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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:
Rocky Hollow - WP0201400075
Plan preparer:
Morgan Bell [ Morgan n,shimp- engineering com ]; Justin Shimp, Shimp
Engineering morgan [201 E Main St., Suite M, Charlottesville, VA 22902-
5273 - justinAshimp -en ineering com ]
Owner or rep.:
Adriana K. Tuerk, Trustee of the Adriana K. Tuerk Living Trust [P.O. Box 85,
Isla, FL 33036]
Plan received date:
29 August 2014
(Rev. 1)
23 October 2014
Date of comments:
1 October 2014
(Rev. 1)
4 November 2014
Reviewer:
John Anderson
A. Stormwater Pollution Prevention Plan
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. Furnish SWPPP /PPP —focus on land disturbance. Please use 8 -p. SINGLE- FAMILY STORMwATER
POLLUTION PREVENTION PLAN TEMPLATE found at VDEQ Construction General Permit website: link -
httn: / /www.dea.virainia.aov /Portals /0 /DEO /Water /StormwaterManaaement /CPoD SWPPP SFR
201407.docx.E (Rev. 1) Comment partially addressed. As follow -up, please ensure that
Construction Activity Operator matches Construction Activity Operator on General VPDES Permit
Registration statement. Ensure all pages requiring signature are signed by Operator.
2. Submit a General VPDES Permit Registration Statement — please ensure that statement is signed.
Please ensure that Item 9, Estimated Area to be Disturbed is consistent with ESC plan (1.91 ac.).
B. VSMP: SWPPP: Stormwater Management Plan
VSMP Regulation 9VAC25- 870 -108 requires the VSMP authority to approve or disapprove a SWMP. This plan
is disapproved for reasons provided in comments below. The stormwater management plan content requirements
can be found in County Code section 17 -403.
1. Submit VSMP Application/SWM plan. Application form may be found on County website, Engineering
Applications and Forms (last .pdf) —fee based upon total area of disturbance (1.91 Ac.) Note: project is
subject to SWM requirements since disturbance >1.0 Ac. [§17-303.C.] Although code makes provision for
Agreement in lieu of a stormwater management plan (§ 17- 403.B.), definition of Agreement in lieu of a
stormwater management plan (§ 17 -205) implies compliance with requirements of the VSMP. Relief or
exceptions from the requirements of the VSMP (§ 17 -408) appear so limited as to be of negligible benefit.
(Rev. 1) Comment addressed. SWM and Mitigation plans combined: sheet dated 10/21/14. As follow -
up, if 30' wooded buffer =2.94 Ac. is to be used for SWM compliance, ensure permanent conservation
easement preserves this 30' buffer. Also, please reconcile wooded area =2.94 Ac. with 7.41 Ac. (post -
developed) forest area, Drainage Area `A'(.xls submitted 10/22; ref. #2, below), if preservation is an
element of SWM runoff reduction water quality (phosphorus) compliance.
2. This is new development: please use VaRRM New Development spreadsheet — link:
htW: / /www.deq.virizinia. aov/ Portals /0 /DEQ/ Water/ StormwaterManaaementNRRM /VRRM_Spreadsheets_
Engineering Review Comments
Page 2 of 4
v2.8_2013.zip (Rev. 1) Comment addressed. As follow -up to VaRRM .xls sent as email attachment
(Wed 10/22/2014 4:45 PM), please provide permanent conservation easement protection for 7.41 Ac. of
forest (elsewhere on property). Alternatively, adjust BMP practices such that compliance does not rely on
permanent forest conservation easement.
3. Furnish SWM Narrative. (Rev. 1) Comment addressed.
Note: May elect to control runoff at any point or location on developed property, including near residence.
Also —VSMP Registration Statement is not required. [§ 17 -40 LC] (Rev. 1) Note is in error: VSMP
Registration statement is required. Please complete Registration Statement. —Also, SWPPP, A.2., above.
