CASE / PERMIT # GREENVILLE COUNTY, SC STORMWATER MANAGEMENT/SEDIMENT CONTROL CHECKLIST DISTURBING 1 ACRE

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1 _ GREENVILLE COUNTY, SC STORMWATER MANAGEMENT/SEDIMENT CONTROL CHECKLIST DISTURBING 1 ACRE r MORE AND/OR INCREASING FLOWS BY 1 CFS r MORE Please nte that if we d nt have r receive the crrect infrmatin and/r supprt dcumentatin, we cannt prcess yur prject submittal and yu will be ntified via t re-submit fr review. Prject Overview 1. GENERAL DOCUMENTS Plan Submittal Master Flder t include the fllwing files (All fees must be paid prir t acceptance f submittal) 1. Greenville Cunty Applicatin, cmpleted in its entirety (PDF) 2. SCDHEC NOI Applicatin (PDF) 3. Strmwater Management / Sediment Cntrl Checklist (PDF) 4. Primary Permittee Acknwledgement (PDF) 5. Transmittal Letter (PDF) 6. Rad Review Checklist (if Cmb Review) (PDF) 7. Remediatin Certificatin Frm (PDF) 8. Registered Engineer s Seal & Engineering Firm s Certificate f Authrizatin (On Plans and Reprt) 9. SWPPP / Strmwater Reprt (8.5x11 frmat) (PDF) a) Table f Cntents b) Narrative c) TMDL / 303d Impaired Waterbdies d) Sils Reprt including maps e) FEMA Map f) Phtgraphy f site g) 360 Pre and Pst Develpment Maps (Individual PDF s t be including in the reprt) h) All ther maps in frmat ther than 8.5x11 (PDF) (Explain) i) Cmmercial Traffic Study ( If required) j) Calculatins t supprt 80% trapping efficiency during cnstructin (SEDCAD, Design Aids) (Prvide PDF and sftware data files) k) Calculatins fr peak rate analysis (Hydraflw, SEDCAD, etc.) (Prvide PDF and sftware data files) l) Calculatins t shw hw site will meet 85% f Ttal Suspended Slids (TSS) based n annual lading (IDEAL) (Prvide PDF and sftware data files) m) Manufacturers Infrmatin n MTD s, LID s, Undergrund Detentin r ther specialty BMP s. (PDF) n) Calculatins fr all cnveyance measures and stable channels (Prvide PDF and sftware data files) ) Calculatins fr all dissipater s and utlet prtectin (Prvide PDF and sftware data files) NOTE: All sftware data files t be in a sub flder within the master permit flder. Label each set f files in the sub flder fr Hydrlgy, Sedimentlgy and Pst Cnstructin Water Quality. 10. Cnstructin Plans (Prtfli Frmat) watershed maps fr Pre & Pst develpment, separate uplad frm reprt ( See page 3 fr details) Clseut Package Must Cntain 1. Certificatins (PDF) 2. As-Builts (PDF) 3. Clse Out Dcumentatin (PDF) 2. PROJECT NARRATIVE Scpe f prject utlined, including a brief descriptin f pre- and pst-develpment cnditins. Narrate hw the key elements f the Cunty Ordinance will be addressed and with what feature: Peak Rate Sedimentlgy if disturbing mre than 5 acres, narrate phases and transitin f phases Pst Cnstructin Water Quality Include a summary table f pre- and pst-develpment flws (at least 2-year, 10-year, 25-year and 100-year 24-hur strm events) If internal drainage system designed fr the 10-yr strm, narrate hw strmwater up t the100-yr strm will be cnveyed t the strmwater feature. Narrate dwnstream impact. Narrate TMDL/303d infrmatin. Include Strmwater Facility Ownership and Maintenance Infrmatin, including maintenance requirements fr each feature Page 1 f 11 Revised: March 2017

2 Existing flding prblems in the surrunding area described. If utside agency permits are required (SCDHEC, ACOE, etc.), narrate scpe f permit with respect t the prject If LID methds used, utline methd used, identify the LID methd and its benefits and impacts Include disturbed area calculatins included fr subdivisin prjects r LCP disturbing 1 r mre acres in the narrative and n the plans Fr subdivisins - If the site is nt t be mass-graded, the fllwing frmula shuld be used t determine the amunt f disturbance: Amunt f Disturbance = 2[Max Restricted Building Size][Number f Lts) + Right f Way (ROW) areas {ROW areas include clearing fr rads, utilities, easements etc.} If this equatin is used, include a nte n the plans stating: "The site is nt t be mass-graded. Only 2 times the ftprint is t be cleared as the lts are develped. The assumed disturbance n each lt is _ sq. ft. 3. TMDL/303d IMPAIRED WATERBODIES List the nearest S.C.DHEC Water Quality Mnitring Statin (WQMS) that the site's strmwater discharges drain t and the waterbdy n which it is lcated (), and prvide 303d map f site area. Qualitative and quantitative assessment (described in Sectin 3.4C f SCR100000), if nearest WQMS listed n the mst current 303(d) List f Impaired Waters and if site's strmwater cnstructin discharges cntain the pllutant f impairment and if site disturbs 25 r mre acres. Evaluatin f selected BMPs if nearest WQMS listed n the mst current 303(d) List f Impaired Waters and if site's strmwater cnstructin discharges cntain the pllutant f impairment and if site disturbs less than 25 acres Fr Impaired Waters discharge cmpliance (fr sites disturbing 25 r mre acres), the IDEAL mdel used t calculate the annual lading fr the pllutant f cncern fr pre-develped cnditins as a baseline and fr develped cnditins (with n increase) If Apprved TMDL develped fr nearest WQMS and if site's strmwater cnstructin discharges cntain the pllutant f