Lydia Frenzel Conference Series - Advisory Council

Thank you for downloading this file. If you would like further information on water jetting visit the Lydia Frenzel Conference Series. The Advisory Council is a nonprofit, privately funded membership organization that provides a forum for dialogue and the dissemination of information pertaining to the economic and social effects of technological development throughout the world.

The Council solicits and makes available pertinent information from both private and public sources, seeks expression of points of view from all who may wish to contribute, advances consensus opinions and selected issues of standards and standards organizations, develops networking to match speaking and information resources with the needs and demands of the community, and promotes specific seminars and symposia.

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This mission is viewed as important because the conservation of resources, particularly the public infrastructure, has a significant and long lasting economic impact on the well-being of every citizen.

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Managing Shipyard Stormwater Discharges

Alternatives for Control, Collection, and Treatment of Shipyard Stormwater

Barry L. Kellems1, P.E, Fabian F. Sanchez2, Lynwood P. Haumschilt3 Presented at the 11th Annual Southern States Environmental Conference

Shipyard Environmental Issues Track Gulfport, Mississippi

September 2001

Abstract Shipyards are facing increased regulation of stormwater discharges through the National Pollutant Discharge Elimination System (NPDES) permitting process. While traditional Best Management Practices (BMPs) can significantly reduce the contaminantion of stormwater, BMPs alone will not be sufficient to comply with impending regulatory limits. The development of low-cost but effective stormwater control, collection, and treatment alternatives is necessary to minimize environmental compliance costs at U.S. shipyards and strengthen the public image of shipyards as stewards of the environment. This paper presents an assessment of alternatives for managing shipyard stormwater and preliminary results for an innovative technology currently undergoing testing.

1Senior Associate, Hart Crowser, Inc., 1910 Fairview Avenue East, Seattle, Washington 98102. 2Engineer, Hart Crowser, Inc. 3Consultant, LPH Consulting, 17546 Caminito Balata, San Diego, California 92128.

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Introduction The first lines of defense for keeping pollutants out of receiving waters are source control and BMPs. It is always more cost-effective to implement source control and BMPs to prevent pollution rather than collect and treat stormwater to remove pollutants after the fact. Alternatives to direct surface water discharge of shipyard stormwater include infiltration, diversion to the municipal sewer, and treatment prior to surface water discharge. Each of these alternatives has advantages and disadvantages. In the past the standard approach for treating shipyard stormwater was by using physical-chemical methods. Recently, pilot-scale testing of organic-based filtration has proven to be a more economical treatment alternative. Full-scale testing of an organic-based filtration process is ongoing at the NASSCO shipyard in San Diego.

Characterization of Shipyard Stormwater Shipyard stormwater can be characterized as containing relatively high concentrations of metals, intermediate concentrations of solids, and low concentrations of Oil and Grease. Typical stormwater influent characteristics and discharge requirements for shipyards located in the Puget Sound region of Washington State and a shipbuilding facility in San Diego, California, are presented in Table 1. The Puget Sound influent concentrations are the average for six representative shipyards. Effluent requirements from Water Quality Standards for Surface Waters of The State of Washington (Chapter 173-201A WAC) are based on chronic toxicity. The San Diego shipyard influent concentrations are the average for drainage SW-3 at the NASSCO shipyard. Effluent requirements were calculated using the influent concentrations and toxicity discharge requirements for surface water discharge in CA RWQCB San Diego Region Order 97-36. The Oil and Grease limitation is based on a 30-day average. Typically, copper and zinc are the controlling parameters for managing shipyard stormwater. Table 1. Shipyard Stormwater Influent Characteristics and Discharge Requirements

Puget Sound Shipyard San Diego Shipyard Parameter Influent Effluent Influent Effluent

Copper in ug/L 220 3.1 340 37 Lead in ug/L 59 8.1 90 NR Zinc in ug/L 860 81 1,400 300 TSS in mg/L 40 NR 26 NR Oil and Grease in mg/L 4 NR 8 25 NR = Not explicitly regulated

