HomeMy WebLinkAboutWPO202000039 Review Comments WPO VSMP 2021-03-09t� OF ALB
$ County of Albemarle
COMMUNITY DEVELOPMENT DEPARTMENT
�tBGIN�P'
VSMP Permit Plan Review
401 McIntire Road, North Wing
Charlottesville, VA 22902-4579
Telephone:434-296-5832
WWW.ALBEMARLE.ORG
Project title:
Crozet Elementary School Addition, Renovation and Site Improvements—VSMP
Project file#:
WPO2020-00039
Plan preparer:
Kim Mellon /Timmons Group [ kim.mellon(d�timmons.com ]
Bryan Cichocki, PE, bryan.cichocki(a),timmons.com
608 Preston Ave., Suite 200 / Charlottesville, VA 22903
Owner or rep.:
Albemarle School Board, Atm. Superintendent
COB, 401 McIntire Road, Charlottesville, VA 22902
Matt Wertman, Sr. Project Manager, FES /FPC
mwertman@albemarle.org
Plan received date:
10 Aug 2020
(Rev. 1)
7 Dec 2020
(Rev. 2)
5 Feb 2021
Date of comments:
23 Sep 2020
(Rev. 1)
17 Dec 2020
(Rev. 2)
9 Mar 2021; 1 item remains ( SWM Plan review item Td.)
Reviewer:
John Anderson
Note: If ( initial) review comment text grayscale, then comment addressed with Rev. 1, or 2.
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 in 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. Revise to include ref. to WPO202000039 in title. (Rev. 1) Addressed.
2. Sec. 1, Registration Statement, is [Rev. 2 `substantially'] blank. Complete with care. Additional comments
possible. (Rev. 2) Not addressed.
3. Sec. 3, Nature of Activity references construction dates as indicated on the Registration Statement. No
dates listed on Registration Statement. (Rev. 1) Partially addressed. As follow-up: Albemarle relies on
registration statement details to register projects with DEQ. Dates need to be expressed in M "D/YYYY
format for transfer to the state database. Please provide dates in M-D-Y format, not spring /fall. (Rev. 2)
Not addressed. Provide estimated project dates on Registration Statement, Sec. II.G.
4. Sec. 4, 5: Update once all ESC /SWM-related review comments addressed. (Rev. 1, 2) Persists. Asfollow-
Up: 1 review item remains, please see SWM plan review item 7.d.
5. Sec. 6.A.: SWPPP does not appear to include I I" x 17" SWPPP Exhibit. Provide exhibit that shows:
a. Rain gauge
b. Non -hazardous solid waste dumpster, with cover
c. Portable sanitary facility ( porta-john)
d. Solvent -chemical -paint storage
e. Concrete /stucco washout
f Paved construction entrance, draining to trapping measure
Engineering Review Comments
Page 2 of 8
g. On -site fuel storage containment, as required by site contractor [better to show and not need, than
not to show], design secondary, impermeable lined containment (10ml plastic -lined) sized to hold
[stored Vol. of fuel + 10-yr. storm event let)] x 1.1.
6. Sec. 6.E.: The SWPPP cannot be approved until named individual responsible for PPP is identified. The
VSMP cannot be approved unless SWPPP is approved. A VAR10 permit cannot be requested until the
VSMP plan is approved. A grading permit cannot be issued until the VAR10 permit is issued by DEQ.
(Rev. 1) Not addressed. Listed as MD but may wait till just prior to preconstruction meeting. (Rev. 2)
Addressed.
7. Sec. 8, Qualified Personnel: Similar to item 6., SWPPP cannot be approved until named individual is listed
as qualified inspector. (Rev. 1) Not addressed. Listed as TBD but may wait till prior to preconstruction.
(Rev. 2) Addressed.
8. Sec. 9, Signed Certification: Please sign. (Rev. 1) Not addressed. Please sign with next submittal. (Rev.
2) Addressed.