impairment, shw the measures and cntrls n SWPPP met assumptins and requirements f TMDLs (may need t cntact Watershed Manager fr assistance). Fr mnitring statins with an Apprved TMDL, IDEAL mdel used t demnstrate that the annual pllutant f cncern lading fr the site in develped cnditins was reduced by the respective amunt as cmpared t the pre-develped cnditins. Pllutants f cncern include TURBIDITY, BIO (Macrinvertebrate), TP (Ttal Phsphrus), TN (Ttal Nitrgen), and Chlrphyll- A. Fr TURBIDITY, BIO(Macrinvertebrate) cnsider inclusin f BMPs t reduce sediment lad such as: sediment traps and basin designed t meet 80% sediment remval efficiency (regardless f size), additinal measures t stabilize site, limited clearing and grading Fr TP (Ttal Phsphrus), TN (Ttal Nitrgen), and Chlrphyll-A cnsider inclusin f BMPs t reduce nutrient lad. This culd include limited clearing and grading, sil samples fr t determine nutrient requirements during grassing Nte: Cntact staff fr guidance n selectin f BMPs based n pllutant f impairment Site Maps 4. PLANS Lcatin Map Nrth arrw and scale. Scale nt less than 1 = 1 mile. Adjining lakes, streams r ther majr drainage ways and assciated fldplains. Outlined prject lcatin. Labeled rad names adjacent t the site. Cnstructin Plans Scale n mre than 1 = 50 Nrth arrw and bar scale. 24 x 36 Sheets 5. USGS TOPOGRAPHIC SITE MAP & COUNTY GIS USGS Prject bundary utlined Rute f runff frm site t nearest waterbdy shwn Rad names adjacent t site labeled Page 2 f 11 Revised: August 2016

3 Cunty GIS Prject bundary utlined with 4 ft cntur Rute f runff frm site t nearest waterbdy shwn Rad names adjacent t site labeled 6. SOILS INFORMATION Prject bundary utlined Predminate sil types fund at the site identified n the plans r n a separate map Nte: Sils infrmatin is available frm the Natural Resurce Cnservatin Service thrugh their website: 7. FLOODWAY MAPS/FEMA FLOOD INSURANCE MAP Prject bundary utlined, if in clse prximity t fldplain/fldway 8. Hydrlgy Input Data Maps, the 360 Watershed Maps & Hydrlgy Input Data 24 x 36 frmat Areal 360 Watershed Map with all adjining prperties arund site (see: Areal Hydrlgy 360 Watershed Map frmat n LDD website under the permitting and frms tab) (Legible/scalable) Pre and Pst Develped site cnditins maps (at a measurable scale) On the 360 map prvide an analysis pint fr the utfall f the site fr pre and pst develpment, als prvide n the 360 map the verall watershed analysis pint that was elected in the pre design meeting fr pre ad pst develpment. The site and verall watershed analysis pint was mdeled and is cnsistent with hydrlgy mdel and watershed maps. On the 360 map shw delineated drainage areas and flw paths/netwrk diagrams that area scalable/measurable. 360 Drainage area maps that clearly crrespnd t the calculatins (pre- and pst-develpment) Prvide a chart n the map that encmpasses the fllwing infrmatin: CN s, TC, slpes, cnturs, flw path segment, Drainage Area Bundary (pre and pst develped). Sheet flw n greater than 100 feet. Naming cnventins must be cnsistent thrughut netwrk diagrams, mdels, narrative and plans Phtgraphy Sedimentlgy 9. SEDIMENTOLOGY Prvide Drainage Area Map utlining the area cntributing t each sediment basin, trap r rck sediment dike Sediment basins required fr sites with 5 acres r mre disturbed acres draining t ne pint Trapping efficiency calculatins shwing that all sediment basins/traps are capable f achieving a sediment trapping efficiency f at least 80% fr the 10-year, 24-hur strm event under disturbed cnditins, disturbing mre than 1 acre r mre.. Designers may use 0% dead space when using Baffles. Sediment basins prvide strage fr the 10-year, 24-hur strm event fr disturbed cnditins Sediment basins prvide 3600 ft³/ttal strage per acre draining t the basin Sediment traps are nly used fr drainage areas f less than 5 acres Sediment trap prvide 1800 ft³/ttal acre draining t each trap belw the spillway The Cunty requires installatin f sediment frebays at each utfall int the multi-purpse basin r sediment basin. Fr sediment traps, prvide peak utflw, q p, calculatins ensuring 80% trapping efficiency fr the 10-year, 24-hur strm event fr cnstructin cnditins and nt vertpping the trap's spillway Curve Number fr cnstructin analysis needs t reflect cnstructin/ disturbed cnditins. Curve Numbers fr newly-graded areas are: Hydrlgic Sil Grup A : 77 Hydrlgic Sil Grup B : 86 Hydrlgic Sil Grup C : 91 Hydrlgic Sil Grup D : 94 Sediment basins and traps designed fr ttal area draining t them Cpies f figures used t determine V15 (SV-1) and trapping efficiency, if Design Aids are used t determine trapping efficiency (See Design Manual) Sediment basins must dewater via an utlet structure that pulls water frm the surface. Optins fr this include skimmers and flashbard risers. Surface dewatering is nt required fr traps. Page 3 f 11 Revised: August 2016