Control, Collection, and Treatment Technologies

Approaches

Current technologies available for managing shipyard stormwater discharges in the U.S. have either been expensive or have not proven to be effective in reducing metals concentrations to acceptable regulatory limits. Puget Sound shipyards have established BMPs, which entail the

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application of operational improvements and source control technologies to prevent stormwater runoff from contacting blasting grit, paint chips, oils, and other potentially contaminating material. Examples of stormwater BMPs include containment of spent grit, routine sweeping of paved areas, scheduled cleaning of sumps and drain lines, and proper storage and handling of hazardous materials (PPRC 1997). Other control technologies such as stormwater infiltration, discharge to sanitary sewer, and treatment prior to surface water discharge are site-specific and must be evaluated on a case-by-case basis prior to being implemented.

Stormwater Treatment Technologies A screening of potentially applicable technologies for treatment of stormwater discharges is presented in Table 2. These technologies were identified and screened based on potential effectiveness and technical feasibility. A cost-effective and implementable technology to control shipyard stormwater discharges is needed as the application of current treatment options (e.g., chemical precipitation and sedimentation) are impractical due to the large volumes of stormwater as well as the relatively low but variable dissolved metal concentrations in stormwater. The results of the screening survey indicated that organic-based enhanced filtration would be a viable alternative to remove metals from shipyard stormwater. Pilot Testing of Enhanced Filtration In 1997, Hart Crowser was hired by a group of shipyards in the Puget Sound region to conduct a bench-scale treatability study of enhanced filtration of stormwater. During this study, stormwater from two active shipyards was tested with three organic-based filtration media produced from leaf compost, peat, and other humic substances. The three filter media tested included: CSF Humic Filter Media, Multisorb 100, and ATA aqua-Fix. These media were selected based on their effectiveness in removing constituents of concern (COCs) in shipyard stormwater (e.g., copper, zinc, lead, and total suspended solids) and their feasibility to be implemented on a full-scale enhanced filtration testing project. Media that cannot be implemented because of lack of commercial availability or technical constraints at a typical shipyard were eliminated. A summary of the bench-scale test criteria and results for the CSF media is presented in Table 3. A treatability test was performed in multiple columns containing the selected filtration media to assess their performance during actual simulated shipyard hydraulic conditions. A layout of the test apparatus is shown on Figure 1. A short-term test using actual shipyard stormwater and a coarse media (screen size 0.11 to 0.06 inch) was performed to determine removal efficiencies and attainable discharge concentrations of the stormwater COCs. In a similar fashion, a long-term test designed to measure removal efficiencies of the dissolved metals was also performed using synthetic stormwater without solids to minimize plugging, and a finer media (screen size 0.055 to 0.023 inch). The findings of the bench-scale study revealed that the media were able to remove up to 97 and 94 percent of the dissolved copper and zinc, respectively, but that actual performance would be strongly dependent on solids loading. Based on these results, an economic cost analysis demonstrated that enhanced filtration was a cost-effective alternative for treatment

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Table 2. Identification and Screening of Potentially Applicable Technologies (Hart Crowser 1997) Technology Description Effectiveness Technical Feasibility Screening Results Catch Basin Inserts Provide inlet protection using

commercially available fabric or insert type

Low: Does not capture dissolved pollutants or fine particulates

Medium: Has excessive operational requirements

Eliminated

Swirl Regulators and Concentrators

Catch basins or treatment units with inside structure designed to improve solids and oil removal and retention


Medium: Requires purchase of new catch basin and/or treatment system for concentrated solids

Eliminated

Detention Pond Lowers runoff velocities and allows settling of particulate pollutants


Low: Depends on land availability. Typical shipyard has low land availability

Eliminated

Biotreatment Bioswales or grass filter strips lower runoff velocity and acts as a filter to trap particulate pollutants

Medium: Limited effectiveness for dissolved pollutants

Low: Depends on land availability. Typical shipyard has low land availability

Eliminated

Sand Filtration Filter stormwater through sand filter, trapping particulate pollutants

Medium: Limited effectiveness for dissolved pollutants

Medium: Requires redesign of storm sewer lines and purchase of filtration unit

Retained for detailed analysis as baseline treatment method

Enhanced Filtration Filter stormwater through enhanced filtration media, trapping particulate pollutants. Dissolved metal removal may be possible

