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LAND DEVELOPMENT DIVISION ENGINEER FORUM

LAND DEVELOPMENT DIVISION ENGINEER FORUM. February 23, 2012 Conference Room D. Today’s Agenda. 2009 SCDHEC’s Audit Findings 2010 Woolpert’s Internal Audit Findings Results from Summer 2011 Survey Proposed Changes EPA and SCDHEC Regulation Forecast

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LAND DEVELOPMENT DIVISION ENGINEER FORUM

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  1. LAND DEVELOPMENT DIVISIONENGINEER FORUM February 23, 2012 Conference Room D

  2. Today’s Agenda • 2009 SCDHEC’s Audit Findings • 2010 Woolpert’s Internal Audit Findings • Results from Summer 2011 Survey • Proposed Changes • EPA and SCDHEC Regulation Forecast • Status and expected contents of our next NPDES MS4 permit

  3. Land Development Regulations • Land Development Regulations Update • Stakeholder Approach • Time Frame – Begin March 2012 & up to 1 year to complete stakeholder review • Includes LID’s, TND’s, Centers & Corridors, Traffic Impact, etc. • Update Zoning Ordinance to reflect changes in LDR

  4. SCDHEC’s Audit Results • EPA guidance requires SCDHEC to conduct an in-depth audit at least once every five (5) years • In March of 2009 SCDHEC held a two day audit covering all 13 elements of our MS4 Permit • The conclusion was Greenville County’s program was satisfactory with deficiencies in two elements: • Construction Site Runoff • Public Education and Public Participation

  5. DHEC’s Audit Comments • …” The County needs to improve documentation of how they are determining that BMP’s proposed on sites that drain to Impaired Waters (both 303(d) listed and those included in a TMDL) are adequate to address the pollutant of concern in the receiving water body.” • “Overall, Greenville County is not effectively approving construction site plans to MEP standards. The MS4’s focus must be on water quality.”

  6. SCDHEC Audit Comments • Silver Meadows Phase III: SCR10I232 • 1. Greenville County application form says 25 disturbed acres; NOI says 23.9 disturbed acres • 2. One engineer signed and sealed Greenville County application and different engineer signed and sealed plans and NOI • 3. NOI indicates impacts to 121' stream-not mentioned or shown on plans; the area of impacts should be clearly identified and shown on the plans • 4. No wetlands/ waters of the State delineation on plans-impacts to wetlands/ waters of the State cannot be assessed/ reviewed if the delineation is not shown on the plans. Surveyed delineation must be shown on the plans; plans must be reviewed to ensure that appropriate BMPs are provided to prevent sediment from washing into wetlands/ waters of the State and to ensure that basins/ traps/ any structures shown in the SWPPP are not being constructed in wetlands/ waters of the State without appropriate Corps' 404 permit and SCDHEC 401 certification. See Section 2.1C of SCR100000. If the entire SWPPP cannot be implemented and a 404 permit is needed for the associated impacts to wetlands/ waters of the State, then NPDES coverage cannot be issued until 404 permit has been issued and is effective (SC DHEC 401 certification of the 404 permit must be issued for 404 permit to be issued and effective).

  7. 5. Pre- and post-development drainage area maps and during construction drainage area map that clearly correspond to the calculations not provided-these maps must be provided to ensure that at least the entire analyzed in pre-development " calculations is analyzed in the post-development calculations and to check that the area modeled as draining to a structure actually drains to that structure. According to the provided calculations, 1.21 acres less area was analyzed in the post­development calculations-that is not acceptable. Post-development flows must be less than pre-development flows at all discharge points. The same or a greater area must be analyzed for the post-development calculations for an accurate comparison. • Several inconsistencies between plans, details, and calculations for pond 1: Top of pond elevation, top of riser elevation, emergency spillway width, orifice sizes and elevations. The inconsistencies in the top of riser elevation are a major problem because the top of the riser on the detail is 903'. In the calculations, the top is at 907.5'. The 10-year water surface elevation in the calculations is 904.6', so flows would be going through the top of the riser, if constructed using the elevation listed on the detail, which could mean the peak 10-year flows are greater than the pre-development flows and regulatory requirements may not be met. Many of the elevations and dimensions used in the IDEAL model calculations are different from those on the plans and details and in Sedcad calculations. Also, in the IDEAL model, the drainage area for the pond was listed as 34 acres; however, in the Sedcad calculations, the drainage area for the pond was 53 acres. • On the pond 1 detail and chart, the same orifice elevations are listed as being the invert and centerline elevations. For example, on the detail, 2-10" orifices are listed at 905', invert elevation. However, on the chart, 2-10" orifices are listed at 905', centerline elevation. The calculations would not be able to be reviewed without knowing whether the elevations are invert or centerline. The Sedcad calculations would then need to be reviewed to ensure that the orifices were entered using their centerline elevation, according to the Sedcad memo on our website.

