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Home My WebLink AboutCDP 05-19; TOYOTA CARLSBAD; WATER QUALITY TECHNICAL REPORT DWG 441-6A; 2005-04-08WATER QUALITY TECHNICAL REPORT Toyota Carlsbad Service Facility 6030 Avenida Encinas City of Carlsbad CDP 05-19/DWG. NO. 441-6A Prepared for: Stellar Properties, LLC 5424 Paseo Del Norte Carlsbad, CA 92008 Prepared By: BhA, Inc. Land planning, civil engineering, surveying 5115 Avenida Encinas, Suite L Carlsbad, CA 920084387 (760) 9318700 PL*- _e:CK NO. ^ April 8,2005 Revised September 15,2006 W.O. 591-0804-605 TABLE OF CONTENTS 50//^ S Z dZS INTRODUCTION Project Description Pollutants and Condition of Concern ESTABLISH PERMANENT STORM WATER BEST MANAGEMENT PRACTICES Site Design BMPs Source Control BMPs BMPs Applicable to Individual Priority Project Categories Treatment Control BMPs OPERATION AND MAINTENANCE PROGRAM Maintenance Schedule and Cost for BMPs REFERENCE ATTACHMENTS 1. Vicinity Map 2. Site Map 3. Storm Water Requirements applicability Checklist 1 INTRODUCTION A Water Quality Technical Report (WQTR) is required under the City of Carlsbad's storm water management requirements. According to the Storm Water Requirements Applicability Checklist, this project is subject to Priority Project Permanent Storm Water BMP Requirements and Standard Permanent Storm Water BMP Requirements. The purpose of this WQTR is to describe the permanent storm water Best Management Practices (BMPs) that will be incorporated in the project to mitigate the impacts of urban runoff due to the development. This WQTR is intended to ensure the effectiveness of the BMPs through maintenance that is based on long-term planning. The WQTR is subject to revisions as needed by the engineer. 1.1 Project Description Service FaciUty for Toyota Carlsbad, 6030 Avenida Encinas, is located on the east side of Avenida Encinas, just south of the intersection of Avenida Encinas and Palomar Airport Road. The 9.76 acres site is zoned for industrial use. Currently, the property is being used as a body and painting facility and office building for Toyota Carlsbad. This project proposes the demolition of the office building and replacing it with a automobile service facility/parking structure and reconfiguring portion of the onsite parking spaces. 1.2 Pollutants and Condition of Concern A. Identify Pollutants from the Project Area Using Table 2, Anticipated and Potential Pollutants Generated by Land Use Type from City of Carlsbad Standard Urban Storm Water Mitigation Plan, we have identified the anticipated and potential pollutants generated by this project. The anticipated pollutants are heavy metals, organic compounds (petroleum hydrocarbons and solvents), trash & debris. Oil and grease. Sediments, nutrients, oxygen demanding substances, and pesticides are potential pollutants of concern because this project proposes landscaping. The anticipated pollutants from the automotive repair category will be treated on-site and will not be discharged into the storm drain system. The runoff from the proposed development are treated by the proposed filtration systems at the end of the proposed storm drain system so that the runoff is filtered before exiting the site. Table 2. Anticipated and Potential Pollutants Generated by Land Use Type. Genera/ Pollutant Categories Project Categories Sediments Nutrients Heavy Metals Organic Compounds Trash & Debris Oxygen Demanding Substances Oil& Grease Bacleria & Viruses Pesticides Detached Residential Development X Attached Residential Deveiopment pd) P(2) piD Gommercial Development >100,000 ft2 p(i) p(i) p(2) P(51 P(31 P(5) Automotive Repair Restaurants Hillside Development >5,000ft2 X Parking Lots p(i) pd) pd) p(i) Streets, Highw/ays & Freeways P(i)x Xd) P15) X = anticipated P = potential (1) A potential pollutant if landscaping exists on-site. (2) A potential pollutant if the project includes uncovered parking areas. (3) A potential pollutant if land use involves food or animal waste products. (4) Including petroleum hydrocarbons. (5) Including solvents. B. Identify Pollutants of Concern in Receiving Waters This project discharges its runoff to the Encinas Hydrologic Sub-area (904.40), part of Carlsbad Hydrologic Unit (904.00). According to the California 2002 303d Ust published by the San Diego Regional Water Quality Control Board, there are no impaired water bodies that are associated with this project. Service Facility for Toyota Carlsbad's location and watersheds have been compared to the current published 303d Ust of impaired water bodies. The nearest impaired water body is Pacific Ocean Shoreline at San Marcos HA (904.51). Pacific Ocean Shoreline at San Marcos HA is impaired with Bacteria. C. Identify Conditions of Concern A Hydrology and Hydraulic Report has been prepared for Toyota Carlsbad Service Facility, dated April 5, 2005. As part of the drainage study, a field reconnaissance was conducted for this project. No detrimental effect was observed onsite. The existing outlet structure remains in good condition and no sign of erosion was observed. The potential of downstream erosion is minimal because the runoff from the development is proposed to be released into an existing storm drain in Avenida Encinas and the existing outlet structure remains in good condition. 2 Establish Permanent Storm Water Best Management Practices To address water quality for the project, permanent BMPs wiU be incorporated into the project design. Anticipated and potential pollutants of concern as noted in Table 2 wiU be addressed through four types of BMPs. These types of BMPs are Site Design, Source Control, BMPs for Individual Priority Project Categories and Treatment Control. A. Site Design BMPs Control post-development peak storm runoff discharge rates and velocities to maintain or reduce pre-development downstream erosion by applying the following concepts: Increasing building density (multi-story building). • Driveways and parking lot aisles have been designed to meet the minimum width. This project will not increase post-development runoff. B. Source Control BMPs Source control BMPs wiU consist of measures to prevent poUuted runoff. • Trash storage areas shall be paved with an impervious surface, designed not to aUow run-on from adjoining areas, waUed to prevent off-site transport of