Uncertain: Performance data limited

Medium: Requires redesign of storm sewer lines and purchase of filtration unit

Retained for bench-scale testing followed by detailed analysis

Chemical Precipitation and Sedimentation

Design system to optimize reduction in pollutant concentrations. System may include ultrafiltration or ion exchange unit for dissolved metal removal

High: System designed to achieve optimal removal of pollutants

Medium: Requires purchase of storage tanks and treatment system

Retained for detailed analysis as baseline treatment method

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Table 3. Summary of 1997 Bench-Scale Test Criteria and Results (Hart Crowser 2000) Unrestricted Flow Controlled Flow Removal Rate in Percent

Test Media Sieve

Size Screen Size in

Inches Flow Rate in

gpm/SF Flow Rate in

gpm/CF Average Flow

Rate in gpm/SF Average Flow

Rate in gpm/CF Copper Lead Zinc TSS Short-Term High Loading* #7 to #13 0.11 to 0.06 17 9 3.3 1.7 50 28 83 44 Short-Term Low Loading* #7 to #13 0.11 to 0.06 13 7 2.4 1.2 49 23 85 38 Long-Term 500 EBV** #14 to #30 0.055 to 0.023 14 14 2 2 97 82 94 NM Long-Term 900 EBV** #14 to #30 0.055 to 0.023 14 14 2 2 97 95 71 NM

* Short-term results based on treatment of Marco Shipyard (Seattle) stormwater, average of three effluent samples. ** Long-term results based on treatment of synthetic stormwater containing no suspended solid. Grab samples collected following treatment of 500 and 900 empty bed volumes (EBV).

NM = Not Measured

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Figure 1. Test Column Schematic

of shipyard stormwater. As an illustration, the cost-effectiveness of copper removal is shown on Figure 2. Based on the Clean Water Act, the most cost-effective option would be located at the “Knee” of the curve, in this case end of pipe enhanced filtration. Upon completing the pilot testing, the main data gap from this study involved the long-term performance of the system under dynamic hydraulic and chemical loadings. The demonstration project currently underway at the NASSCO shipyard will address this data gap and document the performance of enhanced filtration in a full-scale, long-term shipyard application. Full-Scale Testing of Enhanced Filtration With the sponsorship of the National Steel Research Program (NSRP), full-scale testing of enhanced filtration is currently ongoing at the NASSCO shipyard in San Diego. This facility is the largest new construction shipyard on the West Coast. In partnership with NASSCO, Hart Crowser was responsible for evaluation and selection of the process options for testing, and final design of the filtration test units. Stormwater Management, Inc. (Portland, Oregon) also assisted in the project by providing equipment and installation support. The NASSCO demonstration project will complete the testing cycle of enhanced filtration and provide a comparative performance analysis of three filtration media options in a shipyard setting, as well as cost data for the industry.

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Figure 2. Cost-Effectiveness of Copper Removal The project consists of the installation of a stormwater filtration system that treats 95 percent of the runoff from approximately 10 acres of the shipyard. System design and construction were completed in 2000 and 2001, respectively. Stormwater from drainage areas SW-3 is split using a flow splitter manhole and treated through a filtration system consisting of three different treatment trains. A flow schematic of the filtration system is shown on Figure 3. The filtration system will be an off-line facility located at the downstream end of the existing SW-3 outfall. The treatment trains consist of concrete vaults containing cartridge filters filled with various grain sizes of leaf compost (CSF) filtration media. A schematic of the patented stormwater management filter cartridge unit is presented on Figure 4. Treated effluent from the treatment vaults will pass through a simple sampling vault and then into an effluent pump station manhole, where stormwater will be pumped back to the existing outfall for discharge to San Diego Bay. To assess the effectiveness of various treatment configurations, three separate parallel treatment trains were installed. Overall, the goal of the filtration system was to test three grain size distributions of compost media for the removal of solids and metals from stormwater runoff. The operational phase of the project will be performed during storm events and will involve continuous monitoring of the filtration media for both hydraulic performance and chemical removal capacity. Initial testing has just begun, and data are still being analyzed.