C. VSMP: SWPPP: Erosion Control Plan
Virginia Code §62.1- 44.15:55 requires the VESCP authority to approve or disapprove an ESCP. This plan is disapproved
for minor reasons provided in comments below. The erosion control plan content requirements can be found in County
Code section 17 -402.
1. C2 — Expand project description to include: drive length; critical slope disturbance (sf); stream
buffer disturbance (14,756 sf); and any alternative driveway alignments considered. -§17-402.C.5.
(Rev. 1) Comment addressed.
2. C2 — Sequence: describe provisions for stream bypass, or work in live stream. Note: Obtain state -
federal permits to work in live stream. — Sequence, Stage 1, item #3 — requires detailed narrative.
(Rev. 1) Comment addressed.
3. C3 — Clarify /specify grading improvements to existing logging road, slope 13.5 %. (Rev. 1)
Comment addressed.
4. C3 —Show spoils and stockpile locations, if any. (Rev. 1) Comment addressed.
5. C3 —Show staging area; equipment maintenance /refueling location. (Rev. 1) Comment
addressed.
6. C3 — Identify /show stream buffer mitigation area: possibility exists west of driveway along stream
where GIS photometric data shows reach with minimal buffer. (On sheet C3, area near soil label
79B that is adjacent to soil area 89B is one possible location.) (Rev. 1) Comment partially
addressed. As follow -up, identify additional areas (within stream buffer elsewhere on property)
suitable for mitigation plantings. —Also, #23 -24, below.
7. C4 — Show /shade critical slope areas. Areas shown on C3, but please transfer to 1 " =10' view, C4.
(Rev. 1) Comment partially addressed — printing caused light hatch to fade. Light hatch is not
visible. Ensure critical slopes are visible on C4.
8. C4 —Label outlet protection L X W X D dimensions (OP). (Rev. 1) Comment addressed.
9. C4 — Furnish driveway culvert near box culvert to divert ditch flow from stream to SWM BMP.
(Rev. 1) Comment addressed.
10. C4 — Furnish SF on graded slopes at box culvert outfall to limit sediment deposition in stream.
(Rev. 1) Comment addressed.
11. C4 —Show 100' stream buffer. (Rev. 1) Comment partially addressed. As follow -up,
recommend heavier line weight, sheet C4 /ESCP. Show stream buffer on SWM Plan, Cl.
12. C4 —Show wood /forest line. (Rev. 1) Apparent printing error, please show or note wood line.
13. C4 —Show or define angle of each wing wall relative to box culvert. (Rev. 1) Comment
addressed.
14. C4 — Recommend aprons, box culvert, given site /stream conditions. [VDOT Drainage Manual,
8.3.3.4.6] Troy Austin, VDOT, may be able to provide guidance /assistance: 434.422 -9373. (Rev.
1) Comment addressed. Design response noted: "based on channel conditions and the Drainage
Manual, we believe that an apron is not necessary." (SE response letter, 21- Oct -14)
15. C4 — Identify ESC feature south of driveway -brick symbol = riprap ditch? (Rev. 1) Comment
addressed.
16. C4 — Provide /specify ground cover hardier than grass for slopes steeper than 3:1. [ACDSM 8.A.2.]
(Rev. 1) Comment addressed.
17. C4 — Furnish EC -1 stabilization matting for slopes at wing walls at outlet end of box culvert. (Rev.
1) Comment addressed — review error: mixed terms. As discussed 3 -Nov with Justin, SE decision
Engineering Review Comments
Page 3 of 4
to use EC -1 (stone) offers slope stabilization superior to EC -2 matting.
18. C5 - Furnish box culvert wall, floor, ceiling dimensions. Provide steel reinforcement schedule, or
specify pre -cast system. (Rev. 1) Comment partially addressed, perhaps misinterpreted. Please
furnish box culvert wall, floor, and ceiling thickness. Furnish steel reinforcement for structure:
walls, floor, and ceiling. Details integral to design of box culvert should be shown [§ 17- 102.A.].
