HomeMy WebLinkAboutWPO202200005 Review Comments WPO VSMP 2022-08-12$ County of Albemarle
m COMMUNITY DEVELOPMENT DEPARTMENT
VSMP Permit Plan Review
Project title:
Castalia Farm - New Facility
Project file number:
WPO202200005
Plan preparer:
Chris Marshall [chris@shimp-engineering.com]
Owner or rep.:
Jodi Mills [jmills@stonypointdg.com]
Plan received date:
Feb. 8, 2022
April 14, 2022
June 20, 2022
July 21, 2022
Date of comments:
March 8, 2022
May 19, 2022 (Rev. 1)
July 14, 2022 (Rev. 2)
Aug. 12, 2022 (Rev. 3)
Reviewer:
David James [djames2@albemarle.org]
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/approved.
The rationale is given in the comments 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. Submit the rest of the SWPPP for review. Registration Statement received. (Rev.1)
Addressed.
2. (Rev.1) Registration statement: G. The start date should be chance-' ' ^`
Acknowledged. Please include and submit with SWPPP. (Rev.3) Addressed.
3. (Rev.3) Note: Engineering will stamp approved the SWPPP once the approved copies of
the ESC & SWM plan are inserted.
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17-404.
1. Submit for review. (Rev.1) Addressed.
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a
SWMP. This plan is denied, 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. Include owner telephone & email contact information. [17-403] (Rev.1) Addressed.
2. Sheet C5, etc. - Bioretention #3 can be moved slightly to be outside of the buffer.
(Rev.1) Addressed.
Engineering Review Comments
Page 2 of 7
3. Sheet C8 - Show existing grade lines for each profile. (Rev.1) Addressed.
4. Det. Pond: Show number and spacing of barrel antiseep collars. (Rev.1) Provide what tho
residence time says regarding seepage through embankment? Show the 4:1 phreatic line
from the design high WSE, if it intersects the downstream slope seepage control
required. See antiseep collar design for spacing requirements. (Rev.2) Addressed.
5. Bioretentions: (Ensure bioretention meets all requirements per DEQ specifications:
https://swbmpvwrrc.wp.prod.es.cloud.vt.edu/wp-content/uploads/2017/11/BM P-Spec-
No-9 BIORETENTION v1-9 03012011.pdf )
a. Ensure 2-ft minimum bottom to bedrock separation. (Rev.1) Not currently
addressed. (Rev.2) Addressed.
b. Ensure 2-ft minimum bottom to seasonal high water table separation. (Rev.1) Not
currently addressed. (Rev.2) Addressed.
c. Filter media: Please go with the 2011 standards on recommended bioretention
soil mix composition (Table 9.6). We have found that higher % of fines (clay
content) have caused issues with water filtrating though. (Rev.1) Not addressed -
Replace table 9.7 shown on sheet C7. (Rev.2) Addressed.
d. Filter media (soi/mediaJ. Ensure an infiltration rate of 2 in/hr (min). Test will be
required prior to project termination. (Rev.1/2) Acknowledged.
e. Show the underdrain (if used), cleanout and observation well locations on the
plans and profiles. (Rev.1) Acknowledged, pending test results. (Rev.2)
Addressed.
f. Provide sub -soil testing where underdrain is not used. (Rev.1) Not addressed.
(Rev.2) Addressed.
g. Provide required surface area (sq.ft). (Rev.1) Addressed.
h. Provide that the pretreatment SOD is approved as an acceptable form.
(Rev.1) Show/verify that the pre-treatment cell is at least 15% of the total
treatment volume (inclusive). Show dam or berm before entering biorientation
are, sec. 6.4. (Rev.2) Addressed.
i. (Rev.1) Provide infiltration rate of'% in/hr in order to remove drain
requirement. (Rev.2) Not currently addressed. (Rev.3) Addressed.
j. (Rev.3) Show/Provide observation well locations (6.7).
6. It appears that there is no concentrated runoff from th u, a io POA2 and
Water Quantity requirements do not apply. You would only need to size the culvert for
the upstream flow. Similar for culvert near entrance. (Rev.1) Addressed.
7. Include this checklist on the plan:
https://www.al bema rle.ore/ home/showDubl i sheddocument/3381 /637327510536700
000
(Rev.1) Addressed.
8. SWM packet: Show hatching legend for land cover maps. (Rev.1) Addressed.
9. Provide letter of availability from nutrient source provider. 0.91 TP credits currently
required according to VRRM. (Rev.1) Not currently addressed. (Rev.2) Addressed.
