NEW CASTLE CONSERVATION DISTRICT. through. (Name of Municipality) PLAN REVIEW APPLICATION DRAINAGE, STORMWATER MANAGEMENT, EROSION & SEDIMENT CONTROL

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1 NEW CASTLE CONSERVATION DISTRICT through (Name of Municipality) PLAN REVIEW APPLICATION DRAINAGE, STORMWATER MANAGEMENT, EROSION & SEDIMENT CONTROL Office use only: Received by Municipality: Received by District: Review Completed by District: Received by Municipality: Returned to Applicant: New Castle Conservation District is the designated agent of the municipality to accomplish the required plan review. No land disturbing activity can take place on the proposed work site until an Application is prepared the Application components approved by the District in accordance with the Delaware Sediment and Stormwater Regulations adopted January 23, 1991, and the approval is received or picked up by the Applicant. The attached checklist for submission, design and plan requirements must be completed and included in the application package submitted to the municipality. District Address: Contact Person: New Castle Conservation District 2430 Old County Road Newark, Delaware Kevin Donnelly 302/ NPDES Permit #, if any, applicable to any part of the proposed project site Name of proposed project Tax Parcel # Project Size (acres). Landowner: Address: Contact Person: Phone Number: Clearing operations and land disturbing activity for this project must be under the control of a person trained and certified by DNREC (Department of Natural Resources and Environmental Control). Name of Control Person: Certificate #

2 Page 2 of Application - NCCD 1/92 Submission package; Indicate included items on checklist. List applicable section of DNREC Regulations when waiver is being requested. a. Completed Checklist b. Stormwater Management Drainage Computation & Reports Waiver Basis c. Drainage & Stormwater Management Plan d. Erosion & Sediment Control Plan e. Erosion & Sediment Narrative Waiver Basis Application Review Fee; (Calculated on one acre increments) $ per disturbed acre x acres = $ Total Fee: Minimum Fee: $ Review fee will be paid to New Castle Conservation District by check. (Bank Check # ) Individual preparing plans/reports Engineer Surveyor I,, have prepared and submitted the above items in consideration of current practices and state of the art. They are intended and expected to meet all requirements to produce a working system when placed on the site. Adequate borings have been made and analyzed. Developer/owner shall be responsible for maintenance performance during construction and after occupancy. Signature of Engineer/Surveyor Seal: (Name typed/printed) Firm or Company Phone Number

3 Page 3 of Application - NCCD 1/92 Developer: Name of Firm Address: Contact Person: Phone Number: The developer acknowledges responsibility for ensuring that measures placed on the ground perform properly. Upon notification by the Conservation District that this is not the case, he shall ensure corrective action is taken. Further, responsibility for maintaining these measures from initial land disturbing action until final acceptance by the Conservation District is inherent in any submission approval granted. Signature Name typed

4 Page 4 of Application - NCCD 1/92 NEW CASTLE CONSERVATION DISTRICT DRAINAGE, STORMWATER MANAGEMENT, AND EROSION CONTROL CHECKLIST ALL ITEMS ON THIS CHECKLIST MUST BE ADDRESSED AS PART OF THE SUBMISSION Submission Requirements: 1. Completed application form. Copy of checklist with all items addressed. Fees (as required) Two (2) sets of plans (on 24" x 36" sheets maximum) Upon approval, (4) sets of plans must be submitted 1 file 1 applicant 1 on site 1 inspector Erosion and Sediment Control Narrative (include construction schedule) Design Data Design Requirements; (Based on Delaware Sediment & Stormwater Regulations dated January 23, 1991) 2.. All hydraulic computations shall be accomplished using the most recent version of U.S.D.A., Soil Conservation Service TR-20 or TR-55. The storm duration for computational purposes shall be the 24 hour rainfall event. For projects south of the C and D Canal, the Delmarva Unit Hydrograph shall be used. The predevelopment peak discharge rate shall be computed assuming that all land uses in the site to be developed are in good condition. 3. All ponds constructed for stormwater management shall be designed and constructed in accordance with U.S.D.A., Soil Conservation Service Small Pond Code 378, dated September 1990, as approved for use in Delaware. 4. Water quality ponds having a permanent pool shall be designed to release the first 1/2 inch of runoff from the site over a 24 hour period. Water quality ponds not having a permanent pool shall be designed to release the first inch of runoff from the site over a 24 hour period. 5. Post-development peak rates of discharge for the two (2) year and the ten (10) year (and the 100 year frequency storm events for project in New Castle County north of the C and D Canal) shall not exceed the pre-development peak rates of discharge for the two (2) year and the ten (10) year (and the 100 year frequency storm events for projects in New Castle County north of the C and D Canal) frequency storm events.

