HomeMy WebLinkAboutWPO201600074 Review Comments WPO VSMP 2017-04-27COUNTY 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: Woodbrook Elementary School Addition
Project file number: WP0201600074
Plan preparer:
Timmons Group, Craig Kotarski. [craig.kotarski@timmons.com]
Owner or rep.:
Albemarle County School Board, Uletteri@kl2albemarle.org]
Plan received date:
Rev 1 — 30 Nov 2016
Rev 2 — 22 Feb 2017
Rev 3 —12 April 2017
Date of comments:
Rev 1 5 Jan 2017
Rev 2 — 23rd Mar 2017
Rev 3 — 25 April 2017
Reviewers:
Rev 1 — Bobby Jocz - VSMP
Geoff Elsie VESCP
Rev 2 — Bobby Jocz — VSMP/VESCP
Rev 3 — Bobby Jocz — VSMP/VESCP
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 Approved
pending identified changes. The rationale is given in the comments below. The application may
be resubmitted for approval if all of the items below are satisfactorily addressed. 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. Provide signatures for the registration statement.
Rev 2 — Addressed
2. Provide signatures for the Certification Statement (section 9).
Rev 2 — Acknowledged
3. Complete/sign the Delegation of Authority (section 10).
Rev 2 — Acknowledged
4. Provide a copy of DEQ coverage letter when obtained.
Rev 2 — Acknowledged
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17-404.
1. Provide proposed locations for concrete washout, material delivery and storage, and portable
sanitary facilities as noted in PPP on the plans.
Engineering Review Comments
Page 2 of 6
Rev 2 — Addressed
2. Revise plans for diverting wash waters to sediment basin. No diversion dike is shown adjacent to
the construction entrance as stated.
Rev 2 — Addressed
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a
SWMP. This plan is Approved pending identified changes, 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. Remove Sheets C1.1, C1.2, L1.0, L2.0. L3.0, U.1, L3.2, C4.0. Not needed for Erosion and
Sediment Control or Stormwater Management review or installation.
Rev 2 — Partially addressed, Remove sheet C7.0 and correct mislabeling of sheet C8.1. It is
currently labeled as "Stormsewer Drainage Areas". Sheet 8.1 as labeled is missing, including
the profiles for drainage structures SWM B — 204, 200 — 204, SWM B — 213, and 211— 204.
Please correct
Rev 3 — Sheet 6.0 showing auxiliary site improvements is now no longer included in the
plans. Please replace.
2. Re -name cover sheet to identify the submission as a VSMP plan, make sure to include the WPO
submission number (WPO201600074).
Rev 2 — Addressed
3. Original Signature of professional engineer will be needed for final submittal on both the plan
sheets and supporting design calculations.
Rev 2 — Acknowledged
4. Remove section of demolished pipe shown extending from SWM facility A to the roadway from
the Auxiliary Site Improvements sheet [C6.0]. Verify all sheets are expressing intended
information.
Rev 2 — Addressed
5. As stated in site plan comments, provide details for proposed storm sewer structures (i.e.
Doghouse MH, surface drains, DI-1, DI-3C, MH-1, etc). All structures must meet VDOT
standards. Provide details for SWM facilities including, inspection and maintenance
access/schedules/procedures, pipe inverts, profile views, cross sections, backfill materials and any
other details necessary to properly identify and evaluate SWM facility designs.
Rev 2 - Not addressed, SWM facility details and long term maintenance details must be
provided as stated above. Details still not provided for Doghouse MH, and DI-1 structures.
Rev 3 — Addressed
6. Provide manufacturer specifications proving pollutant removal efficiencies specified in VRRM
spreadsheet.
Rev 2 — Addressed
7. Revise storm sewer profile labels to match the structures being represented in the profile. For
instance, the profile showing STR 138-SWM A is labeled as STR 100-106, which is not what is
represented in the profile. Please correct.
Rev 2 — Addressed, however some profiles are missing, including the profiles for drainage
structures SWM B — 204, 200 — 204, SWM B — 213, and 211 — 204. Provide all existing and
proposed stormsewer in profiles. This includes Ex 16 —148. Please correct.
Rev 3 — Addressed
8. Provide proposed grading on profile for SWM A - STR 100 [sheet C8.0] or indicate no change.
Rev 2 — Addressed
Engineering Review Comments
Page 3 of 6
9. Profile scale does not match vertical scale presented in profiles [Sheet C8.0, C8.1]. Please correct.
Rev 2 — Addressed
10. The labeling of proposed drainage areas (A and B) in Runoff Reduction Spreadsheet, design
calculations, and drainage area maps is inconsistent and needs to be corrected. The labels appear to
be swapped in the Runoff Reduction Calculations.
Rev 2 — Addressed
11. In the Water Quality Analysis section on sheet C 10.0, the value provided for Q(10) Pre -developed
differs from the one shown calculated for the 10 year pre developed condition in the model. In
addition, the elements labeled in RV (1 Year Post) under "Drainage Area A" are mislabeled as
Post Developed B detained and Post Developed B Un-detained. Please verify and correct this.
Rev 2 — Partially Addressed. The water quantity section corrected; however, Water quality
analysis figures on sheet C10.0 now do not match those represented in the VRRM
spreadsheet for; disturbed acreage, pre/post-developed conditions, and total load reduction.
Please Correct.
Rev 3 — Partially addressed. Values used for calculating drainage area B Rv(1YR POST) are
inconsistent between the calculations booklet and the plan sheets. The calculations booklet
places the 1 year post development Rv at 0.19 of (detained) and 0.079 of (un-detained) or
8,276 CF(detained)+ 3,441 CF(un-detained)=11717 CF, whereas the plan sheets states this
as 3,613 (detained) + 7,884 CF(un-detained)=11396 CF. This brings the required post
development Max Q(1) from 2.24 CFS to 2.19 CFS which is equal to the calculated post
development Q(1) for drainage area B. Please clarify and/or correct.
