STORM WATER POLLUTION PREVENTION PLAN

City of Lathrop 390 Towne Center Dr. Lathrop, CA 95330

STORM WATER POLLUTION PREVENTION PLAN

City of Lathrop 390 Towne Center Dr. Lathrop, CA 95330

TABLE OF CONTENTS

STORM WATER POLLUTION PREVENTION PLAN 1.0

INTRODUCTION .............................................................................................................................................. 1

2.0

PLANNING AND ORGANIZATION .............................................................................................................. 2

2.1 3.0

POLLUTION PREVENTION TEAM ........................................................................................................................ 2 SITE MAPS......................................................................................................................................................... 3

3.1 CITY DRAINAGE ZONES..................................................................................................................................... 3 3.1.1 Zone 1 - Direct Discharge to the San Joaquin River................................................................................. 3 3.1.2 Zone 2 - Retained within the Drainage Zone............................................................................................ 3 3.2 TABULATED MAP LIST ...................................................................................................................................... 3 4.0

LIST OF SIGNIFICANT MATERIALS.......................................................................................................... 4

5.0

DESCRIPTION OF POTENTIAL POLLUTANT SOURCES ...................................................................... 5

5.1 INDUSTRIAL PROCESSES .................................................................................................................................... 5 5.1.1 Wells 6, 8, 9, and 21 ................................................................................................................................. 5 5.1.2 Well 7 Site ................................................................................................................................................ 6 5.1.3 Water Tanks Booster Stations .................................................................................................................. 6 5.1.4 Storm Water Lift Stations......................................................................................................................... 7 5.1.5 Corporate Yard ......................................................................................................................................... 7 5.1.6 Sewer Lift Stations ................................................................................................................................... 8 5.2 MATERIAL HANDLING AND STORAGE AREAS ................................................................................................... 8 5.3 DUST AND PARTICULATE GENERATING ACTIVITIES .......................................................................................... 9 5.4 SIGNIFICANT SPILLS AND LEAKS ....................................................................................................................... 9 5.5 NON-STORM WATER DISCHARGES .................................................................................................................... 9 5.6 SOIL EROSION ................................................................................................................................................. 10 6.0

ASSESSMENT OF POTENTIAL POLLUTANT SOURCES ..................................................................... 11

6.1 NARRATIVE ASSESSMENT ............................................................................................................................... 11 6.1.1 Likely Pollutants..................................................................................................................................... 11 6.2 TABULATED OVERVIEW OF LIKELY POLLUTION SOURCES .............................................................................. 11 6.3 OPERATIONS SUMMARY .................................................................................................................................. 12 7.0

STORM WATER BEST MANAGEMENT PRACTICES (BMPS)............................................................. 13

7.1 NON-STRUCTURAL BMPS ............................................................................................................................... 13 7.1.1 Good Housekeeping ............................................................................................................................... 13 7.1.1.1 7.1.1.2 7.1.1.3 7.1.1.4 7.1.1.5 7.1.1.6

7.1.2 7.1.3 7.1.4 7.1.4.1

Wells 6, 8, 9, and 21.............................................................................................................................................13 Well 7 Site............................................................................................................................................................13 Water Tanks and Booster Stations .......................................................................................................................14 Storm Water Lift Stations ....................................................................................................................................14 Corporate Yard.....................................................................................................................................................15 Sewer Lift Stations...............................................................................................................................................15

Preventative Maintenance....................................................................................................................... 15 Spill Prevention and Response ............................................................................................................... 15 Material Handling and Storage ............................................................................................................... 16 Municipal Water Line Flushing/Potable Water Source Discharges .....................................................................16

7.1.5 Employee Training ................................................................................................................................. 16 7.1.6 Waste Handling/Recycling ..................................................................................................................... 16 7.1.7 Record Keeping and Internal Reporting ................................................................................................. 17 7.1.8 Erosion Control and Site Stabilization.................................................................................................... 17 7.1.9 Inspections.............................................................................................................................................. 17 7.1.10 Quality Assurance................................................................................................................................... 18 7.2 STRUCTURAL BMPS ........................................................................................................................................ 18 7.2.1 Overhead Coverage ................................................................................................................................ 18 Page i

TABLE OF CONTENTS 7.2.2 Retention Basins ..................................................................................................................................... 18 7.2.3 Control Devices ...................................................................................................................................... 19 7.2.4 Secondary Containment Structures......................................................................................................... 19 7.2.5 Treatment................................................................................................................................................ 19 7.3 TABULATED DESCRIPTIONS............................................................................................................................. 20 8.0

ANNUAL COMPREHENSIVE SITE COMPLIANCE EVALUATION (ACSCE)................................... 25

8.1 8.2 8.3

VISUAL INSPECTION OF POTENTIAL POLLUTANT SOURCES SITE DRAINAGE ................................................... 25 REVIEW AND EVALUATION OF THE BMPS ....................................................................................................... 25 ACSCE INSPECTOR ......................................................................................................................................... 25

9.0

SWPPP CHANGES.......................................................................................................................................... 26

10.0

CERTIFICATION AND SIGNATURE ......................................................................................................... 27

Figures Figure 1—Vicinity Map Figure 2—Topographic Drainage Map Figure 3—Public Works Department & Park Maintenance Organizational Chart

Acronyms ACSCE—Annual Comprehensive Site Compliance Evaluation ASTs—Aboveground Storage Tanks BMPs—Best Management Practices NPDES—National Pollutant Discharge Elimination System SWPPP—Storm Water Pollution Prevention Plan O&M—Operations and Maintenance

Page ii

SWPPP REVISIONS Revision No.

Date

0

4/5/2008

Revised By Aaron Ortiz WGR Southwest, Inc.