  8. 8. Sedcad calculations were not reviewed in accordance with Sedcad memo posted on our website. Orifices with diameters greater than 3" were modeled in Sedcad. 9. For pond 1, the water quality volume was listed as 2.478 ac-ft on the detail. However, the water quality volume is 4.42 ac-ft. Also, Sedcad cannot be used for the water quality calculations because flows are still coming into the pond. The water quality calculations are for a brimful drawdown-the entire water quality volume must be in the pond at one time and then released over at least 24 hours, with no flows coming into the pond during the release. Also, need water quality drainage area map that shows the areas that should drain to each pond. In the water quality calculations for pond 2, the elevations and orifice size used in the calculations does not correspond to the plans (bottom at 882' on plans, 956' in calculations; top at 886' on plans, 972' in calculations; 2" orifice on plans, 2.5" orifice in calculations). Also, the calculations do not show that the volume is released over at least 24 hours. In 24 hours, more than the water quality volume has drained out, which means the water quality volume drained out in less than 24 hours. For pond 3, it does not appear that the water quality volume is contained within the water quality basin. Also, the elevations on the plans do not correspond to the elevations in the calculations. 10. Water quality ponds should have been included in post-development calculations , because some detention is provided and timing effects should have been reviewed because of existing flooding problems. 11. No limits of disturbance on plans (23.9 disturbed acres, 75 total acres) 12. No proposed contours shown for lots and no note regarding assumed disturbed area per lot-proposed contours should be shown for all areas within limits of disturbance, except individual lot disturbance with no mass grading 13. Ponds and swales to divert flows to the ponds should be in easements or common areas-this does not appear to be true for the flows from lots 38-51

  9. 14. Are ponds to be used as sediment basins during construction? That is not clear from the plans, but the construction sequence mentions that sediment ponds and traps and diversions to them are to be installed. Sediment calculations were provided for a big basin and smaller drainage areas through silt fence. The calculations for the smaller areas that were modeled through silt fence do not appear to be accurate after the storm drain system is installed. The flows through the storm drain system will not sheet flow to the silt fence as modeled. • 15. Construction sequence not in correct order-basins and traps and diversions to them must be installed before clearing, grubbing, and grading activities, except the clearing and grubbing in the area of the basins, traps, and diversions. Also, General Note 3 on sheet SW-4 states that diversions and traps are to be provided beginning with grading. Traps and diversion should be provided before clearing and grubbing-note should be amended. Also, Implementation note 1 states that erosion control measures begin with grading-note should be amended to require sediment and erosion control measures before clearing and grubbing. • 16. Water quality ponds not shown on Erosion Control plan, SW-2. Construction sequence does not specify when they are to be installed, if they are not to be used during construction. • 17. Check dams needed in all temporary diversions; temporary diversions to the sediment basin and traps, if any will be used as mentioned in construction sequence, must be shown on the plans. • During construction outlet from line I appears to drain to silt fence. Silt fence should not be used in areas of concentrated flows. A more substantial structure is needed at this outlet during construction.

  10. 19. Sediment trap detail: No cleanout information listed, sizing criteria (3600 ft3/ acre) not provided on detail, no maximum drainage area listed on detail (maximum of 5 total acres). No trap labeled or shown on plans, but sediment trap sizing calculations provided for 12.1 acres. Trap cannot be used for 12.1 acres. 20. Inlet protection: Sediment tube inlet protection detail was the only inlet protection detail provided, and it is only for pre-paving. The plans call for fabric drop inlet protection, but no detail provided on plans. 21. Lot detail: double row of silt fence to protect wetlands/ waters of the State where 50' undisturbed buffer cannot be maintained 22. Riprap sediment dike-no detail provided but called for on plans 23. Sediment check detail-no detail provided but called for on plans 24. Sheet SW-4, General note 8 should be omitted-the sediment and erosion control measures shown on the plans are not just recommendations; the measures must be implemented as shown on the plans. Or, the note could be amended to explain allowable minor modifications and the process for major modifications (involving calculations, etc.). 25. Note on sheet SW-1 about riprap pad at outlet into pond 1 refers to sheet 8 for table. Sheet 8 was not provided. 26. Energy dissipator: note at outlet in pond 3 on sheet SW-1 refers to sheet 7 for energy dissipator. Sheet 7 not provided. 27. Old stabilization note, bottom left-hand corner of sheet SW-4, note 3

