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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: Old Trail Village, Blocks 15 & 12
Plan preparer: Roudabush, Gale & Assoc, Inc [914 Monticello Road, Charlottesville, VA
22902, cmulligan @roudabush.com]
Owner or rep.: March Mountain Properties LLC [1005 Heathercroft Circle, Suite 100]
Dave Brockman, dave@oldtrailvilla ee com
Plan received date: 15 May 2014, block 15
(Rev. 1, block 15) 15 Aug 2014
(15t submittal, block 12) 15 Aug 2014
Date of comments: 30 June 2014 (block 15)
(Rev. 1, block 15) 29 Sep 2014 (block 15, 12)
Reviewer: John Anderson
Note: Since blocks 12 & 15 are adjacent and could be developed simultaneously, comments affect both blocks.
Comments are presented under separate block headings. This is the initial VSMP review for block 12, second
VSMP/WPO plan review for block 15.
A. Stormwater Pollution Prevention Plan —block 15 (SWPPP)
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.
OLD TRAIL SUBDIVISION STORMWATER POLLUTION PREVENTION PLAN AND POLLUTION PREVENTION
PLAN, April 16, 2014 is commendable. The SWPPP/PPP covers 86.5 Ac. under General VPDES
Permit VAR100043, areas shown on sketch dated September 29, 2014. Bracket references VAR10,
July 1, 2014; htW: / /www.deq.vir inia. gov/ Portals/ 0/ DEO /Water/Publications /CGP2014.pdf . Please
revise SWPPP/PPP (P. # /17 -pg. SWPPP):
1. Number each page.
2. In addition to Concrete Wash -out Area [Part ILAA(e)(5)], Fueling Area [Part ILAA.(e)(2)],
Stockpile Area, and Porta -potty [Part ILAA(e)(7)] labels, furnish specific prevention design
information, including: secondary containment for fueling area; concrete washout area located
upstream of a sediment basin/trap; silt fenceiberm for portable sanitary facilities and solid
waste dumpster to prevent or limit stream or environmental impacts. Labels are insufficient
preventive design measures. [Details shared with ACCD during project meeting Sep -25
would be ideal.]
3. Show paved construction entrance with wash rack on SWPPP, block 15. [ACDSM, p. 27]
4. (P. 1) Revise Anticipated Project Completion Date to 5 -31 -2019, consistent with registration
statement.
5. Attach copy of VAR10 to SWPPP /PPP (link above): print /attach. [Part II.A.1.c.]
6. Revise SWPPP whenever development increases quantity of pollutants /stormwater [Part III,
J.l.b.]
7. SWPPP Availability — provide means of public review [Part II.D.3.]
8. (P. 2.) Runoff Coefficient /Site Map /Description of Existing Vegetation —ref. "SWM Plan," not
"Final Site Plan." Site plans are not approved as part of VSMP /SWM plans.
9. Site Area — Define site area consistent with sketch dated 9/29/14 (86.5Ac). [Part I1.1.4.]
10. Scott Bradshaw is identified as SWPPP contact: submit qualifications. List additional
personnel if any others qualified/expected to perform SWPPP inspections. [Part II.F.1.]
11. (P. 3) Item #3 — Revise "All points of construction ingress and egress shall be protected by a
temporary construction entrance" to reference paved construction entrance with wash rack.
Engineering Review Comments
Page 2 of 7
[ACDSM; also, #3, above]
12. (P. 4) Item #4 - Preconstruction meeting shall be held at county office building.
13. Item #4 -Name individuals who will be responsible for ensuring maintenance of installed
measures on a daily basis. ( #10, above) [Part II.A.6.]
14. Item #4 - Contact ACCD to schedule a preconstruction conference. ACCD schedules this
meeting.
15. Item #6 - Revise "Any necessary maintenance of the measures shall be accomplished
immediately upon notification by the County and shall..." -REF Part II.G.1 - notification by
County not prerequisite to corrective action.
16. Item #10 - "from traversing slopes or by installing mechanical..."
17. Item # 12 - Clarify: "...soil stockpiles at the locations shown on this plan or as directed by
engineer..." Design engineer /ACCD engineer? Stockpile area shown on SWPPP plan, block
15, sheet 1 /1, Aug -12, 2014, governs stockpile location.
18. (P. 5) Item #14 - Compare with ESC plan sequence of construction. ESC plan states storm
drainage facilities will be installed prior to rough grading, a problematic proposition.