5 Page 5 of Application - NCCD 1/92 6. Infiltration practices, when used, shall be designed to accept, at least, the first inch of runoff from all streets, roadways, and parking lots (including all contributing drainage areas) and be accompanied by a maintenance schedule with means for certifying maintenance performance. 7. All stormwater design shall be in accordance with the Delaware Sediment and Stormwater Regulations, January Maintenance set aside areas for disposal of sediments removed from stormwater management facilities must be provided. Set aside areas shall accommodate at least 2% of the stormwater management facility volume to the 2 year storage volume elevation, maximum depth of the set aside volume shall be one foot, and the slope of the set aside area shall not exceed 5%. Proper access must be provided for maintenance. 9. All Ponds shall have a forbay or other design feature to act as a sediment trap, a ten (10) foot reverse slope bench must be provided one foot above the normal pool elevation for safety purposes, a ten (10) foot level bench one foot below the normal pool elevation, and all embankment ponds having a permanent pool shall have a drain installed. 10. Infiltration practices shall be used only when the following criteria can be met or exceeded: a. Areas draining to these practices must be stabilized and vegetative filters established prior to runoff entering the system. b. A suspended solids filter accompanies the practice; when vegetation is used, there shall be at least a 20 foot length of vegetative filter. c. The bottom of the infiltration practice is at least three feet above the seasonal high water table. d. The infiltration practice shall be designed to drain completely within 48 hours. e. Infiltration practices are limited to soils having an infiltration rate of at least 1.02 inches per hour. On site soil borings and textural classifications must be done to verify site conditions and seasonal high water table, and this information must be submitted with the plan. f. Infiltration practices greater than three feet deep shall be located at least 20 feet from basement walls. g. Infiltration practices designed to handle runoff from impervious parking areas shall be a minimum of 150 feet from any public or private water supply well.

6 Page 6 of Application - NCCD 1/92 h. Infiltration practices shall have overflow systems with measures to provide a nonerosive velocity of flow along its length and at the outfall. i. The slope of the bottom of the infiltration practice shall not exceed five percent. j. Infiltration practices shall not be installed on or atop a slope whose natural angle of incline exceeds 20%. k. Infiltration practices shall not be installed in fill material. 1. Unless allowed on a specific project, infiltration practices will only be permitted for the primary purpose of water quality enhancement. 11. Minimum grades: 1% in pervious areas 1/2% in impervious areas. 12. Provide soils mapping on plan with a general description of each soil. Mapping shall comply with Soil Conservation Service Standards. 13. Sub-watershed areas must be delineated on the plan for both the pre- and post-development conditions. Provide the area in acres of each sub watershed. 14. Show drainage calculations considering off-site contributing drainage. Provide pre- and post development velocities, peak rates of discharge, and inflow and outflow hydrographs of stormwater runoff at all existing and proposed points of discharge from the site for the two (2) year and the ten (10) year (and the 100 year frequency storm for projects in New Castle County north of the Chesapeake and Delaware Canal) frequency storm. Show site conditions around points of all surface water discharge including vegetation and method of flow conveyance from the land disturbing activity and design details for structural controls. 15. Computations for sizing, culverts, pipes, ditches, and swales. Plan Requirements: 16. An index plan shall be provided with the following information: a. Plan view of entire site at a reasonable scale showing limits of disturbance, limits of wetlands, limits of the 100 year floodplain, project phasing and north arrow. b. Vicinity Map - maximum scale 1"=800. Include road identification and enough detail to locate site. c. Index of sheets d. An owner's certification, "I, the undersigned, certify that all land clearing, construction, and development shall be pursuant to the approved plan and that responsible personnel involved will have a certificate of training from DNREC.

