land development division engineer forum february 23, 2012 conference room d

LAND DEVELOPMENT LAND DEVELOPMENT DIVISIONDIVISION

ENGINEER FORUMENGINEER FORUM

February 23, 2012February 23, 2012

Conference Room D Conference Room D

Today’s AgendaToday’s Agenda

• 2009 SCDHEC’s Audit Findings2009 SCDHEC’s Audit Findings

• 2010 Woolpert’s Internal Audit Findings2010 Woolpert’s Internal Audit Findings

• Results from Summer 2011 SurveyResults from Summer 2011 Survey

• Proposed ChangesProposed Changes

• EPA and SCDHEC Regulation ForecastEPA and SCDHEC Regulation Forecast

• Status and expected contents of our Status and expected contents of our next NPDES MS4 permit next NPDES MS4 permit

Land Development Land Development RegulationsRegulations• Land Development Regulations UpdateLand Development Regulations Update• Stakeholder ApproachStakeholder Approach• Time Frame – Begin March 2012 & up Time Frame – Begin March 2012 & up

to 1 year to complete stakeholder to 1 year to complete stakeholder reviewreview

• Includes LID’s, TND’s, Centers & Includes LID’s, TND’s, Centers & Corridors, Traffic Impact, etc.Corridors, Traffic Impact, etc.

• Update Zoning Ordinance to reflect Update Zoning Ordinance to reflect changes in LDR changes in LDR

SCDHEC’s Audit ResultsSCDHEC’s Audit Results

• EPA guidance requires SCDHEC to conduct an EPA guidance requires SCDHEC to conduct an in-depth audit at least once every five (5) in-depth audit at least once every five (5) yearsyears

• In March of 2009 SCDHEC held a two day In March of 2009 SCDHEC held a two day audit covering all 13 elements of our MS4 audit covering all 13 elements of our MS4 PermitPermit

• The conclusion was Greenville County’s The conclusion was Greenville County’s program was satisfactory with deficiencies in program was satisfactory with deficiencies in two elements:two elements:– Construction Site RunoffConstruction Site Runoff– Public Education and Public ParticipationPublic Education and Public Participation

DHEC’s Audit CommentsDHEC’s Audit Comments

• …” …” The County needs to improve The County needs to improve documentation of how they are determining documentation of how they are determining that BMP’s proposed on sites that drain to that BMP’s proposed on sites that drain to Impaired Waters (both 303(d) listed and Impaired Waters (both 303(d) listed and those included in a TMDL) are adequate to those included in a TMDL) are adequate to address the pollutant of concern in the address the pollutant of concern in the receiving water body.”receiving water body.”

• ““Overall, Greenville County is not effectively Overall, Greenville County is not effectively approving construction site plans to MEP approving construction site plans to MEP standards. The MS4’s focus must be on standards. The MS4’s focus must be on water quality.” water quality.”

SCDHEC Audit CommentsSCDHEC Audit Comments

• Silver Meadows Phase III: SCR10I232Silver Meadows Phase III: SCR10I232• 1. Greenville County application form says 25 disturbed acres; NOI says 1. Greenville County application form says 25 disturbed acres; NOI says

23.9 disturbed acres23.9 disturbed acres• 2. One engineer signed and sealed Greenville County application and 2. One engineer signed and sealed Greenville County application and

different engineer signed and sealed plans and NOIdifferent engineer signed and sealed plans and NOI• 3. NOI indicates impacts to 121' stream-not mentioned or shown on plans; 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 plansthe area of impacts should be clearly identified and shown on the plans• 4. No wetlands/ waters of the State delineation on plans-impacts to 4. No wetlands/ waters of the State delineation on plans-impacts to

wetlands/ waters of the State cannot be assessed/ reviewed if the wetlands/ waters of the State cannot be assessed/ reviewed if the delineation is not shown on the plans. Surveyed delineation must be shown 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 on the plans; plans must be reviewed to ensure that appropriate BMPs are provided to prevent sediment from washing into wetlands/ waters of the provided to prevent sediment from washing into wetlands/ waters of the State and to ensure that basins/ traps/ any structures shown in the SWPPP State and to ensure that basins/ traps/ any structures shown in the SWPPP are not being constructed in wetlands/ waters of the State without are not being constructed in wetlands/ waters of the State without appropriate Corps' 404 permit and SCDHEC 401 certification. See Section appropriate Corps' 404 permit and SCDHEC 401 certification. See Section 2.1C of SCR100000. If the entire SWPPP cannot be implemented and a 404 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 permit is needed for the associated impacts to wetlands/ waters of the State, then NPDES coverage cannot be issued until 404 permit has been 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 issued and is effective (SC DHEC 401 certification of the 404 permit must be issued for 404 permit to be issued and effective).be issued for 404 permit to be issued and effective).

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 post development 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.

6. 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.

7. 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. 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 grading13. 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

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.

18.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.

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 maintained22. Riprap sediment dike-no detail provided but called for on plans23. Sediment check detail-no detail provided but called for on plans24. 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

Springs at Greenville Apartments: SCR10K4711. Pond maintenance plan and Flogard Plus maintenance plan not provided2. 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 post development calculations; also, the analysis points should be the points where flows leave the site/ property. For example, the analysis point for pre development 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 post development 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.

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.

11.Limits of disturbance shown through the western wetlands area12.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. 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 entrance17. 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 plans22. Permanent diversion swale-no detail provided but called for on plans23. Check dam detail-cleanout information not listed24. Sediment trap detail: sizing information only provided for traps 1 and 2;

however, several other traps are shown on the plans25. Riprap dike-no detail provided but called for on plans26. Diversion ditch and diversion berm details-only detail provided for diversion

swale; make sure labeled consistently on plans and details

Upstate Commercial Park: SCRl0I6641. 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 land disturbing 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 plans5. 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

6. Construction sequence not specific far this phase-mentions clearing and grubbing for basins and installation of basins; according to plans, basins are existing

Lake Conestee Nature Park Phase 2 Paved Trail: SCR10K1371. BIO impairment not addressed-see item 22 of checklist and section 3.4C.2.c; SWPPP must contain evaluation of proposed BMPs2. 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 roadway3. Maintenance requirements for vegetated swale not included-SWPPP mentions native plants but no specific maintenance plan provided4. 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 plans5. No limits of disturbance shown on the plans6. Double row of silt fence not provided where 50' undisturbed buffer cannot be maintained between wetlands/waters of the State and the disturbed area7. Construction entrance-not shown on plans; must be provided; also detail must be provided8. 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

Creekwood S/D Ph II, PN SCR10J644, File No. 23-08-08-O5l. 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.

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. 23-08-09-031. 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.4. Sheet C2.2 refers to the Detention Basin maintenance meeting the

Pickens County Stormwater Regulations. The basin is in Greenville County.

5. 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.

Goodwin Farms, PN SCR10J143, File No. 23-08-05-22l. 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

Assistant County Assistant County Administrator’s ResponseAdministrator’s Response

• Will review its internal Plan Reviewer training Will review its internal Plan Reviewer training requirements and make appropriate requirements and make appropriate adjustmentsadjustments

• Staff will hold joint training class with DHEC staff Staff will hold joint training class with DHEC staff to get better understanding of expectationsto get better understanding of expectations

• Provide staff with in-house refresher training Provide staff with in-house refresher training and incorporate the results from this audit and incorporate the results from this audit reportreport

• Continually evaluate its construction plan review Continually evaluate its construction plan review program to find improvementsprogram to find improvements

Impaired Water ResponseImpaired Water Response

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

TMDL Compliance ResponseTMDL Compliance Response

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

Concerns or Questions Concerns or Questions regarding IDEALregarding IDEAL

Don Alexander, PEDon Alexander, PE

Woolpert ConsultantsWoolpert Consultants

Software Technical Support Software Technical Support

Woolpert’s Internal AuditWoolpert’s Internal Audit

• Consisted of two partsConsisted of two parts– Evaluate original site county plan reviewed and Evaluate original site county plan reviewed and

approved engineer design planapproved engineer design plan– Field review to compare the design plans Field review to compare the design plans

against actual site implementation and to against actual site implementation and to determine if the EPSC features actually determine if the EPSC features actually implemented were effective at reducing implemented were effective at reducing erosion and sedimentation at construction sites erosion and sedimentation at construction sites such that sediment was being retained to such that sediment was being retained to achieve MEP achieve MEP

Sites selectedSites selected

• 30 construction sites were selected30 construction sites were selected– 12 single family12 single family– 2 multi-family2 multi-family– 11 commercial11 commercial– 5 industrial5 industrial

The number of sites were randomly selected The number of sites were randomly selected from within each classification as determined from within each classification as determined using the total population of active sites within using the total population of active sites within each classification and active at time of each classification and active at time of inspectioninspection

Plan Review Audit ResultsPlan Review Audit Results

• Summary of Most Common Plan Review Summary of Most Common Plan Review Deficiencies:Deficiencies:– Disturbed limits not shownDisturbed limits not shown– Soil type not denotedSoil type not denoted– No sequence bar chartNo sequence bar chart– Lack of EPSC calculationsLack of EPSC calculations– No drainage area specified for BMPsNo drainage area specified for BMPs– Difficult to determine if BMPs sized properlyDifficult to determine if BMPs sized properly– Lack of details for BMPsLack of details for BMPs– Greenville County/adequate details not used Greenville County/adequate details not used

Field General ScoresField General Scores

• Common Issues at all 30 SitesCommon Issues at all 30 Sites– No Design Plans AvailableNo Design Plans Available– No Inspection Logs AvailableNo Inspection Logs Available– No Stabilization of Inactive AreasNo Stabilization of Inactive Areas