Page iii

Reason for Revision

Sections Revised

Initial Preparation

All New

SWPPP ANNUAL REVIEW Date

Name of Reviewer

Signature

Page iv

SWPPP DISTRIBUTION

1. City of Lathrop Public Works Department 390 Towne Centre Drive Lathrop, CA 95330 2. City of Lathrop Operation and Maintenance Division 15755 Seventh Street Lathrop, CA 95330 3. WGR Southwest, Inc 315 W. Pine St., Suite 8 Lodi, CA 95240

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City of Lathrop Storm Water Pollution Prevention Plan Version 0

1.0

Introduction

This document constitutes the Storm Water Pollution Prevention Plan (SWPPP) for activities performed by the Public Works Department of the City of Lathrop (Lathrop). Lathrop is located south of the City of Stockton, near the junction of I-5, Highway 205, and Highway 120, in Northern California (see Figure 1). Operation and Maintenance activities performed by Lathrop do not require coverage under the Industrial General Permit for storm water discharges in Attachment 1, of the State of California National Pollutant Discharge Elimination System (NPDES) Permit for Discharges of Storm Water Associated with Industrial Activities (General Permit); however, Lathrop, in an effort to document implemented Best Management Practices (BMPs) and protect storm water quality has created this SWPPP. All terms in this document (i.e. authorized, unauthorized, discharge, outfall, etc.) are modeled after Section A of the General Permit (97-03-DWQ). The principal objectives of this plan are to: •

Identify and evaluate sources of pollutants associated with industrial activities that may affect the quality of storm water discharges and authorized nonstorm water discharges from Lathrop Operation and Maintenance activities.

•

Identify and implement site-specific best management practices (BMPs) to reduce or prevent pollutants associated with industrial activities in storm water discharges and authorized non-storm water discharges.

This plan is reviewed on an annual basis during the General Permit-modeled Annual Comprehensive Site Compliance Evaluation (ACSCE). This evaluation is described in detail in Section 8 of this plan. Any revisions to the plan are recorded on the page titled “SWPPP Revisions” located in this document immediately after the table of contents. Each annual review is recorded and signed by the reviewer on the page titled “SWPPP Annual Review” located in this document immediately after the above-mentioned annual review page.

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City of Lathrop Storm Water Pollution Prevention Plan Version 0

2.0

Planning and Organization

Lathrop has incorporated a team approach to prevent pollution of storm water discharges. The team is comprised of members of Lathrop’s Public Works Department management and staff, as well as, an environmental contractor on an as-needed basis. However, every employee is trained to have an active role in preventing pollution of storm water runoff and eliminating unauthorized non-storm water discharges. 2.1

Pollution Prevention Team

Table 2.1 lists the Lathrop storm water pollution prevention team members along with their area of responsibility. Table 2.1 is subject to changes in employees and responsibilities and is reviewed and updated on an annual basis. For a complete outline of Lathrop Public Works and Park Maintenance Departments personnel organizational structure, please see Figure 3. Table 2.1 Pollution Prevention Team Name

Title

Telephone No.

Kirk Cloyd

Operations & Maintenance Superintendent

(209) 941-7430 ext. 7475

Public Works

Engineering

(209) 941-7200

Staff Members

Operations & Maintenance Department Employees

(209) 941-7463

John Teravskis

WGR Southwest, Inc

(209) 334-5363 ext. 202

Page 2

Responsibility Certification of SWPPP and reports. Implementation of the city’s pollution prevention efforts. Assists implementation of the city’s’ pollution prevention efforts. Assists implementation of the city’s pollution prevention efforts. Assists Lathrop on an as-needed basis.

City of Lathrop Storm Water Pollution Prevention Plan Version 0

3.0

Site Maps

3.1

City Drainage Zones

Lathrop has two main drainage zones; Zone 1 and Zone 2. 3.1.1

Zone 1 - Direct Discharge to the San Joaquin River

All water that flows into the City’s storm drains in Central Lathrop, Mossdale Village, Historic Lathrop, and the Crossroads Business Park discharges directly to the San Joaquin River. This includes nuisance flows and low and high storm water flows. (Nuisance flows are defined as non-storm water discharges from a variety of sources (see Figure 2). 3.1.2

Zone 2 - Retained within the Drainage Zone

Low and nuisance flows in the River Islands, Richland, and Lathrop Industrial zones are captured and retained within those zones. High flows from significant storm water events are usually kept within the drainage zone, but in case of extended or very heavy rains, surface flow may ultimately reach the San Joaquin River by overflowing into another drainage zone (see Figure 2). 3.2

Tabulated Map List

Table 3.2 lists the maps that contain various areas covered by this SWPPP. Table 3.2 Maps Figure No.

Location

Vicinity Map

Figure 1

Included in Figures section of the SWPPP

Topographic Drainage Map

Figure 2

Included in Figures section of the SWPPP

Map Requirement

Map Name

This map shows the location and surrounding area of the City of Lathrop. This map depicts at least one quarter mile vicinity around the City of Lathrop, including nearby bodies of water, City of Lathrop outfalls, and drainage areas.

