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HomeMy WebLinkAboutOperation & Maintenance ManualOperation and Maintenance Manual for Meridian Main 1, Lot 1 Building 1 Carmel, Indiana Prepared for: Meridian 131, LLC 6100 West 96th Street Indianapolis, IN 46278 February 17, 2012 Crape Architects Engineers Soiutions by Design Since 1937 3939 Priority Way South Drive, Suite 400 Indianapolis, Indiana 46240 Telephone 317 844 6777 Facsimile 317 706 6464 www.cripe.biz PIC: 060384 -20310 Operation and Maintenance Manual Stormwater Treatment System for Lot 1, Building 1 Meridian and Main I Carmel, Indiana TABLE OF CONTENTS 1.0 Introduction 2 1.1 Project Description 2 1.2 Purpose and Performance 2 2.0 Water Quality Maintenance 3 -5 2.1 Maintenance and Inspections 3 -5 2.2 Documentation 5 3.0 Owner's Acceptance 5 Owner Acknowledgement Agreement Appendix A Operation and Maintenance 1 1.0 Introduction The City of Carmel has adopted a policy in compliance with the National Pollutant Discharge Elimination System (NPDES) stormwater permit to control and improve the water quality of stormwater runoff. The water quality management program is based on the performance of approved structural Best Management Practices (BMP) to remove 80% of total suspended solids (TSS) from the first 1 -inch of storm water runoff. Design requirements and parameters may be found in the City of Carmel Stormwater Technical Standards Manual. 1.1 Project Description The proposed Meridian and Main, Lot 1, Building 1 construction shall include an approximately 13,000 sf building, access drive, parking lot, sidewalks, landscape, utilities and other pertinent amenities for the site. This lot is part of the overall masterplan that includes one stage of water quality treatment via the infiltration basins for water quality treatment. For Lot 1, Building 1, an additional BMP is added for the treatment train. The first BMP in the treatment train shall be the VortSentry HS 36 Unit which shall remove the largest and heaviest of the suspended solids as well as floatables in the stormwater runoff. The second treatment, the Infiltration Basin Pond 1 from the Master Plan, shall filter the residual TSS as well as hydrocarbons and pollutants remaining in the stormwater. This treatment train shall exceed the stormwater treatment capacity as mandated by the City of Carmel. 1.2 Purpose and Performance In order to achieve the 80% target removal rate of TSS from the stormwater runoff associated with the proposed improvements, an Infiltration Basin and a mechanical BMP (VortSentry Unit) were selected based on the physical site characteristics, cost, and the water quality treatment volume to be treated per City of Carmel requirements. The benefits of these types of BMP's are very high pollutant removal rates. Provision of one element of the treatment train is part of the overall Masterplan. Provision for the additional BMP is to be provided with the future development of each lot. The BMP's are located prior to the discharge of the storm system from the site and have been sized according to the City of Carmel Stormwater Technical Standards Manual. Lot 1, Building 1 of Meridian and Main I shall be treated with two forms of BMPs. The first mechanical BMP has been sized using the Water Quality Curve Number as calculated using the City of Carmel Stormwater Technical Standards Manual for the Lot 1, Building 1 site. (See Calculations and Exhibits in the Drainage Report) and the second BMP for the proposed project is the Infiltration Basin. 2 Inspection Item: Sediment Sediment is to be removed when inspection reveals a top of sediment depth within 6 in. of the dry weather water surface elevation in the structure. Sediment depths can be easily determined by measuring the distance from the top of the manhole to the dry water surface elevation and then measuring the distance from the top of the manhole to the top of the sediment pile. This can be done with a steel tape or stadia rod. The system should be pumped clean using a high velocity vacuum truck. Free floating oil and floatable debris use a high velocity vacuum truck to clean the pollutants. After recording the measurements on the Inspection Data Sheet (attached in Appendix B), the vacuum hose is lowered through the access opening and the floating debris. The oil may be best removed by using an absorbent pad. Usually, confined space entry can be avoided by inspecting from the manhole entrance and cleaning the system by using a vacuum hose. 2.0 Water Quality Maintenance As part of the Water Quality program, the City of Carmel is also requiring a maintenance and inspection program by the Owner for each type of BMP. 2.1 Maintenance and Inspections Routine inspections, maintenance, and the costs necessary for the maintenance and repair of the BMPs are the responsibility of the owner. The following are the recommended inspection items and timeframes for the VortSentry HS 36 Unit and the Infiltration Basins. Inspection Frequency: The manufacturer recommends quarterly inspections; however, City of Carmel Engineering Department requires annual inspection reports to be submitted to the city, in the same month as the initial inspection. Maintenance and Inspections (Mechanical BMP- VortSentry Unit) Maintenance and Inspections (Infiltration Basin) The owner will be responsible for hiring a qualified professional consultant for the first 3 to 5 