Field Review ResultsField Review Results

• Summary of Most Common Field Review Summary of Most Common Field Review Deficiencies:Deficiencies:– No geotextile layer in rock check dams and No geotextile layer in rock check dams and

construction entrancesconstruction entrances– Lack of maintenance of BMPsLack of maintenance of BMPs– Inadequate fabric height for silt fencesInadequate fabric height for silt fences– Inadequate fabric depth for filter fabric inlet Inadequate fabric depth for filter fabric inlet

protectionprotection– Erosion and damage at outletsErosion and damage at outlets– No protection provided at several inletsNo protection provided at several inlets

Plan Review Conclusions and Plan Review Conclusions and RecommendationsRecommendations

• Add requirements to plan review checklist for Add requirements to plan review checklist for sites that drain to impaired/303d/TMDL sites that drain to impaired/303d/TMDL streamsstreams

• Review CSPR and Internal Plan Reviewer Review CSPR and Internal Plan Reviewer training materials and make appropriate training materials and make appropriate revisions per results of auditrevisions per results of audit

• Emphasize that EPSC Plans must include Emphasize that EPSC Plans must include design calculations for all EPSC BMPsdesign calculations for all EPSC BMPs

• Recommend use of Greenville County details Recommend use of Greenville County details or “equivalent” if available for a particular or “equivalent” if available for a particular BMP BMP

Plan Review Conclusions and Plan Review Conclusions and RecommendationsRecommendations

• Provide in-house refresher training for plan Provide in-house refresher training for plan reviewers to incorporate results of audit and reviewers to incorporate results of audit and highlight most common plan review highlight most common plan review deficiencies:deficiencies:– Lack of EPSC calculationsLack of EPSC calculations– Disturbed limits not shownDisturbed limits not shown– No sequence bar chartNo sequence bar chart– Soil type not denotedSoil type not denoted– Lack of standard details for BMPsLack of standard details for BMPs– Greenville County standard details not usedGreenville County standard details not used– Highlight specific BMP deficiencies Highlight specific BMP deficiencies

Field Inspection Conclusion and Field Inspection Conclusion and RecommendationsRecommendations• Provide in-house refresher training to incorporate Provide in-house refresher training to incorporate

results of audit and highlight most common field results of audit and highlight most common field inspection deficiencies:inspection deficiencies:– Lack of inspection logsLack of inspection logs– Lack of filter fabric in appropriate BMPsLack of filter fabric in appropriate BMPs– No project plans are kept on siteNo project plans are kept on site– Improper site stabilizationImproper site stabilization– Poor maintenance of BMPsPoor maintenance of BMPs– Inadequate fabric height for silt fence and depth for filter Inadequate fabric height for silt fence and depth for filter

fabric inlet protectionfabric inlet protection– Erosion and damage at outletsErosion and damage at outlets– No protection provided at several inlets No protection provided at several inlets

Engineer’s Survey ResultsEngineer’s Survey Results

• The majority still use some version of The majority still use some version of Hydraflow or Sedcad 4Hydraflow or Sedcad 4

• Pre-Design meetings last too long and Pre-Design meetings last too long and could be limited to 30 minutes if all could be limited to 30 minutes if all involved work briskly through the checklistinvolved work briskly through the checklist

• Exempt owners from Pre-Design meetings Exempt owners from Pre-Design meetings if they understand the process, owner if they understand the process, owner requirements and liabilities requirements and liabilities

• 50% would be in favor of having a credit 50% would be in favor of having a credit card option for fee payments card option for fee payments

Engineer’s Survey Engineer’s Survey ContinuedContinued• 60% are in favor of going to an electronic 60% are in favor of going to an electronic

process process ifif it saves time and resources thus it saves time and resources thus money to their clientmoney to their client

• 71% who answered this question favored 71% who answered this question favored the subdivision approval process being done the subdivision approval process being done electronicallyelectronically

• 40% would be in favor of using the 40% would be in favor of using the Charleston approach to NOI and permit Charleston approach to NOI and permit approval approval

• Majority of the general comments were in Majority of the general comments were in regards to our requirements being above regards to our requirements being above and beyond SCDHEC’sand beyond SCDHEC’s

Hydrologic and Hydraulic Hydrologic and Hydraulic SoftwareSoftware• Staff heard that AutoCADD would no Staff heard that AutoCADD would no

longer support Hydraflowlonger support Hydraflow• Based on survey results most still use Based on survey results most still use

some version of this softwaresome version of this software• LDD will continue using Hydraflow and LDD will continue using Hydraflow and

Sedcad as the standard software we train Sedcad as the standard software we train our plan review staff to know and useour plan review staff to know and use

• We will continue to listen to the We will continue to listen to the engineering community on it’s ease of engineering community on it’s ease of availability and support from the software availability and support from the software manufacturer manufacturer

Pre-Design MeetingsPre-Design Meetings

• We will commit to continue the practice of We will commit to continue the practice of scheduling the meeting to take place within 6 days scheduling the meeting to take place within 6 days from requestfrom request

• We will commit to keeping meeting times to no We will commit to keeping meeting times to no more than 45 to 60 minutes in lengthmore than 45 to 60 minutes in length

• We will not over run the scheduled meeting time We will not over run the scheduled meeting time or make the next appointment wait past their timeor make the next appointment wait past their time

• We will let the Design Professional do most of the We will let the Design Professional do most of the talking as they provide us with the needed talking as they provide us with the needed information regarding their proposed design information regarding their proposed design

• To meet our commitments the engineer must also To meet our commitments the engineer must also commit to … commit to …

Expectations of the Expectations of the Engineering CommunityEngineering Community

• Provide options that will meet the county’s post Provide options that will meet the county’s post construction water quality permit requirementsconstruction water quality permit requirements

• In order to receive a permit number at the In order to receive a permit number at the conclusion of the meeting be prepared with all conclusion of the meeting be prepared with all specifics noted on the next slidespecifics noted on the next slide

• Will not debate “Non-standard design manual Will not debate “Non-standard design manual approaches” during meeting instead will require approaches” during meeting instead will require proposed approach to go through the formal proposed approach to go through the formal concept review process concept review process

• If specifics that meet the design manual are not If specifics that meet the design manual are not met and more discussion is needed with the time met and more discussion is needed with the time remaining the meeting will become a remaining the meeting will become a development conference development conference

Pre-Design Meeting FocusPre-Design Meeting Focus

• Design Professional will come to the Design Professional will come to the meeting prepared to explain how they will meeting prepared to explain how they will address in their design the three major address in their design the three major elements of permit complianceelements of permit compliance– Peak Rate AttenuationPeak Rate Attenuation– SedimentologySedimentology– Post Construction Water QualityPost Construction Water Quality– Identify potential areas of off site impactsIdentify potential areas of off site impacts– Explain what parts of the site will require the Explain what parts of the site will require the

most attention to meet the requirementsmost attention to meet the requirements

Designer’s Preparation Prior to Designer’s Preparation Prior to the Meetingthe Meeting • Familiarize yourself with the storm water permit Familiarize yourself with the storm water permit

requirements and design manualrequirements and design manual• Familiarize yourself with other local, state and Familiarize yourself with other local, state and

federal regulatory requirements and ordinancesfederal regulatory requirements and ordinances• Field visit of the site to understand existing site Field visit of the site to understand existing site

conditionsconditions• Review project files for critical information if part of a Review project files for critical information if part of a

previously permitted project or larger common plan previously permitted project or larger common plan • Prepare a vicinity map with existing conditions and Prepare a vicinity map with existing conditions and

proposed development plan proposed development plan • Identify potential storm water management features Identify potential storm water management features • Complete the Pre-Design Registry FormComplete the Pre-Design Registry Form

Exempted Owners from Pre-Exempted Owners from Pre-Design MeetingDesign Meeting

• Will exempt developers/utility providers Will exempt developers/utility providers who regularly work in construction and are who regularly work in construction and are aware of EPA requirementsaware of EPA requirements– Owner will still need to sign an Owner will still need to sign an

acknowledgement form (a tool in potential acknowledgement form (a tool in potential enforcement action)enforcement action)

– Signed acknowledgement will be included in Signed acknowledgement will be included in submittal packagesubmittal package

– They will receive copy of Pre-Design summary They will receive copy of Pre-Design summary form outlining project scope, impacts and form outlining project scope, impacts and proposed solution proposed solution

Owner at Pre-Design Owner at Pre-Design MeetingMeeting• Owners who’s primary business in not Owners who’s primary business in not

construction will be required to attend construction will be required to attend • Owner packet will no longer be explained Owner packet will no longer be explained

in detail just that it’s mandatory that they in detail just that it’s mandatory that they read and understand their liabilities and read and understand their liabilities and responsibilitiesresponsibilities

• If they have questions ask their design If they have questions ask their design professional to explain responsibilitiesprofessional to explain responsibilities

• Signed acknowledgement form (which is Signed acknowledgement form (which is used for enforcement and magistrate fines) used for enforcement and magistrate fines) must be included in the submittal package must be included in the submittal package

County verses SCDHEC’s or County verses SCDHEC’s or other Upstate City/County other Upstate City/County RequirementsRequirements• Greenville County is a Phase I MS4 Greenville County is a Phase I MS4

permit holder verses Phase II MS4 permit holder verses Phase II MS4 permit holders permit holders – Phase I’s must meet higher standard for Phase I’s must meet higher standard for

post construction water qualitypost construction water quality– IDEAL software model is how we meet this IDEAL software model is how we meet this

higher standard requirementshigher standard requirements– GC has had a permit since 2001 vs. 2007 GC has had a permit since 2001 vs. 2007 – Phase II permit holders have not gone Phase II permit holders have not gone

through a SCDHEC audit yet through a SCDHEC audit yet

County verses SCDHEC or County verses SCDHEC or other Upstate City/County other Upstate City/County RequirementsRequirements• We are guaranteeing a 10 work day We are guaranteeing a 10 work day

plan review turn around time vs. a 20 plan review turn around time vs. a 20 work day turn aroundwork day turn around