trash and contain attached lids on aU trash containers that exclude rain. • Employ rain shutoff devices to prevent irrigation during and after precipitation; and use flow reducers or shutoff valves triggered by a pressure drop to control water loss in the event of broken sprinkler heads or Unes. • Design irrigation systems to each landscape area's specific water requirements. • Provide concrete stamping, or equivalent, of aU storm water conveyance system inlets and catch basins within the project area with prohibitive language (e.g., "No Dumping -1 Live Downstream".), satisfactory to the City Engineer. C. BMPs Applicable to Individual Priority Project Categories Dock Area: • Loading/unloading dock areas shall include the following: (1) cover loading dock areas, or design drainage to preclude urban run-on and runoff; or (2) Direct connections to storm drains from depressed loading docks (truck wells) are prohibited. Maintenance Bays: • Repair/maintenance bays are indoors. • The discharges from the maintenance bays' will be pre-filtered and released into the sanitation system. Vehicle & Equipment Wash Areas: • Areas for washing/steam cleaning of vehicles and areas for outdoor equipment/accessory washing and steam cleaning is self-contained to preclude run- on and run-off, covered with a roof or overhang, and equipped with a clarifier or other pretreatment facility; (2) properly connected to a sanitation sewer if appropriate. Where areas are connected to a sanitary sewer, an Industrial Waste Permit may be required from the Encina Water Pollution Control FaciUty. Surface Parking Areas: Incorporate landscaping into drainage design when possible. Non-Retail Fueling Areas • Not Applicable 2.3 Treatment Control BMPs The following treatment control BMPs wUl be implemented to address water quality. • Media Filtration Device (VortFilter by Vortechnics) VortFilter Cartridge is filled with Periite, Granular Activated Carbon and Zrolite. VortFilter is capable of removing particles as small as 7 Microns at a flow rates ranging from 7.5 gpm to 20 gpm. Placement of the BMPs are noted on the WQTR Exhibit. 3 OPERATION AND MAINTENANCE PROGRAM The operation and maintenance requirement for each type of BMP is as follows: 3.1 Maintenance Schedule and Cost for BMPs Media Filter (VortFilter by Vortechnics) Routine Action Maintenance Indicator Field Measurement Measurement/ Inspection Frequency Maintenance Activity Site-Specific Requirement Cost per filter Inspect for sediment accumulation in Pre-treatment sedimentation chamber Sediment occupies 10% of the filter chamber volume Measure with appropriate device Annually in May $201.36 Remove sediment prior to wet season. Characterize sediment and properly dispose $970.32 Inspect for minor maintenance Per manufacture's guidelines None Annually Qean per manufacturer's guidelines. Prior to wet season. $201.36 Media Filter (VortFilter by Vortechnics) .S c 0 t> 01 < a o 3 C E g & S 8.1 2 £ £ 4) .C^ II o c a. i- a g" 55 Di Q ^ Si Manufacturer's recommended major maintenance Per manufacture's guidelines Per manufacture's guidelines Annually Consult with manufacturer regarding need for replacement of canisters. If manufacturer confirms need, replace canisters. Prior to wet season. When canisters are changed send canisters to manufacturer to determine remaining life of the media $5375.88 (by contract and oversite) Inspection for trash and debris at inlet and outlet structures and with in vaults Trash/debris present Visual observation During routine trashing. Remove and dispose of trash and debris when on site conducting inspections. $0 Inspection for standing water Water accumulation in any structure or other location within the filter Standing water in any structure or other location within the filter Annually, at end of wet Gravity drain where possible. $0 If standing water can not be removed of remains through wet season notify VCD. $0 (Does not include Vector Control Agency costs) General Maintenance Inspection Inlet structures, outlet structures, vault, piping, or other features damaged and for graffiti or vandalism Visual observation Semi-Annually, late wet season. Consult engineer if immediate solution is not evident. Take corrective action prior to wet season. Consult engineer if immediate solution is not evident. Total $402.72 $7151.64 3.1 Numeric Sizing Calculation for BMPs For Flow Based BMPs: Q=CIA C=0.87 1=0.2 A=2.6 ac Q=(0.87)x(0.2)x(2.6) Q=0.45 cfs Use one cartridge Responsible Party Information: Stellar Properties 5424 Paseo Del Norte Carlsbad, CA 92008 Bob Wolf 760-497-7286 4 REFERENCE Water Quality Control Plan for the San Diego Basin (9) CaUfornia Regional Water Quality Control Board, San Diego Region, September 8,1994 County of San Diego, Standard Urban Storm Water Mitigation Plan for Land Development and Public Improvement Projects, February 2003 California Stormwater Best Management Practice Handbook, Municipal, March 1993 2002 CWA Section 303(d) List of Water Quality Limited Segment, February 2003 ATTACHMENT "A" VICINITY MAP ATTACHMENT "B" SITEMAP ATTACHMENT "C" STORM WATER REQUIREMENTS APPLICABILITY CHECKLIST PAGE TO BE REMOVED IN FINAL REPORT vo)$ 21B&C1W1*U&6 T&/ Q -(6 %&E!9$ &/ Q &9#!((&E$ &3$ 91U*$ 3&"6 &)1"1U!"$ &G1* 20*6 TT&J26 30B$ 3&T26 ) & I Sc2 ! 1*T 1 ( (" $ 9"6 2)&$ @$ *"L *91"5Sc6 T&<L.Scl* fd4a' 4d<L>, fdG<L>,IG<L.IG?L+I f?d<L?> f.dG<L>,IG<L.IG.I f .d<L.^- f&l"&V6 3$ &:><&d<L?>k<L.-i-d<L+ = <L+=&BT9&T6 2&"#$ &%#6 ($ &91"$ L ad<L, '?d?L+ ' .d. MX&F&F&[9$ B!J!B1"5&J$ &C"6 2)'-l{"$ 2&G4/C~-?&%N&?5cB!2"213U$ 2&B!2"213U$ &19&<L?