years after installation to handle post installation site monitoring and 3 Inspection Item: Vegetation remove undesired vegetation along pond banks including but not limited to seedling trees and cattails, using care to avoid specific native plantings. Embankment Erosion fill and repair any rills or eroded areas from concentrated sheet flow runoff. Repair any eroded soils around the outlet structure. Reseed all disturbed areas and areas lacking grass. Levee /Dam /Berm check for animal burrows or nests. If present, obtain services of pest control or other company to remove animals. Check for soil cracking, bulging, or dam slippage. Inspect embankment for leaks, seeps, or slope protection failure. If burrows or areas of soil failure exist, obtain the services of a Licensed Professional Civil or Geotechnical Engineer for soil repair recommendations. Outlet Structure inspect outlet structure and emergency spillway for blockage and clean as necessary. Inspect and clean interior of outlet structure of any debris or sediment deposits. Inspection Item: Vegetation remove undesired vegetation along pond banks, including but not limited to seedling trees, cattails, etc., using care to avoid native plantings associated with Wet Pond BMP. Embankment Erosion fill and repair any rills or eroded areas from concentrated sheet flow runoff. Repair any eroded soils around the outlet structure. Reseed all disturbed areas and areas of insufficient vegetative cover. management. This will ensure that the infiltration basin vegetation becomes fully established. See maintenance guidelines and inspection checklist for Infiltration Basin in Appendix A. Use beginning date from table in section 2.1 for start of maintenance and inspection schedule. Inspection Frequency: Annually and After Major Rainfall Events (4 inches or more of rainfall in any 24 hour period) Inspection Frequency: Monthly 4 Mowing Requirements mow all grassed areas within the drainage easement around the pond monthly or when grass height exceeds 6 inches, using care to avoid native plantings associated with a Pond BMP. 2.2 Documentation The owner is required to maintain completed inspection reports /records and update the operations and maintenance plan for the BMP. The inspection reports shall be submitted to the City of Carmel Engineering Department annually and made available to the City upon request. 3.0 Owner's Acceptance The City and /or its representatives have the right to enter the property to inspect BMPs. The BMP Owner shall be financially responsible for any maintenance or repairs required by the City or its representatives during the City's inspections. This Operation and Maintenance Manual is submitted to the City of Carmel with the intent to insure the longevity and adequate functioning of the VortSentry HS 36 Unit and Infiltration Basin BMP owned by the Browning Real Estate Partners located at 6100 W. 96 Street, Indianapolis, IN 46278. By submitting this Operation and Maintenance Manual to the City of Carmel with plans to construct a Vortsentry HS 36 and Infiltration Basin, the BMP owner noted above agrees to follow and abide by the inspection schedule and maintenance activities listed in this manual. The BMP owner noted above is responsible for any additional maintenance and /or repair activities to maintain the function and longevity of the BMP(s). Owner Information: Jamie W. Browning Browning Real Estate Partners 6100 W. 96 Street Indianapolis, IN 46278 317- 344 -7328 JBrowning @browninginv.com 5 Owner Acknowledgement Agreement "Agreement For good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned owner "Owner hereby submits this Operation and Maintenance Manual "Manual to the City of Carmel, Indiana "City as a written acknowledgement of Owner's warranty and agreement to institute, maintain, and follow the water quality Best Management Practices ("BMPs") listed below, and to follow and abide by the inspection schedule and maintenance activities listed in this Manual. The Owner also hereby agrees to provide, at Owner's cost, all additional maintenance, repair, and /or replacement services reasonably necessary to maintain the function and longevity of the BMPs from and including the date this Agreement is executed by Owner to and including the date on which a new Agreement is filed with the City by another party who assumes all of the obligations and responsibilities of Owner as set forth herein. BMPs: Owner Signature Date Printed Name Company SS: COUNTY OF HAMILTON STATE OF INDIANA BEFORE ME, the undersigned, a Notary Public in and for said County and State, personally appeared Owner subscribed and sworn before this day of County of Residence Signature Commission Expiration Date Printed Name Vortsentry HS 36 Unit Infiltration Basin APPENDIX A VortSentry HS Maintenance The VortSentry HS system should be inspected at regular intervals and maintained when necessary to ensure optimum performance. The rate at which the system collects pollutants will depend more heavily on site activities than the size of the unit, i.e., unstable soils or heavy winter sanding will cause the treatment chamber to fill more quickly, but regular sweeping will slow accumulation. Inspection Inspection is the key to effective maintenance and is easily performed. Pollutant deposition and transport may vary from year to year and regular inspections will help ensure that the system is