HomeMy WebLinkAboutWPO201900050 Review Comments WPO VSMP 2019-11-25 (2)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 title:
Project file number:
Plan preparer:
Owner or rep.:
Plan date:
Plan received date (County)
Plan received date (WWA):
(Rev. 1)
(Rev. 2)
(Rev. 3)
Date of comments:
(Rev. 1)
(Rev. 2)
(Rev. 3)
Reviewer:
VSMP Permit Plan Review
Berkmar Overlook VSMP
WP02019-00050
Collins Engineering
Berkmar Development, LLC
August 29, 2019
September 9, 2019
September 16, 2019
7 Oct 2019
19 Nov 2019
22 Nov 2019; email /not digital plan [11/22/2019 7:42 PM]
September 25, 2019
13 Nov 2019
22 Nov 2019
25 Nov 2019 -email / Laserfiche [11/25/2019 4:01 PM]
WW Associates, Inc. (Rev. 1,23 /J. 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.
1. Provide a SWPPP, using the Albemarle County template. (Rev. 1) Partially addressed. Asefollow-up,
please see items, below. [ Once revised /complete, .PDF preview of SWPPP only is welcome. Given
current Division workload, print resubmittal of WPO Plan is needed.] (Rev. 2) Addressed.
2. 17-403.A.2: Provide a telephone number and contact email address for the owner. (Rev. 1) Not addressed.
Please submit 2019 VPDES Permit Registration Statement (please ensure complete, signed, etc.). Link:
hqp://www.albemarle.orWupload/images/forms center/departments/Community_ Development/forms/Engineering and
_WPO Forms/CGP Registration Statement 2019 FINAL 201904.pdf (Rev. 2) Addressed.
3. 17-403.C: Provide signature on Engineer's seal. (Rev. 1) Not addressed. (Rev. 2) Addressed.
4. Provide a signed certification in accordance with 9VAC25-870-370. (Rev. 1) Not addressed. (Rev. 2)
Addressed.
5. Provide a Delegation of Authority. (Rev. 1) Withdrawn. A blank Delegation form is enclosed; which is
sufficient.
6. Provide a copy of the General Permit with the final SWPPP. (Rev. 1) Not addressed. Link to 26-pp. 2019
VAR10 VPDES permit:
http://www.albemarle.org/upload/ima2es/forms center/departments/CommunitygDevelopment/forms/Engineering and
_WPO Forms/CGP_2019.pdf (Rev. 2) Addressed.
7. New: Include 2019 Notice of Termination form. Link:
http://www.albemarle.org/upload/ima2es/forms center/departments/Communily Development/forms/En ing eeringand
_WPO Forms/CGP_Notice _of Termination 2019 FINAL_201904.pdf (Rev. 2) Addressed.
Engineering Review Comments
Page 2 of 7
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17-404.
1. Provide a Pollution Prevention Plan using the Albemarle County template. (Rev. 1) Addressed.
2. 17-404A. 1: List all of the activities that may generate pollutants, including the period of home and r^�a
construction. Use the Albemarle County template. Include landscaping materials, fertilizers, etc. (Rev. 1)
Addressed.
3. 17-404.A.3: List all non-stormwater discharges that may co -mingle with stormwater. (Rev. 1) Addressed.
4. 17-404.A.4: Provide the name of the persons responsible for implementing the plan, practices and
procedures. (Rev. 1) Addressed.
5. 17-404.A.5: Describe the practices and procedures that will be implemented for spill/leak response. The
pollution generating areas appear to drain to the sedimentation basin. (Rev. 1) Not addressed. Provide
narrative describing spill /leak response consistent with refueling area depicted on plans /PPP Exhibit.
(Rev. 2, 2) Not addressed. Ref. county email, 11/25/2019 4:01 PM.
6. 17-404.A.6: Describe the procedures for providing pollution prevention awareness. (Rev. 1) Partially
addressed. Asfollow-up: Please describe how awareness is provided. For example: project initiation for
staff with duties that intersect VAR10; new staff on -boarding; once per week, etc. (Rev. 2) Addressed.
7. 17-404.B. Lb: Show how construction materials and construction waste will be protected from exposure to
precipitation and stormwater. (Rev. 1) Not addressed. SWPPP Sec. 6.C. table states material delivery and
storage is `shown on plans.' Revise PPP Exhibit to show location of material delivery and storage. (Rev. 2)
Addressed.