-i-&BT9L I&E MX&F&F&[9$ &[ ("2!F[2E1*&T1("$ 2Sc%NC) !2"ScCJ6 *U$ &GS B1J!B1"5&J$ 2&T1("$ 2&19&<L-i-; ScBT9L&: 6<DA=0=R<%@LD%6<DA@NO:I%#BC WATER QUALITY TECHNICAL REPORT for Toyota Carlsbad Service Facility 6030 Avenida Encinas City of Carlsbad CDP 05-19/DWG. NO, 441-6A Prepared for: SteUar Properties, LLC 5424 Paseo Del Norte Carlsbad, CA 92008 Prepared By: BhA, Inc. Land planning, civil engineering, sun/eying 5115 Avenida Encinas, Suite L Carlsbad, CA 920084387 (760) 9318700 April 8,2005 Revised September 15, 2006 W.O. 591-0804-605 TABLE OF CONTENTS INTRODUCTION Project Description Pollutants and Condition of Concern ESTABLISH PERMANENT STORM WATER BEST MANAGEMENT PRACTICES Site Design BMPs Source Control BMPs BMPs Applicable to Individual Priority Project Categories Treatment Control BMPs OPERATION AND MAINTENANCE PROGRAM Maintenance Schedule and Cost for BMPs REFERENCE ATTACHMENTS 1. Vicinity Map 2. Site Map 3. Storm Water Requirements applicability CheckUst 1 INTRODUCTION A Water Quality Technical Report (WQTR) is required under the City of Carlsbad's storm water management requirements. According to the Storm Water Requirements AppUcabUity Checklist, this project is subject to Priority Project Permanent Storm Water BMP Requirements and Standard Permanent Storm Water BMP Requirements. The purpose of this WQTR is to describe the permanent storm water Best Management Practices (BMPs) that will be incorporated in the project to mitigate the impacts of urban runoff due to the development. This WQTR is intended to ensure the effectiveness of the BMPs through maintenance that is based on long-term planning. The WQTR is subject to revisions as needed by the engineer. 1.1 Project Description Service FaciUty for Toyota Carisbad, 6030 Avenida Encinas, is located on the east side of Avenida Encinas, just south of the intersection of Avenida Encinas and Palomar Airport Road. The 9.76 acres site is zoned for industrial use. Currently, the property is being used as a body and painting facUity and office building for Toyota Carlsbad. This project proposes the demolition of the office building and replacing it with a automobile service facUity/parking structure and reconfiguring portion of the onsite parking spaces. 1.2 Pollutants and Condition of Concern A. Identify Pollutants from the Project Area Using Table 2, Anticipated and Potential Pollutants Generated by Land Use Type from the City of Carlsbad Standard Urban Storm Water Mitigation Plan, we have identified the anticipated and potential pollutants generated by this project. The anticipated pollutants are heavy metals, organic compounds (petroleum hydrocarbons and solvents), trash & debris. Oil and grease. Sediments, nutrients, oxygen demanding substances, and pesticides are potential pollutants of concern because this project proposes landscaping. The anticipated pollutants from the automotive repair category will be treated on-site and wiU not be discharged into the storm drain system. The runoff from the proposed development are treated by the proposed fihration systems at the end of the proposed storm drain system so that the runoff is filtered before exiting the site. B. Identify Pollutants of Concern in Receiving Waters This project discharges its runoff to the Encinas Hydrologic Sub-area (904.40), part of Carisbad Hydrologic Unit (904.00). According to the California 2002 303d list published by the San Diego Regional Water Quality Control Board, there are no impaired water bodies that are associated with this project. Service FacUity for Toyota Carlsbad's location and watersheds have been compared to the current published 303d list of impaired water bodies. The nearest impaired water body is Pacific Ocean Shoreline at San Marcos HA (904.51). Pacific Ocean Shoreline at San Marcos HA is impaired with Bacteria. C. Identify Conditions of Concern A Hydrology and HydrauUc Report has been prepared for Toyota Carlsbad Service Facility, dated April 5,2005. As part of the drainage study, a field reconnaissance was conducted for this project. No detrimental effect was observed onsite. The existing outlet structure remains in good condition and no sign of erosion was observed. The potential of downstream erosion is minimal because the runoff from the development is proposed to be released into an existing storm drain in Avenida Encinas and the existing outlet structure remains in good condition. 2 Establish Permanent Storm Water Best Management Practices To address water quality for the project, permanent BMPs wiU be incorporated into the project design. Anticipated and potential poUutants of concern as noted in Table 2 wiU be addressed through four types of BMPs. These types of BMPs are Site Design, Source Control, BMPs for Individual Priority Project Categories and Treatment Control. A. Site Design BMPs Control post-development peak storm runoff discharge rates and velocities to maintain or reduce pre-development downstream erosion by applying the following concepts: • Increasing buUding density (multi-story building). • Driveways and parking lot aisles have been designed to meet the minimum width. • This project wiU not increase post-development runoff. B. Source Control BMPs Source control BMPs will consist of measures to prevent poUuted runoff. • Trash storage areas shall be paved with an impervious surface, designed not to allow run-on from adjoining areas, walled to prevent off-site transport of trash and contain attached Uds on all trash containers that exclude rain. Employ rain shutoff devices to prevent irrigation during and after precipitation; and use flow reducers or shutoff valves triggered by a pressure drop to control water loss in the event of broken sprinkler heads or lines. • Design irrigation systems to each landscape area's specific water requirements. • Provide concrete stamping, or equivalent, of all storm water conveyance system inlets and catch basins within the project area with prohibitive language (e.g., "No Dumping -1 Live Downstream".), satisfactory to the City Engineer. C. BMPs Applicable to Individual Priority Project Categories Dock Area: Loading/unloading dock areas shaU include the foUowing: (1) cover loading dock areas, or design drainage to preclude urban run-on and runoff; or (2) Direct connections to storm drains from depressed loading docks (truck weUs) are prohibited. Maintenance Bays: • Repair/maintenance bays are indoors. The discharges from the maintenance bays' will be pre-filtered and released into the sanitation system. Vehicle & Equipment Wash Areas: • Areas for washing/steam cleaning of vehicles and areas for outdoor equipment/accessory washing and steam cleaning is self-contained to preclude run- on and run-ofif, covered with a roof or overhang, and equipped with a clarifier or other pretreatment faciUty; (2) properly connected to a sanitation sewer if appropriate. Where areas are connected to a sanitary sewer, an Industrial Waste Permit may be required from the Encina Water PoUution Control FacUity. Surface Parking Areas: • Incorporate landscaping into drainage design when possible. Non-RetaU FueUng Areas • Not Applicable 2.3 Treatment Control BMPs The following treatment control BMPs wUl be implemented to address water quality. • Media Fihration Device (VortFilter by Vortechnics) VortFilter Cartridge is filled with PerUte, Granular Activated Carbon and ZroUte. VortFilter is capable of removing particles as small as 7 Microns at a flow rates ranging from 7.5 gpm to 20 gpm. Placement of the BMPs are noted on the WQTR Exhibit. 