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JAVELINDISCUS-HAMMERTHROW EVENTEXISTINGBROOMBALLAREASHOTPUT (2)1C2.12C2.1REROSION ANDSEDIMENT CONTROLPLAN - THROWS025 501. REFER TO SHEET C1.4, GRADING AND DRAINAGE PLAN, FOR GENERAL NOTES.2. REFER TO SWPPP NARRATIVE (SECTION 01 89 13) FOR CONSTRUCTION SEQUENCING AND EROSION CONTROL REQUIREMENTS.3. MAINTAIN ADJACENT PROPERTY AND PUBLIC STREETS CLEAN FROM CONSTRUCTION CAUSED DIRT AND DEBRIS ON A DAILY BASIS.PROTECT DRAINAGE SYSTEMS FROM SEDIMENTATION AS A RESULT OF CONSTRUCTION RELATED DIRT AND DEBRIS.4. MAINTAIN DUST CONTROL DURING GRADING OPERATIONS.5. ALL EROSION CONTROL METHODS SHALL COMPLY WITH MPCA AND OTHER LOCAL REGULATIONS.6. IF EROSION AND SEDIMENT CONTROL MEASURES TAKEN ARE NOT ADEQUATE AND RESULT IN DOWNSTREAM SEDIMENT, THECONTRACTOR SHALL BE RESPONSIBLE FOR CLEANING OUT DOWNSTREAM STORM SEWERS AS NECESSARY, INCLUDING ASSOCIATEDRESTORATION.7. PRIOR TO CONSTRUCTION, DELINEATE TURF AND VEGETATED AREAS NOT TO BE DISTURBED WITH ORANGE SNOW FENCE. NOCONSTRUCTION TRAFFIC, EQUIPMENT OR MATERIALS SHALL BE PERMITTED TO UTILIZE, ACCESS, OR OTHERWISE ENTER THE AREASDESIGNATED NOT TO BE DISTURBED. MINIMIZE SOIL COMPACTION AND DISRUPTION OF TOPSOIL IN AREAS OUTSIDE THE CONSTRUCTIONLIMITS TO COMPLY WITH MN CONSTRUCTION STORMWATER GENERAL PERMIT.NOTESSILT FENCE = 400 L.F.ROCK CONSTRUCTION ENTRANCE = 25 C.Y.APPROXIMATE EROSION CONTROL DEVICEQUANTITIESLEGENDREFERENCE KEY TO SITE DETAILS DETAIL I.D NUMBER (TOP) DETAIL SHEET NUMBER (BOTTOM)EXISTING CONTOUREXISTING SPOT ELEVATIONPROPOSED CONTOURPROPOSED SPOT ELEVATIONME = MATCH EXISTINGEOF = EMERGENCY OVERFLOWTW = FINISH GRADE AT HIGH SIDE OF WALLBW = FINISH GRADE AT LOW SIDE OF WALLPROPOSED GRADING LIMITSPROPOSED SILT FENCEPROPOSED ROCK CONSTRUCTION ENTRANCEPROPOSED EROSION CONTROL BLANKETPROPERTY LINE1C2.189089.688989.6ATHLETIC IMPROVEMENTSBETHEL UNIVERSITY3900 Bethel DrSt Paul, MN 551123003/17/2021CITY 02/16/2021CITY RESUBMIT 03/24/2021JRPDCR0V1123087EXCERPT FROM THE SWPPP NARRATIVESECTION 1.1 SWPPP Construction Sequence1.1 SWPPP Construction Sequence1. Install perimeter silt fence where indicated on the Drawings. Silt fence shall be as specified in Section 31 25 00.2. Prior to construction, delineate turf and vegetated areas not to be disturbed with orange snow fence. No construction traffic,equipment or materials shall be permitted to utilize, access, or otherwise enter the areas designated not to be disturbed. Minimize soilcompaction and disruption of topsoil in areas outside the construction limits to comply with MN Construction Stormwater GeneralPermit.3. Locally strip topsoil and push topsoil into minimum 2 foot-high temporary berms at perimeter silt fence locations for redundanterosion protection. Where possible, leave an undisturbed vegetation strip between the temporary topsoil berm and the silt fence. Siltfence shall be located downslope from the temporary berm.a. Provide temporary seed and mulch on temporary berms as described herein.a. 4. Have silt fence, sediment logs, and other erosion control devices inspected by local authorities, as required by the localauthority.5. Construct the rock construction entrance.6. Begin mass grading of the site, recognizing the following sequence:a. In fill areas, strip and stockpile soils prior to placement of subsequent fill.i. Provide temporary seed and mulch on stockpiles as described herein.ii. Provide silt fence at the base of stockpiles, full perimeter. This silt fence is not shown on the plans but shall be included in theContractor's lump sum bid.b. In cut areas, strip and stockpile soils prior to placement of subsequent fill.i. Provide temporary seed and mulch on stockpiles as described herein.ii. Provide silt fence at the base of stockpiles, full perimeter. This silt fence is not shown on the plans but shall be included in theContractor's lump sum bid.7. Establish subgrade elevations for synthetic turf field, running track and field events and other paved areas.8. Simultaneously with mass grading work, begin installation of utilities.a. Construct proposed storm sewer system.i. Construct Sediment Control Devices at proposed storm sewer inlets (hay bales around castings and silt fence under castings willnot be acceptable).ii. Begin construction of the underground retention system.