10. Coordinated nutrient credit agreement with Ana akilmer@albemarle.org prior to
purchase. Purchase of credits will be needed prior to bond request. (Rev.1/2)
Acknowledged. -Currently, 1.64 TPcreditsneed- (Rev.3) N/A; Acknowledged.
11. (Rev.1) Sheet C7:
Engineering Review Comments
Page 3 of 7
576.50? 60-rR = s7e.s7
AND I JbQrLWC*C. WEIR
a. Verify top of weir - - PRE-TREATMENT (Rev.2) Addressed.
b. Filter media depth needs to be 4' where trees are proposed. (Rev.2) Addressed.
12. (Rev.1) Sheet C16: Add note for bioretention tree planting area filter media to be
composed of 50/30/20 ratio mix per sec. 6.6. (Rev.2) Addressed.
13. (Rev.1) Please use the new development VRRM. I don't consider this a prior
development because the land is agriculture, nor are impervious areas (0.27ac pre-dev)
being altered (if any). (Rev.2) Addressed.
14. (Rev.1) According to VRRM there are 0.55ac of Forest/Open space that will need to be
protected post -development. This area will need to be shown and called out as Forest &
Open Space in an easement on the plans. (Rev.2/3) Acknowledged; Easement plat will
need to be approved/recorded prior to WPO plan approval.-Submitan easementp/at
application.
15. (Rev.1) Add note to Cover Sheet: "The SWM Forest and Open Space Easement is
subject to the guidance set forth by DEQ in the Virginia Stormwater Management
Program. The areas will remain undisturbed in a natural, vegetated state, except for
activities as approved by the local program authority, such as forest management,
control of invasive species, replanting and revegetating, passive recreation (e.g., trails),
and limited bush hogging to maintain desired vegetative community (but no more than
four times a vear)." (Rev.2) Addressed.
16. (Rev.2/3) Record SWM maintenance agreement.
D. Mitigation Plan (MP)
The mitigation plan requirements can be found in County Code Chapter 17-406.
1. Submit a mitigation plan for proposed disturbance in the stream buffers. (Rev.1)
Addressed.
2. Provide culvert calcs and size them to pass the 25-yr storm. (Rev.1) Addressed.
3. For crossings of perennial streams, bridges, arch culverts, or box culverts shall be used.
(Rev.1) Acknowledged.
4. The stream crossing shall not disturb more than 30 I-ft. It appears you exceed this
amount at the second crossing. (Rev.1) I'll will see what Frank says. Did not get a
response in time for review. (Rev.2) Acknowledged. It appears the crossing is
minimizing stream disturbance to 60 I-ft and is allowed.
5. Add note to mitigation plan that stream bed and banks shall be stabilized within (7) days
from start of backfilling and to notify inspector. (Rev.1) Addressed.
6. Provide copy of approved permit from USACE for the stream crossings. (Rev.1)
Acknowledged. I would need some sort of confirmation from USACE that permitting is
not required. (Rev.2) Acknowledged. (Rev.3) Provide copy of NW permit. Sec. 17-604C.
6. Evidence of required permits.
7. Show the design for a single stream crossing. Provide justification for two stream
crossings. [17-604 C][17-406 A.3] (Rev.1) It's the access road (# of crossings) to be able
to use the lot. The proposed parking is not in violation of Zoning ordinance and it was
Engineering Review Comments
Page 4 of 7
determined the access road is allowed.
8. (Rev.1) Provide mitigation to stream buffer areas first and foremost; then, provide to
areas outside of stream buffer. Areas outside of buffer will need to be shown in a
mitigation or conservation easement. (Rev.2) Partially addressed. Double check the
buffer amount disturbed. You can also reclaim buffer that are overgrown with invasives
and/or with dying/diseased trees so long as areas are identified out in the field. Areas
-utside the buffer will need to be protected in a conservation easement. (Rev.3)
Acknowledged.
E. 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.
i. Cover: Provide date(s) when site boundary and topography survey was performed.
(Rev.1) Addressed.
2. Show VDOT entrance tvoe. VDOT entrance permit will need to be obtained prior to
permit issuance (Rev.1/2/3) Acknowledged.
3. Sheet C9/10A
a. Show existing drainage divides. (Rev.1/2) Not addressed. (Rev.3) Addressed.
b. Show SC (VAESC HB, Spec. 3.24) for the stream crossings. (Rev.1) Addressed.
c. Provide VSS, SSS (VAESC HB, Spec. 3.22, 3.23) as necessary. (Rev.1) Addressed.
d. Tie-in proposed grading for traps. (Rev.1) Addressed.
e. Show drainage area to diversions (5ac max). (Rev.1) Acknowledged; Update the
legend key for DV & remove DD. (Rev.2) Addressed.