8. Address whether the site discharges to impaired waters, surface waters within an applicable TMDL
wasteload allocation or exceptional waters. (Rev. 1) Addressed.
9. Provide the names, telephone number(s) and qualifications of the Qualified Personnel. (Rev. 1) Addressed.
(SWPPP, Sec. 8, Scott Collins, PE)
New:
10. Show rain gauge on PPP Exhibit. (Rev. 2) Addressed.
11. Relocate concrete washout to CE side of RWD, or position near enough to the RWD such that concrete
chute extends over the RWD without vehicle tires damaging RWD. (Rev. 2) Addressed.
12. Please prepare /include Phase III PPP Exhibit. (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 disapproved for reasons listed below. The stormwater management plan content requirements can be
found in County Code section 17-403.
1. 17-405.A.2: Provide a Notice of Permit Coverage from DEQ when the coverage is obtained. (Rev. 1, 2)
Comment persists. Applicant acknowledges requirement.
2. Nutrient credits have to be purchased before the plans are approved. Section 17-502 provides the
requirements for acquisition of offsite nutrient credits. Provide the required documentation for the
purchased credits. Please contact Ana Kilmer before purchasing the credits. (Rev. 1) Addressed. 1.25 lb.
phosphorus nutrient credits purchased from Virginia Nutrient Bank, 8 Oct 2019. Also, Applicant email,
11/25/2019 9:37 AM.
3. 17-405.A.3: Provide a copy of the General Permit. (Rev. 1) Comment persists: See Sec. A.item 6, above.
(Rev. 2) Addressed.
4. 17-415: Submit the required stormwater control maintenance agreement. (Rev. 1, 2, 3) Comment persists.
Applicant response: `The developer is currently working on this.' (Rev. 3) Also, CE email, 11/22/2019
6:37 PM.
Engineering Review Comments
Page 3 of 7
5. 17-405.A.5:
a. The proposed doghouse VDOT MH-1 "STR Existing" shown on Sheet 8 profile is not labeled on
plan views. Label on all relevant plan views. Same comment for STR 2 VDOT DI-7. (Rev. 1)
Addressed.
b. Structure shown on "SWM Facility Section" as "STR: Existing VDOT MH-1" was described as a
headwall that will be replaced with a doghouse manhole. Clarify that the VDOT MH-1 will be
"New". (Rev. 1) Partially addressed. Applicant response (5.a., above): `...Please see the final
road plans for the design information ...for the remainder of the onsite storm sewer system and
proposed yard drains.' As follow-up: Although Road Plan will specify storm conveyance design,
with WPO Plan, please provide LD-229 for storm lines downstream of detention pond, including
western 24" DIA culvert beneath Berkmar Drive. The eastern 24" culvert is to be removed. (Rev.
2) Withdrawn. SWM basin 18" outfall conveys 25-yr event,without activating Spillway.
c. Label all SW structures. (Rev. 1) Addressed.
d. Label all existing culvert pipe diameters (Sheet 2 et seq.) (Rev. 1) Addressed.
e. Provide details for drop inlets and doghouse manhole. (Rev. 1) Addressed.
f Show a construction staging area. (Rev. 1) Addressed.
g. Show the flow line associated with each Tc. (Rev. 1) Addressed.
h. Show on the plans all information necessary to evaluate the accuracy of calculations, such as
where runoff becomes shallow and concentrated flows. (Rev. 1) Addressed.
i. It is unclear on what the Flow Length (TR55 Worksheet) figures for DA D (present) are based. 40
feet of "Dense Grass" and 75 feet of "Unpaved" are shown in the table. However, the longest
dimension between the structure and the paved road on TMP 45-86A is approximately 70 feet.
The bases for other data in the table are also not clearly supported. Please clarify. (Rev. 1)
Addressed.
j. The drainage areas on the Runoff Curve table pre- and post -development are not supported by the
drawings. E.g., in D.A. A, the gravel area (0.69 ac) appears in aerial photos to be actually much
larger than the area described as "Lawns in Good Condition" (1.02 ac). Please clarify. (Rev. 1)
Addressed.
k. Show how discharge from roof drains will be managed. (Rev. 1) Partially addressed. Applicant
Response: `Albemarle County Engineering has directed Collins Engineering in the past to have
townhouse building rooftops' runoff piped directly to yard drains or storm sewer when possible.
