HomeMy WebLinkAboutSDP201800061 Review Comments Minor Amendment 2018-11-26COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road, Room 227
Charlottesville, Virginia 22902-4596
Phone (434) 296-5832 Fax (434) 972-4126
Site Plan Review
Project title:
ACSA Admin & Ops Center —Minor Amendment
Project file number:
SDP201800061
Plan preparer:
Dewberry Engineers / 4805 Lake Brook Drive, Suite 200
Glen Allen, VA 23060
Owner or rep.:
Alexander J. Morrison, PE /ACSA [amorrison@serviceauthori , .org]
Plan received date:
7 Aug 2018
(Rev. 1)
21 Nov 2018
Date of comments:
10 Sep 2018; rev. 13 Sep 2018
(Rev. 1)
26 Nov 2018
Plan Coordinator:
Andy Reitelbach
Reviewers:
John Anderson
SDP201800061
1. A separate standalone VSMP permit is required. Please remove the following from the Minor Site
Plan Amendment: C0.2; portion of C2.0 related to ESC; C5.0, C5.1, C6.2, C6.3. (Rev. 1)
Addressed.
2. Recommend revise title of Minor Site Plan Amendment to include `SDP201800061, Minor Site
Plan Amendment' and to delete `100% submission.' (Engineering recommendation only). (Rev.
1) Addressed.
3. Title VSMP Plan: `Albemarle County Service Authority Operation Center Expansion Parking Lot
Expansion, VSMP /WP02018-XXXXX.' Note: once WPO# assigned, will provide # for final
VSMP Plan title sheet revision. (Rev. 1) Addressed. WP0201800068 (revised) received
11/21/18 is under review.
4. Ref. Albemarle County Code, Chapter 17, Sec. 17-401 thru 17-405 for VSMP Application form
and content requirements (incl. SWPPP, PPP, ESC /SWM plans + Application /fee requirements).
Link:
http://www.albemarle.org/oload/images/Forms Center/Departments/County Attorney/Forms/Albemarle C
ounty Code _Ch17_Water _Protection.pdf (Rev. 1) Addressed. Applicant response: `Form and
content requirements will be reviewed and used.'
5. C3.1 —Label ditch and ditchline slope on upslope side of retaining wall. (Rev. 1) Addressed.
6. C3.1 — Recommend revise description of Str. 20 (in data arranged as table) to include 48" diameter.
(Rev. 1) Addressed.
7. C3-2P-ropos€d retaining wall designproblematic: (Rev. 13-Sep) After further consideration of
18-30.7.5 design standards, plan review, and discussion, a combination of grade at base of wall not
to exceed 2:1 and wall height not to exceed 6' is permissible; however, revised design must
eliminate angle at top of 2:1 fill slope. Option recommendation: provide min. F wide bench, 1-2%
slope away from base of wall. ACSA to coordinate slope -grade design revision with Dewberry.
Further, Dewberry is encouraged to consider stabilization matting for existing drainage way at base
of wall /base of 2:1 slope that will likely be in proposed fill section, and susceptible to erosion.
a. Proposed design must meet each annlicable standard listed at 18-30.7.5.a.1-3, b.l-4;
please call if any questioi. (Rev. 1) Addressed.
b. Eliminate prepesed 11 slope at base of wall, an impefmissible appr-aaeh to limiting
Engineering Review Comments
Page 2 of 3
height te (Rev. 13-Sep) Comment withdrawn.
e. Provide stepped walls max. ht. -6', vA ith 3' separatiofl between walls.
d. Consider constructability /possible need for off -site temporary construction easement.
