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HomeMy WebLinkAboutWPO201600018 Review Comments WPO VSMP 2016-04-13COUNTY 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: Castalia Pond (ESC) / Mitigation Plan Plan preparer: Lauren Gilroy/Justin Shimp, Shimp Engineering, 201 E. Main St. Suite M, Charlottesville, VA 22902 f iustin(&shimp-enizineering com] Owner or rep.: Castalia-Cismont Investment LLC, 200 Garrett St., Suite S Charlottesville, VA 22902 Plan received date: 18 Mar 2016 Date of comments: 13 Apr 2016 Reviewer: John Anderson WP0201600018 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. Ref. Sec. D. item #6, 7, below. B. VSMP: SWPPP: Stormwater Management Plan (WP0201600018) VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or disapprove a SWMP. This plan is PENDING. The stormwater management plan content requirements can be found in County Code section 17-403. 1. Ref. Sec. D. item #6, 7, below. C. VSMP: SWPPP: Erosion Control Plan (WP0201600018) Virginia Code §62.1-44.15:55 requires the VESCP authority to approve or disapprove an ESCP. This plan is disapproved for reasons provided in comments below. The erosion control plan content requirements can be found in County Code section 17-402. Ref. Sec. D. item #3, 4, below. D. Mitigation Plan (WP0201600018) 1. Confirm design intent to establish buffers for intermittent/perennial stream not presently shown on county GIS layer. Albemarle County will visit site upon request, but does not ordinarily take initiative in cases where topographic features not shown as streams in on-line GIS system may be impacted by a project proposal. This signals no reticence to enforce ordinance, nor does it relieve Applicants of 17-600.13. requirements: Engineering Review Comments Page 2 of 4 ARTICLE VI, STREAM BUFFERS Sec. 17-600 Extent of stream buffers; retention and establishment. Except as provided in section 17-602, each erosion and sediment control plan and each VSMP permit shall provide for stream buffers for the purposes of retarding runoff, preventing erosion, filtering nonpoint source pollution from runoff, moderating stream temperature, and providing for the ecological integrity of stream corridors and networks, as provided herein: A. Development within a development area. If the development is located within a development area, stream buffers shall be retained if present and established where they do not exist on any lands subject to this chapter containing perennial streams, contiguous nontidal wetlands, or both. The stream buffer shall be no less than one hundred (100) feet wide on each side of any perennial stream and contiguous nontidal wetlands, measured horizontally from the edge of the contiguous nontidal wetlands, or the top of the stream bank if no wetlands exist. B, Development within a water supply protection area or other rural land. If the development is located within a water supply protection area or other rural land, stream buffers shall be retained if present and established where they do not exist on any lands subject to this chapter containing perennial or intermittent streams, contiguous nontidal wetlands, and flood plains. The stream buffer shall extend to whichever of the following is wider: (i) one hundred (100) feet on each side of any perennial or intermittent stream and contiguous nontidal wetlands, measured horizontally from the edge of the contiguous nontidal wetlands, or the top of the stream bank if no wetlands exist; or (ii) the limits of the flood plain. The stream buffer shall be no less than two hundred (200) horizontal feet wide from the flood plain of any public water supply impoundment. C2 —GIS shows stream buffer for stream located 275' E of Ex. Riding Ring. Area further east, shown with buffer disturbance =61,459 sf, does not appear with stream buffer in county GIS. 2. Ref. Attached Riparian Buffers Guidance Manual, Table B/Option C. C. Ifthe applicant is willing to enter into a five year maintenance and performance guarantee: 100% of buffer planted with: Bare root seedlings or whips at 1,210 per acre, approximately 6'x 6' on center (Minimum survival required after two growing seasons: 600 plants) or Container grown seedling tubes at 700 per acre approximately 8'x 8' on center (Minimum survival required after two growing seasons: 490 plants) C2 —Please include reference to five year maintenance and performance guarantee. 