4 During cnstructin, mass graded sites disturbing 10 acres r mre must fllw Peak Rate Attenuatin During Cnstructin Plicy Fr temprary sediment basins: Utilize a temprary sediment basin riser cnfiguratin. Design a primary riser cnsisting f a slid riser with n staged discharges r lw flw rifices. Design the basin s strmwater runff enters the primary riser by vertpping the riser structure and thrugh a Flating Skimmer. Design the riser t have a Flating Skimmer attached t the bttm f the riser dewatering the runff vlume belw the tp elevatin f the riser in a time perid ranging between 24 t 72 hurs. Prvide calculatins r design aids shwing that this basin will meet a minimum 80% trapping efficiency. Design a stabilized Emergency Spillway that safely passes the 100-year 24-hr strm event with a minimum ne-ft f freebard frm the 100-year 24-hur water surface elevatin t the tp f the dam. Prvide stable cnveyance fr 2, 10, 25, and 100 yr strm flws frm sediment basin Prus baffles must be prvided in sediment basins. Designers may use 0% dead space when using Baffles. Frebays must be installed, unless infeasible Public Safety shuld be taken int cnsideratin as a factr in design f sediment basins. Alternative BMPs must be utilized where a cnstructin site limitatins wuld preclude a safe design Nte: Cnsult the Greenville Cunty Strmwater Design Manual fr infrmatin n the design f these and ther devices Nte: The Design Aids in the BMP Handbk cannt be used t determine trapping efficiencies fr structures in series. If the flw fr the 10-year, 24-hur strm fr cnstructin cnditins vertps the structure r the structure's spillway, then the Design Aids cannt be used. Nte: If multiple sil types are in the area draining t the structure, then the sil type with the smallest D15 fr the apprpriate depth shuld be used t determine the settling velcity, V15; an average D15 shuld nt be used. Nte: SEDCAD users please refer t the mem regarding the input f utlet structures ( Nte: Silt fence nly used in areas with drainage areas f less than ¼ acre per 100 LF f fence and nt used in areas with cncentrated flws Nte: 80% trapping efficiency is t be met by treating sediment laden strmwater prir t entering buffer areas 10. FLOW CONTROL Cntrl strmwater vlume and velcity within the site during cnstructin t minimize ersin within the site Cntrl strmwater rates and vlume at utlets during cnstructin t minimize ersin t dwnstream channels and stream banks Peak Attenuatin Hydrlgy 11. HYDROLOGIC ANALYSIS Pst-develpment discharges must be less than pre-develpment discharges fr each utfall pint fr the 2, 10, and 25-year strm events (if nt, then see "Detentin Waiver" sectin belw); analyze the 100 year strm fr dwnstream impact at each utfall pint (Gilder Creek Watershed attenuatin t the 50-year strm required; City f Mauldin attenuatin t the 100- year strm required Freebard criteria is the same fr all required strm events). Pre- and pst-develped, with and withut detentin, hydrlgic analysis calculatins fr the 2, 10, 25 and 100 year, 24-hur strm events at each utfall pint Netwrk Diagram and Calculatins that clearly crrespnds t the infrmatin in Sectin 8. drainage area maps (pre- and pstdevelpment) Analysis pints fr cmparing runff rates fr the site and verall watershed shuld nt change frm pre t pst develpment. Drainage areas in watershed have nt shifted Analysis perfrmed using SCS 24-hur strm (Ratinal methd is nt acceptable) Rainfall Data frm Greenville Cunty Design Manual used in all calculatins 12. DETENTlON ANALYSIS/DESIGN Analysis Existing and planned drainage patterns, including ffsite areas that drain thrugh the site Pnd ruting using a vlume-based hydrgraph fr the 2, 10, 25, 100 year strm as required, SCS 24-hur strm event (SedCAD, HYDRAFLOW, etc. perfrm full pnd rutings; TR55 des nt perfrm a full pnd ruting; ratinal methd cannt be used) Page 4 f 11 Revised: August 2016

5 Hydrlgic and hydraulic calculatins necessary t determine the impact f hydrgraph timing mdificatins f the prpsed land-disturbing activity, with and withut the detentin structure (results f analysis will determine the need t mdify the detentin design r eliminate the detentin requirement see nte 2 belw) Inputs and utputs frm analysis prgram Summary table f the peak inflws, peak utflws, discharge velcities, and maximum water surface elevatins (WSE) fr the 2, 10, 25 and 100-year, 24-hur strm events fr each detentin structure Stage-strage-discharge relatinship fr the utlet structure f each detentin structure Nte: SEDCAD Users, please refer t SEDCAD mem: Nte: The Cunty will determine the verall area f analysis during the pre-design meeting. An example wuld be using the 10% rule in perfrming analysis. The hydrlgic analysis shuld be cnducted fr the larger drainage area, where the site in questin encmpasses 10% f the ttal drainage area. Fr example, if yur site is 10 acres, then the hydrlgic analysis shuld be perfrmed at a pint dwnstream where the cntributing drainage area, including yur drainage area, is apprximately 100 acres. Nte: The curve number fr pen water, marshes, retentin / detentin areas, etc. shuld be 98 t 100 Design Design calculatins fr structures and strm drainage system The Cnstructin Detail f utlet cntrl structure and crss-sectin f the dam/berm, including elevatins and dimensins must crrespnd t the calculatins, stage-strage vlumes and elevatins fr the Water Quality, and fr Water Quantity fr the 2, 10, 