3 OPERATION AND MAINTENANCE PROGRAM The operation and maintenance requirement for each type of BMP is as foUows: 3.1 Maintenance Schedule and Cost for BMPs Media Filter (VortFUter by Vortechnics) Routine Action Maintenance Indicator Field Measurement Measurement/ Inspection Frequency Maintenance Activity Site-Specific Requirement Cost per fliter Inspect for sediment accumulation in Pre-treatment sedimentation chamber Sediment occupies 10% of the filter chamber volume Measure with appropriate device Annually in May $201.36 Remove sediment prior to wet season. Characterize sediment and properly dispose $970.32 Inspect for minor maintenance Per manufacture's guidelines None Annually Clean per manufacturer's guidelines. Prior to wet season. $201.36 Media Filter (VortFilter by Vortechnics) .S c 3 -2 O q ai < a o IB 'S '-o c o 3 3 O s £ i: 1^ o c v o D- .fa w 3 S g" K a! O a ia Manufacturer's recommended major maintenance Per manufacture's guidelines Per manufacture's guidelines Annually Consult with manufacturer regarding need for replacement of canisters. If manufacturer confirms need, replace canisters. Prior to wet season. When canisters are changed send canisters to manufacturer to determine reraaining life of the media $5375.88 (by contract and oversite) Inspection for trash and debris at inlet and outlet structures and with in vaults Trash/debris present Visual observation During routine trashing. Remove and dispose of trash and debris when on site conducting inspections. $0 Inspection for standing water Water accumulation in any structure or other location within the filter Standing water in any structure or other location within the filter Annually, at end of wet Gravity drain where possible. $0 If standing water can not be removed of remains through wet season notify VCD. $0 (Does not include Vector Control Agency costs) General Maintenance Inspection Inlet structures, outlet structures, vault, piping, or other features damaged and for graffiti or vandalism Visual observation Total Semi-Annually, late wet season. Consult engineer if immediate solution is not evident. Take corrective action prior to wet season. Consult engineer if immediate solution is not evident. $402.72 $7151.64 3.1 Numeric Sizing Calculation for BMPs For Flow Based BMPs: Q=CIA C=0.87 1=0.2 A=2.6 ac Q=(0.87)x(0.2)x(2.6) Q=0.45 cfs Use one cartridge Responsible Party Information: SteUar Properties 5424 Paseo Del Norte Carisbad, CA 92008 Bob Wolf 760-497-7286 4 REFERENCE Water Quality Control Plan for the San Diego Basin (9) California Regional Water Quality Control Board, San Diego Region, September 8,1994 County of San Diego, Standard Urban Storm Water Mitigation Plan for Land Development and PubUc Improvement Projects, February 2003 California Stormwater Best Management Practice Handbook, Municipal, March 1993 2002 CWA Section 303(d) List of Water Quality Limited Segment, February 2003 ^ Vortechnics* VortFilter TM TECHNICAL DESIGN MANUAL INCLUDING: DESIGN AND OPERATION INSPECTION AND MAINTENANCE LABORATORY TESTING DATA Committed to Clean Water™ Vortechnics, Inc. • 200 Er>terprlse Drive • Scarborough, ME 04074 phone 207.885.9830 • fax 207.885,9825 • toll free 877.907.8676 • web vortechnics.com VortFilter™ Design and Operation Basic Operation VortFilter™ is a v^^ater quality treatment device specifically engineered to address the most challenging stormwater applications. In many applications, particularly where nutrients, metals and high solids removal rates are mandated, water quality regulations cannot be met without addressing the pollutant load that is very fine (less than 35 microns) and/or neutrally buoyant. Such pollutants are difficult to remove with conventional gravitational separation. The VortFilter™ utilizes a proprietary media in a filter cartridge configuration to provide a physical barrier to the passage of such particles. Numerous deleterious effects have been linked to impervious surfaces associated with land development, including an increase in the amount and variety of pollutants. Federal, State and/or local regulations commonly require permanent post-construction pollution controls to reduce the impact of such development. Such facilities have historically included biofilters, infiltrating basins, sand filters and ponds and other land intensive treatment practices. In many cases, site constraints preclude the use of such land intensive treatment systems and an alternative water quality treatment device is required. The VortFilter™ is designed to meet this need by providing a high level of pollution control with minimal restrictions on site development options. The VortFilter™ incorporates gravitational separation and media filtration within a single below-grade unit. Stormwater enters the vault through the inlet pipe, which is located below the media cartridges. The cartridges are mounted in a precast concrete deck that confines untreated water below the cartridges. At flow rates up to the water quality flow, all water must flow up through the filter cartridges to reach the outlet. Once the water quality flow rate is exceeded, flow rates greater than the capacity ofthe cartridges will be bypassed through the overflow pipe. Gravitational separation occurs in the pretreatment sump below the deck, where flow velocities are low compared to those within the upstream collection system. Coarse sediment that enters the unit will settle in the sump beneath the filter cartridges. Oil and other floating materials will rise in the void spaces between the cartridges and be trapped beneath the filter cartridge deck. The distance between the bottom of the filter cartridge and the bottom of the vault is typically 18 inches, but may vary as necessary. This area is referred to as the sedimentation basin. Stormwater is forced through the media cartridges as head builds within the