  11. Springs at Greenville Apartments: SCR10K471 1. Pond maintenance plan and Flogard Plus maintenance plan not provided 2. On page 4 of the report, the consultant indicated that the site development will not contribute to the BIO impairment or fecal impairment (TMDL). That is not acceptable. BIO is an impairment that is expected to be affected by construction stormwater discharges, unless the consultant can justify how sediment will not be contained in the construction stormwater discharges. 3. The pre- and post-development analysis cannot be fully reviewed because the analysis points are different according to the pre- and post-development drainage area maps. The same analysis points should be used for pre- and post­development calculations; also, the analysis points should be the points where flows leave the site/ property. For example, the analysis point for pre­development area 2 should have been an analysis point in the post-development condition because flows continue to leave the property at this point in the post­development condition. However, the analysis point for this side of the property was moved and now includes the undetained portions of the site, some of which flow directly to the creek and not onto the adjacent property. Also, the entire area included in pre-development area 2 does not drain to the analysis point shown on the drainage area map; part of the area sheet flows to the adjacent property. Therefore, the analysis is not accurate. 4. According to the plans, sediment trap 1 is shown at the end of the outlet pipe from basin 1 and trap 2 is shown in basin 1 at the end of a pipe/ temporary diversion ditch-maximum drainage area for a trap is 5 acres, which it appears was exceeded for traps 1 and 2. Sediment trap sizing calculations and trapping efficiency calculations were not included in the report. Drainage area map that shows the maximum drainage area for each sediment trap and basin, throughout the life of the construction project not provided. Sediment trap symbols associated with check dams shown along the temporary diversion ditch that empties into basin 1/ trap 2. Each of those sediment traps must be designed to account for the entire area that drains into it, not just the direct area. Sediment trap sizing calculations should have been provided for all sediment traps.

  12. 5. Sedcad calculations for pond 1: only 12.24 acres were routed through the pond; according to the post-development drainage area maps, 14.43 acres drains to pond l. Revised calculations are needed. Also, the 25-year storm overtops the emergency spillway; the 10-year storm event must be contained below the spillway. This could not be reviewed because 10-year storm event calculations were not provided. • 6. Hydraflow calculations for basin 1: emergency spillway/weir B goes from 913' to the top of the pond; however, according to the plans, the weir is a 6" slot to an 18" pipe. It does not appear that the structure is accurately modeled because the actual capacity appears to be limited to less than what is modeled in Hydraflow. • 7. If pond 1 will be a wet pond, then the curve number should be 98. However, according to the post-development curve number map, the curve number used for it was 61. Need amended curve number and post-development calculations. • 8. First flush calculations for pond 2: surface area used in the calculations does not correspond to the surface area in Hydraflow or on the chart-orifice appears to be too large and will release the first flush volume in less than 24 hours. Revised first flush and post-development routing calculations needed. • 9. IDEAL model calculations: dimensions and elevations used in the calculations do not correspond to plans and details (outlet pipe diameter for pond 1, separate weir for pond 2, etc.) 10. Because of the complexity of the plans, phased grading plans needed. The initial phase would show the grading necessary to install the basins and traps and diversions to those structures, along with the perimeter sediment and erosion control measures. • Limits of disturbance shown through the western wetlands area • No sediment and erosion control measures shown on sheet C-202-appears that the silt fence, inlet protection, check dams, sediment traps, etc. layers are not shown because those features are shown on sheet C-201 in the area on either side of the matchline on sheets C-201 and 202.