12. Verify throat lengths for inlets are correctly identified and modeled on the LD204 form. Structures
are shown to have throat lengths of 2' which contradicts throat lengths identified for those same
structures elsewhere in the plans.
Rev 2 - Addressed
13. Verify calculations for STR 122 and STR 106 are correct. Carryover is shown through STR 122,
but is not modeled entering STR 106.
Rev 2 - Addressed
Additional Review 2 Comments:
14. Inlet 122, as referenced in the LD204 spreadsheet and storm drainage area map, does not
exist as an inlet identified on stormsewer system in plan views or drainage profiles. Please
correct or clarify.
Rev 3 - Addressed
15. Some of the drainage areas in sheet C8.1 indicate drainage to inlets that do not exist as part
of identified stormsewer system in plan views or drainage profiles. For example, the roof of
the gym and stage/dining areas are indicated to be draining to structures 123 and 121
respectively on sheet C8.1, but those structures are not identified anywhere else in plans or
calculations. Please correct or clarify.
Rev 3 — Addressed
16. Water quality analysis figures on sheet C10.0 do not match those represented in the VRRM
spreadsheet for; disturbed acreage, pre/post-developed conditions, and total load reduction
required. Please correct.
Rev 3 — The Area B Summary BMP selection chart contains values inconsistent with that
presented in the VRRM spreadsheet, and in calculations booklet. Please correct.
17. Structure 108 exceeds maximum spread conditions. Inlets in sump conditions must
rnnintnim cnrParlc less than 10'.
Rev 3 — Addressed
18. �iuructurc r.x. ii. is modeled to not intercept any flow, as a result a large amount of
Engineering Review Comments
Page 4 of 6
carryover is shown leading to concerns about flooding. Please correct or clarify.
Rev 3 — Addressed
D. 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, and the reasons are provided in the comments below. The erosion control
plan content requirements can be found in County Code section 17-402.
Remove Sheets C1.1, CL2, LLO, L2.0. L3.0, U.1, L3.2, C4.0. Not needed for Erosion and
Sediment Control or Stormwater Management review or installation.
Rev 2 — Partially addressed, Remove sheet C7.0 and correct mislabeling of sheet C8.1. It is
currently labeled as "Stormsewer Drainage Areas". Sheet 8.1 as labeled is missing, including
the profiles for drainage structures SWM B — 204, 200 — 204, SWM B — 213, and 211 — 204.
Please correct
Rev 3 — Addressed
2. Correct title block for Sediment Basin Design, Sheet C3.0, currently refers to Permanent Seeding
for the Piedmont.
3. Rev 2 — Addressed
4. Sediment Basin detail elevations do not match those provided on plan sheet C3.1 and C3.2 (for:
top of dam elevation, barrel out invert, bottom of basin, principle spillway crest, etc.). In addition,
basin volumes provided in the detail do not match those provided in the component breakdown
spreadsheet. Please correct and provide updated calculations if necessary. Ensure basin design is
compliant with VESCP standards. Also note: Baffles required if L/We is < 2, not greater than 2 as
stated in detail spreadsheet.
Rev 2 — Addressed, replaced basin with sediment trap
5. Show stockpile areas and associated controls.
Rev 2 — Addressed
6. Verify location of Construction Entrance. It should be located at the entrance to the construction
site with wash facility or barricade. Current location appears to be too far inside site.
Rev 2 — Addressed, second CE added
7. Add Safety Fence with signage that reads Danger Quicksand around Sediment Basin.
Rev 2 — Addressed, basin replaced with trap
8. Show detail for tree protection, temporary slope drain, and culvert inlet protection as specified to
be installed in the structural practices and sequence of installation notes presented on sheet C3.0.
Also specify where these practices will take place on site. If these practices are not to be used,
remove them from the narrative.
Rev 2 — Addressed
9. Show Permanent Seeding and Mulching at the CMP pipe from the Basin to the doghouse. Sheets
C3.1 and Sheet C3.2 insert.
Rev 2 — Addressed
10. E&S measures and limits of clearing and grading must extend to the portion of stormsewer
installed from the north portion of the site to Brookemere Drive for Phase II E&S (Sheet C3.4).
Rev 2 — Addressed
11. Extend silt fencing across the southern portion of the site along Idlewood Drive.
Rev 2 — Addressed
Additional Review 2 Comments:
12. Correct deficiencies in E&S narrative:
Engineering Review Comments
Page 5 of 6
a. Incorrect project area identified in description.
Rev 3 — Addressed
b. Stormwater runoff considerations state that nutrient credits will be purchased,
however quality will be treated using Bayfilters according to SWM plan.
Rev 3 — Addressed
c. Structural practices still include sediment basin description and maintenance
practices. Please correct to sediment trap as specified.
Rev 3 — Addressed
d. Phase II sequence of construction still includes the conversion of sediment basin to
underground facility. Please update to reference current E&S plan measures.
Rev 3 — Addressed
13. Provide detail for paved construction entrance per County Design and Standards Manual
Ch. 3.
Rev 3 — Addressed
14. Please confirm drainage area to sediment trap. GIS appears to show the provided trap's
drainage area to be larger than 3 ac. Sediment traps are not to be used for drainage areas
larger then 3ac.
Rev 3 — Addressed
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, 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 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
Engineering Review Comments
Page 6 of 6
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;
hqp://www.albemarle.org/deptforyns.asp?department--cdengno
Bobby Jocz, EIT
Civil Engineer 1
(434) 296-5832 ext: 3283
County of Albemarle
Department of Community Development
401 McIntire Rd.
Charlottesville, VA 22902