9. Sec. 12, Inspection Logs, Inspection frequency: 2019 VAR 10 inspection frequency differs from 2014 VAR
10, slightly. Please revise inspection frequency text consistent with 2019 VAR10, Part II.G.2.a.1./2.; link:
https://www.dea.virginia. gov/Portals/O/DEQiWater/StormwaterManagement/CGP%20ADA/CGP2019.ndf
?ver--2019-05-06-131630-407 (Rev. 1) Partially addressed. As follow-up, please delete item (2), p. 82,
SWPPP, and revise to text at 2019 VAR10 Part II.15.2.a.2, to .oad� a eFbatim: CGP text deleted with Rev. 2
comments. (Rev. 2) Addressed.
10. New: Note: Effective Jan-1 2021, DEQ requires local programs to transition to a new Registration Form.
This project may require the new form if the WPO Plan is not approved by 12/31/20. This comment alerts
and notifies of new registration requirements. From DEQ email (12/9/2020 11:00 AM), ^a-'i�:
[text deleted with Rev. 2 comments] (Rev. 2) Addressed.
B. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP.
This plan is disapproved for single reason listed, below (item 7.d.. The stormwater management plan
content requirements can be found in County Code section 17-403.
1. Design Calculations and Narrative- Aug-10, 2020:
a. Revise cover to include ref, to WP0202000039,
b. Pg. 3: Revise Water Quality Narrative to include ref to proposed new bioretention facilities.
c. Pg. 5-6: Include pipes 501 and 505 in VDOT LD-229 Storm Sewer Design Computation Table.
(Rev. 1) Partially addressed. As follow- Table, C7.2, intends to show culvert adequacy, but is
unclear. Please revise table to include headings that aid ease of comparison of post -developed Qio-
, Q25- with Ex. culvert capacity. Please alert if data presented elsewhere was overlooked. (Rev. 2)
Addressed.
Culvert calculations
C04
Ma
Im Mnsenbn
Q25
.4
022
6.47
7
15
0.16505
Ex Culvel
0.531
0.361
0.141
0.231
0.191
6.47
.Q10
731
1.24
1.40
501
0.58
0.97
0.46
Q51
0.569
6.47
7.31
3.68
4.16
d. Include Ex. storm pipe at Ex. central /main elementary school entrance. Assign ID to this pipe.
(Rev. 1) Partially addressed. As follow- Please see item Lc above. (Rev. 2) Addressed.
e. Ensure Ex. main entrance storm pipe conveys Qlo-Yr without flooding (Note: Ex. pipe is 15" DIA
while proposed upstream pipe 505 is 18" DIA (both 501 and 505 are 18" DIA). (Rev. 1) Partially
addressed. As follow-up: Please see item Lc above..PDF preview welcome of items Lc/d/e prjor
to formal resubmittal of WPO plan since minor change to table C7 2, may address /clarify data.
(Rev. 2) Addressed.
f Include Exhibit or DA Map such that review can correlate VaRRM.xIs with DA A, B, C, D, and
with HydroCad routings. (Rev. 1) Addressed. Note: Engineering appreciates care in response to
this comment —thank you.
Engineering Review Comments
Page 3 of 8
2. CO. 1:
a. Revise plan title to include reference to W00202000039.
b. Note 4: Revise floodplain effective date to May 16, 2016, rather than Feb-4, 2005. [18-30.3.2,
https://library.municode.com/va/albemarle county/codes/code of ordinances?nodeId=CH18ZO ARTIIIDIR
E S30OVDI S30.3FLHAOVDIH. S30.3.2FLINRAMAFLINST]
3. C2.2: Calc. packet explains existing bioretention [south edge of site?] is removed with this project, but Ex.
SWM does not appear to be removed on this demolition sheet. Further, site outfall 2 is only accurate for a
13.77 Ac. area if Str. 202 outfall combines with bioretention facility 2B outfall, and it appears this does not
occur with proposed grading in proximity of bioretention 2B outfall, Str. 100. Please ensure facilities to be
removed are shown demolished, and that outfall 2 and corresponding calculations are accurate. See C5.0
image, below: (Rev. 1) Addressed. As ollow-try: Please revise W00202000039, C2.3 (near top center of
sheet where there is space with non -critical contours) to display image provided with comment response
letter (clipped from 8/22/1988 plan), with caption that references C2.2 Ex. concrete diversion structure.