cleaned out at the appropriate time. At a minimum, inspections should be performed twice per year (i.e. spring and fall) however more frequent inspections may be necessary in equipment washdown areas and in climates where winter sanding operations may lead to rapid accumulations of a large volume of sediment. It is useful and often required as part of a permit to keep a record of each inspection. A simple inspection and maintenance log form for doing so is available for download at www.contechstormwater.com. The VortSentry HS should be cleaned when the sediment has accumulated to a depth of two feet in the treatment chamber. This determination can be made by taking two measurements with a stadia rod or similar measuring device; one measurement from the manhole opening to the top of the sediment pile and the other from the manhole opening to the water surface. If the difference between these measurements is less than the distance given in Table 1, the VortSentry HS should be maintained to ensure effective treatment. VortSentry HS Model Diameter" Distance Between Water Surface and Top of Storage Sump Sediment, Storage Oil Spill Storage HS36 HS48 HS60 HS72 HS84 in. m 36 0.9 48 1 2 60 1.5 72 f 1 8 84 2.1 ft. 3.6 6.0 m 1.1 1.8 Cleaning Cleaning of the VortSentry HS should be done during dry weather conditions when no flow is entering the system. Cleanout of the VortSentry HS with a vacuum truck is generally the most effective and convenient method of excavating pollutants from the system. Simply remove the manhole cover and insert the vacuum hose into the sump. All pollutants can be removed from this one access point from the surface with no requirements for Confined Space Entry. In installations where the risk of petroleum spills is small, liquid contaminants may not accumulate as quickly as sediment. However, an oil or gasoline spill should be cleaned out immediately. Motor oil and other hydrocarbons that accumulate on a more routine basis should be removed when an appreciable layer has been captured. To remove these pollutants, it may be preferable to use adsorbent pads, which solidify the oils. These are usually much easier to remove from the unit individually, and less expensive to dispose than the oil /water emulsion that may be created by vacuuming the oily layer. Floating trash can be netted out if you wish to separate it from the other pollutants. Manhole covers should be securely seated following cleaning activities to prevent leakage of runoff into the system from above and also to ensure proper safety precautions. If anyone physically enters the unit, Confined Space Entry procedures need to be followed. Disposal of all material removed from the VortSentry HS should be done is accordance with local regulations. In many locations, disposal of evacuated sediments may be handled in the same manner as disposal of sediments removed from catch basins or deep sump manholes. Check your local regulations for specific requirements on disposal. yd m gal. liter 0.5 0.4 83 314 '1.5 258 978 8.4 2.6 2.9 2.2 649 2458 Table 1: VortSentry HS Maintenance Indicators and Sediment Storage Capacities. VortSentry HS Inspection Maintenance Log VortSentry HS Model: Location: Date Water depth to shipment' Floatable Layer Thickness Describe Maintenance Performed Maintenance Personnel Comments 1. The water depth to sediment is determined by taking two measurements with a stadia rod: one measurement from the manhole opening to the top of the sediment pile and the other from the manhole opening to the water surface. If the difference between these measurements is less than the distance given in Table 1, the system should be cleaned out. Note: To avoid underestimating the volume of sediment in the chamber, the measuring device must be carefully lowered to the top of the sediment pile. 2. For optimum performance, the system should be cleaned out when the floating hydrocarbon layer accumulates to an appreciable thickness. In the event of an oil spill, the system should be cleaned immediately. Stormwater Ordinance Technical Standards Post-Construction BMP Inspection Checklist Infiltration Basin Infiltration Basin Operation, Maintenance, and Management Inspection Checklist Project: Location: Date: Inspector: Signature: Inf. Basin O &M I oft Time: Title: Maintenance Item 1. Debris Cleanout Basin bottom clear of debris Inlet clear of debris Outlet clear of debris Emergency spillway clear of debris 2. Sediment Traps or Forebays Obviously trapping sediment Greater than 50% of storage volume remaining Mowing done when needed No evidence of erosion Basin dries out between storms Satisfactory/ Unsatisfactory Comments ,s 3. Vegetation 4. Drying Out July 2004 Maintenance' Item Satisfactory/ 'Unsatisfactory Comments 5. Sediment Cleanout of Basin No evidence of sedimentation Sediment accumulation does not yet require cleanout 6. Inlets Good condition No evidence of erosion 7. Outlets /Overflow Spillway Good condition, no need for repair No evidence of erosion 8. Structural Repairs Embankment in good repair Side slopes are stable No evidence of erosion 9. Fences /Access Repairs Fences in good condition No damage which would allow undesirable entry Lock and gate function adequate Access point in good condition Post Construction BMP Inspection Checklist Infiltration Basin Actions to be Taken: Stormwater Ordinance Technical Standards Inf. Basin O &M 2 of 2 July 2004