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4.0

List of Significant Materials

The following is a listing of the waste materials and materials used for operation and maintenance activities in Lathrop. Significant Material / Estimated Quantity per site Gasoline Two to three 5 gal. containers per site Diesel Fuel One 85-500 gal. double walled tank per site Food Grade Hydraulic Fluid 55 gal. (Drum)- Storage & 1 gal. Trash gates Motor Oil 55 gal. (Drum) Waste Oil 55 gal. (Drum) Roundup Pro Herbicide 10- 30 gal. (Drums) Sodium Hypochlorite Solution Twelve 5 gal. totes (Booster Stations) & One 30 gal. Drum (Wells) Maintenance and Cleaning Materials (Various small containers of lubricants, paints, and cleaning products)

Location Well 7 and Corporate Yard

Potential Pollutants Petroleum hydrocarbons

Large Storm Water and Sewer Lift Stations, Wells, and Booster Stations

Petroleum hydrocarbons

Large Storm Water Lift Stations, Well 7, and Corporate Yard

Oil and Grease

Well 7 and Corporate Yard

Oil and Grease

Well 7 and Corporate Yard

Oil and Grease

Well 7

Herbicide

Wells, Booster Stations, Well 7, and Corporate Yard

Chlorine

Well 7 and Corporate Yard

Oil and Grease, paints, detergents, and solvents

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City of Lathrop Storm Water Pollution Prevention Plan Version 0

5.0

Description of Potential Pollutant Sources

The Public Works Department is the largest department within the City of Lathrop. The Operation and Maintenance Division (O&M Division) of the Public Works Department, has the responsibility of implementing all operation and maintenance activities for Lathrop. The O&M Division activities include, but are not limited to; public streets, street trees, traffic systems, street lights, parks, city buildings, and graffiti removal. The O&M Division also operates and maintains the water wells, treatment facilities, the wastewater collection system, reclaimed water ponds, detention and retention storm water ponds, water distribution system, recycled water system, and storm water drainage systems, within the city. The O&M Division administration building is located at 15755 Seventh Street. The O&M Division office building has a city yard where mobile equipment and vehicles are parked; however, the Well 7 warehouse, storage containers and yard are where the majority of city equipment, mobile equipment, and maintenance materials and chemicals are stored. Due to the possibility of theft or vandalism, pollutants have the potential to come into contact with storm water at Lathrop properties. As a precaution, Lathrop has installed computerized camera systems, which take and record pictures at every groundwater well, booster station, sewer, and storm water lift station site. Each site also has another computer system which sends radio signals to the O&M Division administration building. Both systems are in place to monitor equipment function and site activity. Lathrop continually strives to eliminate or minimize the likelihood of potential pollutant sources. The following summarizes the potential sources of storm water pollutants. 5.1

Industrial Processes

5.1.1

Wells 6, 8, 9, and 21

Wells 6, 8, 9, and 21 each consist of a groundwater pump housed in a structure, a back-up generator to power the pump in the event of a power failure, and a chlorinator for well and water treatment. Groundwater from the well is chlorinated at the well and then is pumped to one of four aboveground water tanks for potable water storage and distribution.

Well 6

Potential pollutants include petroleum hydrocarbons from spills of diesel fuel during generator refueling, oil and grease from pump and generator maintenance, and chlorine from water treatment.

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5.1.2

Well 7 Site

Well 7 is similar to the other Lathrop groundwater wells but the property where Well 7 is located is Lathrop’s primary Operations and Maintenance Yard. The Well 7 site property has approximately 95 % permeable surface. The Well 7 site contains storage containers (used for parts, equipment, and hazardous materials storage) and a warehouse (used for parts, equipment, hazardous Well 7 materials, hazardous waste storage, equipment maintenance and minor mobile equipment maintenance). A minimal amount of gasoline and gasoline mixture fuel is stored on site for use in small and hand held equipment. Mobile equipment and vehicles are fueled at a nearby Warehouse at Well 7 site Lathrop-Manteca Fire District Fire Station. The Well 7 sites’ outside area is used for stockpiling Operation and Maintenance parts, city vehicles, equipment, mobile equipment and asphalt for road pothole repair. Lathrop maintains two trash bins at the Well 7 site, adjacent to the north perimeter fence. When the trash bins are at full capacity, Lathrop will temporarily stockpile non-hazardous materials Maintenance Hazardous (vegetative waste) west of the trash bins until the trash Materials container bins have been emptied. Materials listed in Section 4.0 are stored at the Well 7 site. Potential pollutants include petroleum hydrocarbons from, gasoline and gasoline mixture storage, and spills of diesel fuel during generator refueling; oil and grease from food grade hydraulic fluid leaks, motor oil, used waste motor oil, fluids and metals from parked vehicles and mobile equipment, various lubricants used in maintenance; herbicide from Roundup Pro, chlorine from water treatment paint and detergents from maintenance materials. 5.1.3

Water Tanks Booster Stations

Pete Freire AST

Lathrop has four aboveground storage tanks (ASTs) with accompanying Booster Stations. The ASTs contain treated ground and surface water and the Booster Stations consists of water pumps Page 6

Pete Freire Booster Station

City of Lathrop Storm Water Pollution Prevention Plan Version 0

and a chlorinator, for well and surface water treatment. The water pumps, chlorinator and back-up generator (to power the pumps in the event of a power failure) are housed in a structure near the AST. The treated potable water is pumped into the ASTs for storage, and then pumped out for use. Potential pollutants include petroleum hydrocarbons from spills of diesel fuel during generator refueling; oil and grease from pump, backup generator maintenance, and chlorine from water treatment. 5.1.4

Storm Water Lift Stations

There are two different types of Storm Water Lift Stations; small and large. The smaller lift stations consist of electrically powered sump pumps that pump effluent to one of six lager Storm Water Lift Stations. The larger Storm Water Lift Stations (M1-M6) consists of a structure that houses sump pumps, a back-up generator to power the pumps, in the event of a power Storm Water Lift Station failure, and a “trash gate.” Out M3 side the structure is a Vortex Separator to remove suspended solids and attached pollutants. Storm water enters the larger Storm Water Lift Stations where a trash rake machine collects larger debris and extracts it from the storm water for proper disposal (see Section 7.2.5). The storm water is then sump pumped through a Vortex Separator to one of four outfalls along the San Joaquin River. Potential pollutants include petroleum hydrocarbons from spills of diesel fuel during generator refueling; oil and grease from food grade hydraulic fluid leaks, oil and grease from pump and generator maintenance. 5.1.5