Notes with caption that describe Ex. concrete diversion structure may be helpful, but are not required.
[Image removed with Rev. 2 comments.]
4. C4.0, C4.1: Label outfalls 1, 2, 3, consistent with Calc. packet.
5. C5.1: Label riprap outfall protection, L x W x D.
6. C5.4:
a. Label SWMI, and bioretention 2A, 2B.
b. Clarify pre-treatment (other than pretreatment cell) for bioretention facilities 2A, 2B. Ref. VA
DEQ Stormwater Design Specification No. 9, Table 9.3.
Underground or direct piped discharge to a Level 2 bioretention facility does not qualify as
bioretention pre-treatment. (Rev. 1) Partially addressed. As follow-yp: Please check Note titles,
C63 to see if edits needed. All ref bioretention filter 2A. (Rev. 2) Addressed.
BTWO FORMSOOF PRETREATME�B ED BjWO FORPISF LTERMN PROVIDED BTWOR FORMSOOrMETREA VIDED
BY GRAVEL FLOW SPREADER AND UPSTREAM BY GRAVEL FLOW SPREADER AND UPSTREAM BY GRAVEL FLOW SPREADER AND UPSTREAM
BY ISOLATOR ROW OF STORMTECH BY AN ACF TRASH GUARD CATCH BASIN BY A GRASS SWALE DIRECTING THE
DETENTION SYSTEM. FILTER. DRAINAGE AREA TO THE PRACTICE.
c. Label Emergency Access. Also label this access SWMAccess (bioretention 2A, 2B). [ No
proposed easement linework or easement plat is required, since parcel is county -owned.]
d. Confirm that bioretention facility 2B obtains building setback requirement, 25' downgradient from
building. (Rev. 1) Applicant response (12/2/20 letter) explains Bioretention 2B has been removed
from the plans.'
e. Flow splitter (Str. 126) and direction of flow in several pipes (circled) is unclear. Please add flow
direction arrows, and small-scale plan /profile detail for splitter structure 126. (Rev. 1) NA
Applicant: `Flow splitter structure has been removed from the plans as is no longer necessary with
the removal of bioretention 2B.'
i. C7.0 Str. 108-Str 126 notes that Str. 126 is M11-1 with splitter weir. Unless plan /profile
detail overlooked, please provide. (Rev. 1) NA Applicant: `Flow splitter has been
removed from the plan.'
ii. Ensure 6' MH has steps, that steps do not conflict with multiple pipe connections, or
weir. (Rev. 1) NA Applicant: `Weir is no longer proposed as flow splitter is removed
from plan. Steps will be installed per typical VDOT MH-1 details.'
iii. Revise C7.0 profile label (Str. 126) to read:
1. INV IN from Str. 128, else revise C5.4.
2. INV OUT to Str. 106, else revise C5.4.
3. INV OUT to Str. 110 else revise C5.4
4. INV OUT to Str. 122, else revise C5.4 (Rev. 1) Applicant: `Flow splitter has
been removed from the plan. All storm profiles have been updated to match the
current stormwater design.'
f Additional comments possible. [Image removed with Rev. 2 comments]
7. C5.5:
a. Label SWM2, and bioretention 2C, 3A.
Engineering Review Comments
Page 4 of 8
b. Clarify pre-treatment (other than pretreatment cell) for bioretention facilities 2C, 3A. Ref. VA
DEQ Stormwater Design Specification No. 9, Table 9.3. (Rev. 1) Partially addressed. Asfollow-
up: Please see item 6.b, above. (Rev. 2) Addressed.
c. Label geothermal well field (linework around IMP 56-64E label). (Rev. 1) Not addressed.