25, and 100-year strm events. Orifice cnstructability shuld be cnsidered (d nt specify rifice diameters with increments f less than 1/4") Maximum WSE fr the 25-year strm event belw the emergency spillway with 0.5-ft f freebard between maximum WSE fr the 25-year strm and the emergency spillway Freebard criteria is the same fr all required strm events. Maximum WSE fr the 100-year strm event belw the embankment with 1-ft f freebard between maximum WSE fr the 100-year strm and the embankment Freebard criteria is the same fr all required strm events. Dewatering time calculatins fr the 25-year strm event (dry pnds must drain cmpletely within 72 hurs) Prvide a flat maintenance shelf/berm with a minimum width f 10-ft arund the perimeter f the basin. The pnd berm must prvide lad bearing capability fr industrial maintenance mwers. Nte: Small rifices (thse less than 3 ) are prne t clgging Nte: All water cntrl dams must meet dam safety requirements Fr Multi-purpse basins (basins that will be used during cnstructin fr sediment cntrl and fr bth pst cnstructin water quality and quantity cntrl): Utilize ne permanent riser and utlet barrel cnfiguratin fr bth phases f the prject that is based n pst-cnstructin water quality and quantity cntrl. Design the riser t have a Flating Skimmer attached t the bttm f the riser (typically the pst cnstructin water quality lw flw rifice) during the cnstructin phase f the prject t dewater in a time perid ranging between 24 t 72 hurs. Design the riser with rifices/weirs t prvide peak flw rate cntrl reductin. Prvide calculatins r design aids shwing that the basin will prvide calculatins shwing that the basin is designed t meet pre-cnstructin peak flw rates fr the 2-year, 10-year, and 25-year strm events. (50-year fr Gilder Creek Watershed; 100- year fr City f Mauldin) as well as meet a minimum 80% trapping efficiency fr sedimentlgy. Design a stabilized Emergency Spillway that safely passes the 100-year 24-hr strm event with a minimum ne-ft f freebard frm the 100-year 24-hur water surface elevatin t the tp f the dam. Prvide a Frebay area. Pst Cnstructin Water Quality 13. PERMANENT WATER QUALITY REQUIREMENTS Permanent water quality addressed (all prjects that disturb 1 acre r increase flw > f 1 cfs). The preferred methd is t size permanent water quality capture devices t trap 85% f ttal suspended slids based n annual ladings by particle class. An alternative as a default criteria, a device may be sized t capture the first inch f runff frm the impervius area f the site and discharge it ver a twenty-fur (24) hur perid. Fr site that discharge int Impaired Waterbdies, use IDEAL mdel t run the water quality benefits f the chsen design fr pre-develped and pst-develped pllutant lad (array f pllutant remval and/r impact). All input data must be supplied. 85% TSS trapping efficiency calculatins with mst current IDEAL Mdel has met Greenville Cunty permanent Water Quality requirements. If using the default criteria (first inch f runff), prvide hand calculatins fr the first flush vlume and rifice calculatins. When sizing the rifice nly runding dwn is permissible. Page 5 f 11 Revised: August 2016

6 Infiltratin Practices designed t accept, at a minimum, the first 1 f runff frm all impervius areas and designed in accrdance with Greenville Cunty Infiltratin Plicy Fr areas nt draining t a pnd r infiltratin practice, shw hw permanent water quality requirements were addressed Water quality rifices shuld be a size that is cnducive t prper peratin and maintenance. Orifices less than 3 in diameter are prne t clgging Waters f the U.S./State are nt used fr permanent water quality cntrl (alternative means f treatment must be used if an existing pnd is t be used fr water quantity cntrl) Nte: Cmmercial and Industrial flr drains shall nt be cnnected t strm drainage system withut apprved pre-treatment. Nte: Other nn-traditinal strmwater cntrls such as Biretentin areas, cnstructed wetlands, etc. may be used. See the Greenville Cunty Strmwater Design Manual fr infrmatin. Nte: Pre-fabricated r prprietary treatment devices are apprved n a case-by-case basis if adequate remval efficiency can be demnstrated. Prvide pllutant remval efficiency data, apprved by EPP ETV's r NJCAT s prgram. Type f system selected shuld be based n the ability t remve the pllutants f cncern in that area/situatin (bacteria, hydrcarbns, etc.). Hydraulics 14. CONVEYANCE MEASURES AND STABLE CHANNEL All channels and diversin ditches able t handle the 25-year strm event with nn-ersive velcities f less than 5 feet per secnd during cnstructin (use apprpriate CN fr disturbed areas) and pst-cnstructin (if velcity exceeds 5 ft/s, then permanent measures t reduce the velcity t a nn-ersive rate must be prvided) Fr all prtins f the drainage system which are expected t carry ver 50 cubic feet per secnd (cfs) fr the 100-year strm, the 100-year plus ne ft fld elevatin analysis shall be required if ne f the fllwing criteria apply: Prvide hydrlgy and hydraulic data and infrmatin t shw hw strmwater will be safely cnveyed fr the 100 year strm event. ( All municipalities included) The estimated runff wuld