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SEDIMENT CONTROL MEASURES:CONSTRUCTION NOTES:EROSION PREVENTION MEASURES:DEWATERING AND BASIN DRAINING:INSPECTION AND MAINTENANCE REQUIREMENTS MUST INCLUDE:MAINTENANCE PERFORMANCE:POLLUTION PREVENTION MANAGEMENT:DISCHARGE TO WETLANDS:FINAL STABILIZATION:STORM WATER POLLUTION PREVENTION PLAN (SWPPP)1.The Permittee(s) (either the owner or operator, whoever is identified in the SWPPP) must routinely inspect the entireconstruction site at least once every seven (7) days during active construction and within 24 hours after a rainfallevent greater than 0.5 inches in 24 hours. - Date and time of inspections. All inspections and maintenance conducted during construction shall be recorded within 24 hours in writing and these records must be retained in the SWPPP - Name of person(s) conducting inspections. - Findings of inspections, including specific locations where there are recommendations for corrective actions. - Corrective actions taken (including dates, times, and party completing maintenance activities). - Date and amount of all rainfall events greater than 1/2 inch (0.5 inches) in 24 hours. Rainfall amounts must be obtained by a properly maintained rain gauge onsite, a weather station within 1 mile of the project location, or a weather reporting system that provides site specific rainfall data from radar summaries. - See permit Part 6.1-6.4 for amendments to SWPPP. - Construction site vehicle exit locations must be inspected for evidence of off-site sediment tracking onto paved surfaces. Tracked sediment must be removed from all paved surfaces within 24 hours of discovery (NPDES CSW Permit Part 9.12). - Infiltration and Bioretention facility must be inspected for sedimentation. - Discharges discovered during inspections shall be documented per NPDES CSW Permit part 11.11.f 1. All nonfunctional BMPs must be repaired, replaced, or supplemented with functional BMPs by the end of the next business dayafterdiscovery, or as soon as field conditions allow access unless another time frame is specified that is not less restrictivethan permit requirements. See permit Part 11.4 for specific requirements.2.Perimeter control devices must be repaired, replaced, or supplemented when nonfunctional or sediment reaches on-half the height ofthe device.3.Temporary and permanent sediment basins must be drained and sediment removed when the depth of sediment collected reacheson-half storage volume4.All sediment deposits and deltas must be removed from surface waters (including drainage ways, catch basins, and other drainagesystems) and the removal areas restabilized within 7 days.5.Permanent stormwater treatment BMPs must be inspected and maintained per NPDES CSW Permit 11.31. Solid Waste: Sediment, asphalt and concrete millings, floating debris, paper, plastic, fabric, construction anddemolition debris and other wastes must be properly collected, stored, and disposed of in accordance with Minn. R.ch.7035.This includes any materials used for erosion control. 2. Hazardous and Toxic Materials: Includes, but is not limited to: Oil, gasoline, paint and any hazardous substances must beproperly stored, including secondary containment, to prevent spills, leaks or other discharge. Restricted access to storageareas must be provided to prevent vandalism. Storage and disposal of hazardous waste must be in accordance with Minn.R.Ch.7045 3. External washing of trucks and other construction vehicles must be limited to a defined area of the site. Runoff must becontained and waste properly disposed of. 4. No engine degreasing is allowed on site. 5. Concrete washout onsite: All liquid and solid wastes generated by concrete washout operations must be contained in aleak-proof containment facility or impermeable liner. A compacted clay liner that does not allow washout liquids to enterground water is considered an impermeable liner. The liquid and solid wastes must not contact the ground, and there mustnot be runoff from the concrete washout operations or areas. Liquid and solid wastes must be disposed of properly and incompliance with MPCA regulations. A sign must be installed adjacent to each washout facility to inform concrete equipmentoperators to utilize the proper facilities.6.Building products that have the potential to leach pollutants must be under cover. (NPDES CSW Permit Part 12.2)7.Pesticides, herbicides, insecticides, fertilizers, treatment chemicals, and landscaped materials must be under cover.(NPDES Permit Part 12.3).8.Portable toilets must be positioned so that they are secure and will no be tipped or knocked over. Sanitary waste must be disposedof properly in accordance with Minn.R.ch.7041. (NPDES CSW Permit Part 12.6)9.Spill Prevention and Response Requirements: Adequate supplies must be available at all times to clean up discharged materials andan appropriate method must be available for recovered spilled materials. Spills must be reported and cleaned up immediately asrequired by Minn. Stat. 115.061 using dry cleanup measures where possible.TRAINING REQUIREMENTS:Construction shall be in accordance with the MPCA NPDES General Stormwater Permit for construction activity, plans,Mn/DOT Spec. Book, Standard Specifications for Construction and the special provisions.The Contractor shall maintain a stockpile of erosion control devices at all times for immediate usage.The Contractor shall keep the inspection and maintenance log.See permit Part 20 for SWPPP record retention requirements. SWPPP must be kept on site during construction by permittee who hasoperational control of that portion of the site.In the event of accidental sediment or pollutant discharge, the City, MPCA local contact and/or State Duty Officer shall benotified. The MPCA State Duty Officer can be reached at (800) 422-0798. 