Although Applicant states: `Geothermal well field has been shown and labeled on Sheet C4.1,'
reviewer cannot locate label. Please direct reviewer to label, sheet # /point of reference, etc.
(Rev. 2) Addressed. Applicant response (letter d. 2/5/21): `Geothermal well has been relocated to
underneath the proposed bus loop. A label has been provided on Sheet C4.1. Please see clip
below.'
d. Provide bioretention 2C, 3A close -approach vehicular access. Current design forces use of bus
parking lot with no path for equipment or material to access either facility. A possible access
exists through curbing in bus circle, between circle and basketball court (though this may be
complicated by geothermal well field). Provide roll -type curbing and a traversable, stable SWM
facility access downslope to contour elevation 680'f. (Rev. 1) Not addressed. Applicant: `Close
vehicular access is provided by the bus loop for delivery of any materials and/or equipment.
Additional Access for maintenance activities is provided by the sidewalk adjacent to both
facilities. The typical maintenance for bioretention per VA DCR specification No. 9 is
maintaining the landscaping and mulch. Between the vehicular access of the bus loop and the
sidewalk path leading from the bus loop to these facilities access for maintenance is provided.'
This response conflicts with ACDSM requirements that apply to all SWM facilities. Response
considers typical as opposed to maintenance possibilities that require vehicular access: (Rev. 2)
Partially addressed. Applicant: `Per email correspondence and zoom call with John Anderson the
access to the bioretention areas has been worked out by providing mountable curb in the bus loop
area and reinforcing the adjacent sidewalk so vehicles may park on the sidewalk while accessing
the facilities.' As follow-un: Please revise C4.1 to show/label CG-6 to CG-7 transitions. At
transition/s, sidewalk gradually lowers, and is 2" lower over CG-7 section/s relative to CG-6
sections, to maintain gutter flow line. Provide begin/end transition points, notes, labels, to clarify
curb /walk /gutter design in areas proposed to have mountable curb. Provide C 1.1 CG-7 detail,
recommend provide transition (CG-6 to CG-7) detail. Also, on C4.1 ref. C 1.1 CG-7 detail.
1. All SWM facilities require vehicle access for equipment, machinery, and
material delivery during initial construction, and later.
2. ACDSM makes explicit ref. to SWM facility access, pg_12, ifnape, -:'_
[Image removed with Rev. 2 comments.]
3. At an elementary school, design should seek to avoid unintentional mixing of
school staff (especially students) and typically adult male personnel, third parry
vendors, etc. Applicant response assumes SWM maintenance personnel will
share the paths and walkways with children as young as age 5, that these
personnel, in discharge of duties that require transport of material or operation
of equipment, can do so safely without direct dedicated access to SWM
facilities. Revise: provide access required by ACDSM.
4. Please consider:
a. Inclement weather impact to walks, bus loop, pavement, etc., if SWM
facility maintenance personnel are required to access facilities via
walks, rather than via dedicated overland vehicle access.
b. Multi -party site visit: A number of personnel (contractor, county
[Water Resources, FES, ACPS], design team, DEQ, vendor, etc.) may
be on -site at the same time. Again, bus loop and walks are not
designed for this contingency.
c. Material /filter media: xx cy of filter media weighing tons,
wheelbarrow /hand transport from bus loop is impractical.
d. Mulch /plant deliveries. Same, impractical.
e. Equipment delivery, [ bobcat, backhoe, etc.]
Engineering Review Comments
Page 5 of 8
These items may not offload in the bus loop, or near children.
f. Stone delivery /placement. Same.
g. Specialized needs: video, vacuum, line flush, etc.
No item above may be typical, yet each is possible.
h. Limit interactions between Crozet Elementary community and SWM
maintenance personnel for obvious /less obvious safety -related reasons.
e. Label proposed (gradually -falling) looping asphalt path.
f. Reinforce a 12' long section of this asphalt path with material sufficient to support 6-ton vehicle
or track equipment that may need to cross to the infield to reach biofilter 2C. (Rev 1) Withdrawn.