19. C5 - Driveway section: identify surface material; identify base material. Show dimensions /depth.
(Rev. 1) Comment addressed.
20. C5 - Furnish cross - section of stream bed at box inlet: stream bed elevation affects countersinking,
which affects free height. [§ 17- 402.C.5; Drainage Manual, 8.3.7.2.2]. Estimate /show OHW at
box culvert inlet, and stream width. (Rev. 1) Comment partially addressed - please check
location/elevation of 10 -year storm line, sheet C5, culvert profile.
21. C5 - Confirm box culvert design per VDOT Drainage Manual 8.3.7.2.3 - "determine the required
hydraulic opening (size) based on no countersinking; then specify the next larger size structure."
And, Drainage Manual, Ch. 15, DDM 1 -6: Summary of General Design Criteria. (Rev. 1)
Comment addressed.
22. Furnish Foundation Investigation: "Foundation data will be requested for all culvert installations
with a diameter or span of 36 inches or greater." [VDOT Drainage Manual, Ch. 15, DDM 1 -13]
(Rev. 1) Comment addressed. Design response noted: "Foundation notes have been added to
sheet C5. Based on standard assumptions for native soil in the area, it [streambed] should be able
to withstand the weights of the box culvert and driveway." (SE response letter, 21- Oct -14)
New:
a. Space constraints limit length of construction entrance; CE should not extend beyond
stream. Revise length.
D. VSMP: Mitigation Plan
- The mitigation plan requirements can be found in County Code section 17 -406.
23. Furnish mitigation plan. Identify potential candidate stream buffer mitigation areas on property,
ideally, within 100' of stream. (Rev. 1) Comment partially addressed. As follow -up, ensure
stream buffer impact is reported consistently (14,756 sf, C4, v. 15,660 sf- Mitigation Plan). Also,
please note 2:1 mitigation -to- replanting requirement (ref. email -Mon 11/3/2014 3:10 PM).
24. Furnish mitigation planting schedule- options, below: (Rev. 1) Comment partially addressed -
As follow -up, see #23, above.
1. Option 1 — Mitigate through new plantings and permanent protection as given
below. New plantings must be in the stream buffer area. Applicant has choice of
planting one of the following:
a. For every 400 square foot unit or fraction thereof, plant one (1) canopy tree
measuring 1 W"— 2" caliper or a large evergreen 6 feet in height, one (1)
understory tree measuring W'— 1 V2z caliper or one evergreen 4 feet in height,
and one (1) small shrub 15" — 18" in height.
b. For every acre or fraction thereof, plant 1,210 hardwood and/or pine seedlings
on approximately 6'X6' centers without tree tubes and mats.
c, For every acre or fraction thereof, plant 600 hardwood and/or pine seedlings
on approximately 8'X8' centers with tree tubes and mats.
2. Option 2 — Mitigate by preserving existing buffer where currently not required by
ordinance; i.e. preserve stream buffers on intermittent streams in the development
areas. Mitigation must be accomplished by permanent protections as given
below.
Permanent Protection for each of these options will be inclusion in the Thomas
Jefferson Soil and Water Conservation District (TJSWCD) Easement Program, or
recordation of a permanent maintenance agreement and escrow to run with the
land.
The VSMP permit application and all plans may be resubmitted for approval when all comments have been
Engineering Review Comments
Page 4 of 4
satisfactorily addressed. For re- submittals please provide 2 copies of the complete permit package with a completed
application form.
Engineering plan review staff is available from 2 -4 PM on Thursdays, should you require a meeting to discuss this
review. Plan reviewer is available at 434 - 296 -5832 -0069 should you have any questions.
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.
After DEQ coverage is issued, via the coverage letter, the County can hold a pre - construction conference. Applicants
will need to request a pre - construction conference by completing a 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;
htt2://www.albemarle.ora/deptforms.asp?departynent--cdengmMo
WP0201400075 -rocky hollow escp -pvt residence - 110414 -revl