Ensure channel diversion directional change is not too severe & greater than 90
degrees. Energy dissipation check dams can be implemented. (Rev.1) Partially
addressed. This area needs to be corrected for a number of reasons. (Rev.2)
i
IMITS OF DISTURBANCE _
s9
c,. (Rev.3) Addressed.
Engineering Review Comments
Page 5 of 7
g. (Rev.1) RWD should be shown on E&S ph2 instead once the access is graded.
(Rev.2) Not addressed. (Rev.3) Addressed.
h. (Rev.1) Show a staging and stockpile location. Show SF around stockpile. (Rev.2)
Not addressed. (Rev.3) Addressed.
i. (Rev.1) Provide the channel design for the diversions as well, including CWD.
Show the drainage area maps, cross-section dimensions, 2-yr & 10-yr WSE, and
appropriate liner type needed. (Rev.2) Not addressed. (Rev.3) Addressed.
j. (Rev.1) ST#4 detail needed? (Rev.2) Not addressed. (Rev.3) Addressed.
4. Sheet C12, etc. -
a. Conversion to permanent facility/BMP shall not occur until the road and all
upstream drainage areas are fully stabilized. This would be after #12 in the phase
2 sequence. (Rev.1) Clarify and label SWM facilities. Conversion to bioretention
shall not happen until all upstream areas are fully stabilized. You can provide the
grading necessary, but it will still function as a trap must meet volume
requirements and must be cleaned out prior to conversion. (Rev.2) Partially
addressed. Revise the Sequence of Construction to match what you're stating.
(Rev.3) Addressed.
b. Show SF here & provide B/M on slope:
1
I AC
1
(Rev.1) Acknowledgerl- --- ' ^ `-
(Rev.2) Addresser
c. (Rev.3) C11: Provide diversion (DV) with rock check dams to receiving channel. -
Similar solution in addressing comment If
ST
\v�
\
l
2 \
A A
DISTURBANCE = 11.66 AC
Engineering Review Comments
Page 6 of 7
5. Sheet C12 should still be showing ESC sediment traps and not the permanent SWM
features in place. (Rev.1) SWM facilities should be only shown on SWM plan, unless
protected and offline. (Rev.2) Partially addressed. Revise the Sequence of Construction
to match what you're stating. (Rev.3) Addressed.
6. Provide the liner type requirement for the channel conveyances. (Rev.1) Addressed.
7. (Rev.1) Sheets C3, C9-C12: Show all critical slopes (typ. shaded). Existing critical slopes
are not to be disturbed, unless a waiver or exemption has been granted. 18-4.2, 14-304
(Rev.2) Per email - A small hatch of critical slope is not shown... (Rev.3) Addressed.
8. (Rev.1) Sheet C4: Grading next to stream buffer appears to be in critical slopes but will
need to verify. Exception not allowed for drainageways if within. Provide alternate
alignment. 18-4.2.6 (Rev.2) Acknowledged. Will need to verify.
/ of
(Rev.3) Addressed.
9. (Rev.1) Sheets C11-14: Please label or callout the sediment traps, bioretentions, and
basins for ease of identification and to follow construction sequence (ST#1, Basin #3,
etc). (Rev.2) Addressed.
10. (Rev.1) Sheets C11/12:
a. Reduce grading to under 2:1. (Rev.2) Addressed.
11.
12.
WITS OF
b. Show TS/PS & MU for constructed slopes adjacent to road ditches. (Rev.2)
Addressed.
Zev.2) C3, etc.: Please show the existing contour el--ti (Rev.3) Addressed.
Zev.2) C11-14: Revise - Scale appears to be V=. (Rev.3) Addressed.
The VSMP permit application and all plans may be resubmitted for approval when all comments
Engineering Review Comments
Page 7 of 7
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, erosion and sediment control and stormwater management improvements must
be bonded. The bonding process begins when the plan is approved, and the applicant submits a
bond estimate request form and fee to the Department of Community Development. A plan
reviewer 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 to the
County, who will record the agreement.
After bonding and agreements are complete, county staff enters project information in a DEQ
database for state application processing, if a DEQ permit is required. DEQ reviews 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, which must be posted at the construction site.
After DEQ coverage is issued, via the coverage letter, the County can hold a pre -construction
conference. Applicants must 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;
https://www.albemarle.org/govern ment/community-development/apply-for/engineeri ng-applications