(Rev. 1) Addressed. Note: a temporary construction and permanent maintenance
easement have been added to sheet C3.1.
e. Proposed design (w/ 2:1 slope at toe, to be eliminated) requires 6' horizontal space; 4.5'
is available between face of wall and property line. (Rev. 1) Addressed. Note: An
easement agreement will be obtained with the abutting parcel owner.
f. Show property line (accurate scale) in profile view. (Rev. 1) Addressed.
g. it appears possible to Feeonfigtife wall design and par -king lot to ineet design standaF
listed at 19 30.7.5 while still pFoviding 18 par -king spaees. RevieweF is tinaw-ar-e of any
C4.0
8. Revise STM 24 MH-1 label (typo) -diameter should read 60". (Rev. 1) Addressed.
9. Provide Note that steps are required for MH depth > 4.0'. (Rev. 1) Addressed.
10. Compare inside crown of pipe elevation, 375.75 (INV IN, STM 20), with 10-yr event elevation,
376.52. Detention pipe must be sized to contain a 10-yr event without exceeding interior elevation
(of top of pipe, at lowest point). Avoid pressurized system. Recommend examine next larger pipe
diameter. (Rev. 1) Addressed.
11. STM20 - Provide ref. to weir plate detail, sheet C5.3. (Rev. 1) Addressed.
12. C4.1 - Conduit flex table slope and length values for Node # 25, 30 do not match profile labels,
C4.0, C4.1. Review /revise for consistency. (Rev. 1) Addressed.
13. 5.2 - Recommend detail for handrail post, since detail provided assumes handrail set in retaining
wall. Proposed handrail is not on wall, but behind wall, in fill section. Also note: handrail design
must prevent easy access to top of wall. If rail slopes down with grade behind wall, ensure design
provides suitable deterrent to trespass /prevents access to top of wall. (Rev. 1) Addressed.
14. C5.3 - Show MH steps schematically in top view of weir plate MH detail, to limit conflict and
guide installation during construction. (Rev. 1) Addressed.
15. C5.3 - Provide VDOT ST-1 (MH step) detail. (Rev. 1) Addressed.
16. C5.3 - Provide trash rack, 4" orifice. (Rev. 1) Addressed.
VSMP (preview comments); additional comments likely, once VSMP Application submitted: (Rev. 1)
WPO under review. Comments 17. -27. and comment responses will be shared with WPO reviewer.
17. C0.2, ESC Maintenance /Note. 2: Revise to specify paved construction entrance. Provide paved
CE detail. Ref. ACDSM /p. 8 -link:
httD://www.albemarle.or2/UDload/ima2es/forms center/departments/communitv development/forms/design s
tandards_manual/Albemarle _ County Design Standards _Manual _2015-04-25_draft.pdf
18. C0.2, ESC Sequence item 4 must come prior to item 3; install silt fence prior to clearing /grubbing.
19. C2.0 -Revise CE label to read PCE (Incl. PCE in ESC legend).
20. Provide schematic depicting Phase 2, once retaining wall constructed and STM25 installed. See
ESC Sequence note 6 (storm structure #25). Provide phased ESC schematic.
21. In Phase 2 ESC schematic, specify VESCH blanket stabilization for ditch behind (upslope side of)
retaining wall to limit proximate effect on adjacent property, should erosion develop in this area.
22. C5.0 - Provide paved construction entrance detail -ref. p. 8, ACDSM; also, comment 17, above.
23. C6.2 - Coordinate nutrient credit purchase with Ana Kilmer, Management Analyst, CDD, prior to
purchase. Legal must review documents prior to sale. Ms. Kilmer: 434.296-5832 -x3246
/akilmer(c�r�,albemarle.org. (Rev. 13-Sep) ACSA has purchased credits; will work with Albemarle to
address any outstanding nutrient credit purchase document (VSMP) needs or requirements.
24. C6.2 -Provide stormwater quality /quantity narrative to outline and demonstrate compliance.
25. C6.3 -Energy balance is incomplete, and confusing. Provide RV(1_y, pre- /post_develppment).
26. C6.3 -Provide routing for 1-year event, pre -development; provide model input /hyrdrograph.
27. Use county SWPPP template.
Link:
http://www.albemarle.ora/upload/images/forms center/departments/Community Development/forms/Engine
Engineering Review Comments
Page 3 of 3
ering and _WPO_Forms/Stormwater Pollution Prevention Plan SWPPP template.pdf
Thank you.
J. Anderson 434.296-5832 -0069
SDP201800061 ACSA Admin Parking 112618 rev l .docx