19. Item #15 - Revise "which may be at final grade but will remain dormant (undisturbed) for
longer than 30 days" to read "for longer than 14 days" [Part II, A.2.c,(8)]
20. Item 417 -Edit. See VESCH listed temp seed mix, Piedmont, winter months.
21. Item #19 -For slopes stepper than 3:1, specify vegetative ground cover hardier than grass.
[ACDSM, 8.A.2.]
22. Item 421 - Clarify meaning. Statement is problematic, inconsistent with VESCH.
23. (P. 6) Item #22. - Clarify /confirm 3 percent grade.
24. Structural Practices: please also include: Paved Construction Entrance with Wash Rack;
Storm Drain Inlet Protection (VESCH 3.07); Mulching (3.35); Dewatering Device (3.26);
Slope Drains (3.15); Paved Ditches /Flume (3.16)
25. Stormwater Mana eg merit: Delete reference to "Final Site Plans "; reference "SWM plan."
26. Waste Materials: show waste dumpster location on SWPPP plan, block 15.
27. (P. 7) Maintenance and Inspection Procedures - Revise: 2" paragraph - identify personnel
[Part II.A.6. /7.]; 3rd paragraph periodically is non - specific [Part ILF.2.(a)/Part II.G.11; 3rd
paragraph - repairs within 7 days [Part II.E.1]; 4d' paragraph - "at least once every 10 days"
[Part II.F.2.(a)(2)].
28. (P. 8) Non - Stormwater discharges: Ref. Part ILAA.(e)(4) for control requirements. Delete
where possible.
29. (P.10) Hazardous products - Identify on -site location of MSDS sheets, a location accessible to
on -site contractors /inspectors.
30. Petroleum products, 2nd bullet - Specify measures intended to reduce potential for
contamination when refueling, changing vehicle fluids, etc [Part II.A.4.(e)(2)].
31. (P. 12) bullet -LIST tel. # for reporting spills /incidents [Part III.G.; Also Note, p. 16, VAR10]:
a. VDEQ, Valley Regional Office, M -F, 8:30 -4:30 - 540.574 -7800
b. VDEM, Nights, holidays, weekends - 1- 800 - 468 -8892
c. Local VSMP Authority: 434 - 296 -5832, M -F, 8 -5.
32. Revise Pollution Prevention Certification [Part II.A.8; Part III.K.1. /4.] exactly as follows:
Certification. Any person signing a document under Part III K 1 or 2 shall make the following
certification:
"I certify under penalty of law that I have read and understand this document and that this document
and all attachments were prepared in accordance with a system designed to assure that qualified
personnel properly gathered and evaluated the information submitted. Based on my inquiry of the
person or persons who manage the system, or those persons directly responsible for gathering the
information, the information submitted is, to the best of my knowledge and belief, true, accurate, and
complete. I am aware that there are significant penalties for submitting false information, including the
possibility of fine and imprisonment for knowing violations."
33. Sign/Date Certification.
34. (PP. 13, 15, 16) - Revise tables to allow more space for recording description of grading
activity (p. 13); description of the amendment (p. 15), description of BMP deficiency (p. 16).
Also, furnish tables or data sheets to accommodate inspection reporting needs listed at Part
H.F.4.(a) -(j).
Engineering Review Comments
Page 3 of 7
35. SWPPP Plan, block 15:
a. Label Court Mont Way.
b. Receiving Waters – revise "runoff from this entire area currently drains into Slabtown
Creek via an existing sediment basin," since not strictly accurate.
c. Receiving Waters – revise "As such, it will provide full containment for the denuded
areas," since not strictly accurate. Limited areas drain east to sediment traps.
d. Stormwater Management – revise "Approved plans (WP0201300021) shall function
as the SWM facility for this development," since WPO201300021 may not provide
full SWM control (see SWM, comment #3, below).
e. Compare Porta john locations: Potential Pollutant Sources, 2 °a paragraph, with
Installation and Maintenance, 7th paragraph – revise for consistency.
f. Include ESC legend. (see SWPPP plan, block 12, Aug -15, 2014)
g. [ For SWPPP plan, block 12, have design engineer sign plan ]
B. VSMP: SWPPP: Stormwater Management and Mitigation Plan –block 15 (WPO201400047)
– The stormwater management plan requirements can be found in County Code section 17 -403.