• We are reviewing a higher volume of We are reviewing a higher volume of plans verses these other local/MS4 plans verses these other local/MS4 agenciesagencies

• Need a standard format and software Need a standard format and software to meet this guarantee to meet this guarantee

10 Business Day Turn 10 Business Day Turn AroundAround• Development Community desired a quicker Development Community desired a quicker

turn around time than required by state law turn around time than required by state law

• Construction Boom years coupled with Construction Boom years coupled with limited county manpower staffing made this limited county manpower staffing made this difficultdifficult

• Stakeholders group agreed that a standard Stakeholders group agreed that a standard software and submittal package format software and submittal package format would allow staff to review plans quicker for would allow staff to review plans quicker for permit issuance permit issuance

Times have ChangedTimes have Changed

The development community The development community may have different needs may have different needs today than 10 years agotoday than 10 years ago

Options for Plan Review Options for Plan Review SubmittalsSubmittals

• If the development community feels If the development community feels that engineering cost is a more that engineering cost is a more important factor than time we can important factor than time we can offer alternatives offer alternatives

• Standard of 20 day turn aroundStandard of 20 day turn around

• County’s Current 10 day turn aroundCounty’s Current 10 day turn around

• Expedited Review Expedited Review

State Standard 20 day turn State Standard 20 day turn aroundaround• Pre-Design Meeting not requiredPre-Design Meeting not required• Engineer can submit using any software model of their choiceEngineer can submit using any software model of their choice• Must provide a network diagram and pre and post maps as Must provide a network diagram and pre and post maps as

currently required by SCDHECcurrently required by SCDHEC• Use Standard SCDHEC checklist but with our 25 year storm Use Standard SCDHEC checklist but with our 25 year storm

design standarddesign standard• Must use IDEAL to meet our Phase I MS4 permit requirements Must use IDEAL to meet our Phase I MS4 permit requirements

for post construction water qualityfor post construction water quality• Must address Tree Ordinance and any other county related Must address Tree Ordinance and any other county related

zoning requirements specific to this project that effects land zoning requirements specific to this project that effects land disturbancedisturbance

• This permit submittal option fee will cost $600 more than 10 This permit submittal option fee will cost $600 more than 10 day turn around option since it will take additional staff time day turn around option since it will take additional staff time to perform the needed sub-area delineation and verify travel to perform the needed sub-area delineation and verify travel paths, lengths, slopes, etc paths, lengths, slopes, etc

County’s Current 10 day turn County’s Current 10 day turn aroundaround• Pre-Design meeting must be heldPre-Design meeting must be held• Must use Hydraflow or SedCad softwareMust use Hydraflow or SedCad software• Must include the 360 area map with Must include the 360 area map with

delineated areas, CN’s, slopes, and flow path delineated areas, CN’s, slopes, and flow path lengths lengths

• Must provide chart with input data to Must provide chart with input data to support hydrology model & network diagramsupport hydrology model & network diagram

• Must address all the key information in the Must address all the key information in the narrative especially anything that outlines narrative especially anything that outlines master plan assumptions & how you will master plan assumptions & how you will meet water quality standards meet water quality standards

Expedited ReviewExpedited Review

• Would mimic SCDHEC’s process and required feeWould mimic SCDHEC’s process and required fee• Pre-Design meeting would be required prior to Pre-Design meeting would be required prior to

submittalsubmittal• Friday noon submittal deadline with paid $5000 Friday noon submittal deadline with paid $5000

additional expedited review feeadditional expedited review fee• Monday morning 9:00 am meeting to reviewMonday morning 9:00 am meeting to review• Thursday morning 9:00 am meeting to discuss Thursday morning 9:00 am meeting to discuss

reviewer’s commentsreviewer’s comments• Friday 2:00 pm deadline for Engineer to address Friday 2:00 pm deadline for Engineer to address

comments and re-submitcomments and re-submit• Friday 5:00 pm County Plan Reviewer Preliminary Friday 5:00 pm County Plan Reviewer Preliminary

Approval Approval

Concept Plan ProcessConcept Plan Process

• Use if proposing innovative design approaches Use if proposing innovative design approaches not currently in design manual or if deviations not currently in design manual or if deviations from the design manual are proposedfrom the design manual are proposed

• Submit anytime after pre-design meeting with Submit anytime after pre-design meeting with check for staff review (the sooner in the process check for staff review (the sooner in the process the better)the better)

• Staff will review within 10 days and share their Staff will review within 10 days and share their findings with County Engineer, who will make findings with County Engineer, who will make final decision on approvalfinal decision on approval

• If approved the concept review fee will be If approved the concept review fee will be subtracted from the plan review feesubtracted from the plan review fee

• See section 3.1.4 of design manual for required See section 3.1.4 of design manual for required submittal data submittal data

Number of Permits IssuedNumber of Permits Issued

• 2006/07 – 301 grading permits; 58 subdivision road 2006/07 – 301 grading permits; 58 subdivision road plansplans

• 2007/08 – 338 grading permits; 33 subdivision road 2007/08 – 338 grading permits; 33 subdivision road plansplans

• 2008-09 – 250 grading permits; 3 subdivision road 2008-09 – 250 grading permits; 3 subdivision road plansplans

• 2009/10 - 253 grading permits(61 subdivision 2009/10 - 253 grading permits(61 subdivision renewals); 2 subdivision road plansrenewals); 2 subdivision road plans

• 2010/11 – 196 grading permits; 1 subdivision road 2010/11 – 196 grading permits; 1 subdivision road planplan

• 2011/12 (12011/12 (1stst six months) – 95 grading permits; six months) – 95 grading permits; 0 subdivision road plans 0 subdivision road plans

Subdivision’s On-Hold/Re-Subdivision’s On-Hold/Re-permittedpermitted

(status since 10/7/09)(status since 10/7/09)BUILDING CODES "HOLD" - 12/6/11 Permit Project Name INSP DATE SENT TO CODES DATE RELEASED 06-6476 SHEAD PROPERTIES (09-1241) QM 10/6/2009 12/18/2009 05-6326 PENNINGTON PARK JB 10/6/2009 closeout 10/27/11 06-6508 ENOREE TRACE JB 10/6/2009 closeout 4/12/10 06-6453 WETHERILL PARK QM 10/6/2009 06-6566 NORTH RIDGE SUBDIVISION JB 10/6/2009 closeout 06-6630 RIDGEWATER PH. 1 JF 10/7/2009 05-6197 BEAUMONT DS 10/7/2009 closeout 11/9/11 07-6732 FURMAN PLACE DS 10/7/2009 05-6077 BEL-AIRE COMMONS DS 10/7/2009 07-6676 INGLES MARKETS DS 10/7/2009 05-6161 HALTON MEDICAL JS 10/7/2009 closeout 10/21/10 06-6582 GRIFFIN PARK (09-1247) JF 10/7/2009 02-5153 VILLAGGIO DI MONTEBELLO DS 10/7/2009 closeout 11/9/11 07-6673 VILLAGE @ WINDSOR CREEK JS 10/9/2009 9/7/2010 05-6072 LANDING @ SAVANNAH POINTE JS 10/9/2009 05-6072 THE COVE @ SAVANNAH POINTE PH 1 JS 10/9/2009 11/5/2010 06-6507 ELLINGTON PARK JS 10/9/2009 12/29/2010 05-6275 FIVE FORKS PLANTATION (10-1183) JS 10/9/2009 3/23/2011 07-6760 TUSCANY FALLS PH 1 (10-1023) JS 10/9/2009 2/15/2010 07-6762 HARRISON COVE (09-1256) JS 10/9/2009 3/15/2011 00-4464 WATTS/TRAVELERS RIDGE DS 10/13/2009 04-5907 LENHARDT CREEK (11-1045) DS 10/13/2009 close out 10/27/11 07-6652 LAKE ROBINSON HEIGHTS/BLUE WATER JB 10/13/2009 9/9/2011 04-5827 LANSDOWNE (10-1019) JF 10/13/2009 3/11/2010 05-6314 WATERMILL (only certain lots) (11-1055) JF 10/29/2009 5/16/2011 04-5987 SHELLBROOK PLANTATION (11-1031) JS 10/29/2009 6/6/2011 05-6095 TAMARON PARK TR 11/16/2009 04-5751 FAIRBROOKE JF 12/22/2009 close out 10/27/11 07-6736 THE RESERVE@GREEN VALLEY DS 12/22/2009 06-6379 HUNTER RIDGE PH. IV DS 12/22/2009 05-6180 WINDSOR CREEK JS 12/22/2009 06-6543 SOUTHSIDE ESTATES QM 12/22/2009 06-6552 RIVERBEND ESTATES (10-1010) JB 12/22/2009 1/26/2010 06-6435 BRUTONTOWN PH. 1-A (10-1007) DS 12/22/2009 2/19/2010 05-6343 LADSON LAKE QM 12/23/2009 05-6141 PLANTATION GREEN PH. II (10-1035) TR 12/28/2009 3/29/2010 04-5783 ASHMORE SPRINGS PH. 3 JF 1/29/2010 07-6939 MCRAE PARK (11-1120) JS 1/29/2010 10/14/2011 07-6883 THE GARDENS @ ROSE RESERVE (10-1033) JB 1/29/2010 4/1/2010 05-6305 HOLLINGTON JS 1/29/2010 8/10/2011 07-6695 KILGORE FARMS - PH.4 (10-1036) JS 1/29/2010 3/2/2010 06-6358 HAWTHORNE RIDGE TR 1/29/2010 06-6370 CLEAR SPRINGS TR 2/1/2010 05-6054 PELHAM VILLAGE (FKA VILLAS OF TOSCANO)(11-1133) TR 2/1/2010 05-6203 CEDARCREST/GREYTHORNE (11-1078) JF 2/1/2010 11/4/2011 04-5745 BARNETT VALLEY JB 2/5/2010 06-6428 CARDINAL CREEK TOWNHOMES (11-1175) TR 4/26/2010 05-6075 GILDER CHASE (09-1239) JS 5/10/2010 05-6188 VALLEY VIEW/SUMMIT (09-1118) JB 6/2/2010 6/29/2010 01-4973 PONDICHERRY/CITY LIGHTS (10-1043) 7/20/2010 07-6746 COURTYARDS @ WEST GEORGIA JF 11/2/11 06-6465 WILLIMON ESTATES(FKA WILLIMON PLACE) QM 12/6/2011 PROJECTS SUBMITTED FOR RENEWAL/CLOSEOUT