create a hazard fr adjacent prperty r residents The fld limits wuld be f such magnitude that adjacent residents shuld be infrmed f these limits. Fr all prtins f the drainage system which are expected t carry 150 cfs r mre fr the 100-year strm, the 100-year plus ne ft fld elevatin analysis shall be dne and fld limits shall be shwn n the drainage plans. Drainage Maps shwing areas draining t designed channels, structures, strm drainage systems, catch basins (if subdivisin with rad drainage system) Design calculatins f planned channel, crss sectin and methds t stabilize Design calculatins fr structures and strm drainage system Design calculatins, crss sectins and methds f stabilizatin f existing and planned channels. Design calculatins input and utput data sheets fr subdivisin radway catch basin drainage system (if cmb review) 15. ENERGY DISSIPATERS/OUTLET PROTECTION All utlets stabilized with apprpriately sized riprap aprn r ther structure (prvide calculatins) Design calculatins f energy dissipaters belw culverts and strm sewer utlets All channelized flws in a stable cnveyance and energy dissipated prir t entering surface waters Nte that apprpriate utlet prtectin and energy dissipatin is als required fr pst-cnstructin Site Plan Requirements 16. GENERAL SITE PLAN FEATURES: Lcatin map with site utlined n first plan sheet (map shuld have enugh detail t identify Surface Waters f the State within 1 mile f the site) Legend Streams, lakes, pnds, drainage ways, dams, wetlands, fld ways, and 100 year fldplain limits. Prpsed imprvements n the site (including any future develpment planned) Planned and existing building's lcatin and elevatin. Planned and existing rad's lcatin and elevatin. Existing and planned drainage patterns (including ff-site areas that drain thrugh prject) Existing and prpsed easements. Prperty lines and adjacent landwners' names Existing and prpsed cnturs fr entire disturbed area Limits f disturbed area Page 6 f 11 Revised: August 2016

7 Lcatins f ff-site material, waste, brrw, r cnstructin equipment strage areas, excluding rll-ff cntainers (Nte: Hauling waste sil ffsite may nly g t a permitted site. Sme ff-site disturbed areas may require a separate applicatin fr NPDES cverage) Lcatin f Cncrete Washut and ther Pllutin Preventin Measures Lcatin and identificatin f any strmwater discharges assciated with industrial activity (nt cnstructin) Delineatin f WS, including wetlands (see checklist item18) and blue line streams. Rad prfiles with existing and prpsed grund elevatins (if n cnturs are shwn n the plans) Cnstructin details with installatin and maintenance requirements fr temprary and permanent BMPs/structures and strm drainage system Lcatin f temprary and permanent BMPs/structures Use Greenville Cunty specificatins and details n plans. If N Greenville Cunty specificatin available use SCDHEC Standard ntes see current SCDHEC Design Checklist Registered engineer s signed and dated seal Engineering Firm s Certificate f Authrizatin seal If the SWPPP has been develped by a Registered Prfessinal Engineer, Registered Landscape Architect r Tier B Land Surveyr, the fllwing statement must be included n the site plans: I have placed my signature and seal n the design dcuments submitted signifying that I accept respnsibility fr the design f the system. Further, I certify t the best f my knwledge and belief that the design is cnsistent with the requirements f Title 48, Chapter 14 f the Cde f Laws f SC, 1976 as amended, pursuant t regulatin et seq. (if applicable), and in accrdance with the terms and cnditins f SCR NAVIGABLE WATERS Extra plan sheet shwing impacts t navigable water and descriptin f activity included if S.C. Navigable Waters (SCNW) crssing and separate SCNW permit has nt been btained fr all activities Nte: Fr NOl s initially submitted t delegated entities, if prject has SCNW crssing and if separate SCNW permit has nt been btained fr this crssing, then this item will be reviewed by S.C. DHEC befre NPDES cverage will be granted 18. WATERS OF THE STATE, INCLUDING WETLANDS Delineatin f all waters f the State (WS), including wetlands, shwn and labeled n plans (delineatin nt required if a 100- ft undisturbed buffer can be maintained between the WS and all land-disturbing activities) Additinal, separate plan sheet that shws all WS n the site and the impacted areas with a descriptin f the activity(s), whether it is permanent r temprary, and any ther relevant infrmatin If impacts t WS, utlined areas f impacts and labeled that n wrk can begin in this area until all necessary USACOE permits and SCDHEC 401 certificatins have been btained. Nte: It is recmmended that a minimum 20-ft buffer between a sediment trap/basin and WS be used. 19. STORMWATER MANAGEMENT FACILTIY Cnstructin details fr facilities, structures and strm drainage system Bttm f all detentin and retentin pnds graded t have a slpe f nt less than 2%. Cunty requires the riser t have a designed trash rack and anti-vrtex device. Permanent maintenance access t all permanent detentin structures (easements may be needed fr structures surrunded by lts) Prvide a detail f utlet structure