system. Fine particulate material is removed by filtration as it flows through the filter media. The treated water is discharged from the media cartridge outlets, onto the top of the filter deck and ultimately through the vault outlet. The VortFilter™ is currently available in multi-cartridge pre-cast vault and manhole configurations. Figure 1: Typical vault configuration VF.TDM.2.12.04 VortFilter^"^ The VortFilter™ is designed to treat stormwater runoff from new and existing impervious areas including: • Commercial and residential redevelopments where site constraints make above ground mitigation impractical or infeasible; • Highways, bridges and other transportation corridors where limited area within the right-of- way or easement is available for mitigation; • Sites where public safety concerns preclude the use of land based detention ponds; • High risk watersheds where reliable removal of metals, nutrients and fine sediments is required; • Where nuisance or dry weather flows must be treated to a high level; and • Where captured pollutants must be sequestered from the natural environment including the ground water table and surrounding soils. VortFilter™ Cartridge Components Me<tit Release Handle fiUM Housing Fitter Mftdia UMng Hmdte Filter Housing: Polypropylene m*<^m»omci casing holds the Vorti^ilter™ components. Lifting Handles: Allow for easy cartridge removal. Inner and Outer Media Screens: Fine mesh screens hold filter media in place. VortFilter™ Media: Custom selected media optimizes treatment for each site. Media Retention Plates: Retain filter media in the cartridge during normal operation and release during a maintenance event. The plates are hinged at the center above a pivot shaft that extends through the filter housing, and are held in the closed position by tabs located at two points along the perimeter ofthe filter housing. Inner Media r Media r«en Modla IIMnUon Plate Figure 2 Media Release Handles: Release the media retention plates when turned 90 degrees to the open position. Once the filter media is replaced, the handles are moved to the closed position. Applications and Filter Design Site Applications The number of cartridges contained within the VortFilter™ is flexible, which allows the system to be sized to meet the stormwater treatment requirements on a wide variety of sites. The VortFilter™ may also provide treatment for dry weather flows as long as sufficient bypass capacity is provided to accommodate wet weather flows. The VortFilter™ is typically installed below grade and will meet HS-20 loading requirements. VortFilter™ design is dictated by site parameters provided by the specifying engineer and local regulatory requirements. A copy of a typical specifier's worksheet is available online at www.vortechnics.com or from Vortechnics on request. Each VortFilter™ is typically designed to treat VortFilter™ Technical Design Manual VF.TDM .2.12.04 VortFilter™ a water quality flow rate before any flow is bypassed. The system will also be designed to pass the peak flow rate for the collection system. Depending on the performance objectives for the VortFilter™ and the filter media selected, the crest ofthe standpipe will be located such that each filter will treat between 12 and 20 gallons before bypass. For example a system may be configured to treat 20 gpm per cartridge at 20" of head loss when filled with HP periite. This system will be expected to remove 80% ofthe TSS load based on laboratory removal rates for Sil-Co-Sil 250. Determining VortFilter™ Cartridge Quantity Filter cartridge media is custom designed based on pollutant removal targets and site constraints. If the rate of runoff from the developed site is not controlled upstream of the VortFilter™, the number of cartridges required is likely to be governed by the maximum flow rate associated with the water quality design storm. Placement of the VortFilter™ downstream of flow control devices and/or storage facilities may reduce peak flow rates to the system and thereby reduce the number of cartridges required. Although this configuration is also likely to decrease the load of pollutants reaching the filter, pollutant accumulation may be the limiting design criteria instead of flow rate per cartridge. Installation of a swirl concentrator such as the Vortechs® System or the VortSentry™ may be desired upstream ofthe VortFilter™ to decrease the pollutant load reaching the filter, thereby improving performance and reducing maintenance requirements. Conveyance Capacity The VortFilter™ is designed to bypass the portion of incoming flow that exceeds the water quality flow rate through the standpipe located in the deck. The diameter of this pipe is equal to or greater than the diameter of the inlet to the system. This capacity combined with the capacity of the filters will be sufficient to ensure that the VortFilter™ will not be a hydraulic restriction in the event of a major storm. Alternatively bypass capacity can be provided externally. Treatment Processes The VortFilter™ is a stormwater treatment system that is particularly suited for removal of extremely fine particulate (e.g. less than 50 microns in diameter) from water. The system combines the following physical treatment principles and processes within a single water quality device: A. Sedimentation - Below the filter deck, gravitational separation of solids with a density greater than that of water occurs. A reduction in settleable solids concentration typically corresponds to a reduction in concentrations of organics, nutrients, metals and other pollutants. B. Flotation - Below the filter deck, gravitational separation of particles with densities less than that of water such as dispersed oil droplets occurs. Most hydrocarbon compounds not soluble in water have densities less than water and thus are removed by such separation. C. Filtration - The periite particles in each cartridge provide a physical barrier to the passage of very fine particulate matter. The porous nature of periite creates very low velocities in the interstitial pore spaces of the filter where particles may settle or become physically trapped VF.TDM.2.12.04 VortFilter™ Treatment System Configuration - System Hydraulics Treatment flow rate As stormwater enters the treatment sump below the filter cartridge deck, gravitational