Trash Rake

Corporate Yard

The Corporate Yard site consists of the O&M Division, administration building, a small storage structure, and a partially paved lot. The Corporate Yard is primarily used for city vehicles and mobile equipment parking. As with the Well 7 site, no mobile equipment maintenance is performed onsite, with Corporate Yard the exception of occasional oil changes. A minimal amount of gasoline and gasoline mixture fuel is stored on site for use in small and hand held equipment. Mobile equipment and Mobile Equipment vehicles are fueled offsite. Page 7

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Potential pollutants include petroleum hydrocarbons from gasoline and gasoline mixture storage, oil and grease from parked vehicles and mobile equipment; fluids and metals from parked vehicles and mobile equipment, suspended solids from windblown, roadway dust, and the unpaved area of the lot. 5.1.6

Sewer Lift Stations

Mossdale Sewer Lift Station

Lathrop has a series of sanitary sewer lift stations (Sewer Lift Stations). The larger Sewer Lift Stations consist of a structure that houses an electric sump pump. Outside the structure there is a backup generator. The smaller Sewer Lift Stations consist of an electric pump. The Sewer Lift Stations convey sanitary sewer effluent to one of two treatment plants.

Potential pollutants include petroleum hydrocarbons from spills of diesel fuel, during generator refueling at the larger Sewer Lift Stations, oil and grease from pump and generator maintenance, and raw sewage from a sewer system back-up. 5.2

Material Handling and Storage Areas

Sewer Lift Station at the Lathrop-Manteca Fire District East Station

The handling of the significant materials listed in Section 4.0 is conducted in four primary areas of Lathrop. The following is a list of the areas where significant materials are handled: •

Well 7 Site The majority of significant materials handled by Lathrop are stored inside or under cover at the Well 7 warehouse, in storage containers. The Well 7 site property is used for O&M Division parts and equipment storage, as well as vehicles and mobile equipment parking. Asphalt for pothole repairs is stockpiled in the center of the Well 7 site.

•

Corporate Yard Few and minor amounts of significant materials are handled by Lathrop at the Corporate Yard. If oil changes are performed at the Corporate Yard, the waste motor oil is captured and stored in the hazardous waste area of the Well 7 site warehouse until it is disposed of properly.

•

Wells and Booster Stations The significant materials handled by Lathrop at the Wells, Booster Stations include sodium hypochlorite solution and diesel fuel. The diesel fuel at the Booster and larger Storm and Sewer Lift Stations are stored under the backup generators in 85500-gallon double walled tanks. The diesel fuel stored at well sites is stored in double walled tanks outside the well structures. Page 8

City of Lathrop Storm Water Pollution Prevention Plan Version 0

•

Storm Water and Sewer Lift Stations The significant materials handled by Lathrop at the larger Storm Water and Sewer Lift Stations are diesel fuel and food grade hydraulic fluid. The diesel fuel at the larger Storm and Sewer Lift Stations are stored under the backup generators in 85500 gallon doubled walled tanks. The food grade hydraulic fluid is used in the trash gates that are of a hydraulic fluid line design rather then a screw gate design.

Hydraulic fluid gate at the River Islands Storm Water Lift Station

Screw gate at Storm Water Lift Station M3

Contractors are utilized by Lathrop to perform all fueling activities for city owned backup generators. Lathrop has made contractual arrangements with the Lathrop-Manteca Fire District to fuel city vehicles and mobile equipment at the Lathrop-Manteca Fire District Fire East Station. On occasion Lathrop will fuel city vehicles or mobile equipment at a privately owned gas station. 5.3

Dust and Particulate Generating Activities

The permeable surface of the Well 7 site yard and Corporate Yard is covered by crushed rock to reduce dust and particulate generation due to vehicle and mobile equipment activities. The access road leading to Well 7 site is unpaved and dust generated by vehicle activity on the access road can settle in the permeable area that surrounds the Well 7 site. 5.4

Significant Spills and Leaks

Lathrop has had no spills of significant quantities on any of its properties since incorporating on July 1, 1989. 5.5

Non-Storm Water Discharges

Lathrop has made every effort to prevent all non-storm water sources from reaching the storm water system. Authorized non-storm water sources include atmospheric condensates (i.e. air conditioning units in the operations building); however, these sources generally do not produce enough volume to reach the storm water system. Lathrop does not allow unauthorized non-storm water sources including wash water from washing down city surfaces and equipment. City vehicles are not washed by O&M staff Page 9

City of Lathrop Storm Water Pollution Prevention Plan Version 0

or other Lathrop personnel. Lathrop has made arrangements with a local car wash business, so personnel with city vehicles are given vouchers to be used on an “as needed” basis. If a non-storm water discharge is observed, a Lathrop maintenance employee will investigate the source and make a determination of whether it is an authorized or an unauthorized non-storm water discharge. If the flow is found to be an illicit discharge, the maintenance employee will take corrective action necessary to terminate the illicit discharge and then report the illicit discharge and actions taken to his/her supervisor. 5.6

Soil Erosion

The areas of possible soil erosion are the permeable areas at the Corporate Yard and the Well 7 site. The permeable area at the Corporate Yard is stabilized by crushed rock and the permeable area at the Well 7 site is stabilized by native vegetation and crushed rock.

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6.0

Assessment of Potential Pollutant Sources

Lathrop, on an as-needed basis, reviews existing BMPs and/or operational changes that may affect the quality of its storm water discharges. A formal assessment is done at the end of each storm water year in conjunction with the ACSCE. This evaluation is described in detail in Section 8 of this plan. 6.1

Narrative Assessment

Pollutants that are most likely to be mobilized by storm water include petroleum hydrocarbons from periodic mobile equipment oil changes, equipment maintenance, and minor spills of diesel fuel or gasoline during equipment refueling. Other pollutants that may be mobilized by storm water include Roundup Pro and chlorine from leaks or spills. The likelihood of food grade hydraulic fluid as a pollutant is low due to regular maintenance of the storm water lift station hydraulic systems. 6.1.1

Likely Pollutants

Based on the above information and historical observations, the following is a list of potential pollutants most likely to be present in the Lathrop storm water discharges. The potential pollutants are listed in the order of their likelihood of being a pollutant present in the discharge:

6.2

1.