7 Page 7 of Application - NCCD 1/92 DNREC, NCC, and NCCD personnel shall have the right to conduct on-site inspections". (Must be signed in ink on each plan submitted. Include name, address, and telephone number.) e. Specify whose responsibility it will be to repair erosion and sediment controls and stormwater management practices during utility construction. f. General notes. g. Erosion and Sediment Control Legend. h. Provide a site specific, detailed construction sequence including the following activities: clearing and grubbing for those areas necessary for the installation of perimeter control, construction of perimeter controls, remaining clearing and grubbing, road grading, grading for the remainder of the site, utility installation and whether storm drains are to be blocked until site stabilization, final grading, temporary and permanent stabilization (with fertilization, seeding and mulching instructions) and final removal of sediment control practices. 17. Provide a north arrow on all sheets. 18. Maximum plan scale of 1"= 40' 19. Provide existing and proposed contours based on mean sea level datum at minimum 2- foot intervals. However, 1-foot intervals are mandated when slope is less than 5 percent. 20. Wetlands must be delineated and shown on the plan. Delineation must follow Federal Manual currently approved by U.S. Army Corps of Engineers. 21. The National Flood Insurance Rate Map 100 Year Flood Zone must be delineated and shown on the plan. 22. Provide directional stormwater flow arrows for all existing and proposed channels, pipes, etc. 23. Streams must be delineated and shown on plan. 24. All sediment and stormwater management practices must be located on the plan. 25. Provide details and specifications for all erosion and sediment control management practices used. 26. Provide details, cross-sections and specifications (including stabilization) for diversions, ditches, ponds, swales, infiltration structures, etc. 27. Provide details or temporary and permanent stabilization measures including placement of the following statement on all plans, "Following soil disturbance or redisturbance, permanent or temporary stabilization shall be completed within 14 calendar days as to the surface of all perimeter sediment controls, topsoil stockpiles, and all other disturbed or graded areas on the project site".

8 Page 8 of Application - NCCD 1/ Stone check dams are required in all swales, ditches, and channels. Provide details, crosssections and specifications, including check dam station locations. Check dam depth must be such that a maximum stone depth is achieved while ensuring that flow continues over the center of the dam. A minimum 6" depth from the weir to the top of the structure is required. 29. All stone, with the exception of check dams, must be underlined by a filter fabric. Filter fabric specifications must be provided for various applications. 30. Outlet protection is required at all points of discharge from pipes, channels and spillways. Provide details, velocities, flows, cross-sections and specifications, including d50 stone size, stone depth, outlet dimensions and type of filter fabric. 31. Provide inlet and outlet invert elevations for all drainage structures and facilities. 32. Erosion control matting is required on slopes of 3:1 or greater (specify type of matting). 33. Provide corner and lowest floor elevations for all buildings. 34. Specify what stabilization measures shall be initiated if dust control becomes a problem. 35. Sediment traps and basins shall be utilized and sized to accommodate 3600 cubic feet of storage per acre of contributing drainage area until project stabilization is complete. These structures must be located at the base of the drainage area. The following information is required; top of slope elevation, bottom elevation, outlet elevation, dimensions, proposed volume, required volume, type or trap or basin, and contributing drainage area. Include details, cross-sections and specifications; a minimum 2:1 length to width ratio is required. All traps and basins must be numbered for identification. 36. Soil stockpile area must be delineated. Locate stockpiles on areas with little or no slope. Stockpiles must be surrounded with silt fence or a stabilized earthen berm. 37. Provide the volume of any soil or borrow material. Off-site borrow or spoil areas must have an approved and active erosion and sediment control plan. 38. Top, invert in and invert out elevations on all catch basins or junction boxes. 39. Size, type, and length of all drainage pipes.