As a result, the proposed development incorporates an extensive network of yard drain inlets, yard
drain pipes, drop inlets and storm sewer. As a result, the subareas reflect this. Additionally, a note
has been added to the bottom left corner of sheet 10's plan for clarity, which states building
rooftop drainage will be collected and piped to the yard drains.' As follow-up: To clarify design
intent /ensure compliance, please: Label lots. Confirm all townhouse units roof runoff discharges
to a pipe system (i.e., no splash blocks). Roof leader line discharge is concentrated, not sheet
flow. Albemarle is dealing with intractable erosion behind single-family homes in a large
development where units discharge roof runoff to constructed slopes, rather than a dedicated storm
conveyance system. Also, items, below. (Rev. 2) Addressed. See sheet 12.
Show how stormwater flow in DA C (post -developed) will be controlled and directed along the
property line so that it reaches the SW management BMP. (Rev. 1) Partially addressed.
Applicant response: `The plan does not propose to direct subarea C to the stormwater management
facility. This runoff essentially drains down the embankment and sheet flows toward the proposed
intersection, where it is captured by a DI and routed to the existing outfall pipe to remain. Subarea
C is not part of the routing calculations and the water quantity requirements for channel and flood
protection are met without the detention of subarea C, which is mostly comprised of pervious
areas.' As follow-up: Post -developed subarea C appears to propose no collection behind units (no
yard drains). Subarea C DA splits townhouse units, suggesting roof release as concentrated flow
to slopes near development property line (PL). Proposed contours without yard drains behind a
Engineering Review Comments
Page 4 of 7
series of units indicate release will traverse slopes and exit development onto adjacent property.
Although calculations show subarea C does not require to be routed to the detention pond for
quality compliance, impact requirements apply. If design allows roof runoff to traverse slopes
behind units with no mechanism to convey subarea C runoff to existing outfall pipe that remains,
it will exit the property without reaching the pipe. Flow lines in subarea C are inconsistent with
proposed grade. Please: Label lots. Provide roof runoff conveyance for all portions of roofs of
units in subarea C or provide on -site facilities capable of transitioning concentrated roof runoff to
sheet flow. Regardless, proposed grade along downslope edge of development should mimic
Swale /ditch contours to divert runoff to existing outfall pipe. Experience with post -developed
conditions on projects reveals frailty of design unless care is taken to prevent offsite impacts from
runoff from units close to PLs. For this reason, review must ensure off -site impacts are negligible,
or nil. We request design focus on perimeter development subarea C units near Berkmar Drive.
(Rev. 2) Addressed. See sheet 12.
in. Clarify whether runoff is intended to cross the sidewalk to reach the inlet structure in DA C (Sheet
12). (Rev. 1) Not addressed. Applicant response: `Subarea C's runoff is sheet flow and is
intended to travel across the sidewalk and into the proposed drop inlet.' As follow-up: Design
requires revision. Runoff crossing walks freezes in winter, is problematic in other seasons. Please
revise proposal to ensure runoff does not cross sidewalks. Also, please see items k,1, for
discussion of post -developed grading, collection, and conveyance in subarea C. (Rev. 2)
Addressed. See sheet 10, 11.
n. VRRM Compliance Spreadsheet image quality is very poor and is illegible. Provide a legible
document. (Rev. 1) Addressed.
o. The post -development grading does not support flow to all of the yard grates. Clarify the grading
to ensure flow to yard grates. (Rev. 1) Partially addressed. As follow-up: Subarea C is
problematic. Provide collection /conveyance. Also, items, above. (Rev. 2) Addressed. See sheet
10, 11.
6. 17-405-A.6.g: Provide a requirement to minimize soil compaction. (Rev. 1) Addressed. Sheet 11, Note 5.
New:
7. Provide VODT IS-1 detail, inlet shaping. (Rev. 2) May persist. Include VDOT IS-1 detail on sheet 3A.
Restore sheet 3A to WPO plan set. (Rev. 3) Not addressed. Ref. county email, 11/25/2019 4:01 PM.