Petroleum hydrocarbons

2.

Roundup Pro

3.

Chlorine

4.

Food grade hydraulic fluid

5.

Raw sewage

Tabulated Overview of Likely Pollution Sources Area

Well 7 Site Corporate Yard Storm Water Lift Station Sewer Lift Station Wells Booster Stations

Indicator Dead vegetation, hydrocarbon (oil) sheen, odor Hydrocarbon (oil) sheen, odor Hydrocarbon (oil) sheen, odor Hydrocarbon (oil) sheen, odor Hydrocarbon (oil) sheen, odor Hydrocarbon (oil) sheen, odor, chlorine

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Suspect Pollutant Roundup Pro, Petroleum hydrocarbons Petroleum hydrocarbons Petroleum hydrocarbons, food grade hydraulic fluid Petroleum hydrocarbons, raw sewage Petroleum hydrocarbons, chlorine Petroleum hydrocarbons, chlorine

City of Lathrop Storm Water Pollution Prevention Plan Version 0

6.3

Operations Summary

Lathrop employees will develop and implement additional BMPs as appropriate and necessary to reduce or prevent pollutants associated with their specific area of responsibility or with a specific activity. Special construction or maintenance projects may require additional BMPs to prevent unauthorized discharges to the storm water conveyance system and to prevent contamination of storm water runoff. BMPs for each special project are considered on a case by case basis. Lathrop Public Works Department will coordinate such efforts with employees and outside contractors.

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7.0

Storm Water Best Management Practices (BMPs)

The General Permit states that, “BMPs are the activities, prohibition of practices, maintenance procedures, and other management practices used to prevent or reduce the pollution of storm water discharge. BMPs also include treatment measures, operating procedures, and practices to control site runoff, spillage, leaks, sludge or waste disposal, or drainage from raw material storage.” BMPs may include any type of pollution prevention and pollution control measure necessary to achieve compliance with the General Permit. The following describes the non-structural (preventative practices) and structural (preventative structures) BMPs utilized at Lathrop. 7.1

Non-Structural BMPs

The following are prevention practices utilized by Lathrop to minimize the possibility of pollution of storm water discharge. 7.1.1

Good Housekeeping

Lathrop has established standard operating procedures that address good housekeeping, for O&M Division personnel. These procedures prevent pollutants such as solids or oil and grease from moving offsite by track out or wind. They also minimize the likelihood of a release to the environment. 7.1.1.1 Wells 6, 8, 9, and 21 Good Housekeeping BMPs for Wells 6, 8, 9, and 21 include: • • • • • • •

Use of dry clean methods whenever practicable Backup generator is kept under cover After backup generator maintenance, clean area of drips, spills, leaks and debris at the completion of a task or before the end of a work shift Worker(s) performing backup generator maintenance have a spill kit readily available Diesel Fuel contractors use drip pans during fueling activities Diesel Fuel contractors have spill kits readily available for use When practicable; restocking of chlorine units, outside a covered structure, will not be performed during storm events

7.1.1.2 Well 7 Site Well 7 utilize the same BMPs as the other wells; however, Good Housekeeping BMPs for the Well 7 Site (warehouse, storage containers, yard, and adjoining trash bin area, north of the north perimeter) include: • • • •

Trash bins are closed and locked when not in use Chemicals stored under cover Worker(s) performing equipment maintenance have a spill kit readily available Equipment maintenance is performed inside or under cover whenever possible Page 13

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• • • • • • • •

Sweep warehouse, clean spills and leaks to avoid track out Oily parts are stored inside warehouse or storage containers Cover larger oily parts stored in the yard Asphalt pile is well maintained and is covered when not in use Parked vehicles and mobile equipment are checked periodically for drips or leaks; drip pans and/or oil absorbent pads are used when necessary Drip pans or tarps used while performing mobile equipment oil changes Hazardous waste is stored inside the warehouse on containment pallets until disposed of properly. Used motor oil is stored in a designated, labeled 42-gallon drum, inside the warehouse, until disposed of properly

7.1.1.3 Water Tanks and Booster Stations Good Housekeeping BMPs for the Water Tanks and Booster Stations include: • • • • • •

Use of dry clean methods whenever practicable After backup generator maintenance, clean area of drips, spills, leaks and debris at the completion of a task or before the end of a work shift Worker(s) performing backup generator maintenance have a spill kit readily available Diesel Fuel contractors use drip pans during fueling activities Diesel Fuel contractors have spill kits readily available for use Water treatment chemicals are stored under cover; inside Booster Station structure

7.1.1.4 Storm Water Lift Stations Good Housekeeping BMPs for Storm Water Lift Stations include: • • • • • • • • •

Use of dry clean methods whenever practicable After backup generator maintenance, clean area of drips, spills, leaks and debris at the completion of a task or before the end of a work shift Worker(s) performing backup generator maintenance have a spill kit readily available Diesel Fuel contractors use drip pans during fueling activities Diesel Fuel contractors have spill kits readily available for use Several Storm Water Lift Stations installed with a non-polluting screw type trash gate system rather than hydraulic fluid system Perform trash gate food grade hydraulic system maintenance during dry season Capture food grade hydraulic fluid leaks and drips during trash gate hydraulic system maintenance Clean food grade hydraulic fluid leaks and drips upon completion of trash gate hydraulic system maintenance

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7.1.1.5 Corporate Yard Good Housekeeping BMPs for Corporate Yard include: • • • • • • •