Average Turn AroundAverage Turn Around(We have one of the shortest turn around (We have one of the shortest turn around

commitments in the Upstate)commitments in the Upstate)

• 2010/112010/11– 11stst Submittals – 7.38 Submittals – 7.38

daysdays– Re-submittals - 3.9 Re-submittals - 3.9

daysdays– Modifications - 6.47 Modifications - 6.47

days days

• 2011/12 (12011/12 (1stst six six mo’s)mo’s)– 11stst Submittals – 6.27 Submittals – 6.27

daysdays– Re-submittals – Re-submittals –

3.50 days3.50 days– Modifications – 7.18 Modifications – 7.18

daysdays

SCDHEC NOI ApplicationsSCDHEC NOI Applications

• Greenville County LDD’s processing of NOI Greenville County LDD’s processing of NOI application & forwarding to DHEC along with our application & forwarding to DHEC along with our approval form is a courtesy & not a requirement of approval form is a courtesy & not a requirement of state lawstate law

• Survey says Engineer’s want to maintain this Survey says Engineer’s want to maintain this practice vs getting NOI approval first or Engineer practice vs getting NOI approval first or Engineer filing the NOI directly to DHEC after our preliminary filing the NOI directly to DHEC after our preliminary approval.approval.

• DHEC has outlined their expectation regarding the DHEC has outlined their expectation regarding the completion of their application. We review the completion of their application. We review the application to assist the engineer in identifying application to assist the engineer in identifying items that could delay it’s approval.items that could delay it’s approval.

• LDD does not have the authority to change, modify LDD does not have the authority to change, modify or add to this application. or add to this application.

EPA’s definition of “part of a EPA’s definition of “part of a larger common plan”larger common plan”• Large Construction Activity – development Large Construction Activity – development

or sale that will ultimately disturb equal to or sale that will ultimately disturb equal to or greater than five (5) acresor greater than five (5) acres

• Small Construction Activity – results in land Small Construction Activity – results in land disturbance of equal to or greater than one disturbance of equal to or greater than one acre and less than five acresacre and less than five acres

• EPA & DHEC has stated NOI coverage is EPA & DHEC has stated NOI coverage is required even if disturbing less than one required even if disturbing less than one acre, if included as part of a large common acre, if included as part of a large common plan of development where ultimately plan of development where ultimately disturb equal to more than one acre but disturb equal to more than one acre but less than five (5) acres less than five (5) acres

EPA’S Broad Definition EPA’S Broad Definition Part of Larger Common Plan Part of Larger Common Plan

• Any announcement or piece of Any announcement or piece of documentation (including a sign, public documentation (including a sign, public notice or hearing, sales pitch, notice or hearing, sales pitch, advertisement, drawing, permit advertisement, drawing, permit application, zoning request, computer application, zoning request, computer design) or physical demarcation design) or physical demarcation (including boundary signs, lot stakes, (including boundary signs, lot stakes, surveyor markings) indicating surveyor markings) indicating construction activity may occur on a construction activity may occur on a specific plot specific plot

Common Plan of Development Common Plan of Development or Saleor Sale• Is a contiguous area where multiple, separate & Is a contiguous area where multiple, separate &

distinct construction activities may be taking distinct construction activities may be taking place either simultaneously or on different place either simultaneously or on different schedules schedules

• This includes activities scheduled to occur in This includes activities scheduled to occur in “phases”“phases”

• SCDHEC considers it to be part of a LCP if there SCDHEC considers it to be part of a LCP if there has been land disturbance activities (clearing, has been land disturbance activities (clearing, grading or excavating) resulting in an grading or excavating) resulting in an accumulation of 1 or more disturbed acre since accumulation of 1 or more disturbed acre since 1992 or will exceed the 1 acre limit with future 1992 or will exceed the 1 acre limit with future land disturbing activities land disturbing activities

County Defined verses County Defined verses SCDHECSCDHEC

• Any larger common plan that has no Any larger common plan that has no active construction and/or was not active construction and/or was not previously permitted under a general previously permitted under a general construction permit by SCDHEC but construction permit by SCDHEC but is documented as being previously is documented as being previously permitted by Greenville County and permitted by Greenville County and is in LDD’s databaseis in LDD’s database

Engineering Minimum PlansEngineering Minimum Plans

• Are used when the project scope size or runoff Are used when the project scope size or runoff increase doesn’t qualify under the non-simplified increase doesn’t qualify under the non-simplified requirements but requires the expertise of an engineer requirements but requires the expertise of an engineer

• Engineer certification or supervision of work needed Engineer certification or supervision of work needed due to changes to the drainage system, due to changes to the drainage system, environmentally sensitive downstream conditions or environmentally sensitive downstream conditions or stabilization plan needed for sites disturbed w/out stabilization plan needed for sites disturbed w/out permits & under NOVpermits & under NOV

• Project minimally exceeds simplified criteria in size or Project minimally exceeds simplified criteria in size or runoff increase where LID’s will be used to meet runoff increase where LID’s will be used to meet requirementsrequirements

• Project is simplified in scope or size but is part of a site Project is simplified in scope or size but is part of a site defined by SCDHEC or LDD as a part of a larger defined by SCDHEC or LDD as a part of a larger common plan common plan

Engineer SupervisionEngineer Supervision

• Site requires periodic observation of Site requires periodic observation of construction & a final inspection for design construction & a final inspection for design compliance compliance

• Project does not warrant CEPSCI inspection Project does not warrant CEPSCI inspection level oversightlevel oversight

• Engineer defines the frequency of site visits Engineer defines the frequency of site visits and the general nature of his/her oversightand the general nature of his/her oversight

• This inspection can be made by a This inspection can be made by a representative of his/her office under representative of his/her office under engineer’s supervisionengineer’s supervision

Low Impact Development Low Impact Development Requirement (Green Requirement (Green Infrastructure)Infrastructure)• Rezoning to higher density to meet the Rezoning to higher density to meet the

Centers and Corridors plan would need Centers and Corridors plan would need to use LID’s to meet water quality to use LID’s to meet water quality standardsstandards

• Changes to LDR will incorporate the use Changes to LDR will incorporate the use of LID’s in road right of way applicationsof LID’s in road right of way applications

• Details are being sought from other Details are being sought from other agencies – PDF and CADD formats will agencies – PDF and CADD formats will be provided for engineer’s use be provided for engineer’s use

Steep Slope/Mountainous Steep Slope/Mountainous Grading RequirementsGrading Requirements

• Traditional engineering designs to meet Traditional engineering designs to meet storm water management are difficult in storm water management are difficult in mountainous terrainmountainous terrain

• To meet requirements 65 percent of the To meet requirements 65 percent of the site should be preserved in a forested or site should be preserved in a forested or native soil and the effective imperious native soil and the effective imperious surface of the area must be <10%surface of the area must be <10%

• Runoff from imperious area must drain to Runoff from imperious area must drain to native buffer areas or into an LID featurenative buffer areas or into an LID feature

Small Residential Small Residential SubdivisionsSubdivisions• Full Dispersion or Partial w/ LID features Full Dispersion or Partial w/ LID features

(when over 50% is lawn) instead of (when over 50% is lawn) instead of Detention facility Detention facility

• Use in Subdivisions being created by Use in Subdivisions being created by Summary PlatSummary Plat

• Use when dividing one parcel into two Use when dividing one parcel into two • Use in small subdivision developments Use in small subdivision developments

where a common area is not feasible and/or where a common area is not feasible and/or HOA will not have the legal or financial HOA will not have the legal or financial ability to maintain a common area with a ability to maintain a common area with a traditional storm water management facility traditional storm water management facility

Ratio for effective impervious Ratio for effective impervious areasareas

% Native Vegetation Preserved

(min. allowed)65

% Effective Impervious

(max. allowed)10

% Lawn/Landscape(max. allowed)

35

60 9 40

55 8.5 45

50 8 50*

45 7 55*

40 6 60*

35 5.5 65*

Infiltration Basin Infiltration Basin RequirementsRequirements• Not applicable in industrial and commercial areas Not applicable in industrial and commercial areas

where solvents, petroleum or pesticides are loaded, where solvents, petroleum or pesticides are loaded, unloaded, stored or appliedunloaded, stored or applied

• Provide data that soils are not >20% clay & <40% Provide data that soils are not >20% clay & <40% silt/clay. Clay soils are not conducive to infiltrationsilt/clay. Clay soils are not conducive to infiltration