(1) Protect the underground retention system during construction.(2) Construct the temporary berm around the excavation to prevent construction site sediment from reaching theunderground retention system. The temporary berm can be a simple wind row of soil pushed into a berm from theadjacent area.(3) Do not allow sediment to reach the underground system. Maintenance of Sediment Control Devices is critical until theupslope areas are stabilized.(4) Once backfilling the underground retention system is complete, remove the temporary berm.b. Construct proposed water service.9. Construct retaining walls.10. Construct bleacher footings and foundations, including backfill.11. Begin placement of sand sub-base in track and field events and synthetic turf field areas.a. Install collector drain tile system and complete sand subbase installation.12. Install fabric and porous rock base material over turf field.13. Construct turf curb around perimeter of running track; construct trench drain between high jump and running track, between steeplechase runway and running track, and adjacent to fence near east of long-triple jump/ pole vault area.14. Complete stabilization of the outlying vegetated areas (note, establishment of permanent vegetation will be accomplished by theOwner).a. Prior to spreading topsoil, till all subgrade soils that will receive topsoil to a minimum depth of 12 inches as specified in Section31 00 00 Earthwork.b. Spread topsoil and finish grade the outlying areas.c. Prepare these areas for final seeding (by Owner).d. Provide final seed and erosion control blanket (where indicated on the drawings) or seed and mulch where erosion blanket is notindicated (by Owner). This will serve as permanent stabilization for the outlying vegetated areas.15. Continue construction of the track and field event areas and trails using the following sequence:a. Construct the first lift of pavement in the track and field event areas and trails. This will serve as permanent stabilization for theareas.b. Sod the areas surrounding the track and field event areas and trails.c. At this time, these areas will be completely stabilized with the first lift of pavement and the sod installed.16. Construct the Filtration Areas.a. The basin relies on infiltration through the soil media to properly function. Therefore, it is critical to maintain or enhance theinfiltrating properties of the soils within the area. Options to accomplish include the following:i. Limit construction traffic within the area as much as possible to avoid compacting the soils in the area.ii. Use a toothed bucket backhoe to excavate soils. Use off road trucks to haul and dump soils to other parts of the site.iii. Use a bucket and backhoe to place soils (where fill is required).iv. Use a toothed bucket for rough grading.v. Use manual labor for finish grading.vi. Do not use equipment on the surface of the area as this will compact the soils. Minimize smearing of the soils with mechanicalequipment.vii. No stockpiling of soils or other materials shall occur within the area.i. b. Rough grade the Filtration area to specified tolerances and in accordance with the procedures listed in Section 31 00 00Earthwork.i. Access the area at a single location to minimize disturbance to the surrounding areas.ii. Use of self propelled equipment shall be limited within the Filtration Area. Self propelled equipment will compact the soils andadversely affect infiltration. As much as possible, access work in the Filtration area from the edges, outside of the Filtration arealimits.iii. Use a backhoe with long reach ability for final excavation that reaches from outside the area.iv. Remove all debris by hand.v. Scarify the existing underlying soils as specified in Section 31 00 00 Earthwork.c. Provide final grading and final restoration at the Filtration Area, including:i. Access the areas at a single location to minimize disturbance to the surrounding areas.ii. Use of self propelled equipment shall be as described above. Do not use skid steer equipment within the area.iii. Final grade by hand.iv. Provide Mineral Sod within the Filtration Area limits. Sod the surrounding areas by