Use of dry clean methods whenever practicable Trash bins are closed and locked when not in use Chemicals stored under cover Parked vehicles and mobile equipment are checked periodically for drips or leaks; drip pans and/or oil absorbent pads are used when necessary Drip pans or tarps used while performing mobile equipment oil changes Hazardous waste is stored at the Well 7 Site inside the warehouse on secondary containment pallets until disposed of properly, Used motor oil is stored in a designated labeled 42-gallon drum inside the warehouse until disposed of properly

7.1.1.6 Sewer Lift Stations Good Housekeeping BMPs for Sewer Lift Stations include: • • • • •

Use of dry clean methods whenever practicable After backup generator maintenance, clean area of drips, spills, leaks and debris at the completion of a task or before the end of a work shift Worker(s) performing backup generator maintenance have a spill kit readily available Diesel Fuel contractors use drip pans during fueling activities Diesel Fuel contractors have spill kits readily available for use

7.1.2

Preventative Maintenance

The Lathrop preventative maintenance program is designed to maintain the facility and equipment in good operating condition, which reduces the potential for pollutants to enter the storm water conveyance system. The following visual inspections are performed on a monthly basis: •

Proper pump operation, electrical connections and grounding, backup generator fuel tank exterior (visually observe for corrosion or leaks).

7.1.3

Spill Prevention and Response

In an effort to minimize pollutants from coming into contact with storm water, Lathrop has absorbent materials, booms and spills kits readily available wherever there are liquid hazardous materials of significant quantities stored. Lathrop is not required under the Code of Federal Regulations, Title 40, subpart A, section 112.1, to have a Spill Prevention, Control, and Countermeasure Plan (SPCC Plan).

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7.1.4

Material Handling and Storage

The handling of the significant materials is conducted in six areas of Lathrop: Well 7 Site, Corporate Yard, Wells, Booster Stations, Storm Water, and Sewer Lift Stations. The volumes of the significant materials are indicated in Section 4.0. Lathrop O&M Division employees and contractors are expected to follow all of Lathrop’s BMPs during fueling and equipment maintenance activities. 7.1.4.1 Municipal Water Line Flushing/Potable Water Source Discharges Lathrop has two main sources of authorized non-storm water discharges: fire hydrant purging and testing and well and AST purging and testing. Fire hydrant purging and testing is performed by the Lathrop-Manteca Fire Department at various locations throughout the city. The fire hydrant purging and testing, in most cases is discharged to the Lathrop municipal storm drain system and the discharged effluent does not come into contact with any significant materials handled by Lathrop. AST and well purging and testing, discharges potable water to a designated retention basin where the effluent percolates into the permeable surface and/or evaporates. The purged effluent does not come into contact with any significant materials handled by Lathrop.

Pete Freire AST Detention Basin

7.1.5

Well 7 Detention Basin

Employee Training

All Lathrop employees receive training in good housekeeping practices and on the job training in a number of areas pertaining to their specific positions. Lathrop management periodically conducts safety meetings covering topics pertaining to safety, good housekeeping practices and overall facility operations. 7.1.6

Waste Handling/Recycling

Lathrop personnel and contractors follow Lathrop policy and procedures for hazardous waste accumulation areas, waste handling, waste characterization, container management, labeling procedures, recycling, documentation, and other related topics. Proper waste management and waste minimization reduces or prevents the following pollutants from

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coming into contact with storm water: Oil & grease, used absorbents, oily debris, and hazardous wastes from spill clean up. Hazardous waste at Lathrop is primarily generated by mobile equipment maintenance. Mobile equipment maintenance, with the exception of periodic oil changes, is performed offsite by outside contractors. The limited amount of hazardous waste generated by Lathrop’s industrial activities is stored in secondary containment in the warehouse at the Well 7 site. Accumulated hazardous waste is disposed of by a contractor. Lathrop management or a management designee is responsible for daily and weekly inspections of all hazardous waste generated and stored at Lathrop. Conditions may warrant additional inspections as deemed necessary by Lathrop management. 7.1.7

Record Keeping and Internal Reporting

Lathrop maintains records of all facility diagrams, SWPPP plan updates, and any other information at the O&M Division administration building. All records are maintained for a period of no less than five years. Storm water issues that are documented include: housekeeping issues, necessary maintenance, follow-up action for spills, necessary BMP modifications and similar issues. 7.1.8

Erosion Control and Site Stabilization

Permanent BMPs used at Lathrop properties to control sediment and prevent soil erosion include covering soil surfaces with asphalt, concrete, crushed rock, and vegetation. If any evidence of erosion or areas needing repair is observed, the areas needing attention will be called to the attention of the Lathrop area supervisor. Required repairs are made promptly. Asphalt, concrete, crushed rock, shovels, and hand tools are used to implement site stabilization and erosion control. 7.1.9

Inspections

This section describes the inspections pertaining to storm water compliance issues. (Preventative maintenance inspections are discussed in Section 7.1.2.). Daily Visual Inspections: Lathrop O&M Division supervisor or designees perform daily visual inspections of their work areas, looking for anything that might impact storm water. Monthly General Facility Inspection: Lathrop O&M Division supervisor or designees perform monthly visual inspections of Lathrop facilities, equipment and mobile equipment, looking for anything that might impact storm water. Wet Season Periodic Trash Gate and Vortex Separator Inspection: During the wet season, the O&M Division supervisor or designees performs periodic inspections of the Storm Water Lift Station trash gates and Vortex separators. Maintenance is performed if necessary. Page 17