Applicant: `It is not clear why a 6-ton vehicle is necessary to be able to access the specific location
identified. Per specification No 9 landscaping is the typical maintenance of bioretention facilities.
The only reason a 6-ton vehicle would need access to these facilities is for the delivery of mulch
which would be placed on site in a storage area to be spread in the facilities by a landscaping crew.
Vehicular access for offloading equipment and materials is provided by the bus loop and
additional access is provided by the sidewalk pathways adjacent to the bioretention facilities.
These pathways will be strengthened to support any small maintenance vehicles that require
access.' Context: Ford F-150 unloaded vehicle weight, 4,021 to 5,014 lb. (google search),
payload: 1,745 to 2,238. Total loaded wt.: up to 3.5 tons. Comment revised to recommendation to
permanently reinforce section/s of path sufficient to support 4-ton vehicle /track equipment that
may need to cross to the infield. Engineering is a division of county government. Perspective:
Whatever damage attends crossing/s of the track (light -duty asphalt section), however infrequent
crossings may be, will be home by ACPS. It seems reasonable to proactively minimize expense
or disputes that may arise between ACPS and vendors /contractor, even during initial construction,
that may reasonably be expected to occur. Comment withdrawn. Also, item 7.d, above.
g. Propose pre-treatment for bioretention 2C, show in plan view (also, 7.b., above).
8. C6.0: Provide inset plan view, 1" =10', for each of the six (6) SWM facilities. Label L x W (x DIA)
dimensions in each small-scale view of biofilter, or underground detention. Please consider As -built
requirements when providing SWM facility design features, dimensions, and details. (Rev. 1) Addressed.
Applicant: `With the plans already at 1"=20' the requested dimensions have been added to sheets C5.4 and
C5.5 without the need for 1 "=10' inset views. Manufacturers' details can and will be provided on the plan
for both detention systems for the final signature set submission. Requests have been made for preliminary
shop drawings from the manufacturers to help with the future as -built requirements.' Engineering accepts
this response.
9. C6.1: Provide label for debris cage to be installed to prevent obstruction of 4.32" slot weir (SWMI), and 4"
x 11.5" slot orifice.' Note: Precision to a hundredth of an inch may impose fabrication or post -construction
expense to either manufacture to this tolerance, or to perform routings, if As -built condition differs. Design
rarely specifies plate openings to this degree of precision, if tenth of a foot precision works nearly as well.
10. C6.2: Revise bioretention profiles:
a. Label top or bottom of hardwood bark mulch layer
b. Label media invert elevation
c. Label #8 stone invert elevation
d. Provide small-scale, scale -accurate cross sections that include:
i. Pretreatment
1. Cell
2. Labels
3. Critical elevations
e. Show additional pretreatment.
f Provide media mix specification (ref. DEQ Design Spec. No. 9, Table 9.3).
g. Ensure Max. ponding depth is 6 to 12 inches. Also, VA DEQ Design Spec No. 9, Table 9.3
footnote 2.
h. Show clearout graphically accurately, with 45-deg bends, not 90-deg T connection.
Engineering Review Comments
Page 6 of 8
i. Include plant details (Recommend L-series landscape plan sheet for bioretention SWM facilities):
i. Level 2 design requires plantings in addition to turf.
ii. If turf proposed, label /specify turf type.
iii. Provide plant schedule, to be drawn from list of Albemarle County native plants: provide
common or scientific name, qty, to aid review, inspection, and As -built review. (Rev. 1)
Partially addressed. As follow-up: Provide qty. (per species) to aid review, inspection,
and bond estimate. Also, Lt.1, please label SWM facilities consistent with other plan
sheets. (Rev. 2) Addressed.
j. Consider plan and profile elements and dimensions to be reported as As -built condition, deemed
necessary for proper detention or bioretention performance. Label, show, and provide items
needed to report As -built conditions. (Rev. 1) Addressed. Engineering appreciates BMP Practice
Documentation Note on C6.2.