hand.v. Establish vegetation by watering with a temporary irrigation system. Refer to Section 31 00 00 Earthwork for additionalinformation.17. Provide final lift of pavement.18. Construct site fencing.19. Complete stabilization of the outlying vegetated areas (note, establishment of permanent vegetation will be accomplished by theOwner).a. Prior to spreading topsoil, till all subgrade soils that will receive topsoil to a minimum depth of 12 inches as specified in Section31 00 00 Earthwork.b. Spread topsoil and finish grade the outlying areas.c. Prepare these areas for final seeding (by Owner).d. Provide final seed and erosion control blanket (where indicated on the drawings) or seed and mulch where erosion blanket is notindicated (by Owner). This will serve as permanent stabilization for the outlying vegetated areas.20. Install landscaping and plantings.21. Install resilient surface over running track and field events.22. Provide final stabilization and cleanup of the site.Provide maintenance to erosion control devices and BMP's to comply with the requirements of the permit.Re-install all sediment control practices that have been adjusted or removed to accommodate short-term activates, such as passage ofconstruction vehicles or equipment, immediately after the short-term activity has been completed. All sediment control practices shall bere-installed before the next precipitation event if the short-term activity is not complete.1.5 Erosion Control Device InspectionProvide maintenance to erosion control devices and BMP's to comply with the requirements of the permit.Re-install all sediment control practices that have been adjusted or removed to accommodate short-term activates, such as passage ofconstruction vehicles or equipment, immediately after the short-term activity has been completed. All sediment control practices shall bere-installed before the next precipitation event if the short-term activity is not complete.Inspect erosion control devices and provide routine maintenance as follows:1. Inspect erosion control a minimum of once per week and after each rain event measuring 0.5" or more. Provide a rain gauge at thesite and use the rain gauge to document rainfall events. Record inspection on log posted in Contractor's construction trailer or othersuitable temporary storage area.a. Records of each inspection and maintenance activity shall include:i. Date and time of inspectionsii. Name of person conducting inspectioniii. Findings of inspections, including recommendations for corrective actions(1) Findings shall include photographs, accurate description of the observations (i.e., color, odor, settled or suspendedsolids, oil sheen, or other pollutants), and a map describing the locations of the observationsiv. Corrective actions taken (including dates, times, and party completing maintenance activitiesv. Date and amount of all rainfall events greater than one quarter inch (0.25 inch) in 24 hoursvi. Documentation of changes made to the SWPPP as required by the NPDES General Stormwater Permit for Construction Activity(MN R100001)b. Inspections are not required where the ground is frozen. The required inspections and maintenance schedule must begin within 24hours after runoff occurs at the site or 24 hours prior to resuming construction, whichever comes first.c. Inspections of areas with permanent cover may be reduced to once per month, even if construction activity continues on otherportions of the site. Once all construction activity is complete, monthly inspections may be terminated after one year followingcompletion of all construction activities.2. Provide maintenance for all devices as follows:a. Silt fences, sediment logs, and erosion control devices at storm sewer inlets shall be inspected for depth of sediment, tears, to seeif fabric is securely attached to support posts or structure, and to see that posts and devices are securely in place.b. Silt fences, sediment logs and erosion control devices at storm sewer inlets, and other erosion control devices shall be cleanedwhen sediment reaches 1/3 the height of the erosion control device, within 24 hours.c. Rock construction entrances shall be inspected for clogging of river rock. River rock that has become clogged