• Double-Ring test for infiltration must be perform by Double-Ring test for infiltration must be perform by geotechnical engineering firm and sealed by a PE geotechnical engineering firm and sealed by a PE from that firmfrom that firm

• Infiltration rates must be between .5 & 3 in/hrInfiltration rates must be between .5 & 3 in/hr• Infiltration basins have a high failure rate due to Infiltration basins have a high failure rate due to

improper siting, design and lack of maintenance improper siting, design and lack of maintenance • Must meet all criteria outlined on LDD’S new Must meet all criteria outlined on LDD’S new

checklist checklist

Mechanical Water Quality Mechanical Water Quality Device PolicyDevice Policy

• On current approved list (Appendix G)On current approved list (Appendix G)

• If not, provide the device’s pollutant efficiency If not, provide the device’s pollutant efficiency data approved by EPA ETV or NJCAT programsdata approved by EPA ETV or NJCAT programs

• Use efficiency data as input data for IDEAL to Use efficiency data as input data for IDEAL to prove required removal efficiencies for prove required removal efficiencies for pollutant of concernpollutant of concern

• Devices will be approved on a site by site basis Devices will be approved on a site by site basis with IDEAL’s adequate removal demonstrated with IDEAL’s adequate removal demonstrated

Staff Request for Staff Request for ConsiderationConsideration• 360 map – small scale and color on top of color is 360 map – small scale and color on top of color is

difficult to read (especially yellow & green) difficult to read (especially yellow & green) • Similar line types used on small drawings are Similar line types used on small drawings are

difficult to readdifficult to read• Each firm uses different legends markings for Each firm uses different legends markings for

similar items such as retaining wallssimilar items such as retaining walls• Inspectors rely on the “site map” on plans to find Inspectors rely on the “site map” on plans to find

the site location – please make sure to includethe site location – please make sure to include• Quantities need to be field measured for accuracy Quantities need to be field measured for accuracy

on letters of credit & roadway acceptance on letters of credit & roadway acceptance certificationscertifications

• Stormwater facilities need volume capacity verified Stormwater facilities need volume capacity verified earlier in construction during grading operations earlier in construction during grading operations

Permit Extension Joint Permit Extension Joint Resolution of 2010 (H4445)Resolution of 2010 (H4445)

• For development approval that is For development approval that is current and valid at any point during current and valid at any point during the period beginning January 1, 2008 the period beginning January 1, 2008 and ending December 31, 2012, the and ending December 31, 2012, the running of the period of the running of the period of the development approval and any development approval and any associated vested right is suspended associated vested right is suspended during the period beginning January 1, during the period beginning January 1, 2008 and ending December 31, 2012 2008 and ending December 31, 2012

Grading Permit Renewal Grading Permit Renewal beginning 2013beginning 2013

• July 2012 – Inspection staff will categorize current July 2012 – Inspection staff will categorize current permitted sitespermitted sites– Subdivisions that have reached 50% build out and need Subdivisions that have reached 50% build out and need

certifications and pond acceptance documentscertifications and pond acceptance documents– Subdivisions that need to renew (not 50% yet)Subdivisions that need to renew (not 50% yet)– Sites that are substantially complete, need stabilization Sites that are substantially complete, need stabilization

letter and close out documentsletter and close out documents– Active Sites that need to renewActive Sites that need to renew– Inactive Sites that need to be stabilized and permit Inactive Sites that need to be stabilized and permit

voided voided – Sites that were never started and permit voided Sites that were never started and permit voided – Permitted sites that do not need renewal in the first 6 Permitted sites that do not need renewal in the first 6

months of 2013months of 2013

2012 Permit Renewal 2012 Permit Renewal ProcessProcess• Letters will go out by September giving Letters will go out by September giving

developers 3 months to stabilize & close developers 3 months to stabilize & close based on 50% build out or renew their permits based on 50% build out or renew their permits

• Engineer of Record will be copiedEngineer of Record will be copied

• Unresolved sites compliance will have permits Unresolved sites compliance will have permits revoked, holds placed on building permits and revoked, holds placed on building permits and possible citations and civil penalties possible citations and civil penalties depending on the condition of site depending on the condition of site

SCDHEC’s 2012 General SCDHEC’s 2012 General Construction Permit Construction Permit RequirementsRequirements• The public notice period has closedThe public notice period has closed• Currently being edited based on Currently being edited based on

comments received during notice periodcomments received during notice period• Anticipated date for issuance is this Anticipated date for issuance is this

SpringSpring• LDD Staff is reviewing permit LDD Staff is reviewing permit

application forms, checklists & current application forms, checklists & current procedures for possible changes to procedures for possible changes to meet the new requirements meet the new requirements

SCDHEC’s 2012 General SCDHEC’s 2012 General Construction Permit Construction Permit RequirementsRequirements• Secondary Permittee – Home Builders, Secondary Permittee – Home Builders,

Individual Lot Owners, Contractors and Individual Lot Owners, Contractors and possibly Utility Providerspossibly Utility Providers

• Contractor Certification forms must be on siteContractor Certification forms must be on site• Utility Providers may obtain from DHEC a Utility Providers may obtain from DHEC a

blanket notice of intent blanket notice of intent • Individual Lot NOI will be required (plat, plan Individual Lot NOI will be required (plat, plan

or map needed)or map needed)• Primary’s SWPPP must outline if Secondary Primary’s SWPPP must outline if Secondary

will adhere to the SWPPP or develop their own will adhere to the SWPPP or develop their own

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued

• Ongoing Project (2006 GCP)Ongoing Project (2006 GCP)– May be asked to confirm intent to be May be asked to confirm intent to be

coveredcovered– If requested, must provide w/in 30 daysIf requested, must provide w/in 30 days– If not confirmed coverage is terminatedIf not confirmed coverage is terminated– Must modify current SWPPP to add Must modify current SWPPP to add

Section 3.1.1F no later than 6 month Section 3.1.1F no later than 6 month after new permitafter new permit


• Section 3.1.1 FSection 3.1.1 F– Add appendix for progress reports, compliance Add appendix for progress reports, compliance

and modificationand modification– Revise SWPPP to address non-numeric effluent Revise SWPPP to address non-numeric effluent

limits unless specifically excludedlimits unless specifically excluded– Change frequency of site visits to weeklyChange frequency of site visits to weekly– Add Rain Log appendixAdd Rain Log appendix– Add Inspection Log appendixAdd Inspection Log appendix– Qualified Inspector can not be direct employee Qualified Inspector can not be direct employee

of contractor of contractor


• Ongoing Project (1998 GCP)Ongoing Project (1998 GCP)– Must comply with Section 3.1.1 FMust comply with Section 3.1.1 F– Must have a permanent maintenance Must have a permanent maintenance

agreementagreement

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• New Owners of Previously Permitted SitesNew Owners of Previously Permitted Sites

– Must notify w/in 14 calendar days with project Must notify w/in 14 calendar days with project name, initial permittee NOI tracking numbername, initial permittee NOI tracking number

– If completely stabilized and inactive 14 days If completely stabilized and inactive 14 days does not applydoes not apply

– If inactive but not completely stabilized must If inactive but not completely stabilized must obtain NOI and develop stabilization planobtain NOI and develop stabilization plan

– If complying with existing SWPPP transfer NOIIf complying with existing SWPPP transfer NOI– Completed NOI must come with G’ville Co Completed NOI must come with G’ville Co

approval letter stating that the construction is approval letter stating that the construction is consistent with all requirements of this permit consistent with all requirements of this permit

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• On-site SWPPPOn-site SWPPP

– Living document w/modification and record logsLiving document w/modification and record logs– Kept on-site until final stabilizationKept on-site until final stabilization– Notice on-site of plans location with updated contact info Notice on-site of plans location with updated contact info

posted near main entrance (if no personnel present)posted near main entrance (if no personnel present)– Contractors and Builders w/day to day operations must Contractors and Builders w/day to day operations must

have a copy of the on-site SWPPP at central location by have a copy of the on-site SWPPP at central location by identifying responsibilityidentifying responsibility

– Copy sent to DHEC’s regional office for linear projectsCopy sent to DHEC’s regional office for linear projects– Must be made available upon requestMust be made available upon request– Created after NOI coverage is granted Created after NOI coverage is granted

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• On-Site SWPPP contentsOn-Site SWPPP contents

– Copy of Comprehensive SWPPP (excluding Copy of Comprehensive SWPPP (excluding engineering report)engineering report)

– SCDHEC General Construction PermitSCDHEC General Construction Permit– NOI letter (stamped and approved)NOI letter (stamped and approved)– NPDES Coverage Approval letterNPDES Coverage Approval letter– Local ApprovalLocal Approval– USACOE Approval (if applicable)USACOE Approval (if applicable)– Contractor CertificationsContractor Certifications– Record Keeping (Pre-Con log, Inspection log, Record Keeping (Pre-Con log, Inspection log,

Stabilization log, Rain log & Contractor log)Stabilization log, Rain log & Contractor log)


• Defines Major and Minor ModificationsDefines Major and Minor Modifications– Major (significant changes in design, Major (significant changes in design,

construction, operation or maintenance that construction, operation or maintenance that reasonable potential to cause or contribute reasonable potential to cause or contribute to violations of SC Water Quality standards)to violations of SC Water Quality standards)

– Major changes must go back to regulating Major changes must go back to regulating agency for review and approvalagency for review and approval

– MS4 is given authority to determine if MS4 is given authority to determine if SWPPP is ineffective & that modifications SWPPP is ineffective & that modifications are needed are needed


