HomeMy WebLinkAboutWPO201900068 Review Comments WPO VSMP 2019-12-13COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
VSMP Permit Plan Review
Project title: Red Hill Elementary School — VSMP
Project file number: WP02019-00068
Plan preparer: Jonathan Showalter, Timmons Groupfionathan.showalter(&timmons.com]
608 Preston Ave., Suite 200 / Charlottesville, VA 22903
Owner or rep.: Albemarle County School Board (Joe Letteri)
Plan received date: 26 Nov 2019 — Digital
Date of comments: 13 Dec 2019
Reviewer: John Anderson
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 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. This SWPPP is disapproved,
and the reasons are provided in the comments below.
1. Section 1, Registration Statement /Sec. V.C.: Check `No,' unless land disturbance has commenced.
2. Section 1, Registration Statement /Pg. 4: Sign /Date.
3. Section 6.A. /Exhibit (p. 21-22, .PDF): Indicate initial location of rain gauge.
4. Section 6.A. /Exhibit (p. 21-22, .PDF): Revise LOD: SWPPP Exhibit + SWM /ESC inserts + VSMP /WPO
Plan. 0.94 Ac. as shown is unrealistic, and includes isolated areas without connection to CE, or material
storage /laydown (unless access is through Ex. building). Assume areas crossed with equipment during
construction are disturbed by virtue of compaction or end -of -project typical need to till /amend soil, clear
debris, restore, or install temporary /permanent stabilization. Ref. isolated areas of proposed LOD, image,
below. Again, disturbance will likely exceed proposed limits as a practical matter. Engineering questions
need for limiting LOD < 1 Ac. There is no appreciable delay when applying for a DEQ VPDES VAR10
permit, and no additional requirements since LOD >10,000 SF in Albemarle triggers VSMP requirements
identical with requirements that apply to projects with LOD > 1 Ac.
1 i
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Engineering Review Comments
Page 2 of 6
5. Section 6.A. /Exhibit (p. 21-22, .PDF): Indicate initial location of temporary solvent /chemical storage
(temporary material storage trailer).
6. Section 7, Impaired Waters: Revise proposed enhanced inspection frequency (item (2)) consistent with
VAR10, Part II G 2. a. (2.) (Ref. pg. 13 /VAR10).
7. Section 7: Furnish missing (TMDL /impaired) data for North Fork Hardware River, since designated for
enhanced inspection.
8. Section 9, Signed Certification: Sign — date.
9. Section 12: Revise proposed enhanced inspection frequency (item (2)). Also, item 6., above.
10. Sec. 1, Registration Statement, p.2, Sec. IV, E —MS4: Leave blank since project does not discharge to
Albemarle County MS4. See County GIS /Map Themes (Layer) /Utilities [Water-Wastewater-Stormwater
/Albemarle County MS4 boundary. Red Hill is well outside /south of Albemarle County MS4 boundary.
11. Revise SWPPP title to include reference to WP0201900068.
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 reasons listed, below. The stormwater management plan content requirements can
be found in County Code section 17-403.
1. Revise title to: Red Hill Elementary School Additions and Renovations VMSP WP0201900068.
Please QC: do not submit plan titled Site Plan, or Site Plan Amendment as a VSMP /WPO Plan.
2. C2.0: Revise to show TMP 08700-00-00-060BO (Thomas Brendt) since design proposes to release
runoff to a LS, then a slope leading to this property, rather than a defined channel. Show residence
at 3947 Red Hill School Road. Show property boundaries consistent with GIS. Label TMP #
08700-00-00-060130. (County GIS, image, below)
3. C6.0: Water quality calculations /surplus removal: Plan proposes to utilize 0.44 lb. surplus phosphorus from
Scottsville Elementary School Addition project (0.44 lb. of 0.44 lb. total); plan also proposes to use 0.06 of
0.15 lb. surplus phosphorus from Woodbrook Elementary School project to meet Red Hill projects 0.50 lb.
TP Load Reduction requirement. This works only if Woodbrook and Scottsville Elementary are located in
the same HUC or upstream HUC (see, below), and Woodbrook and Scottsville schools are not in the same
HUC or upstream HUC. Revise WQ compliance plan. (Ref. images /link, below. Also: Scottsville —
WP0201900051; Woodbrook — WP0201600074):
9VAC25-870-69A. /Offsite Compliance Options (5.): `5. When an operator has additional properties
available within the same HUC or upstream HUC that the land -disturbing activity directly
discharges to or within the same watershed as determined by the VSMP authority, offsite
stormwater management facilities on those properties may be utilized to meet the required
phosphorus nutrient reductions from the land -disturbing activity.'
9VAC25-870-10 /Definitions: "'Hydrologic Unit Code" or "HUC" means a watershed unit established
in the most recent version of Virginia's 6th Order National Watershed Boundary Dataset unless
specifically identified as another order.'