8. Sheet 11:
a. SWM facility profile:
Show 25-yr event storm elevation. Emergency spillway elevation is 0.09' below 100-yr
design storm. Design should prevent any but relatively infrequent release over the
emergency spillway. Likewise, Ex. 24" DIA culvert that remains beneath Berkmar Drive
should convey the 25-yr event in open flow condition to keep Berkmar Drive free of
flooding in the 25-yr storm event. (Rev. 2) Partially addressed. As follow-up: C5 SB 1
Section indicates 25-yr elev.=526.14 while CI I basin section indicates 10-yr elev.
=526.17 (10-yr basin > 25-yr. SB1 elev.). Please reconcile. (Rev. 3) Withdrawn.
ii. Provide SWM Facility base buoyancy calculations. (Rev. 2) Partially addressed. As
follow-up: Revise sheet 11 basin label (riser base dimensions) consistent with buoyancy
calculations base dimensions (9' X 9' X 2') and consistent with C5 Sediment Basin Sect.
Also, S. Collins email, 11/20/2019 5:18 PM, with attached buoyancy calculations. (Rev.
3) Persists.
b. Detention basin detail shows 10' wide grass -lined graded SWM Access. Please show transition to
roll-top curb for vehicle access. Provide roll-top curb detail with WPO and Road Plans. (Rev. 2)
Addressed.
c. Several references to 6" DIA orifices, either to be plugged watertight or to remain as permanent
low -flow orifice, require clarification that sediment basin profile may resolve. Are there multiple
6" orifices in SB-1 riser, for example. (Rev. 2) Addressed.
Engineering Review Comments
Page 5 of 7
d. Notes:
i. Provide Facility Construction Note that requires periodic or final reports to Albemarle
/Engineering as needed to ensure construction per design. Recommend note reference
Construction Record Drawing (As -built) for VSMP, Sheet 9. (Rev. 2) Withdrawn. See
iii, below.
ii. Embankment Notes: Add Note similar to 14.d.i.: Periodic /final geotechnical reports
verifying detention basin was constructed per design, sealed by a licensed PE. These
reports must include real-time inspection observations and compaction testing, per design
specifications. Albemarle cannot overstate the importance of facility performance
relative to Berkmar Drive, or effect or consequence of basin embankment failure. (Rev.
2) Withdrawn. See iii., below.
iii. General SWM Notes: Similar to i., ii., provide Note requiring Applicant /Owner to
furnish periodic /final construction field inspection /test reports to verify SWM facility is
constructed per design. Ref. Construction Record Drawing (As -built) for VSMP, Sheet 9.
(Rev. 2) Addressed. This note is sufficient.
9. Sheet 12: Provide video inspection for western -most 24" DIA culvert beneath Berkmar Drive, since there is
no other storm runoff conveyance from this proposed development. If existing condition of existing culvert
beneath Berkmar Drive is deficient, propose remedy. Ex. pipe must be in acceptable condition. (Rev. 2)
Addressed. Ref email, S. Collins, 11/21/2019 10:25 AM (photo).
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 disapproved for reasons listed, below. The erosion control plan content requirements can be found in
County Code section 17-402.
1. Provide a certification with the final plan, in accordance with County Code section 17-402.C.6. (Rev. 1)
Withdrawn. VMSP Application Sec. A. signature serves as certification.
2. Provide the name of the certified land disturber (17-402.C.4). (Rev. 1) Comment persists. Applicant
indicates RLD will be listed /SWPPP updated at pre -construction prior to Grading Permit issuance. (Rev.
2) Addressed. Sec. 8, SWPPP.
3. Provide the required I I" x 17" plan sheets (Section 4 of SWPPP plan). (Rev. 1, 2 3) Comment persists.
As follow-up: Please provide updated ESC plan sheet (SWPPP inserts), once review comments addressed.
4. Label the drainage area(s) draining to the sediment trap (17-402-C.5). (Rev. 1) Addressed.
5. The drainage area delineation reasoning is unclear. For example, one area is orphaned in the corner above
"TMP 45-86" label, and the drainage delineation lines are not perpendicular to grade lines nor along the
dike. (Sheet 5). (14-402-C-5). (Rev. 1) Addressed.