Plans reference a bioretention basin approved under WPO201200013 and refer to block 14 SWM Plan
submitted under separate cover (WP0201300021). WP0201300021 modified the approved bioretention
basin, enlarging it to accept runoff from drainage area defined on sheet 5 of this plan set, dated March 20,
2013. This approved SWM plan applies to the 19.25 Ac. DA (sheet 5). Sheet 5 of the current plan set
dated May 9, 2014 shows that runoff from portions of Fielding Run Drive and disturbed, graded areas do
not reach the modified bioretention basin. Please furnish SWM control that meets water quality and
quantity standards under Albemarle County Code, Ch. 17, WPO Ordinance for portion not routed to the
biorctcntion basin (modified sediment basin) under current design. (Rev. 1) Comment addressed; ref,
applicant response letter, 29 -Jul 2014. 3.91 Ac. of development runoff is assumed to route to the modified
sediment basin approved under WPO201300021 (future bioretention facility). 96.6% is routed, while 0.14
Ac. is not (0.11 and 0.03 DAs; Fielding Run Dr /Rowcross St). Design comments and request for design
information, #3 -8, below, however, take priority over examination of 0.14 Ac uncollected storm runoff.
2. Attach or transfer relevant sheets, elements and details of block 14 approved WPO (WP0201300021) to
current application to lend guidance and clarity during WPO review of block 15, during bonding,
inspection, and construction. WPO plans for block 15 may not be approved by simple reference to an
approved WPO without transferring relevant information. To reiterate, please include plan sheets listed
below for purposes of guidance and clarity (not analysis), since nearly all block 15 post - development
runoff routes to an approved modified (future) bioretention facility. (At present, and for some time, the
facility will serve as a sediment basin). Transfer sheets 4, 5, and 6 of approved WPO201300021 plan set
(Mar -20 2013) without change. Please label each sheet as a plan sheet taken from approved
WP0201300021. (Rev. 1) Comment partially addressed: as follow -up: please label each sheet as
originating with WP02013- 00021.
3. In addition, from sheet 2 of Mar -20, 2013 plan set, attach or transfer: sediment basin narrative, sediment
basin schematic elevations detail (including design elevations with emergency spillway), and plan view of
basin —label this information taken from approved WPO201300021. Further, please label major contours
(640', 650'). Confirm and label existing base of sediment basin elevation = 635.0' (Rev. 1) Comment
partially addressed. As follow -up to 10 -Sep discussion, please remove sheet 2 of WP0201300021. The
appearance of existing block 14 ESC measures may confuse. Instead, from WPO201300021 /sheet 2,
please include (with both block 15 and block 12 VSMP plans): Sediment Basin Narrative; Sequence of
Construction; Sediment Basin Schematic Elevations. These details link WPO201300021 modified
sediment basin design data to a future bioretention facility. Note /see New. #4, below: Bioretention has
Engineering Review Comments
Page 4 of 7
been approved for blocks 14 and 11, not the entire 19.25 Ac. area shown on sheet 5, WP0201300021.
While WPO201300021 provides perimeter ESC for block 12 and most of block 15, and provides SWM for
blocks 11 and 14, it does not provide future development (block 15 and 12) stormwater control beyond
46,286 sf of impervious area and 158,208 sf of lawn/cultivated turf area —ref. Short Version BMP
Computation spreadsheet detail shown on sheet 5, WP0201300021.
New:
WPO201400021 provides SWM control for 46,286 sf future development impervious area.
WPO201400021 schematic of blocks 11, 14, 12 & 15, as well as drainage area defined as 19.25 Ac, shows
future impervious area = 125,OOOsf (12 & 15). With revised WPO201400047, please compare 46,286 sf
impervious and 158,208 sf lawn (area) available under WPO201300021 with proposed block 15
development. If proposed impervious /lawn exceeds what is available under WPO201300021, provide
treatment. Note: Please see water quality narrative, bullet 3, sheet 5, WPO201300021: 8,700sf X 12in/ft —
104,400cu.in; 104,400 in3, under this methodology, provides WQ control for 'h" runoff for 208,800sf of
impervious area. Ave of 208,800 and 348,OOOsf = 278,400sf. Taking block 11 and 14 impervious areas
into consideration, 46,286sf is available —not 50,330sf listed in bullet 3. This calculation does not affect
block 11 or 14 approvals, but bioretention basin (treatment) volume available for future (block 15 and 12)
development is central to current reviews. We discussed this briefly 24- Sep -14.