and crss-sectin f the dam/berm r pnd bank, including elevatins and dimensin that crrespnds t the calculatins, stage-strage vlumes and elevatins fr the Water Quality, 2-, 10-, 25-, and 100-year strms Nte: Emergency spillways shuld nt be built n fill slpes Nte: The Cunty recmmends a maximum slpe f 3: 1 n pnd embankments t allw fr ease f maintenance. Dry Detentin Pnds that pnd water ver 2 feet deep and have side slpes steeper than 3:1 must have a 4 ft safety fence. Nte: The Cunty requires phase sequence and verificatin fr all permanent BMP s. 20. PHASED SEDIMENT & EROSION CONTROL PLANS Phased Sediment and Ersin Cntrl Plans are nt required when land-disturbance is 5 acres r less Fr land-disturbance between 5 and 10 acres, a tw-phased strmwater management and sediment and ersin cntrl plan is required fr all nn-linear prjects. Each phase must be shwn n a separate plan sheet. Plans shuld address the transitin between phases. Page 7 f 11 Revised: August 2016

8 Phase 1 Initial Land Disturbance Must include perimeter sediment and ersin cntrl BMPs required prir t initial/ mass clearing and ther apprpriate BMPs needed t maintain cmpliance with the permit. On sme sites, this may include apprpriate BMPs fr demlitin f existing structures Phase 2 Stabilizatin - Sediment and ersin cntrl BMPs required during the remainder f grading and cnstructin. Must als include apprpriate BMPs fr stabilizatin grassing, inlet prtectin, etc. Fr land-disturbance greater than 10 acres, a three-phased strmwater management and sediment and ersin cntrl plan is required fr all nn-linear prjects. Each phase must be shwn n a separate plan sheet. Plans shuld address the transitin between phases. Phase 1 Initial Land Disturbance Must include perimeter sediment and ersin cntrl BMPs required prir t initial/ mass clearing and ther apprpriate BMPs needed t maintain cmpliance with the permit. On sme sites, this may include apprpriate BMPs fr demlitin f existing structures Phase 2 Cnstructin - Sediment and ersin cntrl BMPs required during the majrity f grading and cnstructin activities. Phase 3 Stabilizatin - Sediment and ersin cntrl BMPs required near the cmpletin f the cnstructin prject. Must als include apprpriate BMPs fr stabilizatin grassing, inlet prtectin, etc. If the pnd is t be used fr sediment cntrl during cnstructin, temprary hrseshe-shaped riprap berm in frnt f any lw level utlets prvided during cnstructin and shwn n the pnd detail Lw Impact Develpment measure, biretentin cells, infiltratin, and ther pst-cnstructin practices shuld be installed nly after the drainage area t these practices has been stabilized Clean-ut stake, marked at ½ the designed sediment strage depth, prvided in all sediment basins/sediment traps Rck check dams prvided in temprary diversins Installatin detail fr ersin cntrl blanket (ECB) r turf reinfrcement matting (TRM) if ECBs r TRMs t be used Stabilizatin f cnveyance channels is t be cmpleted within 7 days f channel cnstructin Temprary cnveyance channels shuld be utilized t divert cncentrated strmwater flws frm running nt and within the disturbed area Prvide a minimum f 3 rws f Baffles in the basin. At least ne rw f Baffles will be placed between the riser structure and all pipes r channels discharging t the Basin. Nte: A detentin facility which has been certified and accepted fr pst cnstructin water quality cannt be used fr sedimentlgy fr subsequent phases f wrk Nte: The Cunty requires phase sequence and verificatin fr all strmwater features BUFFERS Prvide and maintain a minimum f 45 buffer when surface waters are lcated n r immediately adjacent t the cnstructin site Duble rw f silt fence prvided in all areas where 50 undisturbed buffer cannt be maintained between the disturbed area and surface waters Minimum f 10 maintenance buffer prvided between the last rw f silt fence and the surface waters, r, if buffer nt prvided, then statement frm P.E. n plans indicating hw silt fence will be installed and maintained withut impacts t surface waters All channelized flws in a stable cnveyance and energy dissipated prir t entering surface waters Clearly mark/delineate with flags, tape, r similar marking device, the buffer area t ensure buffer areas visible Lcatin f any buffers r prtected strand f trees (as identified in the Tree Prtectin Plan if applicable) Nte: The buffer area can nt be used t treat sediment laden strmwater 22. SLOPES AND/OR EMBANKMENTS All slpes must be stabilized Divert cncentrated flws arund steep slpes using slpe drains r temprary diversins. Slpe drains designed in accrdance with the Greenville Cunty Strmwater Design Manual Slpe drains prvided where cncentrated flws discharge nt a fill slpe and nt steep slpes Fr all slpes steeper than 1.5:1, identificatin f stabilizatin practice (e.g., ECB, TRM) Minimize Disturbance t Steep Slpes (3H:1V) r greater Utilize apprpriate measures t prevent ersin (ersin cntrl blankets, surface rughening, terracing, etc.) Nte: Measures, in additin t grassing r hydr-seeding, include synthetic r vegetative matting, diversin berms, temprary slpe drains, etc. Page 8 f 11 Revised: August 2016