  13. 13. Need permission from the adjacent property owner, McGinnis, to build retaining wall on the property line, or show how the wall will be able to be constructed on the property line without access to the lower side of the wall. 14. Hatched area to the east of basin 2 and the proposed sewer line, parallel to the road-label for this area cut off 15. No sediment and erosion control measures provided for the area of installation of the outlet pipe for basin 2, which is shown as being installed up to the edge of the creek 16. Outlet protection not provided for the pipe under the emergency entrance 17. Installation of temporary diversions to the sediment basins and installation of the sediment traps not included in the construction sequence-diversions must be installed as soon as the basins are completed before the site is cleared or grubbed. Check dams should be installed in all temporary diversions. 18. On the plans, the label for the riprap protection for the stream crossing area refers to the detail-did not see where a detail of this area was included. A stream crossing detail showing sediment and erosion control measures that will be used to prevent sediment from entering the wetlands/ waters of the State should be provided. 19. Energy dissipator detail: structures 25, 50, 44, 54, 48, and 56 are listed. Energy dissipators are needed for structures 55, 57, 51, and 43 and are not listed. 20. A detail for Flogard Plus was provided. The inlets that will have Flogard Plus protection installed must be listed on the plans or details. 21. Riprap forebay-no detail provided but called for on plans 22. Permanent diversion swale-no detail provided but called for on plans 23. Check dam detail-cleanout information not listed 24. Sediment trap detail: sizing information only provided for traps 1 and 2; however, several other traps are shown on the plans 25. Riprap dike-no detail provided but called for on plans 26. Diversion ditch and diversion berm details-only detail provided for diversion swale; make sure labeled consistently on plans and details

  14. Upstate Commercial Park: SCRl0I664 • 1. As-built survey of existing ponds should have been provided before NPDES coverage issued-did not see in either permitting file; if ponds not built according to previously approved calculations, then must be modified to correspond to previously approved calculations or new post-development, water quality, dewatering calculations must be submitted to show that the pond, as built, meets regulatory requirements; if problems with original calculations, should be corrected in new as-built calculations (outlet pipes from ponds 18", but pipes under road 15") • 2. BIO impairment not addressed-see item 22 of checklist and section 3.4C.2.c; SWPPP must contain qualitative and quantitative assessment of proposed BMPs • 3. Difficult to review because not clear on plans what is existing and what land­disturbing activities are being covered under this NPDES coverage; disturbed area on NOI is 29 acres (same as disturbed area for previous NPDES coverage but appears that part of site has been developed and would not be re-disturbed). Narrative says this coverage is for lot construction; however, plans say each lot construction needs its own permit • 4. Inlet protection not shown on plans • Swales and diversions to existing basins must be in easements or common areas (from lots 1-4 to catch basin near lot 5, dike on lots 9 and 10, dike and swales on lots 12-16 and 11)-previous plans show some drainage easements for off-site flows to lots 4-6 but not shown on current plans • Construction sequence not specific far this phase-mentions clearing and grubbing for basins and installation of basins; according to plans, basins are existing

  15. Lake Conestee Nature Park Phase 2 Paved Trail: SCR10K137 1. BIO impairment not addressed-see item 22 of checklist and section 3.4C.2.c; SWPPP must contain evaluation of proposed BMPs 2. Because portions of the trail are not connected (because boardwalk areas are not included in this portion of the project), the limits of disturbance should also include areas for access to the disconnected portions of the trail-construction entrances should be provided in all locations where access is provided from a paved roadway 3. Maintenance requirements for vegetated swale not included-SWPPP mentions native plants but no specific maintenance plan provided 4. No surveyed delineation shown on plans. Areas where land-disturbing activities cannot occur until Corps' pen-nit issued must be shown and labeled on plans. Dr. Beacham's letter only mentions the absence of wetlands in the project area-the presence of waters of the State must also be determined; NPDES coverage cannot be issued until Corps' permit issued if implementation of the SWPPP is affected by the Corps' permit-implementation of the SWPPP cannot be determined unless surveyed delineation is shown on plans 5. No limits of disturbance shown on the plans 6. Double row of silt fence not provided where 50' undisturbed buffer cannot be maintained between wetlands/waters of the State and the disturbed area 7. Construction entrance-not shown on plans; must be provided; also detail must be provided 8. Outlet protection sizing information not provided-plans call for erosion control matting; calculations showing that specified ECM is adequate must be provided; culvert locations must be shown on the plans