11. C6.2 or C 1.2: (Rev. 2) Addressed.
a. Provide Nyloplast dome grate detail. (Rev. 1) Comment persists. Applicant: `A detail has been
provided on Sheet C 1. 3.' Please note: Sheet C 1.3 does not appear to be included with the plan set.
b. Provide Nyloplast Mfr-recommended installation notes, as needed. (Rev. 1) Persists. Please
include C1.3 in the WPO Plan set.
c. Provide Typ. details:
i. VDOT PB-1
ii. Nyloplast pipe bedding
iii. VDOT IS-1 (inlet shaping) (Rev. 1) Items above persist. Please restore C1.3.
d. 5.96 Ac. total disturbed area is inconsistent with SWPPP, Sec. 3, and C3.0 Project Description
(6.51 Ac). Please reconcile.
12. C6.4: Include attached file as text, on C6.4 (bioretention periodic inspection). (Rev. 1) Addressed. As
follow-up: Please ensure print on C6.4 is readable, at print scale. (Rev. 2) Addressed.
CZO:
13. Label SWM 1, SWM2.
14. Label underground detention system slope, if any.
C. 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 approved.
1. C3.0:
a. STI: Check bottom of stone weir elevation (possible error, since higher than crest of stone weir).
b. ST2: List bottom of trap elevation, likely 678.0'.
2. C3.1: Include paved wash rack detail (PCE); ref. ACDSM, p. 8 (link:
https://www.albemarle.org/Home/ShowDoeument?id=270 )
3. C3.2, C3.3: Although design tables include ST floor dimensions, label trap (L x W) dimensions in plan
view.
4. C3.3: ST3 bottom of trap elevation (680.5') is lower than bioretention 2C No. 57 stone invert elevation
(68 LOW). Please ref. VA DEQ Design Stormwater Specification No. 9, Sec. 6, 8. 1, Construction
Sequence, Construction Stage E&S Controls which requires notes and graphic details on the E&S plan
specifying that (1) the maximum excavation depth at the construction stage must be at least 1 foot above
the post -construction installation, and (2) the facility [sediment tran] must contain an underdrain.
5. C3.3, C3.4: Show and label STI, ST2, ST3 underdrains in plan view, each sediment trap. Show ST
underdrains running through embankments to daylight.
6. C3.3: Revise ST3 bottom of trap elevation, per VA DEQ Design Spec. No. 9 guidance.
7. C3.5:
a. Label ST3
Engineering Review Comments
Page 7 of 8
b. 2 sets of proposed contours at future SWM bioretention 3A, resolve contour conflicts.
c. Evaluate Swale /ditch velocity (Q2,r) to ST3 to ensure velocity in swale is non -erosive. (Rev. 1)
Addressed, Pg. 140 Calc. booklet indicates 2yr flow in swale < 0.82fps [ non -erosive], since Q2-y,
z0.82 ft3/s, and ditch x-section -1.75 112
8. C3.5, C3.7: Proposed grading shows —10' vertical interval across outdoor activity /loop trail area. While
ST3 is provided at N end of this area of disturbance, SF, or even SSE is inadequate ESC at S end of this
relatively large disturbed area. Moreover, the 100' stream buffer in several locations lies inside and
upslope of proposed super silt fence (SSE /wire -backed silt fence). This ESC design and level of stream
buffer protection is inadequate. Maximum length of graded slope draining to silt fence is 100'. Provide
additional measures, including diversion to additional trap/s. Additional review comments possible. (Rev.