9 Nte: If retaining walls r fill slpes are t be cnstructed at the dwnstream prperty line, the Cunty recmmends a 10 buffer t allw fr cnstructin and maintenance. If a 10' buffer is nt prvided, then prvide permissin frm the adjacent prperty wner fr pssible land-disturbing activities n his prperty 23. UTILITY LINES Limits f disturbance include areas necessary fr installatin f all utilities (cable, electrical, natural gas, water and sewer), as apprpriate Fr instances where the lcatin f cable, electric, and natural gas has nt been determined at the time the SWPPP is develped, SWPPP preparer may include a nte that the installatin f these is t be within the permitted limits f disturbance and that installatin utside f these areas will require a mdificatin t the permit Inlet prtectin prvided at all existing inlets that receive flws frm the disturbed areas; als add this as a nte n the plans Fr all utility lines crssing WS, narrative and detail shwing sediment and ersin cntrl measures prvided n plans Nte fr cnstructin entrances t be prvided at all lcatins where cnstructin traffic accesses a paved radway 24. INLET PROTECTION Prvided at all inlets (existing and prpsed) Hay bales cannt be used Steel psts and buried fabric shwn fr filter fabric inlet prtectin Inlet prtectin details prvided fr pre-paving and after radways have been paved Nte: The Cunty recmmends that an inlet nt have mre than ne (1) acre draining t it. 25. DISCHARGE POINTS Strm drainage r pnd utfalls carried t an existing drainage utfall such as a pipe, ditch, etc. N new pint discharges nt adjacent prperty where there was nt a pint discharge previusly, unless written permissin frm the adjacent prperty wner is prvided Level spreaders, plunge pls, etc. prvided when the prpsed utlet is near the prperty line and nt directed t an existing utfall, such as a creek r ditch Twenty (20)-ft minimum buffer and level spreader is prvided between the prperty line and the discharge pint. Outlets shall nt discharge n fill slpes Riprap detail shws aprn dimensins and stne sizes fr each pad r each pipe diameter Filter fabric installed beneath all riprap Cnstructin details f energy dissipaters belw culverts and strm sewer utlets 26. VEGETATIVE STABILIZATION Phasing plan fr stabilizatin Areas and acreage t be vegetatively stabilized Planned vegetatin with details f plans, seed, mulch and fertilizer Greenville Cunty Specificatins fr permanent and temprary vegetatin Greenville Cunty grassing and stabilizatin specificatins (temprary and permanent) included n plan. Greenville Cunty Specificatin fr seeding mixes and rates, type f sd, seedbed preparatin, time and fertilizer applicatins Greenville Cunty Mulching and related data Tree Prtectin/Planting Plan (will frward t the Zning department fr review) 27. CONSTRUCTION SEQUENCE Cnstructin Sequence shuld accurately reflect the nature and timing f cnstructin activities fr the site Schedule and sequence f cnstructin peratins (identify all phasing). Lcatin f temprary sediment cntrl and sequencing if phased Cnstructin sequence related t sediment and ersin cntrl (included installatin f critical measures prir t initiatin) f the land disturbing activity and remval f measures after areas are stabilized. Sequence shuld begin with the installatin f perimeter cntrls and end with the remval f sediment and ersin cntrl measures nce the site has been finally stabilized Cnstructin sequence (implementatin f all strmwater and sediment cntrls in the first phase f cnstructin; ensure that basins, traps, pnds, etc. can be installed befre the area draining t them is cleared and grubbed) Page 9 f 11 Revised: August 2016

10 Engineer certificatin fr all permanent BMP s fr vlume, tpgraphy and dimensins Address cnversin f any temprary sediment cntrl structures t permanent measures (i.e., cnversin f a sediment basin t a permanent detentin basin) Sequence shuld reflect implementatin and transitin between each phased plan (see Sectin 20 ) Cnstructin Sequence shuld include the fllwing line items: Maintain all sediment and ersin cntrl features thrughut the life f the prject Inspectins t be every 7 calendar days and within 24 hurs after each rainfall event that prduces1/2-inches r mre f precipitatin Cnstructin sequence bar chart with applicable time units. Other Agency Cmpliance Requirements 28. USACOE s Jurisdictinal Determinatin (if applicable) 308. USACE s Sectin 404 Permits (if applicable) Prvide a cpy f the permit applicatin and apprval letter. 29. SCDHEC 401 Water Quality Certificatin (if Applicable) Nte: If there are prpsed impacts t WS, then it is advised that yu cntact USACOE ( ) and/ r S.C. DHEC Water Quality Certificatin, Standards & Wetlands Prgrams Sectin ( ) t determine additinal requirements befre submitting the Ntice f Intent (NOI). Nte: If WS are t be impacted, wrk cannt be perfrmed in these designated areas until all necessary permits have been acquired. Nte: If a USACOE permit is required fr cnstructin f r access t a temprary r permanent strmwater management structure, NPDES permit cverage cannt be granted until the USACOE permits and S.C. DHEC 401 Sectin certificatins are btained. 