  16. Creekwood S/D Ph II, PN SCR10J644, File No. 23-08-08-O5 l. The hydrologic analysis was not done pre- and post-development at each outfall. Pre- and post- was only done for the main basin. 2. The hydrology indicated Ponds A and G would discharge the 10-yr storm in less than 24 hours. 3. The Table of Contents given in the SWPPP bears no resemblance to the actual document. This makes it nearly impossible to follow the hydrologic analysis of this site. 4. From the hydrology, it appears the site is being delineated into smaller drainage basins to preclude the requirement for detention thru controlled outflow structures. 5. There are no as-builts for the existing on-site pond. The narrative indicates this pond is to be used as a stormwater management structure. 6. There is no signed maintenance agreement for the pond or the level spreaders. 7. The narrative states this site is to be mass-graded, then states no detention is needed due to No Significant Impact from the development of the site. 8. Permanent Water Quality is not addressed. The plan proposes using the onsite pond for "water management", but no rationale for this proposal is supplied, nor are alternative means of treatment addressed or explored. 9. Drainage area maps are inadequate/unclear. 10. Slope stabilization is not specified or detailed. 11. Limits of disturbance and proposed contour elevations are not indicated. 12. The plan is missing Standard Notes #1, 5, 9, and 10.

  17. Fork Shoals Road Self Storage,PN SCR10K224, File No. 23-08-11-08 • 1. Need to update the Standard Notes. Old version of notes are on sheet CV-2, newer version is given on sheet CV-3. • 2. There is no filter stone barrier indicated around the pond outlet structure. • Cougar Estates,. PN SCR_1OJ817 _File No. 23-08-09-03 • 1. There are numerous typos in the narrative, of a type that could cause confusion in interpreting the SWPPP. • 2. The summary table on page 5 has no column headings. • 3. Match lines on drawings do not match up from sheet to sheet. • Sheet C2.2 refers to the Detention Basin maintenance meeting the Pickens County Stormwater Regulations. The basin is in Greenville County. • The Outlet Structure detail shows a 6" orifice where the hydrologic analysis indicates a 2.5" orifice is needed. • 6. The detention basin discharges at the property line, no 20' buffer is indicated.

  18. Goodwin Farms, PN SCR10J143, File No. 23-08-05-22 l. The NOI is incorrect. Item IV.2.C.1 - the BIO impairment info is incorrectly analyzed. 2. The supporting documentation is not bound & tabbed, & therefore difficult to manage. 3. There is no legend on the plans. 4. The disturbed area is not delineated. 5. Proposed elevation contours are not shown. 6. Sedimentology is not discussed in the narrative. The Site Plan has sediment traps discharging to wet detention ponds. This design is not supported in the documentation. Maintenance of this design is not supported in the documentation. 7. Drainage Area Maps are not given for the sediment traps. 8. Sedimentology calculations use the 3 detention ponds for the calculations, but the plan indicates the detention ponds are not to be used for sediment control after the roads are built. The sedimentology of the traps is not discussed, and the drainage areas for the traps are not delineated. 9. No road profiles are supplied

  19. Assistant County Administrator’s Response • Will review its internal Plan Reviewer training requirements and make appropriate adjustments • Staff will hold joint training class with DHEC staff to get better understanding of expectations • Provide staff with in-house refresher training and incorporate the results from this audit report • Continually evaluate its construction plan review program to find improvements

  20. Impaired Water Response • In an effort to aid the design community as well as provide the County quantifiable assurances for meeting MS4 permit goals, the County has developed and made available the IDEAL computer program . With the IDEAL model, the design engineer can calculate the annual loading for the pollutant of concern for the pre-developed condition as a baseline and the developed condition showing no increase for impaired waters discharge compliance. The county intends to continue to implement the program as it is referenced in the permit.

  21. TMDL Compliance Response • The waste load allocation percent reduction from the first impaired station downstream of a proposed project will be applied to the land disturbance permit requirements. The applicant will have to demonstrate with IDEAL that the annual pollutant of concern loading for the site in a developed condition will be reduced by the respective amount as compared to the pre-developed condition.