1) Addressed. Applicant: `Super silt fence is provided upstream of the 100' stream buffer to the greatest
extent practical. Additional SSE has been provided to act as additional layers of protection upstream of the
100' stream buffer and to meet the requirements of VESCH Std. & Spec. 3.05. It should also be noted the
vast majority of this area is the existing playground which is a very flat area at an existing grade of less
than 2%. There are also large areas of the existing playground that will not be disturbed as they are
existing play areas to remain. Additionally, super silt fence has been added in two stages along the existing
swale between the playground and recreation field (outside of the limits now). One stage of super silt fence
would be sufficient per 3.05 as the maximum area to the swale is less than 1 acre and 1 CFS. The area
draining to the swale with STl in place is 0.49 acres at a C value of 0.36 which in a 10yr storm would still
only yield 0.88CFS. These additional areas of super silt fence should provide more than adequate
protection for the WPO area.' Engineering accepts response /design perspective.
9. C3.7, C3.9: Sheets indicate looping asphalt trail is constructed prior to completion of bioretention facility
2C. This trail is likely to incur significant damage during transition of ST3 to bioretention facility 2C.
Please ensure design allows construction of ST3/SWM facility 2C without damaging other improvements.
(Rev. 1) Addressed. Applicant: `Phasing has been revised throughout E&S sheets. Bioretention 2C and
3A are installed at the same time as the looping trail and playground work in Phase II. A note was added to
ensure stabilization of upstream drainage areas prior to installation of bioretention facilities. See Sheets
C3.4-0.5.'
10. C3.5, C3.7, C3.9: These sheets show grading and construction of SWM bioretention facility 3A. This
future SWM facility receives swale runoff from contractor staging and storage area. That area, in turn, will
transition to temporary classrooms, first, then a basketball court. These transitions involve land
disturbance, meaning the swale shown in ESC Plan, Phase II, III, IV appears to need to drain to a sediment
trap, that may transition to bioretention facility 3A once all contributing upslope drainage areas are
stabilized. Please consider sequencing and likely need for a fourth sediment trap to receive sediment -laden
runoff until contributing drainage areas are stabilized. SWM facilities may not be constructed until then.
(Rev. 1) Addressed. Applicant: `The E&S phasing has been updated to more accurately reflect the overall
phasing plans prepared by the architect. The contractor staging area will remain until almost the end of the
project with the basketball court as the final work to be done in the rear of the site after the staging area is
no longer necessary. Phase II and III have been updated to show the contractor staging area to remain in
phase II and be transitioned to the basketball court in phase III where the small amount of work can be
controlled by silt fence.'
11. C3.8:
a. Label Emergency Access.
b. Provide note that Emergency Access will be utilized once upslope areas stabilized to construct
bioretention facilities 2A, 213.
12. C3.9: If ST3 in ESC Plan Phase IV is actually, by this point, SWM bioretention facility 2C, include note
similar to note on C3.8 for permeable pavers, i.e.: `Install bioretention 2C once all uphill drainage area has
been stabilized.'
13. General: Coordinate SDP202000058 Major Site Plan Amendment Engineering review comments with
VSMP Plan revisions. (Rev. 1) Persists. Applicant: `Comments will be coordinated between submissions.'
(Rev. 2) Addressed. Applicant: `Major Site Plan Amendment and VSMP Plans have been coordinated.'
Engineering Review Comments
Page 8 of 8
D. Pollution Prevention Plan (PPP)— See Sec. A., SWPPP, above.
The PPP content requirements can be found in County Code section 17-404. This plan requires an Exhibit.
1. Include WPO202000039 on I I" x 17" Exhibit. (Rev. 1) Addressed.
Please send .PDF of revisions to plan reviewer prior to fmal print submittal. SWM Plan review item 7.d., above
Process;
After approval, 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 entails 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 (NA /$0 for this county project). The form identifies the contractor and responsible land disturber,
and the f e -o..,aining to be pair 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.
Forms can be found on the county's recently redesigned website (forms center) under Engineering Applications,
httos: //www. albemarle. ore/govemment/community-develol)ment/aonly-for/engineering-anal ications
httos: //www.albemarle. org/govemmenticommunity-developmentlrequest/pre-construction-meeting
WPO202000039 Crozet Elem Addition Renovation Site VSMP 030921 rev2 doe