5. Part II -B water quality criteria appear to apply to stormwater facility design of future development, to block
15 areas not covered by WPO201300021 (ref. 9VAC25- 870 -63). Please utilize VaRRM spreadsheet
design methodology for areas not covered under WPO201300021. Link: http:/ /Iis.virginia.gov /cg_i-
bin/legp604. exe? 000 +ree +9 VAC25 - 870 -63
6. In reporting post - development characteristics for use with VaRRM (or Short Version BMP), CN,
drainages, and land use /cover (including future blocks -17, 18) should be checked. Fielding Run Drive is
east boundary of block 15, and appears a divide, with areas just SW and to the east draining east. It appears
that proposed contours do not allow runoff from certain areas within the 19.25 Acreage on sheet 5
(WP0203100021) to reach the modified sediment basin/future bioretention facility. Underlying
suppositions bear review. It appears a portion of runoff from `current' (9.32 Ac) and `additional' (9.93 Ac)
areas depicted as reaching the modified facility does not. Figures used to show compliance for blocks 11
and 14 appear problematic or invalid, and require revision to show SWM compliance for blocks 15 and 12.
7. With revised WPO201400047, please furnish existing conditions with soil types/boundaries.
8. Furnish pre- /post - development drainage area maps.
9. Propose mitigation for stream buffer impacts (utility work; sheet 3) - § 17 -406
C. VSMP: SWPPP: Erosion Control Plan —block 15 (WPO201400047) — The erosion control plan content
requirements can be found in County Code section 17 -402.
Sheet 2, sheet 3 —turn off drainage structure layer (inlet and stormwater pipe layer). (Rev. 1) Comment
partially addressed. Proposal to install most of the storm system prior to grading introduces construction
feasibility concerns. Grading is pre- requisite wherever proposed pipe grade is higher than existing grade.
Please consider OSHA trench shoring requirements, VDOT storm sewer note (block 15 final site plan,
sheet 12), and logistical needs (block 15 road plan, storm sewer profile Ex. #32 427A). From a review
standpoint, proposed sequence is problematic.
Engineering Review Comments
Page 5 of 7
2. Sheet 2 - Restore baffle to existing modified sediment basin (ref. WPO201300021). (Rev. 1) Comment
void; baffle field verified 8- Sep -14.
3. Sheet 2 -Show IP and OP, temp construction culvert (ref WP0201300021, sheet 2A). (Rev. 1) Comment
withdrawn; review error.
Temporary diversion dikes (DD, labeled DV on sheets 3/5) are a perimeter control and should not be used
on constructed fill slopes (VESCH, p. III -53). Either relocate DD (with sediment traps) to toe of slope,
avoiding placement in stream buffer, or eliminate grading operations below diversion dikes (revise final
grades). Eliminate the circle inset details for grass lined channel (DV). These details with v- shaped
conveyance differ from VESCH typical detail for DD. Ref. Plate 3.09 -1. (Rev. 1) Comment withdrawn
- review error: temporary diversion dike (VESCH 3.09) is not selected. Diversion (VESCH 3.12) is control
ESC option shown on sheet 3 -see 29- Jul -14 comment response letter.
5. Sheet 5 -show non - erodible channel from the outfall of structure 63 at the south end of Fielding Run Drive
to sediment trap #1. Eliminate circle inset showing v- shaped grass lined channel section and select ESC
from VESCH. V -shape is prone to higher and erosive channelized flow. (Rev. 1) Comment addressed.
6. Show boundaries of sediment trap drainage areas, listed as 3.0 Ac. for each sediment trap (sheet 3). (Rev.
1) Comment addressed.
7. Show critical slopes, if any. (Rev. 1) Comment partially addressed. Clarify Critical Erosion Areas note,
which states critical erosion areas exist on this site (identify type /location of critical erosion areas). Also,
we recommend recurrent phrase "There are no critical areas onsite," be revised to state there are no seeps or
live watercourses -more precise descriptions that agree with Critical Erosion Areas note.
8. Remove floating SF labels, sheet 2. (Rev. 1) Comment addressed.
9. Show wash rack water supply for CE, sheet 2. (Rev. 1) Comment addressed
10. Indicate stockpile and staging areas. (Rev. 1) Comment addressed; see Adjacent Areas Note, ESC
Narrative, sheet 8.
11. Identify off -site borrow or fill sites. (Rev. l) Comment addressed; see Off -Site Areas Note, ESC
Narrative, sheet 8.