3. C3 —Include stream bypass design required to protect downstream stream water quality during dam construction. Provide graphic depiction of perennial/intermittent/ephemeral stream bypass. 4. C4 —Provide narrative sequence to ensure the same (item #3). For example, one option is to place bedding for 50 LF 30" RCP through -dam pipe, divert stream into 50' pipe, construct dam with no stream water quality impact, then, during clear weather, use coffer/pump techniques to construct the 42" DIA RCP standpipe. Recommend detailed stream bypass/dam construction sequence after Phase 1 sequence notes. 5. If streams or wetlands exist, acquire applicable state/federal permits or review clearances. 6. With land disturbance >10,000 ft2, project is subject to the VESCP and VSMP unless Applicant claims exemption under 17-301.G.; 17-303.B. (Agricultural Pond). Without exemption, ESOP, VSMP Permit Application, General VPDES Permit registration statement, and SWPPP are required. 7. 17-304.A. requires the VSMP Administrator to determine whether an activity is subject to Chapter 17. The 1.5 Ac. proposed pond appears to qualify for exemptions at 17-301.G., and 17-303.B. Albemarle County requests Applicant provide narrative supporting exemption. Narrative should focus on agricultural purpose. If no agricultural purpose is served, project proposal does not qualify for exemption. 8. C4 —Recommend include dam construction notes; for example: Engineering Review Comments Page 3 of 4 DAM 0769MnON NOTES GEOTECHNICAL CONSULTANT TO SPECIFY DAM EMBANKMENT MATERIAL, SEEPAGE CONTROL DEVICES, CUT—OFF TRENCH DESGN, CULVERT EED04NG REQUIREMENTS. AND OTHER APPROPRIATE GEOTECHNICAL DESIGN REQUIRIEMENTS. FOUNDATION AND ABUTMENT AREA EXTENDING 10' BEYOND DAM FOOTPRINT SHALL BE CLEARED, GRUBBED Ac STRIPPED OF ALL VEGETA11p TOPSOIL 00/0R ORGANIC SOIL & OTHER UNSUITABLE MATERIALLS, AFTER CLEARING, GRUBBING. STRIPPING AND REMOVING ANY OTHER UNSUITABLE MATERIALS, THE SUBGRADE SHALL BE PROOFROLLEU WITH COIPACTION EOUIPMENT UNDER THE OBSERVATION OF A QUALIFIED ENGINEER- THE COMPACTION EQUIPMENT SHOULD BE THE HEAVIEST POSS UI -E EQUIPMENT THAT WILL NOT CAUSE DISTURBANCE OF SUITABLE SUBGRADE SOILS, EXCESSIVELY SOFT OR UNSUTASL E MATERIALS SKALL BE REMOVED AND REPLACED WITH COMPACTED FILL WHERE ROCK IS EXPOSED AFTER STRIPING OR UNDERCUTTING, ALL LOOSE ROCK MATERIAL SHALL 13E REMOVED PRIOR TO PLACING COMPACTED FILL, R" SUBGRADES SHALL BE INSPECTED AND APPROVED BY THE INSPECTOR OR ENGINEER PRIOR TO PLACEMENT 4W FIH COMPACTED FILi, SHALL NOT BE PLACED PRIOR TO PERFORMING THE REQULRED FOUNDATION AND ABUTMENT PREPARATION, OR ON ANY F'ROZEH SURFACE CMAPACTED FILL SHALL EXTEND TO THE rILL LIMIT LINES AND GRAOES INDICATED BY THE APPROVED OONSTRUCTION PLAN, COMPACTED FILL MATERIAL SHALL BE OF THE TYPE CLASSIFICATION SYMBOL SPECIFIED BY THE GEOTECHNICAL CONSULTANT. OR OF A BETTER OUALJTY MATERIAL AS DEEMED By THE UNIFIED SOIL CLASSIFICATION SYSTEM, ALSO, RESTRICTIONS ON THE LIQUID LJMITS AND PLASTLOTY INDEX OF THE MATERIAL MAY EIE INCLUDED WHERE APPLICABLE, COMPACTM FILL SHALL CONSIST of MATERIAL FRIG OF ORGANIC MATTER. RLIBBISH, FROZEN SOIL, SNOW. ICE. PARTICLES WITH SIZES LARGER THAN 3" OR OTHER DELETERIOUS MATERIAL COMPACTED FILL SHALL BE PLACED IN HORIZONTAL LAYERS Of S' TO 12* IN LOOSE THCCKNESS, ACTUAL LIFT THICKNESS WILL BE SPECIFIED BY THE GEOTECHNLCAL CONSULTANT. THE= MC4STURE CONTENT SHALL BE CONTROLLED SUCH THAT COMPACTION IS ACHIEVED WITHOUT 11E LDING OF THE SURFACE EACH LAYER SHALL BE UNIFORMLY COMPACTED WITH SUITABLE COMPACTION EQUIPMENT TO AT LEAST 95X OF STANDARD PROCTOR MAXIMUM DENSITY IN ACCORDANCE NTH AST} 0-658, AASHTO T-99, OR VOOT SPECIFICATIONS, ANY LAYER OF FINE GRAINED FILL WHICH BECOMES SMOOTH UNDER COMPACTION OR CONSTRUCTION TRAFFIC SHOULD BE SCARLFIET} TO A DEPTH OF 2' TO ALLOW ADEQUATE BONDING BETWEEN LAYERS, COMPACTED FILL WITH A MOISTURE CONTENT WHICH WILL NOT PERMIT COMPACTON TO THE SPECIFIED DENSITY STANDARD SHALL BE SCARIFILO DRI»} OR WETTED AS NECESSARY TO PERMIT PROPER COMPACTION. Process: (typical —this may vary depending on Applicability of VESCP/VSMP requirements to this project. —ref. item #7, above) 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 and Mitigation Plan 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 Engineering Review Comments Page 4 of 4 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; http://www.albemarle.org/deptforms.asp?department--cdengwUo Thank you. 434.296-5832 —0069 File: WP0201600018 Castalia Pond 041316