benching should
not be included.
9. Provide some sheets in VRRM that are legible.
10. The riser structure is incorrectly labeled as 15 ". Change to 24 ".
11. Where is the planting schedule? Show plan view for bioretention plants. Plants selection for 12"
ponding should be looked into.
12. Show 12" gravel under underdrain. Show in profile on sheet 7.
13. Clarify the areas that would need 1:1 side slopes for filter media rather than placing a note.
14. Is there a defined channel for emergency spillway?
15. On sheet 7, show landscaping buffer as note calls out one.
16. Verify where the forebay gabion design is from.
17. Provide the outlet protection design.
18. There is a proposed easement beyond outlet protection. Provide.
19. Remove the "level 2 minimum 36" note from bioretention detail.
20. Show geotextile fabric around in basin. See standard.
A 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, 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. Basin
a. Phase 1,
i. Basin does not appear to capture the existing swale in the rear of the site. Please
add a diversion or extend the basin over the swale. The 400 feet of drainage
swale exceeds the protective ability of the proposed silt fence that T -bones the
swale.
ii. Basin does not appear to capture the existing swale in the front of the site. The
front of the site has a smaller swale ( @200 feet long) with a diversion that bucks
grade into the basin. Please extend the basin to capture this swale, or a better
design for the diversion that does not appear to force stormwater uphill into basin.
b. Phase 2,
i. Diversion is needed in back of site to help direct stormwater flows into basin after
pipe is installed. Please show the grading for the diversion. (See Std. & Spec.
Engineering Review Comments
Page 3 of 4
3.12, design criteria, page III -66)
ii. Front swale will need to be shown graded into the proposed contours due to
proximity to property line. Temporary grading easement may be required from
adjacent property owner in order to actually construct slope and diversion in
location as shown. (See Std. & Spec. 3.12, design criteria, page III -66)
c. Emergency spillway,
i. 60' spillway length seems excessive, contractor will have a difficult time
constructing a spillway that equally distributes basin overflow across what is
basically a 60' level spreader.
ii. Please show armoring of the spillway and state on the plans that the emergency
spillway must be constructed in a manner that allows the basin overflow to equally
utilize the entire length of the spillway.
d. Due to the unusual geometry of the basin design, the inspectors are not able to verify plan
compliance and an as -built survey will be required upon completion of the sediment basin.
The as -built survey verification will be added to the SWPPP for review.
2. Please show the existing topography at least 50' past the property line and/or limits of disturbance
for a better understanding of the neighboring drainage patterns. Additional comments may arise
from missing information.
3. Inlet protection should be shown on all inlets along Berkmar Drive that site may drain into.
Appears there might be 3 inlets that will need protection.
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;
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.
Engineering Review Comments
Page 4 of 4
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;
hltp://www.albemarle.org/deptfonns.asp?department--cdengWpo
File: E1_vsmp_ review projectname.doc