• Major Modifications include:Major Modifications include:– Resizing sediment/detention basinsResizing sediment/detention basins– Deletion of sediment traps/detention basins Deletion of sediment traps/detention basins – Relocation of sediment traps/detention basinsRelocation of sediment traps/detention basins– Addition of sediment traps/detention basinsAddition of sediment traps/detention basins– Modifications to outlet structures of basinsModifications to outlet structures of basins– Changes in grading that alter drainage patterns Changes in grading that alter drainage patterns

that increase/decrease flow to traps/basinsthat increase/decrease flow to traps/basins– Amending construction sequence that basins Amending construction sequence that basins

are not installed before grubbing operations are not installed before grubbing operations


• Major Modifications involving Point Major Modifications involving Point Discharge or outfall locations changes Discharge or outfall locations changes include:include:– Modifications to regulated WQ structureModifications to regulated WQ structure– Adding new point dischargeAdding new point discharge– Adding impervious or disturbed areaAdding impervious or disturbed area– Navigable water crossing changesNavigable water crossing changes– Site layouts that require redesigning storm water Site layouts that require redesigning storm water

management conveyance systemsmanagement conveyance systems– Adding sediment traps Adding sediment traps


• Minor Modifications (Changes can be Minor Modifications (Changes can be made to on-site SWPPP only)made to on-site SWPPP only)– Adding ECSC BMP’s (if no wetlands Adding ECSC BMP’s (if no wetlands

involved)involved)– Relocating ESSC BMP’sRelocating ESSC BMP’s– Removing disturbed areasRemoving disturbed areas– Individual lot drainage modificationsIndividual lot drainage modifications

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• SWPPP Content – NarrativeSWPPP Content – Narrative

– Scope of Project w/ detailed description pre & Scope of Project w/ detailed description pre & post conditionpost condition

– Description of existing flooding problems on-Description of existing flooding problems on-site or surrounding areassite or surrounding areas

– Required on-site support activities (concrete or Required on-site support activities (concrete or batch plants)batch plants)

– Identification of prior uses of the site, potential Identification of prior uses of the site, potential sources of pollution & how it contributes to WQ sources of pollution & how it contributes to WQ standard violationsstandard violations

– Identify industrial stormwater discharges that Identify industrial stormwater discharges that will be on the sitewill be on the site


• SWPPP ContentsSWPPP Contents– Specifically state that “impervious surfaces for Specifically state that “impervious surfaces for

stabilization should be avoided” as Erosion stabilization should be avoided” as Erosion Prevention BMPPrevention BMP

– Identify and describe measures to prevent the Identify and describe measures to prevent the discharge of building and construction debrisdischarge of building and construction debris

– Identify all potential sources of pollution Identify all potential sources of pollution (sediment, fertilizers, etc)(sediment, fertilizers, etc)

– Detention/Retention Ponds design refer to Detention/Retention Ponds design refer to 72.307 72.307


• SWPPP – Sequence of ConstructionSWPPP – Sequence of Construction– >5 acres must have phased erosion control >5 acres must have phased erosion control

plan for each phase having a specific sequence plan for each phase having a specific sequence of constructionof construction

– Sequence must be include on construction site Sequence must be include on construction site planplan• Must begin w/ construction entrance and perimeter Must begin w/ construction entrance and perimeter

controlcontrol

• End w/ temp sediment & erosion control measuresEnd w/ temp sediment & erosion control measures

• Conversion of BMP to permanent controlConversion of BMP to permanent control

• Level of detail vary based on complexity of project Level of detail vary based on complexity of project

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• SWPPP Content – Sensitive AreasSWPPP Content – Sensitive Areas

– Must identify all Waters of the State, Wetlands Must identify all Waters of the State, Wetlands w/in disturbed areas, total area and if w/in disturbed areas, total area and if immediately adjacent.immediately adjacent.

– Identify receiving watersIdentify receiving waters– Must show all Waters of the State on separate Must show all Waters of the State on separate

plan sheet if w/in construction siteplan sheet if w/in construction site– Must identify all impacted areas by outlining Must identify all impacted areas by outlining

and labeling that no work can begin until COE and labeling that no work can begin until COE &401 obtained&401 obtained

– If structural BMP is proposed w/in Waters of the If structural BMP is proposed w/in Waters of the state must meet section 3.2.6.A.V state must meet section 3.2.6.A.V


• SWPPP – Buffer Zone PreservationSWPPP – Buffer Zone Preservation– When waters of the state are located on or When waters of the state are located on or

immediately adjacent to the construction immediately adjacent to the construction sitesite• Identify and preserve an undisturbed vegetated Identify and preserve an undisturbed vegetated

buffer during constructionbuffer during construction

•30’ Buffer minimum between waters of the state30’ Buffer minimum between waters of the state

•45’ Buffer around high class water or impaired 45’ Buffer around high class water or impaired waterswaters

•Additional local requirements may applyAdditional local requirements may apply


• SWPPP – Buffer Zone PreservationSWPPP – Buffer Zone Preservation– All discharges though the buffer must be All discharges though the buffer must be

non-channelized and/or non-concentratednon-channelized and/or non-concentrated– Must first be treated by the construction Must first be treated by the construction

site’s sediment and erosion controls BMP’ssite’s sediment and erosion controls BMP’s– Special circumstances may allow work in Special circumstances may allow work in

the buffer if all disturbed areas above have the buffer if all disturbed areas above have reached final stabilization and work will not reached final stabilization and work will not cause violation of water quality standards cause violation of water quality standards

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• SWPPP – Buffer Zone PreservationSWPPP – Buffer Zone Preservation

– If buffer is unattainable the SWPPP must identify If buffer is unattainable the SWPPP must identify and require the implementation of sediment and and require the implementation of sediment and erosion control that will prevent the discharge of erosion control that will prevent the discharge of sediment-laden stormwatersediment-laden stormwater

– Must provide a written waiver with justification and Must provide a written waiver with justification and supporting documentationsupporting documentation

– Additional BMP’s that surpasses the regular Additional BMP’s that surpasses the regular standardsstandards

– Maintenance Agreement during construction with Maintenance Agreement during construction with outline of detailed plan for each BMPoutline of detailed plan for each BMP

– Letter from the permitting agency (ie: GC LDD)Letter from the permitting agency (ie: GC LDD)– DHEC must approve all written variance requests DHEC must approve all written variance requests


• SWPPP – Buffer Zone PreservationSWPPP – Buffer Zone Preservation– Certain types of construction activities Certain types of construction activities

are exemptedare exempted• Water, Sewer, Utility, and Roadway construction at Water, Sewer, Utility, and Roadway construction at

water crossingwater crossing

• Construction of water-dependent structures and access Construction of water-dependent structures and access areasareas

• Development of a site where no naturally vegetated Development of a site where no naturally vegetated buffer area existed prior to the construction projectbuffer area existed prior to the construction project

• Construction sites previously covered under 2006 GCPConstruction sites previously covered under 2006 GCP


• SWPPP Content – EPSC BMP’sSWPPP Content – EPSC BMP’s– Accurately and descriptively address the use, Accurately and descriptively address the use,

installation, maintenance and inspection of the installation, maintenance and inspection of the EPSC BMP’sEPSC BMP’s

– Compute only # of acres draining to sediment Compute only # of acres draining to sediment basin that are disturbedbasin that are disturbed

– Use porous baffles in temp. sediment traps and Use porous baffles in temp. sediment traps and sediment basins (unless infeasible)sediment basins (unless infeasible)

– Sediment traps must be used if draining > 2 Sediment traps must be used if draining > 2 acres but < 5 acres acres but < 5 acres


• SWPPP Content – Runoff ControlSWPPP Content – Runoff Control– Permanent Conveyance Measures must Permanent Conveyance Measures must

handle the 10 yr – 24 hr storm and must be handle the 10 yr – 24 hr storm and must be <5 fps. If >5 fps must reduce velocity to <5 fps. If >5 fps must reduce velocity to non-erosive or use liner to reduce erosionnon-erosive or use liner to reduce erosion

– Temporary Conveyance channels must Temporary Conveyance channels must divert concentrated flow of stormwater divert concentrated flow of stormwater running to it, on to the site and stabilize running to it, on to the site and stabilize these w/in 7 days these w/in 7 days


• SWPPP Content – Post Construction WQSWPPP Content – Post Construction WQ– Development condition must not cause or Development condition must not cause or

contribute to violations of WQ standardscontribute to violations of WQ standards– Non-Structural BMP’s must be designed, Non-Structural BMP’s must be designed,

installed and maintained to maximum pollutant installed and maintained to maximum pollutant removalremoval

– LID BMP’s must be installed only after areas LID BMP’s must be installed only after areas are stabilizedare stabilized

– Design, Inspect and maintain BMP’s in SWPPP Design, Inspect and maintain BMP’s in SWPPP at a minimum consistent w/ design manual at a minimum consistent w/ design manual

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• SWPPP – MapsSWPPP – Maps

– Show overlaying contours of the site & surrounding areas on Show overlaying contours of the site & surrounding areas on topo maptopo map

– Include names of each soil types on soil mapInclude names of each soil types on soil map– Each floodplain must be clearly identifiedEach floodplain must be clearly identified– Vicinity map must include a north arrowVicinity map must include a north arrow– Drainage map needed for pre & post developed conditions & Drainage map needed for pre & post developed conditions &

contourscontours– Drainage basins & sub-basins where stormwater runoff collects Drainage basins & sub-basins where stormwater runoff collects

