HomeMy WebLinkAboutWPO202100070 Correspondence 2022-01-27RKI%K
2100 East Cary Street
Suite 309
Richmond, VA 23223
Phone 804.782.1903
Fax 804.782.2142
www.rkk.com
Date: January 21, 2022
To: John Anderson, PE
From: Amy Samberg, PE (RK&K)
Cc: Malachi Mills, PE (RK&K)
RE: Worrell Dr. — Road Plan
SUB-2021-00115, WPO Review#1
WPO Comments (dated 12/22/2021)
MEMORANDUM
A. Stormwater Pollution Plan (SWPPP):
1. Please ensure SWPPP cover includes reference to WPO2021-00070.
• Response: SWPPP cover includes reference.
2. Submit SWPPP using county template located at:
https://www.a I bema rle.org/home/showpu bl isheddocu me nt/166/637202310327530000
a. Sec. 1: Registration Statement; please complete. Feel free to call if any questions.
b. Sec. 6.A.: PPP Exhibit: Please show initial location of:
i. Rain gauge.
ii. Portable sanitary facilities (porta-john), as required.
iii. Covered non -hazardous waste dumpster, if required.
iv. Vehicle wash waters, draining to trapping measure (Not a sediment trap design,
per se, but shallow depression —1-2 backhoe buckets. Avoid direct drainage to
Ex. storm system, or pond/s.)
V. Concrete wash -out.
vi. On -site fuel, if required.
vii. Paint, stucco, chemical storage, if required.
c. Sec. 6E: List named individual responsible for PPP measures.
d. Sec. 8: Although County personnel will inspect, Applicant is required to retain qualified
(contractor/third-parry) E&S inspection personnel to perform ESC inspections and
evaluate compliance relative to VESCH, 3rd Edition, 1992.
e. Sec. 9: Ensure Signed Certification is signed and dated.
• Response: SWPPP has been added and sheets/items have been included as requested.
B. Pollution Prevention Plan (PPP): —see SWPPP item 2.b., above
1. The PPP content requirements can be found in County Code section 17-404.
0 Response: Pollution Prevention Plan (PPP) sheet C3.00A has been added.
C. Stormwater Management Plan:
1. Please revise plan set title to: Worrell Drive Improvements VSMP /WPO2021-00070
• Response: Plan Set title has been revised in sheet C0.00.
2. Sheets C8.0, C8.01, C12.00, C12.01, C12.02, C13.00, included with the ROAD plan, should be
removed from the VSMP/WPO plan.
• Response: Sheets are removed from the set for this submission.
3. Sheet 28 of 35-sheet plan set, titled Topeka's Steakhouse (sheet 10 of 10), appears intended as
an exhibit but Worrell Drive lies at elevation higher than drainage areas X, Y, Z; it is not
immediately clear that this past design is relevant to Worrell Drive Improvements. Please place
sheet 10 exhibit in context of Worrell Drive Improvements.
• Response: Site stormwater compliance notes on sheet C11.02 have been updated to
provide exhibit in context of Worrell Drive Improvements.
4. Please revise C11.04, C11.05 HydroCad subcatchment labels to correspond with Pond 1, 2, 3, 4
drainage areas, or easily -identifiable identifiers from C11.01 so routings may be more -easily
interpreted in context of DAs. Additional comments possible. Note: A HydroCad
schematic/flow diagram with subcatchment areas should be included as index to guide review.
• Response: Identifiers have been added as requested and HydroCAD report has been
updated on sheets C11.04 and C11.05.
5. It is unclear if this VSMP /WPO plan proposes to rely on 9VAC25-870-47 or 9VAC25-870-48
(Criteria IIB; prior -approved plan; existing VAR10). Provide stormwater quality and quantity
narrative/s explaining: design, criteria, compliance regime (IIB or IIC design criteria, as
applicable). Provide VaRRIVI.xls, as needed. Provide channel /flood protection calculations.
Additional comments are possible.
• Response: Site stormwater compliance notes on sheet C11.02 have been updated to
provide clarification on requested information.
6. C9.00, Storm sewer 5-1 to 5-2: Provide a high -flow bypass design for level spreader (LS) in fill
section. If bypass channel is located in earth fill, armor bypass against erosion. Provide channel
lining design for LS high -flow bypass (stone (below L5), EC-2, EC-3).
• Response: Storm sewer design 5-1 to 5-2 has been revised and level spreader has been
removed. Storm sewer run has been extended closer to existing pond.
7. Note: An Approved WPO plan is required prior to receiving a Grading Permit.
• Response: Acknowledged.
D. Erosion and Sediment Control Plan (ESOP):
1. C4 series
f. Provide ESC legend.
g. Label Area of disturbance (LOD = x.xx Ac.).
h. Provide SAF, as needed, to protect pedestrians using Ex. path/s from construction
activities, and to discourage trespass.
• Response: Requested items have been added to E&S plan sheets (C4.XX series) and MOT
plans for coordination on different construction phases.
2. C500: Provide note discussing disposition of export /demo material: 'Waste asphalt to landfill;
for example.
• Response: Note has been added to sheets C5.00-05.02.
3. C600: Label reading 'Maintain access to Martha Jefferson Dr and Worrell Drive at all times'
appears at odds with MOT, which appears to indicate episodic, brief closure of Worrell Drive.
• Response: Label has been removed to avoid inconsistencies with MOT plans.
4. C7.00, C7.01:
a. Provide L x W dimensions for outfall riprap. At Str. 3-1, 4-1, 5-1 dimensions appear to
reference LS design. If this is the case, provide LS section/s to help correlate dimension
labels (C7 series) with LS design. Several pipe outfalls without level spreaders have Vol.
(cy) labels, which are helpful, but L x W x D (EC-1 Type 1A) labels will aid plan review,
bond estimate, installation, and inspection.
• Response: Requested dimensions are added to outfalls.
b. Provide grade contours at 2-2 (or spotshot) to ensure positive drainage to grate.
• Response: Spot shot has been added to Rim elevation of structure 2-2.
c. Provide pond 2 WSEL and structure 6-1 INV out label on this plan sheet.
• Response: Pond 2 WSEL and Inv out Label on structure 6-1 has been added to sheet
C7.01.
d. Provide level spreader detail consistent with VA DEQStormwater Design Specification
No. 2 (https://www.swbmp.vwrrc.vt.edu/wp-content/uploads/2017/11/BMP-Spec-No-
2 SHEET -FLOW v1-9 03012011.pdf)
• Response: Detail has been added to sheet C7.01.