  22. Concerns or Questions regarding IDEAL Don Alexander, PE Woolpert Consultants Software Technical Support

  23. Woolpert’s Internal Audit • Consisted of two parts • Evaluate original site county plan reviewed and approved engineer design plan • Field review to compare the design plans against actual site implementation and to determine if the EPSC features actually implemented were effective at reducing erosion and sedimentation at construction sites such that sediment was being retained to achieve MEP

  24. Sites selected • 30 construction sites were selected • 12 single family • 2 multi-family • 11 commercial • 5 industrial The number of sites were randomly selected from within each classification as determined using the total population of active sites within each classification and active at time of inspection

  25. Plan Review Audit Results • Summary of Most Common Plan Review Deficiencies: • Disturbed limits not shown • Soil type not denoted • No sequence bar chart • Lack of EPSC calculations • No drainage area specified for BMPs • Difficult to determine if BMPs sized properly • Lack of details for BMPs • Greenville County/adequate details not used

  26. Field General Scores • Common Issues at all 30 Sites • No Design Plans Available • No Inspection Logs Available • No Stabilization of Inactive Areas

  27. Field Review Results • Summary of Most Common Field Review Deficiencies: • No geotextile layer in rock check dams and construction entrances • Lack of maintenance of BMPs • Inadequate fabric height for silt fences • Inadequate fabric depth for filter fabric inlet protection • Erosion and damage at outlets • No protection provided at several inlets

  28. Plan Review Conclusions and Recommendations • Add requirements to plan review checklist for sites that drain to impaired/303d/TMDL streams • Review CSPR and Internal Plan Reviewer training materials and make appropriate revisions per results of audit • Emphasize that EPSC Plans must include design calculations for all EPSC BMPs • Recommend use of Greenville County details or “equivalent” if available for a particular BMP

  29. Plan Review Conclusions and Recommendations • Provide in-house refresher training for plan reviewers to incorporate results of audit and highlight most common plan review deficiencies: • Lack of EPSC calculations • Disturbed limits not shown • No sequence bar chart • Soil type not denoted • Lack of standard details for BMPs • Greenville County standard details not used • Highlight specific BMP deficiencies

  30. Field Inspection Conclusion and Recommendations • Provide in-house refresher training to incorporate results of audit and highlight most common field inspection deficiencies: • Lack of inspection logs • Lack of filter fabric in appropriate BMPs • No project plans are kept on site • Improper site stabilization • Poor maintenance of BMPs • Inadequate fabric height for silt fence and depth for filter fabric inlet protection • Erosion and damage at outlets • No protection provided at several inlets

  31. Engineer’s Survey Results • The majority still use some version of Hydraflow or Sedcad 4 • Pre-Design meetings last too long and could be limited to 30 minutes if all involved work briskly through the checklist • Exempt owners from Pre-Design meetings if they understand the process, owner requirements and liabilities • 50% would be in favor of having a credit card option for fee payments

  32. Engineer’s Survey Continued • 60% are in favor of going to an electronic process if it saves time and resources thus money to their client • 71% who answered this question favored the subdivision approval process being done electronically • 40% would be in favor of using the Charleston approach to NOI and permit approval • Majority of the general comments were in regards to our requirements being above and beyond SCDHEC’s

  33. Hydrologic and Hydraulic Software • Staff heard that AutoCADD would no longer support Hydraflow • Based on survey results most still use some version of this software • LDD will continue using Hydraflow and Sedcad as the standard software we train our plan review staff to know and use • We will continue to listen to the engineering community on it’s ease of availability and support from the software manufacturer

  34. Pre-Design Meetings • We will commit to continue the practice of scheduling the meeting to take place within 6 days from request • We will commit to keeping meeting times to no more than 45 to 60 minutes in length • We will not over run the scheduled meeting time or make the next appointment wait past their time • We will let the Design Professional do most of the talking as they provide us with the needed information regarding their proposed design • To meet our commitments the engineer must also commit to …

  35. Expectations of the Engineering Community • Provide options that will meet the county’s post construction water quality permit requirements • In order to receive a permit number at the conclusion of the meeting be prepared with all specifics noted on the next slide • Will not debate “Non-standard design manual approaches” during meeting instead will require proposed approach to go through the formal concept review process • If specifics that meet the design manual are not met and more discussion is needed with the time remaining the meeting will become a development conference

  36. Pre-Design Meeting Focus • Design Professional will come to the meeting prepared to explain how they will address in their design the three major elements of permit compliance • Peak Rate Attenuation • Sedimentology • Post Construction Water Quality • Identify potential areas of off site impacts • Explain what parts of the site will require the most attention to meet the requirements

  37. Designer’s Preparation Prior to the Meeting • Familiarize yourself with the storm water permit requirements and design manual • Familiarize yourself with other local, state and federal regulatory requirements and ordinances • Field visit of the site to understand existing site conditions • Review project files for critical information if part of a previously permitted project or larger common plan • Prepare a vicinity map with existing conditions and proposed development plan • Identify potential storm water management features • Complete the Pre-Design Registry Form

