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HomeMy WebLinkAboutLong Term PPP revisedLONG TERM POLLUTION PREVENTION AND OPERATION AND MAINTENANCE PLAN. 228 Route 28 Yarmouth MA Proposed A Plus Market LONG-TERM POLLUTION PREVENTION AND OPERATION AND MAINTENANCE PLAN Revised 10/22/2024 Introduction As required by Standards 4 and 9 of the Stormwater Management Handbook and Section 2.07 of the Town of Yarmouth Stormwater Management Regulations, this Long-Term Pollution Prevention and Operation and Maintenance Plan has been developed for source control and pollution prevention at the site after construction. Maintenance Responsibility The responsibility of the Long-Term Pollution Prevention and Operation and Maintenance Plan will be that of the Owner or their heirs or assigns. Estimated budget for Stormwater Maintenance Activities: The estimated annual budget for the routine maintenance of stormwater facilities is as follows: Catch basin cleaning: $ 300.00 Stormceptor inspection/cleaning: $ 300.00 Pavement sweeping: $ 300.00 Maintenance of the Exfiltrating Rain Garden will be incorporated into the regular landscape maintenance performed regularly and the cost is included in that budget. Routine visual inspection tasks are understood to be performed by facility staff and are not included in the above estimates. Good Housekeeping Practices Trash/Litter Management The site is to be kept clean of trash and debris at all times. All generated trash and rubbish is to be deposited in covered dumpsters. Dumpsters shall be screened from view and emptied on a regular basis. Street Sweeping Street Sweeping will be provided on the property’s paved surfaces at least twice annually to mitigate potential dust. Regenerative Air sweepers are not recommended for use at this site as these blow air onto the paved surface, causing fines to rise during sweeping activities. Car washing Car and vehicle washing are not proposed as uses on the property, and residents will be discouraged from washing cars in the parking area. A car wash business is available to residents 2 miles from the property. Stormwater BMPs All stormwater BMPs are to be inspected and maintained as follows: Catch Basin. Inspect and/or clean catch basins quarterly as part of the regular inspection schedule. Remove accumulated trash and debris from the grates upon discovery. Inspect the integrity of the frames and grates and repair or replace as needed. Record sediment depth and/or the presence of floating oils during each quarterly inspection. Remove sediments two times per year at a minimum or whenever the depth of deposits in the sumps is greater than 12 inches (25% of sump) by clamshell buckets or preferably vacuum truck, as the clamshell buckets can damage the interior tee/hood. Increase inspection frequency if depth of sediment deposits regularly exceeds 12 inches. Ensure that only accumulated sediment is removed and not the underlying soil that supports the structure, if it is a drywell. Dispose of catch basin sediments in accordance with all applicable regulations and policies. In the absence of evidence of contamination, catch basin sediments can be accepted by landfills as solid waste. Some landfill operators may require testing. Contaminated water or sediments removed from catch basins should be disposed of in accordance with all applicable local, state and federal laws and regulations including M.G.L.c. 21C and 310 CMR 30.00. Drain lines. After construction, the drain line shall be inspected visually from either end after every major storm for the first few months to ensure proper functions. Presence of accumulated sand and silt would indicate more frequent maintenance of the pre-treatment devices is required. Thereafter, the drainlines shall be inspected biannually. Stormceptor. Maintenance of the Stormceptor system is performed using vacuum trucks. No entry into the unit is required for maintenance (in most cases). The need for maintenance can be determined easily by inspecting the unit from the surface. The depth of oil in the unit can be determined by inserting a dipstick in the oil inspection/cleanout port. Similarly, the depth of sediment can be measured from the surface without entry into the Stormceptor via a dipstick tube equipped with a ball valve. This tube would be inserted through the riser pipe. Maintenance should be performed once the sediment depth exceeds 8 inches for the 450i model. Although annual servicing is recommended, the frequency of maintenance may need to be increased or reduced based on local conditions (i.e. if the unit is filling up with sediment more quickly than projected, maintenance may be required semi-annually; conversely once the site has stabilized maintenance may only be required every two or three years). Oil is removed through the oil inspection/cleanout port and sediment is removed through the riser pipe. Alternatively, oil could be removed from the 24 inches (600 mm) opening if water is removed from the lower chamber to lower the oil level below the drop pipes. The following procedures should be taken when cleaning out Stormceptor: 1. Check for oil through the oil cleanout port 2. Remove any oil separately using a small portable pump 3. Decant the water from the unit to the sanitary sewer, if permitted by the local regulating authority, or into a separate containment tank 4. Remove the sludge from the bottom of the unit using the vacuum truck 5. Re-fill Stormceptor with water where required by the local jurisdiction Rain Garden. Premature failure of bio retention areas, to include rain gardens, is a significant issue caused by lack of regular maintenance. Ensuring long-term maintenance involves sustained public education and deed restrictions or covenants for privately owned cells. Bio retention areas require careful attention while plants are being established and seasonal landscaping maintenance thereafter. Inspect sediment traps and inlets to the bio-retention cells regularly for sediment build-up, structural damage, and standing water. Remove any litter and/or debris collected in rain garden or its sediment trap upon discovery. Verify the trap is level and distributing water equally. Inspect side slopes and riprap. Repair as necessary. Re-mulch void areas as needed. Inspect Vegetation. Remove any invasive species upon discovery. Annually in the spring investigate the plant mortality as periodic die off is expected. Replace dead vegetation in kind. Treat diseased vegetation as needed. Remove and replace dead vegetation twice per year (spring and fall). The shredded wood mulch will require replacement once every two years (preferably in the early spring) or when the material gets “blinded”. Replacement material shall NOT be ornamental dyed product commonly used in landscapes but rather simple shredded wood, The bio-retention soil should be replaced every 10 years. Never store plowed snow in bio retention areas. Snow Disposal and Plowing Plowed snow shall be stored on unused areas of pavement. Snowmelt from snow storage areas shall be routed through the catchbasin, Stormceptor, or vegetated filter strip for the removal of TSS and other non-water components prior to discharge. Dumping of snow into any water body, including rivers, ponds, or wetlands (including the on-site stormwater infiltration basin and rain garden) is prohibited. Snow disposed of in open water can cause water quality impacts and flooding. Training The long-term pollution prevention plan is to be implemented by the property owner of the site. Trained and, if required, licensed professionals are to be hired by the owner as applicable to implement the long-term pollution prevention plan. Emergency Contacts The owner will be required to maintain an updated list of Emergency Contacts for the site. This list will be provided to the Yarmouth Conservation Commission. 1. Refer to the Massachusetts Stormwater Standards (current version) for recommendations regarding frequency for inspections and maintenance of specific BMP.