Engineering Review Comments
Page 3 of 6
Link NA 61 order HUC Map:
httos://www.dea.virizinia. izov/Portals/O/DEO/Water/WaterOualitvAssessments/InteeratedReoort/2016/maDsNA
NWBD v4.pdf --- Red Hill Elementary, HUC JM46
RfrO NICE SONOOL RD
Hydrologic Units Identified
B digit 10 digit 12 digit
Total features returned: 1
HUC12 VAHU6 0
020HU20312U1 }M46 tgorth Fork Hardware
how Rive
I
714 fl
Scottsville Elementary, HUC JM44
Hydrologic Units Identified
B digit 10 digit 12 digit
Total features returned: 1
HUC12 7VAHU6 NaOme
020802031103 (show) ]M44 otie, Creek
From VA 6' order HUC Map (JM46, JM44, JR08); Image Above
RpO WLL SCHOOL F
�JR06
1 l R04� Mil JR
.:IR03 JROS �dRR773
JR02 -!�
Engineering Review Comments
Page 4 of 6
Woodbrook Elementary, HUC JR08
'1
Hydrologic Units Identified
B digit 10 digit 12 digit
NVC12 VAH Vb;i rums i
02090204020i gR08 5-th Ferk Riv —
h River /J)
f
SIN
0R
C5.0:
4. Post -developed runoff may not release to undefined channel so close to a neighboring residential property.
Revise design.
5. Str. 100 /outfall: Evaluate effect of existing impervious runoff on existing channel along Red Hill School
Road. Evaluate 10-year event, whether Ex. roadside ditch has adequate capacity, and whether ditch flow
bypasses driveway entrance to 3947 Red Hill School Road to reach tributary to South Branch.
—Al
-
TM-SE-1
6. LS in this location is problematic. Ref. 9VAC25-870-66.D., which cautions against downslope effects.
Also, item 4., above. LS releases to featureless slope toward 3947 Red Hill School Road (Brendt property).
-LEVEL SPREADER. 26' WIDTH. AERT9L11yE=-r
_ - DOWNSTREAM GRADE FLUSH
WITH TOP OF WALL
" TOP OF WALL ELEV = 713.59' 202
.J
i SEE DETAIL ON SHEET C6 D J 201
I 1 :RAP T STD. CLASS Al
RIP CHANNEL
WITH t%SLOPE r
FROM PIPE
Engineering Review Comments
Page 5 of 6
9VAC25-870-66.D.
D. Increased volumes of sheet flow resulting from pervious or disconnected impervious areas, or from physical
spreading of concentrated flow through level spreaders, must be identified and evaluated for potential impacts
on down -gradient properties or resources. Increased volumes of sheet flow that will cause or contribute to
erosion, sedimentation, or flooding of down gradient properties or resources shall be diverted to a stormwater
management facility or a stormwater conveyance system that conveys the runoff without causing down -
gradient erosion, sedimentation, or flooding. If all runoff from the site is sheet flow and the conditions of this
subsection are met, no further water quantity controls are required.
7. C5.2, C6.0: Consider effect of relocated (impervious) modular trailers on post -developed ground cover.
Analyze trailer DA (C5.2). Show trailer leader line outfalls. Adjust post -redeveloped ground cover (C6.0).
8. C7.0: Provide Std. VDOT MH with STR206-STR200 profile. Nyloplast® does not meet Drainage Plan
checklist, ACDSM, or VDOT drainage manual guidance. Nyloplast is appropriate only for yard grates, or
limited conveyance over limited distance. Use Std. VDOT MH Str. with 12" RCP storm pipe.
9. C7.0: Str 218 — 214: Revise 4" storm line to 6" Min.
10. Remove sheet E0.4, Site Plan Photometrics.
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 disapproved for reasons listed, below. The erosion control plan content requirements can be found in
County Code section 17-402.
2.
3.
C3.2:
C3.1: Include ACDSM paved construction entrance detail.
C3.2, C3.3: Revise LOD. Also, SWPPP comment, item 4., above
C3.3, C3.4: Label mulched areas, trails, etc. (blue arrows, below). Confirm whether trails or play areas are
to be constructed on existing grade, with no disturbance, whatsoever (i.e. outside LOD). Label circular
features shown below.
ttK4 Lw
N
V" c
Engineering Review Comments
Page 6 of 6
4. Label ST floor dimensions.
5. Provide break in SF at ST stone weir (outfall).
6. Revise CE label to PCE (paved construction entrance).
7. Revise ST L:W ratio to more nearly resemble (VESCH Std. & Spec. 3.13) 2:1 length -width ratio.
8. C3.3: Provide labels to identify five circular areas material surface type. Show proposed grading for level
circular areas, if areas are to be level. If grading is required, revise LOD /VaRRM.xls. Also, see SWPPP
item 4., ESCP item 3., above.
9. C3.2, C3.3: Show PS, MU for five circular area, within areas of land disturbance, or grading.
10. C5: Show grading required to level pads for relocated modular trailers, an activity included with this project
(Note Ex. contours: 723, 722, 721). Revise LOD.
11. C6.0 Riprap channel detail: It is unclear whether this detail defines C3.3 ESC feature, or permanent feature.
Please clarify.
D. Pollution Prevention Plan (PPP) — Ref. SWPPP, Sec. A, items 3, 4, 5, above.
The PPP content requirements can be found in County Code section 17-404. This plan is disapproved
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, if LOD > 1 Ac., 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. The form identifies the contractor and
responsible land disturber, and the fee remaining to be paid (NA, for Red Hill Elementary, a county project). 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;
htW://www.albemarle.org/deptforms.asp?department--cdengmTo
WPO201900068 Red Hill Elementary VSMP 121319