separation occurs. Oils and floating pollutants rise upward to remain within the space between the cartridges and a fraction of the total suspended solids settles to the bottom of the sump. Stormwater is forced through the media cartridges as head builds within the system. As stormwater flows through the filter media, fine particulates are removed by filtration. Treated water is discharged from the media cartridge outlets, onto the top of the fliter cartridge deck and ultimately out through the vault outlet. Flows exceeding the water quality flow rate If no external bypass structure is utilized to divert fiows exceeding the water quality fiow rate, flows exceeding the treatment flow rate will pass through the overflow pipe and on to the ouflet. This pipe is sized to allow the peak fiow rate expected in the upstream drainage system to flow through the VortFilter™ without restriction. The height of this pipe is set to allow the water quality flow rate to be treated before bypass. If an upstream treatment system is utilized, the bypass may be incorporated into that system. An overflow pipe will still be installed, but primarily for maintenance purposes. Filtration The filtrafion process begins when the collected water is hydrostatically forced upward through the filter media cartridge. The VortFilter™ cartridge is filled with customized media that prevents the passage of sediment and other fine particulates and the pollutants associated with them. Filter media is conflned by a fine mesh screen and has a minimum bed depth of 7-inches. VortFilter™ Media Vortechnics offers a variety of media for targeting specific pollutants. These media can be used individually or in combinafion within each cartridge. Media Opfions: • Periite Periite is a lightweight, inert material commonly used as a stormwater filtration media. It is a volcanic rock, which expands when heated to approximately 1600°F (870°C), creating a three dimensional, porous media. The media forms a highly effective filter matrix. Periite is capable of removing very fine particles, as well as associated nutrients, metals, and oil and grease. • Granular Activated Carbon (GAC) GAC is manufactured by charring organic materials (wood, peanut hulls, coconut shells, coal, etc.). Activating the charred material involves exposure to an oxidizing gas, typically steam, at high temperatures. The process adds a charge to the extensive surface area of the carbon (125 acres (50.6 hectares) of surface area per pound of GAC), spawning one of the most effective filter media on earth. This media has been used for many decades in the water and wastewater industries to remove contaminants such as organics, pesticides, herbicides, and hydrocarbons. GAC is also capable of removing heavy metals from aqueous solutions, and modified forms have the ability to reduce bacteria concentrations. • Zeolite Zeolite is a porous alumino-silicate mineral formed from volcanic ash. Clinoptilolite is the VF.TDM.2,12.CI4 VortFilter™ typical zeolite structure used in stormwater flitration due to its high cation exchange capacity (CEC). A large body of-research has been developed documenting the ability of zeolite to remove both dissolved metals and ammonium from stormwater runoff. Cartridge Installation A Vortechnics representative will install the cartridges in the system upon completion and stabilization of the site, typically three to four months after installation of the precast structure. Sediment loads transported during construction are typically much greaterthan after site stabilization. These sediments are best controlled with good housekeeping practices and erosion control products. Post construction installation will prevent the cartridges from being inundated with sediment mobilized during construction. This will eliminate the need for cartridge maintenance before the site is completed. The site contractor must certify that the storm sewer system is free of sediment and debris and that adequate access is provided prior to installation of the cartridges. Inspection and Maintenance Once the cartridges are installed, inspection should be conducted quarterly during the first two years of operation. Based on observations during this period, a long-term maintenance schedule can be developed. The VortFilter™ is generally designed to require maintenance no more frequentiy than once a year. Routine Inspection 1. Open the main hatchway. Allow fresh air to ventilate the unit for at least 10 minutes. 2. Using a portable floodlight, examine the top of tiie filter deck from the outside of the unit. Note any accumulation of material on top of the deck. Visually examine the fliter cartridge tops to confirm that all filters are still soundly fastened to the filter deck. 3. If there Is a significant amount of accumulated material on the fliter deck, or if any of the filter cartridges appear in need of replacement, a complete maintenance event should be scheduled. 4. With a graduated rod, measure the sediment accumulation in the sedimentation basin through the overflow pipe. If the level of sediment is greater than 6 inches, a complete maintenance event should be scheduled. 5. Accomplish the repair or cleaning as needed, and return the unit to operation. 6. Fill out the VortFilter™ inspection log. A sample log is included in Appendix A. Maintenance The VortFilter™ will require periodic filter replacement and sedimentation basin cleanout with a vacuum truck. Maintenance inten/als will be site-specific, but systems will typically be sized to only require maintenance once or twice per year based on anticipated loading rates. Good housekeeping practices upstream of the VortFilter™ can significantiy extend cartridge life. For example, sweeping paved surfaces, collecting leaves and grass trimmings and minimizing the exposure of unconsolidated sediments to the elements will reduce loading to the system. Installation of a Vortechs System® or a VortSentry™ upstream ofthe VortFilter™ will also extend the interval between maintenance events. Typically, the maintenance procedure involves dumping the spent filter media from the cartridge into the sedimentation basin where it may be removed by vacuum truck along with the settled sediment and remaining liquid. Only the lightweight, empty cartridges are removed from