30. SCDHEC CGP Requirements Current SC DHEC NOI Applicatin - cmpleted in its entirety. Pre-Cnstructin Cnferences Inspectin Requirements, Inspectin Lgs & Reprts Maintenance Plices & Reprts Recrd Keeping Requirements, Rainfall Recrds, Additinal Site Lgs and Reprts Nte: If wrk will be perfrmed within a designated fldplain required certificatin and permits will be required fr the Fldplain Manager prir t apprval f the Land Disturbance Permit Acceptance and Maintenance 31. AS-BUlLT DOCUMENTS Prvided fr all previusly apprved detentin pnds that will receive flws frm new drainage/cnstructin areas As Built Surveys f Strm Water Facilities (Quantity and Quality) prepared by a Suth Carlina Licensed Land Surveyr Grades/cnturs/depths fr pnd Elevatins and dimensins f all utlet structures, including: Pipe and rifice inverts and diameters Weir elevatins and dimensins Riser dimensins and elevatins Emergency spillway dimensins and elevatins Lcatins and inverts fr all pipes discharging int the pnd If the elevatins r dimensins f the structures listed abve d nt match thse used in the apprved plans, certificatin statement signed by the prject's Registered Engineer indicating that the pnd, as built, will functin within all applicable standards prvided [new analysis f the pnd (ruting) may be necessary] Nte: As-built survey and/r analysis fr Cmmercial Sites must be submitted and accepted by the Cunty befre Ntice f Terminatin (NOT) is submitted r at 50% build-ut in Residential Subdivisins. Page 10 f 11 Revised: August 2016

11 32. PERMANENT STORMWATER MANAGEMENT STRUCTURE MAINTENANCE Signed Strmwater Management Facility Maintenance Agreement frm the respnsible party accepting wnership and maintenance f the structure(s) Descriptin f maintenance plan fr each type f feature (t be used in restrictive cvenants) See Greenville Cunty HOA/POA Restrictive Cvenant Language Dcument Schedule f maintenance prcedures Example f Typical maintenance items t be addressed fr a pnd: Grass t be mwed Trees t be remved frm within the pnd and n the embankment Trash and sediment t be remved frm inside f and arund the pnd utlet structure Orifices t be cleaned and unclgged Outlet pipe t be cleaned, inspected, and repaired Sediment accumulatin t be remved frm pnd Pnd bttm t be regraded t prvide prper drainage twards the utlet discharge pint Energy dissipater t be cleaned and repaired Emergency spillway, if applicable, t be inspected and repaired Ersin n side slpes, if present, t be addressed The Cunty must be ntified in writing f any changes in maintenance respnsibility fr the strmwater devices at the site (include this statement in agreement). Detailed r manufacturer-specific maintenance items fr prprietary cntrl devices (il-water separatrs, etc.), undergrund detentin structures, exfiltratin systems and nn-traditinal strmwater cntrls (cnstructed wetlands, biretentin, etc.) in reprt and n plans with mdel numbers. (Can be used fr cmmercial/industrial sites nly; prhibited in residential subdivisins.) The fllwing language must be present as a nte n bth the final plat (if applicable) AND all sets f the strm water plans: As wners f prperty which is designed t drain t a particular strm water management facility in any phase f develpment in Subdivisin, each prperty wner shall be equally respnsible fr inspectin, maintenance, and repair f that strm water management facility t which their lt is designed t drain in Subdivisin, as shwn / fund n the apprved strm water plan fr Subdivisin and / r recrded strm water management facility maintenance agreement Instrument #_, Dated _. This is in the absence f a Hmewner s r Prperty Owner s Assciatin. Nte: If the entity r persn with maintenance respnsibility changes, then a new maintenance agreement, signed by the new persn respnsible fr maintenance, must be prvided t the Cunty at clseut r at 50% build-ut. If a new, signed maintenance agreement is nt prvided t the Cunty, then the entity/persn wh signed the mst recent maintenance agreement n file with the Cunty may be cnsidered the respnsible entity. Nte: SEDCAD users please refer t the mem regarding the input f utlet structures, design calculatins fr structures, and strm drainage system Nte: Maintenance requirements fr each BMP shuld be listed n the detail I, as the SWPPP Preparer, understand and have read all the instructins and selected the applicable items and have included all the infrmatin requested fr this Plan Submittal Package. Printed Name f SWPPP Preparer Signature f SWPPP Preparer Date Please check the apprpriate persn: Engineer Tier B Land Surveyr Landscape Architect * NOTES: Plan submittal s that are received after 2:00 p.m., will be lgged in fr the next business day. The Prvisins f all required infrmatin is nt a guarantee f apprval. The apprving authrity may reasnably require supplemental reprts, data and additinal infrmatin. Standard review times may nt apply if additinal staff research time is necessary in the review f innvative design alternatives. Cunty staff will prvide a status reprt regarding review prgress at the 10 business day perid. Fr Plan Submittal inquires, please call the Permit Page 11 f 11 Revised: August 2016