City of Lathrop Storm Water Pollution Prevention Plan Version 0

Annual Comprehensive Site Compliance Evaluation (ACSCE): Lathrop O&M Division supervisor or designees perform and document an ACSCE modeled after the Industrial General Permit during the month of May. The inspection consists of visual inspections of storm drain, potential outfalls, drainage areas, and activities at the differing Lathrop facilities. If needed, updates to the SWPPP will be made in a timely manner. 7.1.10 Quality Assurance To ensure implementation of the Storm Water Pollution Prevention Plan, Lathrop has developed and currently uses the following “Quality Assurance/Quality Control (QA/QC)” BMPs. One QA/QC BMP is the ACSCE. This ACSCE is described in detail in Section 8 of this plan. The ACSCE provides a specific opportunity to evaluate the effectiveness of the SWPPP and current BMPs, and to determine whether or not additional BMPs should be utilized. The periodic meetings of the Pollution Prevention Team (described in Section 2.1 of this plan) are another QA/QC BMP. The meeting of staff members responsible for the various areas and components of the SWPPP provides a format for accountability in implementing and evaluating the BMPs. 7.2

Structural BMPs

Structural BMPs consist of structural devices that prevent, reduce and/or treat pollutants in storm water discharges and non-storm water discharges. The following describes some of the structural BMPs utilized at Lathrop 7.2.1

Overhead Coverage

The backup generators and pumps located at the Wells are housed inside a structure which minimizes their exposure to storm water. All chemicals listed in Section 4 are stored in the Well 7 Site warehouse and/or storage containers, the Corporate Yard storage structure, Booster Station structures or under the partial roof of the Storm Water Lifts Stations M1-M6. 7.2.2

Retention Basins

Partial Roof at Storm Water Lift Station M3

Lathrop ASTs and wells have retention basins for the purpose of containing potable water purging, and testing discharges. The retention basins have a permeable surface so the discharged effluent percolates and/or evaporates. The potable water effluent does not comingle with storm water or enter the Lathrop municipal storm drain system.

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City of Lathrop Storm Water Pollution Prevention Plan Version 0

7.2.3

Control Devices

Lathrop maintains the public municipal storm drain system that ultimately routes storm water off streets and away from structures to the San Joaquin River. The backup generators diesel fuel tanks are doubled walled to prevent leaks due to damage or corrosion. 7.2.4

Secondary Containment Structures

Lathrop utilizes secondary containment pallets for the storage of fuel and hazardous waste at the Well 7 site. 7.2.5

Treatment

There are two structural BMP items at the larger Storm Water Lift Stations to treat storm water before it being discharged to the San Joaquin River: trash gates and Vortex Separators. As storm water influent flows to a Storm Water Lift Station, it is channeled through a trash gate where lager debris from the storm water is retrieved and disposed of properly. The storm water is then channeled to a concrete vault where it is sump pumped through a Vortex Separator. The Vortex Separator uses centripetal forces to capture settable solids, floating debris, and oils not captured by the trash rake. The Well 7 Site utilize native vegetation which acts as a bio-filter to remove solids and other pollutants from storm water and crushed rock which aids in controlling erosion and settling out solids.

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City of Lathrop Storm Water Pollution Prevention Plan Version 0

7.3

Tabulated Descriptions

The following table summarizes the activities at Lathrop, the potential pollutant sources and the potential pollutants. BMPs for the potential pollutant sources are also listed. Area

Activities

Pollutant Sources

Wells 6, 8, 9, and 21

• Pumping groundwater to ASTs • Periodic well treatment

• Diesel fuel tank • Backup generator maintenance • Water Treatment drum

Well 7 Site

• Pumping groundwater to ASTs • Periodic well treatment • Equipment, hazardous and hazardous waste materials storage

• Diesel fuel tank • Backup generator maintenance • Equipment maintenance • Mobile equipment oil changes • Hazardous materials, hazardous waste storage areas

Potential Pollutants • Petroleum hydrocarbons • Chlorine • Suspended solids

• Petroleum hydrocarbons • Roundup Pro • Various solvents and detergents

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Best Management Practices • Backup generator is kept under cover • After backup generator maintenance, clean area of drips, spills, leaks, and debris at the completion of a task or before the end of a work shift • Worker(s) performing backup generator maintenance have a spill kit readily available • Diesel Fuel contractors use drip pans during fueling activities • Diesel Fuel contractors have spill kits readily available for use • When practicable; restocking of chlorine units, outside a covered structure, will not be performed during storm events • Native vegetation used for erosion control • Double walled diesel fuel tank • Trash bins are closed and locked when not in use • Chemicals stored under cover • Worker(s) performing equipment maintenance have a spill kit readily available • Equipment maintenance is performed inside or under cover whenever possible • Warehouse is swept and spills and leaks cleaned to avoid track out • Oily parts are stored inside warehouse or storage containers

City of Lathrop Storm Water Pollution Prevention Plan Version 0

Area

Activities

Pollutant Sources

Well 7 Site (Cont.)

• Minor equipment and mobile equipment maintenance • Vehicle and mobile equipment parking

• Parked vehicles and mobile equipment

Water Tanks and Booster Stations

• Potable water treatment, storage and distribution

• Diesel fuel tank • Backup generator maintenance • Water Treatment

Potential Pollutants

• Petroleum hydrocarbons • Chlorine

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Best Management Practices • Larger oily parts stored in the Yard are covered • Asphalt pile is well maintained and is covered when not in use • Parked vehicles and mobile equipment are checked periodically for drips or leaks; drip pans and/or oil absorbent pads are used when necessary • Drip pans or tarps used while performing mobile equipment oil changes • Hazardous waste is stored inside the warehouse on containment pallets until disposed of properly • Used motor oil is stored in a designated 42 gallon drum, inside the warehouse, until disposed of properly • Absorbent materials, booms and spill kits • Crushed rock and native vegetation is used for minor storm water treatment and erosion control • Double walled diesel fuel tank • After backup generator maintenance, clean area of drips, spills, leaks and debris at the completion of a task or before the end of a work shift • Worker(s) performing backup generator maintenance have a spill kit readily available • Diesel Fuel contractors use drip pans during fueling activities • Diesel Fuel contractors have spill kits readily available for use • Water treatment chemicals are stored under cover; inside Booster Station structure