the VortFilter™ vault. This significant labor saving feature is unique to the VortFilter™. VortFilter™ Technical Design Manual 6 VF.TDM.2.I2.04 VortFilter™ When it is determined that filter maintenance is required, either a representative from Vortechnics can perform the routine maintenance and cartridge replacement, or the following simple procedure can be followed by a representative of the owner. Recommended Equipment and Supplies • Caution tape, orange cones, or other means of securing the job site from pedestrian and vehicle traffic; • Confined space entry equipment, including but not limited to: personnel harnesses, tethers, and rescue winch and atmospheric tester; • Standard industrial vacuum truck, accessories, and operator; • Portable flood lights (high powered flashlights); • Water hose and source of water; • Work clothes, gloves, rubber boots; • Shovels; • Tool for lifting manhole covers and opening access hatches; and • VortFilter™ Maintenance Log VortFilter^" Technical Design Manual VF.TDM.2.12.04 VortFilter™ Recommended Maintenance Procedure 1. Contact Vortechnics at 207-885-9830 to order replacement cartridges and gaskets. 2. Prepare the job site by protecting the unit from any pedestrian or vehicle traffic, or site- specific interferences. Obtain necessary safety equipment such as confined space entry equipment, etc. Set up a vacuum truck close to the unit. Have replacement cartridges delivered to the site. It will be helpful to have a source of water available for cleaning the filters. To allow efficient dewatering ofthe system, maintenance should be perfonned during dry weather conditions. 3. Once on-site with a vacuum truck, replacement cartridges and gaskets, open system hatches and manhole covers and allow system to air out for at least 10 minutes. 4. Visually inspect the top half of the VortFilter™ unit. If there is standing water or debris that can be removed, do so at this time. 5. Dewater the system through the overflow pipe until the water level drops below the bottom of the cartridges (Figure 3). Figure 3 In accordance with applicable confined space entry procedures, enter the unit and release the media retention plates holding the fliter media in the cartridge by turning the handles on top of the filter cartridges to the open position (Figure 4). The filter media will fall from the cartridge into the sedimentation basin. Figure 4 VortFilter™ Technical Design Manual VF.TDM.2.12.04 VortFilter™ 7. Unclamp cartridges from the filter deck and remove through the manholes. Also remove the cartridge gaskets. 8. Clear any debris from the top of the filter deck. 9. Vacuum filter media and accumulated solids from the sedimentation basin through cartridge holes, jetting as necessary to fluidize the material (Figure 5). This area should be easily accessible once the cartridges have all been removed. Figure 5 10. After the entire unit has been cleaned, perform a basic inspection ofthe concrete structure, inlet and outlet connections, and overflow pipe. Note any damage to the components, and repair as necessary. 11. Replace spent carfi-idges and gaskets with new pre-packed cartridges and gaskets provided by Vortechnics. 12. Clamp the new cartridge into place ensuring that the gasket is seated evenly between the cartridge and the basin deck. 13. Close the hatches and replace manhole covers. 14. Dispose of the material removed from the VortFilter™ in accordance with applicable regulations. 15. Fill out the VortFilter™ Cartridge Maintenance Log. Sample logs are included in Appendix B. Alternative Maintenance Procedure An alternative method of maintaining the VortFilter™ is to re-use the cartridges that are currently at the site and refill each cartridge individually with a Vortechnics supplied fliter media. After completing step 10 in the previous protocol, complete the following steps: 1. Power wash empty cartridges. 2. Invert empty cartridge and refill with the specified Vortechnics filter media. 3. Close the media retention plates, turning the tabs to the closed position. 4. Remove the old gasket from each cartridge and place a new gasket around the rim of the refurbished cartridges and reinstall in the filter deck. VF.TDM.2.12.04 VortFilter™ Appendix A VortFilter™ Inspection Log Model: Number of Cartridges:. Location: Date Inspector Description of debris on top of filter basin deck Observed condition of cartridge tops Observed sediment accumulation in sedimentation basm ^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^ -. • • • ^^^^^^^^^^^^^^^ VortFiiter^" Technical Design Manual 10 VF.TDM.2.12.04 VortFilter™ Appendix B VortFilter™ Maintenance Log Model: Number of Cartridges: Location: Date: Start Time: End Time: Inspector:. Other Personnel: Media Months in Service Nuinber of Filters Recharged Type of Media Used for Recharge List of Safety Equipment and Procedures Used- Description of Debris on Top of Filter Basin Deck: Observed Condition of Cartridges Observed Sediment Accumulation in Basin: Observed Condition of Structure: Repairs Completed: Comments VortFilter Technical Design Manual 11 VF.TDM.2.12.04 ATTACHMENT "A" VICINITY MAP foi, li-0 ^A/^MMs HAQ SFTE O KEY TO REGION on ONTROL BOARD Gi^^ I L, Jib .y?; '^Y-xQr Pit Filtratig/ pla;lt .)ajEucaiyptiJSr- Itu i I ^ Missio i Beacii lp Exposed W«l(0 ATTACHMENT "B' SITEMAP ATTACHMENT "C" STORM WATER REQUIREMENTS APPLICABILITY CHECKLIST storm Water Standards 4/03/03 VI. RESOURCES & REFERENCES APPENDIXA STORM WATER REQUIREMENTS APPLICABILITY CHECKLIST Complete Sections 1 and 2 of the following checklist to determine your project's permanent and construction storm water best management practices requirements. This form must be completed and submitted with your permit application. Section 1. Permanent Storm Water BMP Requirements: If any answers to Part A are answered "Yes," your project is subject to the "Priority Project Permanent Storm Water BMP Requirements," and "Standard Permanent Storm Water BMP Requirements" in Section 111, "Permanent Storm Water BMP Selection Procedure" in the Storm Water Standards manual. If all answers to Part A are "No," and any answers to Part B are "Yes," your project is only subject to the "Standard Permanent Storm Water BMP Requirements". If every question in Part A and B is answered "No," your project is exempt from permanent storm water requirements. Does the project meet the definition of one or more of the priority project categories?