  38. Exempted Owners from Pre-Design Meeting • Will exempt developers/utility providers who regularly work in construction and are aware of EPA requirements • Owner will still need to sign an acknowledgement form (a tool in potential enforcement action) • Signed acknowledgement will be included in submittal package • They will receive copy of Pre-Design summary form outlining project scope, impacts and proposed solution

  39. Owner at Pre-Design Meeting • Owners who’s primary business in not construction will be required to attend • Owner packet will no longer be explained in detail just that it’s mandatory that they read and understand their liabilities and responsibilities • If they have questions ask their design professional to explain responsibilities • Signed acknowledgement form (which is used for enforcement and magistrate fines) must be included in the submittal package

  40. County verses SCDHEC’s or other Upstate City/County Requirements • Greenville County is a Phase I MS4 permit holder verses Phase II MS4 permit holders • Phase I’s must meet higher standard for post construction water quality • IDEAL software model is how we meet this higher standard requirements • GC has had a permit since 2001 vs. 2007 • Phase II permit holders have not gone through a SCDHEC audit yet

  41. County verses SCDHEC or other Upstate City/County Requirements • We are guaranteeing a 10 work day plan review turn around time vs. a 20 work day turn around • We are reviewing a higher volume of plans verses these other local/MS4 agencies • Need a standard format and software to meet this guarantee

  42. 10 Business Day Turn Around • Development Community desired a quicker turn around time than required by state law • Construction Boom years coupled with limited county manpower staffing made this difficult • Stakeholders group agreed that a standard software and submittal package format would allow staff to review plans quicker for permit issuance

  43. Times have Changed The development community may have different needs today than 10 years ago

  44. Options for Plan Review Submittals • If the development community feels that engineering cost is a more important factor than time we can offer alternatives • Standard of 20 day turn around • County’s Current 10 day turn around • Expedited Review

  45. State Standard 20 day turn around • Pre-Design Meeting not required • Engineer can submit using any software model of their choice • Must provide a network diagram and pre and post maps as currently required by SCDHEC • Use Standard SCDHEC checklist but with our 25 year storm design standard • Must use IDEAL to meet our Phase I MS4 permit requirements for post construction water quality • Must address Tree Ordinance and any other county related zoning requirements specific to this project that effects land disturbance • This permit submittal option fee will cost $600 more than 10 day turn around option since it will take additional staff time to perform the needed sub-area delineation and verify travel paths, lengths, slopes, etc

  46. County’s Current 10 day turn around • Pre-Design meeting must be held • Must use Hydraflow or SedCad software • Must include the 360 area map with delineated areas, CN’s, slopes, and flow path lengths • Must provide chart with input data to support hydrology model & network diagram • Must address all the key information in the narrative especially anything that outlines master plan assumptions & how you will meet water quality standards

  47. Expedited Review • Would mimic SCDHEC’s process and required fee • Pre-Design meeting would be required prior to submittal • Friday noon submittal deadline with paid $5000 additional expedited review fee • Monday morning 9:00 am meeting to review • Thursday morning 9:00 am meeting to discuss reviewer’s comments • Friday 2:00 pm deadline for Engineer to address comments and re-submit • Friday 5:00 pm County Plan Reviewer Preliminary Approval

  48. Concept Plan Process • Use if proposing innovative design approaches not currently in design manual or if deviations from the design manual are proposed • Submit anytime after pre-design meeting with check for staff review (the sooner in the process the better) • Staff will review within 10 days and share their findings with County Engineer, who will make final decision on approval • If approved the concept review fee will be subtracted from the plan review fee • See section 3.1.4 of design manual for required submittal data

  49. Number of Permits Issued • 2006/07 – 301 grading permits; 58 subdivision road plans • 2007/08 – 338 grading permits; 33 subdivision road plans • 2008-09 – 250 grading permits; 3 subdivision road plans • 2009/10 - 253 grading permits(61 subdivision renewals); 2 subdivision road plans • 2010/11 – 196 grading permits; 1 subdivision road plan • 2011/12 (1st six months) – 95 grading permits; 0 subdivision road plans

  50. Subdivision’s On-Hold/Re-permitted(status since 10/7/09)

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