& drains to a common outfall& drains to a common outfall– Include offsite areas draining onto the siteInclude offsite areas draining onto the site– Drainage maps must be consistent w/ the info provide in all Drainage maps must be consistent w/ the info provide in all

calculations provided in the reportcalculations provided in the report– Drainage Map for each BMP to meet WQ (outline drainage Drainage Map for each BMP to meet WQ (outline drainage

basin for proposed BMP’s, location of each proposed BMP & basin for proposed BMP’s, location of each proposed BMP & area in acres to each area in acres to each


• SWPPP Content – Engineering ReportSWPPP Content – Engineering Report– Stable Channel Analysis to ensure non-Stable Channel Analysis to ensure non-

erosiveerosive– Storm Sewer AnalysisStorm Sewer Analysis– Rip Rap Apron AnalysisRip Rap Apron Analysis


• SWPPP – Engineering ReportSWPPP – Engineering Report– Permanent WQ analysis w/ detailed Permanent WQ analysis w/ detailed

calculations for any structural BMPcalculations for any structural BMP– Sedimentology (trapping efficiency Sedimentology (trapping efficiency

analysis) detailed calculations for any analysis) detailed calculations for any BMP used to meet WQ requirementsBMP used to meet WQ requirements

– As-built survey required if directing As-built survey required if directing runoff to a previously approved runoff to a previously approved detention pond unless as-built has been detention pond unless as-built has been provided and accepted provided and accepted


• SWPPP – Detention As-built DataSWPPP – Detention As-built Data– All existing grades/contours/depth of All existing grades/contours/depth of

pondpond– Invert diameters, elevations & Invert diameters, elevations &

dimensions of all outlet structures dimensions of all outlet structures (pipes, orifices, weirs, risers & (pipes, orifices, weirs, risers & emergency spillway)emergency spillway)

– Location & inverts for all pipe Location & inverts for all pipe discharging into the pond discharging into the pond


• SWPPP – Construction PlansSWPPP – Construction Plans– Must be consistent w/ 72-307.A.3Must be consistent w/ 72-307.A.3– Detailed EPSC Plan sheets including, Detailed EPSC Plan sheets including,

grading and drainage plan and BMP grading and drainage plan and BMP detail sheetdetail sheet

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• SWPPP Content – Phased EPSC Plan SWPPP Content – Phased EPSC Plan

– Each Phase must be on a separate plan sheet Each Phase must be on a separate plan sheet and one sheet w/all the detailsand one sheet w/all the details

– Non-linear sites disturbing >10 must have at Non-linear sites disturbing >10 must have at least a 3 phased EPSC planleast a 3 phased EPSC plan• Initial/major gradingInitial/major grading• Construction interim (temp BMP’s to convey, Construction interim (temp BMP’s to convey,

manage, treat)manage, treat)• Final Contours (stabilization plan) Final Contours (stabilization plan)

– Non-linear sites disturbing <10 acres must Non-linear sites disturbing <10 acres must have at least a 2 phased EPSC plan have at least a 2 phased EPSC plan • Initial/major gradingInitial/major grading• Final Contours (stabilization plan)Final Contours (stabilization plan)


• SWPPP – Non-Effluent LimitsSWPPP – Non-Effluent Limits– Control Stormwater volume and velocity Control Stormwater volume and velocity

w/in site to minimize erosionw/in site to minimize erosion•Volume (limit amount disturbed, phasing, Volume (limit amount disturbed, phasing,

terracing, diverting offsite flow, controlling terracing, diverting offsite flow, controlling drainage patterns)drainage patterns)

•Velocity (surfacing roughening, sediment Velocity (surfacing roughening, sediment traps, temp seeding, blankets, TRM, BFM, traps, temp seeding, blankets, TRM, BFM, riprap, polys)riprap, polys)


• SWPPP – Non-Numeric Effluent Limits SWPPP – Non-Numeric Effluent Limits – Control Stormwater discharges to Control Stormwater discharges to

minimize erosion at outlets, downstream minimize erosion at outlets, downstream channels & streambankschannels & streambanks•Volume discharge control (Hydrology, surface Volume discharge control (Hydrology, surface

outlets, WQ storage w/in impoundments)outlets, WQ storage w/in impoundments)

•Peak rate discharge (energy dissipaters, level Peak rate discharge (energy dissipaters, level spreaders, riprap aprons, blankets, TRM) spreaders, riprap aprons, blankets, TRM)


• SWPPP – Non-Effluent LimitsSWPPP – Non-Effluent Limits– Minimize Amount of Soil ExposedMinimize Amount of Soil Exposed

•Phased EPSC plan that limits amount of Phased EPSC plan that limits amount of exposed soilexposed soil

•Outline the limits of disturbance on planOutline the limits of disturbance on plan

•Stabilize exposed area ASAPStabilize exposed area ASAP

• Implement temporary seedingImplement temporary seeding


• SWPPP – Non-Effluent LimitsSWPPP – Non-Effluent Limits– Minimize the disturbance of steep slopes Minimize the disturbance of steep slopes

(15% and greater)(15% and greater)•Divert flow around steep slope disturbanceDivert flow around steep slope disturbance•Use specialized control for steep slopes Use specialized control for steep slopes

(mattings, blankets, pipe slope drains, seep (mattings, blankets, pipe slope drains, seep berms)berms)

•Stabilization ASAP after disturbance (no later Stabilization ASAP after disturbance (no later than 7 days) & w/in 3 working days of than 7 days) & w/in 3 working days of stabilization efforts must have vegetation stabilization efforts must have vegetation cover & installed non-vegetation covercover & installed non-vegetation cover


• SWPPP – Non-Effluent LimitsSWPPP – Non-Effluent Limits– Minimize sediment discharges from the Minimize sediment discharges from the

site during constructionsite during construction– Maintain natural buffers around surface Maintain natural buffers around surface

waterswaters– Direct stormwater to vegetated areas to Direct stormwater to vegetated areas to

maximize infiltration during constructionmaximize infiltration during construction– Minimize soil compaction and preserve Minimize soil compaction and preserve

topsoiltopsoil


• SWPPP – Non-Effluent LimitsSWPPP – Non-Effluent Limits– Stabilize soil w/in a time period as Stabilize soil w/in a time period as

determined by the permitting authority. determined by the permitting authority. Mulch and other temp measures should Mulch and other temp measures should be used when vegetation stabilization in be used when vegetation stabilization in not immediately feasiblenot immediately feasible

– Discharges from dewatering are Discharges from dewatering are prohibited unless managed by prohibited unless managed by appropriate controlsappropriate controls


• SWPPP – Non-Effluent LimitsSWPPP – Non-Effluent Limits– Minimize discharges of pollutants during Minimize discharges of pollutants during

constructionconstruction•Equipment/vehicle washing, wheel washing & Equipment/vehicle washing, wheel washing &

other wash waters (must be treated in a other wash waters (must be treated in a sediment trap)sediment trap)

•Exposure of building material/products, Exposure of building material/products, construction waste, trash, landscape, detergents, construction waste, trash, landscape, detergents, sanitary waste, fertilizers, herbicidessanitary waste, fertilizers, herbicides

•Spill & Leak prevention plan & response Spill & Leak prevention plan & response procedureprocedure


• SWPPP – Non-Effluent LimitsSWPPP – Non-Effluent Limits– Prohibited DischargesProhibited Discharges

•Washout of ConcreteWashout of Concrete

•Washout of paints, oils, stucco, curing Washout of paints, oils, stucco, curing compoundscompounds

•Fuels, oils & other vehicle/equipment Fuels, oils & other vehicle/equipment maintenance materialmaintenance material

•Soaps & solvents in washing Soaps & solvents in washing

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• SWPPP – TMDLSWPPP – TMDL

– If TMDL applicable to stormwater construction If TMDL applicable to stormwater construction discharges have been established in receiving discharges have been established in receiving waters must incorporate measures or controls waters must incorporate measures or controls that are consistent with TMDLthat are consistent with TMDL

– If specific waste load allocation has been If specific waste load allocation has been established to discharge must incorporate that established to discharge must incorporate that allocation into SWPPP (IDEAL)allocation into SWPPP (IDEAL)

– 303(d) for sediment, BIO,TP & TN303(d) for sediment, BIO,TP & TN• Carefully evaluate all selected BMP’s & their Carefully evaluate all selected BMP’s & their

performanceperformance• >25 acres must be a written quantitative and >25 acres must be a written quantitative and

qualitative assessment (IDEAL) qualitative assessment (IDEAL)


• Implementation, Inspection & Implementation, Inspection & MaintenanceMaintenance– Pre-Construction ConferencePre-Construction Conference

•Linear (Stand Alone) Construction ProjectsLinear (Stand Alone) Construction Projects– Can conduct conference offsite w/ each contractorCan conduct conference offsite w/ each contractor

•Non-linear construction disturbing 10 acres Non-linear construction disturbing 10 acres & >& >

– Primary or Secondary Permittee must conduct Primary or Secondary Permittee must conduct conference w/ each contractor or builder who is conference w/ each contractor or builder who is not a permittee on sitenot a permittee on site

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• Implementation, Inspection & Maintenance Implementation, Inspection & Maintenance

– Pre-Con’s PurposePre-Con’s Purpose• Preparing of the SWPPP, Equivalent Registration or Preparing of the SWPPP, Equivalent Registration or

the Person w/ operational control of the plans to the Person w/ operational control of the plans to explain the entire SWPPP to the contractors & explain the entire SWPPP to the contractors & buildersbuilders

• Specifically go over the areas of the SWPPP that Specifically go over the areas of the SWPPP that relates to the work performed by themrelates to the work performed by them

• Must address how modifications (major/minor) to the Must address how modifications (major/minor) to the plans will be addressed and processed at the plans will be addressed and processed at the construction site to maintain complianceconstruction site to maintain compliance