6. On Sheet 6: (Rev. 1) Addressed.
a. The same D.A. delineation comment applies.
b. Sheet 6: The dogleg to the right of `BM" is unexplained. It appears on all sheets.
c. The diversion dike crosses the D.A. line at the PPP location. Please revise.
d. The sequence of construction is not consistent with the note on Sheets 5 and 6 stating that the
contractor will construct a construction entrance "later". Please revise to clarify the construction
entrance sequence and compliance in all E&S phases.
7. Once constructed, the yard grates will require protection from the entrance of pollutants. Revise to show
protection. (Rev. 1) Addressed.
8. Provide topo line labels on Sheet 7, in the match line inset showing offsite sanitary sewer connection. (Rev.
1) Addressed.
New:
Engineering Review Comments
Page 6 of 7
9. Sheet 4:
a. Revise /replace cross -contour SF; propose alternative ESC measures. SF is installed parallel with
contours. (Rev. 2) Addressed.
b. Provide SB-1 profile. (Rev. 2) Addressed.
c. Provide SB-1 calculations (sheet 5). (Rev. 2, 3) Partially addressed. As follow-up: Sediment
basin indicate baffles: `YES' but baffles not shown in plan view, C7. Please reconcile.
d. Revise ESC legend to include BM ( ++++ ) (Rev. 2) Addressed.
e. Revise 9.27 Ac. LOD label to read 9.69 Ac., consistent with other plan sheets. (Rev. 2)
Addressed.
f. Relocate emergency spillway off fill slopes, or construct using nonerodable material such as
riprap. Ref. VESCH, pg. III-86. (Rev. 2) Not addressed. (Rev. 3) Not addressed. Ref county
email, 11/25/2019 4:01 PM.
10. Sheet 5:
a. Provide sediment basin calculation, upper right /inset. (Rev. 2) Addressed.
b. Lower right: revise match -line label. (Rev. 2) Addressed.
c. Label ST-1 floor dimensions. (Rev. 2) Addressed.
11. Sheet 6:
a. Include VESCH Plate 3.14-6. Provide note that indicates top of baffle must extend from floor of
sediment basin to 6" above riser crest elevation. (Rev. 2, 3) May persist. See item 9.c., above.
b. Show baffles in sediment basin profile, SB floor to 6" above riser crest elevation. Ensure vertical
profile is scaled. (Rev. 2, 3) May persist. See item 9.c., above.
c. Label ST-1 floor dimensions. (Rev. 2) Addressed.
12. Sheet 7:
a. Provide RWD at Berkmar Drive, ESC Phase III. (Rev. 2) Addressed.
b. Provide runoff catchment for RWD at Berkmar Drive. It is imperative that sediment /stone not
wash into Berkmar Drive during any phase of development, since a heavily -trafficked corridor.
(Rev. 2) Addressed.
c. Check to ensure that western -most existing 24" DIA culvert beneath Berkmar Drive is shown. It
appears line to be removed is shown. (Rev. 2) Addressed.
d. Provide deed bk.-pg. ref. for Ex. 20' San. Sewer Easement. (Rev. 2, 3) Not addressed.
13. Sheet 8:
a. Provide additional proposed and existing contours. (Rev. 2) Addressed.
b. Provide gated access through chain link fence to each cemetery, post -development. (Rev. 2)
Addressed.
c. Label lots. (Rev. 2) Addressed.
d. Confirm with Planning that a second entrance /connection with Woodburn Road is not required.
Woodburn Road seems a logical second point of access to Berkmar Overlook development. (Rev.
2) Withdrawn. Defer to Planning /Site Plan Review.
e. Provide post -developed topsoil Note /VESCH specifications for areas proposed to be lawn, or turf.
4.1 Ac. of pre -developed site is reported to be a gravel industrial site, with additional soil roads.
(Rev. 2) Partially addressed. As follow-up: Appears only note is sheet 3, Permanent
Stabilization: Top Soil — 2 "; this note may be overlooked. Recommend a prominent Note. (Rev.
3) Withdrawn.
Engineering Review Comments
Page 7 of 7
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 have 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 have to be completed by the owner and submitted along with cash,
certificates or sureties for the amounts specified. The agreements will have 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 have 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 have to be submitted along with court recording fees.
After bonding and agreements are complete, county staff will 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 have 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 must 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 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;
httt): //www. albemarle. org/dei)tforms. asp?department=cdenewDo
WP0201900050 Berkmar Overlook 112519rev3