* Yes No 1. Detached residential development of 10 or more units X 2. Attached residential development of 10 or more units X 3. Commercial development qreater than 100,000 square feet X 4. Automotive repair shop 5. Restaurant X 6. Steep hillside development greater than 5,000 square feet % 7 Project discharqinq to receivinq waters within Environmentally Sensitive Areas X 8. Parking lots greaterthan or equal to 5,000 ft^ orwith at least 15 parking spaces, and potentially exposed to urban runoff 9. Streets, roads, highways, and freeways which would create a new paved surface that is 5.000 sauare feet or qreater -A * Refer to the definitions section in the Storm Water Standards for expanded definitions of the prionty project cateqories. Limited Exclusion: Trenching and resurfacing work associated with utility projects are not considered priority projects. Parking lots, buildings and other structures associated with utility projects are priority projects if one or more of the criteria in Part A is met. If all answers to Part A are "No", continue to Part B. 30 storm Water Standards 4/03/03 Part B: Determine Standard Permanent Storm Water Requirements Does the project propose: Yes No 1. New impen/ious areas, such as rooftops, roads, parking lots, driveways, paths and sidewalks? X 2, New pervious landscape areas and irrigation systems? X 3. Permanent structures within 100 feet of any natural water body? 4. Trash storage areas? 5. Liquid or solid material loading and unloading areas? 6. Vehicle or equipment fueling, washing, or maintenance areas? 7. Require a General NPDES Permit for Storm Water Discharges Associated with Industrial Activities (Except construction)?* 8. Commercial or industrial waste handling or storage, excluding typical office or household waste? 9. Any grading or ground disturbance during construction? X 10. Any new storm drains, or alteration to existing storm drains? X *To find out if your project is required to obtain an individual General NPDES Permit for Storm Water Discharges Associated with Industrial Activities, visit the State Water Resources Control Board web site at, www.swrcb.ca.gov/stormwtr/industrial.html Section 2. Construction Storm Water BMP Requirements: If the answer to question 1 of Part C is answered "Yes," your project is subject to Section IV, "Construction Storm Water BMP Performance Standards," and must prepare a Storm Water Pollution Prevention Plan (SWPPP). Ifthe answer to question 1 is "No," but the answer to any of the remaining questions is "Yes," your project is subject to Section IV, "Construction Storm Water BMP Pert'ormance Standards," and must prepare a Water Pollution Control Plan (WPCP). If every question in Part C is answered "No," your project is exempt from any construction storm water BMP requirements. If any of the answers to the questions in Part. C are "Yes," complete the construction site prioritization in Part D, below. Part C: Determine Construction Phase Storm Water Requirements. Would the project meet any ofthese criteria during construction? Yes No 1. Is the project subject to California's statewide General NPDES Permit for Storm Water Discharges Associated With Construction Activities? X 2. Does the project propose grading or soil disturbance? X 3. Would storm water or urban runoff have the potential to contact any portion of the construction area, includinq washing and staqing areas? X 4. Would the project use any construction materials that could negatively affect water quality if discharged from the site (such as, paints, solvents, concrete, and stucco)? X 31 storm Water Standards 4/03/03 Part D: Determine Construction Site Priority In accordance with the Municipal Permit, each construction site with construction storm water BMP requirements must be designated with a priority: high, medium or low. This prioritization must be completed with this form, noted on the plans, and included in the SWPPP or WPCP. Indicate the project's priority in one of the check boxes using the criteria below, and existing and surrounding conditions of the project, the type of activities necessary to complete the construction and any other extenuating circumstances that may pose a threat to water quality. The City reserves the right to adjust the priority of the projects both before and during construction. [Note: The construction priority does NOT change construction BMP requirements that apply to projects; all construction BMP requirements must be identified on a case-by-case basis. The construction priority does affect the frequency of inspections that will be conducted by City staff. See Section IV.1 for more details on construction BMP requirements.] ^ A) High Priority 1) Projects where the site is 50 acres or more and grading will occur during the rainy season 2) Projects 5 acres or more. 3) Projects 5 acres or more within or directly adjacent to or discharging directly to a coastal lagoon or other receiving water within an environmentally sensitive area Projects, active or inactive, adjacent or tributary to sensitive water bodies Q B) Medium Priority 1) Capital Improvement Projects where grading occurs, however a Storm Water Pollution Prevention Plan (SWPPP) is not required under the State General Construction Permit (i.e., water and sewer replacement projects, intersection and street re-alignments, widening, comfort stations, etc.) 2) Permit projects in the public right-of-way v/here grading occurs, such as installation of sidewalk, substantial retaining walls, curb and gutter for an entire street frontage, etc. , however SWPPPs are not required. 3) Permit projects on private property where grading permits are required, however, Notice Of Intents (NOIs) and SWPPPs are not required. • C) Low Priority 1) Capital Projects where minimal to no grading occurs, such as signal light and loop installations, street light installations, etc. 2) Permit projects in the public right-of-way where minimal to no grading occurs, such as pedestrian ramps, driveway additions, small retaining walls, etc. 3) Permit projects on private property where grading permits are not required, such as small retaining walls, sfrrgle-family homes, small tenant improvements, etc. 32