with sedimentshall be removed and replaced with fresh river rock.a. d. Repairs or replacements to all erosion control devices shall occur within 24 hours of discovery.e. Temporary diversion berms shall be inspected and any breaches promptly repaired.f. Tracked sediment from construction vehicles on to public streets and paved areas (including paved areas on the construction site)shall be removed within 24 hours of discovery.g. Removal of sediment and restabilization of Surface Waters shall be accomplished within 7 days of discovery (note: surfacewaters include curb and gutter, pavements, storm sewer, swales, or other similar storm water conveyance devices).h. Inlet protection may be removed if a local unit of government directs the permittee to do so because of a specific safety concern.3. Street sweeping (with a pickup broom only) will be provided as needed or at the direction of the Owner / Engineer.1.6 Temporary Soil StockpilesTemporary soil stockpiles shall not be placed in surface waters of the state, including surface conveyances such as curb and gutter, swales,or ditches.Temporary soil stockpiles shall be seeded with temporary seed mix and hydromulch when stockpiles are left inactive for seven (7) days.Note, this does not apply to aggregate stockpiles or other stockpiles without significant silt, clay or organic components (clean aggregatestockpiles, clean rock, clean sand and similar clean aggregates).Provide silt fence at the base of all stockpiles, including clean aggregate and similar stockpiles, full perimeter.Denuded AreasStabilize denuded areas, initiated immediately, within 7 days of last construction activity (temporary or permanent) in that area except fortemporary soil stockpiles.Temporary soil stockpiles shall be treated with appropriate erosion control measure, including silt fence and temporary seeding whenstockpiles are left inactive for periods longer than 7 days.1.7 Steep Slope DisturbancesSteep slopes, defined as slopes steeper than three feet horizontal to one foot vertical, are not proposed for this project. Therefore, nospecial provisions are required.1.8 Dewatering PracticesProvide dewatering of excavations as identified in Section 31 00 00.1.9 Substantial Completion / Turf Establishment1. Provide maintenance of all seeded areas until fully established (by Owner).2. Provide cleaning of storm sewer system at the completion of the project.a. Cleaning shall include removal of accumulated sediment from all surface waters as defined by the permit (for example, curb andgutter, pavements, swales, and storm sewer piping and structures).3. Remove silt fence and erosion control devices at storm sewer inlets following full establishment of site vegetation. Dispose materialsproperly off-site.4. Apply for Notice of Termination (NOT) with MPCA. NOT must be submitted within 30 days after:a. Site has undergone Final Stabilization (at least 80% vegetative cover), andb. Removal of all temporary erosion control measures (silt fence, etc.), andc. Final cleanout and maintenance of all permanent storm water facilities, anda. d. Completion of all maintenance activities and site cleanup.2.1 Temporary Stabilization1. Stockpiles and disturbed portions of the site where construction activity temporarily ceases for the time frames noted above shall bestabilized with a temporary seed and mulch according to the following:a. All areas of bare soil exposed to possible erosion shall be shaped to drain with minimum potential for erosion. The disturbedareas shall then be seeded with perennial ryegrass and annual wheat at a rate of 10 pounds per acre (0.25 lbs./1,000 sq. ft.) and 20pounds per acre (0.50 lbs./1,000 sq. ft.) respectively, then and covered with hydromulch (Mn/DOT 3884, Type 5 consisting ofwood cellulose fiber pulp) at a rate of 1,500 pounds per acre (note, where erosion control blanket is proposed, hydromulch is notrequired).b. Stabilize areas to be paved by placing Class V aggregate base course.2. Permanent Stabilization:a. Permanent stabilization shall occur in accordance with Specification Sections 32 12 16, 32 16 13, 32 16 23, 32 92 19, 32 92 23,and 32 93 00 and as shown on the Construction Drawings.
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