City of Lathrop Storm Water Pollution Prevention Plan Version 0

Area

Water Tanks and Booster Stations (Cont.) Storm Water Lift Stations

Activities

Pollutant Sources

Potential Pollutants

Best Management Practices • Site paved for erosion control • Double walled diesel fuel tank

• Storm water conveyance and treatment

• Diesel fuel tank • Backup generator maintenance • Hydraulic powered trash gate

• Petroleum hydrocarbons • Food grade hydraulic fluid

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• After backup generator maintenance, clean area of drips, spills, leaks and debris at the completion of a task or before the end of a work shift • Worker(s) performing backup generator maintenance have a spill kit readily available • Diesel Fuel contractors use drip pans during fueling activities • Diesel Fuel contractors have spill kits readily available for use • Storm Water Lift Stations use a non-polluting screw type trash gate system rather than hydraulic fluid system • Perform trash gate hydraulic system maintenance during dry season • Capture food grade hydraulic fluid leaks and drips during trash gate hydraulic system maintenance • Clean food grade hydraulic fluid leaks and drips upon completion of trash gate hydraulic system maintenance • Double walled diesel fuel tank • Trash gates • Vortex separators

City of Lathrop Storm Water Pollution Prevention Plan Version 0

Area

Activities

Pollutant Sources

Corporate Yard

• O&M administration • Equipment and hazardous materials storage • Minor mobile equipment maintenance • Vehicle and mobile equipment parking

• Mobile equipment oil changes • Hazardous materials storage • Parked vehicles and mobile equipment

Sewer Lift Stations

• Sewage conveyance

• Diesel fuel tank • Backup generator maintenance • Sewer backup

Potential Pollutants • Petroleum hydrocarbons • Various solvents and detergents

• Petroleum hydrocarbons • Raw sewage

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Best Management Practices • Trash bin are closed and locked when not in use • Chemicals stored under cover • Parked vehicles and mobile equipment are checked periodically for drips or leaks; drip pans and/or oil absorbent pads are used when necessary • Drip pans or tarps are used while performing mobile equipment oil changes • Until disposed of properly, hazardous waste is stored at the Well 7 Site inside the warehouse, on secondary containment pallets • Used motor oil is stored in a designated 42 gallon drum, inside the warehouse, until disposed of properly • Absorbent materials, booms and spill kits • Records maintained for no less then 5 years • Paving and crushed rock used for erosion control • After backup generator maintenance, clean area of drips, spills, leaks and debris at the completion of a task or before the end of a work shift • Worker(s) performing backup generator maintenance have a spill kit readily available • Diesel Fuel contractors use drip pans during fueling activities • Diesel Fuel contractors have spill kits readily available for use • Double walled diesel fuel tank

City of Lathrop Storm Water Pollution Prevention Plan Version 0

Area

Activities

Pollutant Sources

Potential Pollutants

Best Management Practices • Use of dry clean methods whenever practicable • Monthly and ACSCE Inspections • Annual storm water training

All Industrial Areas

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8.0

Annual Comprehensive Site Compliance Evaluation (ACSCE)

Once a year, a storm water annual comprehensive site compliance evaluation (ACSCE) is performed at Lathrop. This comprehensive evaluation consists of the following items. 8.1

Visual Inspection of Potential Pollutant Sources Site Drainage

During the ACSCE, a facilities inspection is performed. Every facility storm water outfall is inspected for non-storm water discharges and for signs of contaminated discharges, such as, abnormal vegetation requiring maintenance. Facility activities occurring in storm water drainage zones are inspected for potential pollutant sources. The inspection also consists of an evaluation of the existing BMPs and the need for additional BMPs. A record of the inspection findings is stored at the Lathrop O&M Division Administration Building. 8.2

Review and Evaluation of the BMPs

During the facility inspection, the existing BMPs are inspected to ensure they are being implemented properly. The BMPs are evaluated for effectiveness based on the field inspection and discharge observations. If additional BMPs need to be utilized as a result of the ACSCE, the SWPPP is updated and BMPs implemented accordingly. 8.3

ACSCE Inspector

The ACSCE may be performed by Lathrop O&M Division management, staff and/or an environmental contractor.

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City of Lathrop Storm Water Pollution Prevention Plan Version 0

9.0

SWPPP Changes

The SWPPP will be revised, as appropriate, and implemented prior to changes in industrial activities that: (1) May significantly increase the quantities of pollutants in storm water discharge (2) Cause a new area of industrial activity at the facility to be exposed to storm water (3) Begin an industrial activity that would introduce a new pollutant source at the facility The SWPPP will be revised in a timely manner.

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FIGURE 1 VICINITY MAP

Figure 1 City of Lathrop Vicinity Map

FIGURE 2 TOPOGRAPHIC DRAINAGE MAP

Figure 2 City of Lathrop Topographical Drainage Map

North Lathrop

Outfall 4

Lathrop Industrial

Central Lathrop Historic Lathrop

Outfall 2

Outfall 3

Outfall 1 Mossdale

River Islands

Crossroads Business Park

South Lathrop

Map Legend — Outfalls Outfall 1 — Crossroads Outfall Outfall 2 — Mossdale Outfall Outfall 3 — East Lathrop Outfall Outfall 4 — Dos Reis Outfall

FIGURE 3 PUBLIC WORKS DEPARTMENT & PARK MAINTENANCE ORGANIZATIONAL CHART

Figure 3 Public Works Department & Park Maintenance Organizational Chart

Operations & Maintenance Supervisor

Prepared by:

WGR Southwest, Inc. 315 W. Pine Street, Suite 8 Lodi, CA 95240 (209) 334-5363 www.wgr-sw.com