1. The Permittee(s) shall ensure the individuals identified in this part have been trained in accordance with the NPDES CSW Permit's training requirements. The Permittee(s) shall ensure the training is recorded in or with the SWPPP before the start of construction or as soon as the personnel for the project have been determined. a. Who must be trained: i. Individual(s) preparing the SWPPP for the project. ii. Individual(s) overseeing implementation of, revising, and amending the SWPPP and individual(s) performing inspections. One of these individual(s) must be available for an on site inspection within 72 hours upon request by the MPCA. iii. Individual(s) performing or supervising the installation, maintenance, and repair of BMPs. At least one individual on a project must be trained in these job duties. b. Training content. The content and extent of training must be commensurate with the individual's job duties and responsibilities with regard to activities covered under this permit for the project. At least one individual present on the permitted project site (or available to the project site in 72 hours) must be trained in the job duties described in Permit Part 20. c. Training documentation: i. Documentation must be recorded with the SWPPP prior to the start of construction. ii. Names of the personnel associated with this project that are required to be trained per Part III.F of this permit. iii. Dates of training and name of instructor(s) and entity providing training. iv. Content of training course or workshop (including number of hours of training). d. The Permittee(s) shall ensure that the individuals are trained by local, state, federal agencies, professional organizations, or other entities with expertise in erosion prevention, sediment control or permanent stormwater management such as the University of Minnesota, Minnesota Erosion Control Association, Soil and Water Conservation Districts or the MPCA. 1. Temporary or permanent stabilization of exposed soils, including stockpiles, shall be initiated immediately to limit soil erosion whenever any construction activity has temporarily or permanently ceased on that portion of the site and will notresume for a period exceeding 7 calendar days. (Permit Part 8.4 and 23.9).2.The normal wetted perimeter of any temporary or permanent drainage ditch or swale that drains water for any portion ofthe construction site, within 200 lineal feet, must be completed within 24 hours after connecting to a surface water orproperty edge. Mulch, hydromulch, tackifier, polyacrylamide, or similar practice is not acceptable stabilization in anypart of a drainage ditch or swale with continuous slop greater than 2%. (Permit Part 8.6-8.8).3.Use check dams along length of conveyance channels. (Permit Part 8.7).4.Temporary or permanent energy dissipation devices must be installed at pipe outlets within 24 hours after connection to asurface water.5. Temporary or permanent ditches or swales that are being used as a sediment containment system during construction must bestabilized within 24 hours after no longer being used as a sediment containment system. 1. In order to maintain sheet flow and minimize rills and/or gullies, there shall be no unbroken slope length of greaterthan 75 feet for slopes with a grade of 1:3 or steeper. 2. Sediment control practices must be established on all down gradient perimeters and upgradient of any buffer zones. Thesepractices shall remiain in place until final stabilization has been achieved and the Permit NOT form has been submitted to the MPCA. 3. Temporary soil stockpiles must have silt fence or other effective sediment controls, and cannot be placed in surfacewaters, including stormwater conveyances such as curb and gutter systems, or conduits and ditches unless there isa bypass in place for the stormwater.4.Vehicle tracking of sediment from the construction site (or onto streets within the site) must be minimized byBest Management Practices (BMPs) such as stone pads, concrete or steel wash racks, or equivalent systems. Trackedsediment onto paved surfaces must be removed daily, at minimum.5.Per Part 9.3, if down gradient sediment controls are overloaded, additional upgradient sediment control practicesor redundant BMPs to eliminate overloading must be installed, and the SWPPP must be amended.6.See permit 9.6 and Part 11 for instructions on re-installation of sediment control practices after they've been adjusted.7.See permit Part 9.7 and 9.8 for instructions on the removal of storm drain inlet protection BMPs.8.Direct discharges from BMPs to vegetated areas, unless infeasible.1. If dewatering is required on the site, there must be a plan in place to prevent nuisance conditions, erosion and inundation of wetlands.2. If using filters with backwash water, backwash water must be hauled away for disposal, returned to the beginning of the treatment process, or incorporated into the site in a manner that does not erode into runoff.1.Permanent stabilization of exposed soils, including stockpiles, shall be initiated immediately to limit soil erosion whenever any construction activity has permanently ceased on any portion of the site and will not resume for a period exceeding 7 calendar days.2.The permanent stormwater treatment system must be constructed, meet all requirements, and operating as designed.3.All sediment must be removed from permanent stormwater management system and conveyance systems.4.All temporary synthetic erosion prevention and and sediment control BMPs must be removed.5. See Landscape sheets for turf establishment.6. Final stabilization is achieved by a uniform perennial vegetative cover with a density of 70% of expected growth over the entirepervious area.2.If there is a wetland impact caused by filling, draining, excavation or inundation, how has that impact been addressed bypermits or other approvals from an official statewide program (U.S. Army Corps of Engineers 404 program, MinnesotaDepartment of Natural Resources, or the State of Minnesota Wetland Conservation Act)? If the impact is consideredexempted or non jurisdictional by theses programs, how is the impact in conformance with the sequence mitigationrequirements of MPCA water quality standards in MN Rule 7050.0186<https://www.revisor.leg.state.mn.us/rules/?id=7050.0186>1.Conventional erosion and sediment control to be used. If neccessary to use chemical treatment, permittee must follow guidelines asstated in NPDES Permit Part 9.182.No Site assessment for groundwater or soil contamination required.THE DESCRIPTION OF INSPECTIONS AND MAINTENANCE:MISCELLANEOUS:BLOCH ENGINEERING, PLLCblochengineering.com32210 XEON ST NWCAMBRIDGE, MN 55008krystle@blochengineering.comNCHBLENGINEERING
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