12. Existing contours south of Glen Valley Drive differ from both existing and proposed contours on Mar -20,
2013 Approved WPO for block 14. Please confirm that existing contours immediately south of Glen
Valley Drive and east of CE are accurate as shown. (Rev. 1) Comment addressed; contours confirmed
accurate.
13. Show orange SAF around modified sediment basin. (Rev. 1) Withdrawn; SAF at basin verified 8- Sep -14.
14. Show SAF along south side of Glen Valley Drive, to prevent trespass, sheets 2 and 4. (Rev. 1) Proximity
to residences on Glen Valley prompts request. Appreciate discussion with project representatives, 8-/10 -
Sep-14, relative to safety and welfare. No SAF requested along Old Trail Drive. (§17-102.A)
15. In areas shown to receive temporary seeding (sheets 4 and 5), include permanent seeding, mulch, and dust
control (PS, MU, DC). (Rev. 1) Comment partially addressed; letter, 29 -Jul, indicates misunderstanding
- request is for straw mulch (VESCH 3.35), with TS/PS (see Vegetative Practices, Note 4, Mulch (3.35),
80 # /1000sf, sheet 8).
New
Engineering Review Comments
Page 6 of 7
16. Calculate area impact to stream buffer for sanitary sewer line activity in stream buffer (sheet 4). (Rev. 1)
Comment addressed.
17. Confirm as -built modified sediment basin dimensions; compare with dimensions shown on approved
WP0201300021, sheet 2. Report any discrepancies between the two. (Rev. 1). Comment not addressed.
Much depends on modified sediment basin, approved to be converted to a bioretention facility designed to
treat 19.25 Ac., including block 15 and 12 runoff. Code basis for as -built data request for (future) SWM
facility —§ 17 -422. Although basin continues to serve as a sediment basin, WPO201300021 (block 14)
approved basin modification as preliminary step to conversion to SWM facility. Sheet 4, WPO201300021,
shows extent to which contours approved under WPO2012 -00013 change. Request for basin dimensions is
to confirm that modified basin matches design criteria, sheet 2, WPO201300021.
18. Please revise plan note that states: "All run -off is conveyed to the same original outfall location and outfalls
into Lickinghole Creek. Additional offsite and developed onsite runoff is being diverted through an
existing sediment basin for water quality treatment and detention" (bottom of 1St col., sh. 8). 0.14 Ac. of
block 15 runoff will not reach the modified sediment basin. The sediment basin is not recognized as
providing water quality treatment. A future bioretention facility is.
19. Label all drainage easements beyond public RW PRIVATE. Comment applies to blocks 12 and 15 — please
check labels carefully (existing /modified sediment basin, Rowcross St, Court Mont Way, Private alley `A'),
and please accept apology for error. This will be a standard item of review with future VSMP plans.
Easements beyond public RW are Private. (§ 18- 32.7.4.2.a.1.)
A. VSMP: SWPPP and Pollution Prevention Plan —block 12 (WP020140007l) — §17-405
(The Virginia stormwater management program, stormwater pollution prevention plan application and
documents
Refer to block 15, above: Comments virtually identical. Oct -2 meeting scheduled for questions.
B. VSMP: SWPPP: Stormwater Management Plan —block 12 (WPO201400071): Refer to block
15, above. WPO201400047 SWM comments (2.4.) apply to blocks 15 and 12, equally.
C. VSMP: SWPPP: Erosion Control Plan —block 12 (WPO201400071) —The erosion control plan content
requirements can be found in County Code section 17 -402.
1. Provide diversion dike or ditch, west side of modified sediment basin, sheet 3.
2. Revise CE to paved CE with wash rack, sheet 2.
3. Revise 668' contour to 666', lower right quadrant, sheet 2, near Future Development Area label.
4. Label all drainage easements beyond public RW PRIVATE. Comment applies to blocks 12 and 15 — please
check labels carefully (existing /modified sediment basin, Rowcross St, Court Mont Way, Private alley `A'),
and please accept apology for error. This will be a standard item of review with future VSMP plans.
Easements beyond public RW are Private. (§ 18- 32.7.4.2.a.1.)
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. No fee is required for VSMP re- submittals.
Engineering plan review staff are available from 2 -4 PM on Thursdays, should you require a meeting to discuss this
review. Plan review staff are also available at 434 - 296 -5832 ( -ext 3069) should you have questions.
Engineering Review Comments
Page 7 of 7
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/dgptforms.asp?department=cdengnMo
File: WP0201400047- WPO201400071 -OTV- blocks 15, 12- 092914