• Meeting must be documented w/in the On-Site Meeting must be documented w/in the On-Site SWPPP (dates, locations, times, attendance)SWPPP (dates, locations, times, attendance)

• Document meeting to complete contractor Document meeting to complete contractor certification form certification form

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• Inspections Inspections

– Scope (all disturbed areas, perimeter BMP, exposed material Scope (all disturbed areas, perimeter BMP, exposed material storage areas, evidence of potential pollutants entering storage areas, evidence of potential pollutants entering conveyance system, discharge locations, EPSC measures, conveyance system, discharge locations, EPSC measures, vehicle access point, inefficiencies w/in BMP’s)vehicle access point, inefficiencies w/in BMP’s)

– Frequency (minimum once every week, once finally stabilized Frequency (minimum once every week, once finally stabilized definable area can be marked off on-site SWPPP)definable area can be marked off on-site SWPPP)

– Rain Gauge (maintain on-site gauge or use data from certified Rain Gauge (maintain on-site gauge or use data from certified weather record w/in reasonable proximity, record rainfall weather record w/in reasonable proximity, record rainfall events .5” &>, must maintain in rain log in on-site SWPPP)events .5” &>, must maintain in rain log in on-site SWPPP)

– Inspector Qualifications (can not be a direct employee of any Inspector Qualifications (can not be a direct employee of any contractor responsible for activity covered by the inspector, for contractor responsible for activity covered by the inspector, for projects > 2 acres, for 2 acres & < permittee may perform projects > 2 acres, for 2 acres & < permittee may perform inspections provided the preparer of SWPPP explains the inspections provided the preparer of SWPPP explains the SWPPP implementation & inspection requirements)SWPPP implementation & inspection requirements)

– Monthly Reports (DHEC may require on case-by-case basis Monthly Reports (DHEC may require on case-by-case basis submitted monthly reports) submitted monthly reports)


• MaintenanceMaintenance– Permittee must address the necessary Permittee must address the necessary

replacement or modification required to correct replacement or modification required to correct BMP w/in 48 hrs of identificationBMP w/in 48 hrs of identification

– Sediment must be removed when deposited Sediment must be removed when deposited sediment reaches 1/3 height of the BMPsediment reaches 1/3 height of the BMP

– A detailed permanent maintenance plan must A detailed permanent maintenance plan must be outlined in the narrativebe outlined in the narrative

– Agreement and maintenance plan must be in Agreement and maintenance plan must be in the SWPPP the SWPPP


• Maintenance AgreementsMaintenance Agreements– Signed notarized agreement from Signed notarized agreement from

responsible party for each of the responsible party for each of the permanent WQ featurespermanent WQ features

– MS4 must be notified in writing of any MS4 must be notified in writing of any changes in the maintenance responsibilitieschanges in the maintenance responsibilities

– Construction sites originally permitted Construction sites originally permitted under 1998 GCP must sign notarized under 1998 GCP must sign notarized maintenance agreement maintenance agreement

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• Secondary Permittees are responsible for Secondary Permittees are responsible for

either maintaining or coordinating the either maintaining or coordinating the maintenance of Common BMP’s which maintenance of Common BMP’s which accept storm water discharge from any accept storm water discharge from any areas associated with their work with the areas associated with their work with the Primary permittee Primary permittee

• Maintenance Plans ContentMaintenance Plans Content– Description of maintenance plan usedDescription of maintenance plan used– Manufactured devices must have detailed Manufactured devices must have detailed

procedures for maintenance included in planprocedures for maintenance included in plan– Each WQ feature must have maintenance Each WQ feature must have maintenance

activity described for all items of featureactivity described for all items of feature


• Termination of Coverage (NOT)Termination of Coverage (NOT)– Can submit only if one or more below existCan submit only if one or more below exist

• Final stabilization has been achieved on all portions Final stabilization has been achieved on all portions of the site for which permittee is responsibleof the site for which permittee is responsible

• Another operator has assumed control over all areas Another operator has assumed control over all areas not finally stabilizednot finally stabilized

• Individual Lot Coverage or Alternate General NPDES Individual Lot Coverage or Alternate General NPDES permit has been obtainedpermit has been obtained

• For residential subdivision lot temp stabilized and lot For residential subdivision lot temp stabilized and lot ownership transferred to homeownerownership transferred to homeowner

• Land disturbance was never initiated on the site and Land disturbance was never initiated on the site and the site remains permanently stabilized the site remains permanently stabilized

General Construction Permit General Construction Permit Requirements ContinuedRequirements Continued• Notice of Termination (NOT)Notice of Termination (NOT)

– DHEC must receive letter from MS4 that site DHEC must receive letter from MS4 that site meets criteria to terminate permitmeets criteria to terminate permit

– If ownership or maintenance of permanent WQ If ownership or maintenance of permanent WQ features have change since original approval features have change since original approval copy of revised agreement must be attachedcopy of revised agreement must be attached

– Primary Permittee’s in residential subdivisions Primary Permittee’s in residential subdivisions can request NOT when Secondary Permittees can request NOT when Secondary Permittees are authorized to conduct construction are authorized to conduct construction activities for the remaining disturbed areas of activities for the remaining disturbed areas of the construction site and final stabilization has the construction site and final stabilization has been achieved on all other area of the site. been achieved on all other area of the site.

EPA’s Permit RequirementsEPA’s Permit Requirements

• Stormwater RegulationsStormwater Regulations– Original Deadline was September 30, 2011Original Deadline was September 30, 2011– Extended to December 30, 2011Extended to December 30, 2011– Negotiating with Chesapeake Bay Foundation Negotiating with Chesapeake Bay Foundation

due to lawsuit filed & current delaysdue to lawsuit filed & current delays– Additional cost-benefit data needAdditional cost-benefit data need– Proposed regulations new date for release is Proposed regulations new date for release is

December 2012/Janaury 2013December 2012/Janaury 2013– New deadline for implementation later in 2013New deadline for implementation later in 2013

EPA’s Permit RequirementsEPA’s Permit Requirements

• National Effluent Standards (Turbidity)National Effluent Standards (Turbidity)– Deadline delayed to obtain better scientific Deadline delayed to obtain better scientific

datadata– January 3, 2012 notice requesting more dataJanuary 3, 2012 notice requesting more data

•Effectiveness of technologies in controlling Effectiveness of technologies in controlling turbidityturbidity

•Seeks comments on passive treatment data Seeks comments on passive treatment data already availablealready available

•Dr. Barfield to summarize research Dr. Barfield to summarize research authorized last year by Greenville Countyauthorized last year by Greenville County

•60 day comment period established for this 60 day comment period established for this requestrequest

SCDHEC’s Permit RenewalsSCDHEC’s Permit Renewals

• DHEC was waiting for the new EPA DHEC was waiting for the new EPA proposed regulations to ensure proposed regulations to ensure Phase II permit regulations were “in Phase II permit regulations were “in line” with new standardsline” with new standards

• With EPA’s delay until 2013 it is With EPA’s delay until 2013 it is believed that DHEC will go ahead and believed that DHEC will go ahead and issue both Phase I and Phase II issue both Phase I and Phase II renewal permits renewal permits

Greenville County’s 3Greenville County’s 3rdrd Cycle CycleNPDES Phase I MS4 PermitNPDES Phase I MS4 Permit

• Our current MS4 permit expires July Our current MS4 permit expires July 1, 20121, 2012

• We submitted our renewal permit We submitted our renewal permit application on December 29, 2011application on December 29, 2011

• Some changes expected in our Some changes expected in our permit requirementspermit requirements

• Increased compliance for watersheds Increased compliance for watersheds with TMDL designations with TMDL designations

Possible requirement Possible requirement changeschanges• Review of local codes and land Review of local codes and land

development requirements to reduce development requirements to reduce storm water impacts of new development storm water impacts of new development and significant redevelopmentand significant redevelopment– Mandate LID principals in specific Mandate LID principals in specific

applications applications – Reduction in impervious surfacesReduction in impervious surfaces– Reduction of flow and volumeReduction of flow and volume– Increase or mimic natural hydrology Increase or mimic natural hydrology

303(d) and TMDL 303(d) and TMDL ComplianceCompliance• Engineer will need to use IDEAL to model Engineer will need to use IDEAL to model

pre and post construction water quality for pre and post construction water quality for identified pollutant for numeric identified pollutant for numeric quantification. quantification.

• For TMDL watersheds with waste load For TMDL watersheds with waste load allocation percentage reduction allocation percentage reduction requirements the site will need to be requirements the site will need to be designed to show in IDEAL that the designed to show in IDEAL that the percentage reduction was achieved on site percentage reduction was achieved on site

Reedy River Nutrient TMDLReedy River Nutrient TMDL

• Will required the pre and post construction Will required the pre and post construction IDEAL model runsIDEAL model runs

• May require use of Green Infrastructure or May require use of Green Infrastructure or disturbance thresholdsdisturbance thresholds

• May require more stringent buffer widths and May require more stringent buffer widths and requirementsrequirements

• May require stream stabilization or restoring May require stream stabilization or restoring buffers in conjunction with site improvementsbuffers in conjunction with site improvements

• Increased education of HOA and in common Increased education of HOA and in common areas on pet waste & maintaining areas on pet waste & maintaining buffers/LID’s buffers/LID’s

Thank You for your Thank You for your AttendanceAttendance

Questions?Questions?

land development division engineer forum february 23, 2012 conference room d

Documents

plans plans

wetlands waters

sealed plans

state delineation

construction site plans

npdes ms4 permit slide

impaired waters

indepth audit