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Figure 3. Filtration System Schematic

Figure 4. Self-Cleaning Filter Cartridge

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A comparative analysis of the stormwater monitoring data collected during testing of the three alternative treatment trains will be conducted. Based on this analysis, a preferred treatment scheme will be selected or design modifications to the existing schemes will be made. Also, the feasibility and practicability of full-scale stormwater filtration at the NASSCO shipyard will be assessed. Although full-scale testing of organic-based enhanced filtration is still underway, the effectiveness and technical feasibility of this technology in controlling shipyard stormwater discharges is promising based on the results of the bench-scale treatability study. Summary and Conclusions Because BMPs alone have not been successful in reducing concentration of COCs in shipyard stormwater to regulatory limits, a cost-effective technology to control and manage shipyard runoff is needed. Among the feasible alternatives, filtration is of interest because filters are effective during intermittent flows, and because they can be readily implemented in below-ground, gravity-flow configurations, thus minimizing the space requirement posed by building a large chemical treatment plant. In addition, the higher metal removal capacity of an organic-based filtration media produced from leaf compost have made this technology attractive to the shipyard industry. Testing performed to date has been limited to lab-scale only. Even though this technology appears cost-effective and technically feasible, actual performance and costs of enhanced filtration have not yet been established for shipyards and these will impact the actual feasibility of this treatment alternative. For that purpose, a full-scale demonstration project to provide actual cost and performance guidelines for the industry is currently ongoing at the NASSCO shipyard in San Diego. Only after the completion of this project can definite assessment of the full-scale applicability of this technology to treat shipyard stormwater be performed.

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References Hart Crowser 1997. Shipyard AKART Analysis for Treatment of Storm Water, Final Report prepared for Maritime Environmental Coalition, May 7, 1997. Hart Crowser 2000. Demonstration of Enhanced Filtration for Treatment of Shipyard Stormwater San Diego, California. Design Report prepared for National Shipbuilding Research Program, July 2000. Pacific Northwest Pollution Prevention Resource Center (PPRC) 1997. Pollution Prevention at Shipyards, Seattle, Washington, September 1997.

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11/18/2001Southern States Environmental Conference 2001 Shipyard Track 1

Managing Shipyard Stormwater DischargesAlternatives for Control, Collection, and Treatment of Shipyard Stormwater

Barry KellemsHart Crowser, Inc. Delivering smarter solutions

11/18/2001Southern States Environmental Conference -Shipyard Track 2

Increased Regulation

• Increasingly Stringent Discharge Limitations under NPDES

• Copper and Zinc Typically Control

• Toxicity Standards Becoming More Prevalent

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Puget Sound Shipyard San Diego Shipyard Param eter Influent(1) Effluent

(2) Influent(3) Effluent (4)

Copper 220 ug/L 3.1 ug/L 340 ug/L 37 ug/L

Lead 59 ug/L 8.1 ug/L 90 ug/L NR Zinc 860 ug/L 81 ug/L 1,400 ug/L 300 ug/L TSS 40 m g/L NR 26 m g/L NR Oil and Grease 4 m g/L NR 8 m g/L 25 m g/L

(1) Influent concentrations are the average for six representative shipyards located in the Puget Sound region of W ashington State. (2) Effluent requirem ents from “W ater Quality Standards For Surface W aters Of The State Of W ashington (Chapter 173-201A W AC) and are based on chronic toxicity. (3) Influent concentrations are the average for drainage SW -3 at the NASSCO shipyard in San Diego, California. (4) Effluent requirem ents calculated using the influent concentrations (3) and toxicity discharge requirem ents in CA RW QCB San Diego Region Order 97-36. Oil and Grease lim itation based on a 30-day average. NR = Not explicitly regulated.

Shipyard Stormwater Influent Characteristics AndDischarge Requirements


Current Technologies Limited

• Current Technology - Limited Effectiveness or Expensive

• Source Control and/or BMPs Typically Cannot Reach Limits

• A Cost-Effective Technology is Needed to Control Shipyard Stormwater.

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Control Technologies

• Source Control

- Planning, material substitution

• Best Management Practices

- Segregation, sweeping, maintenance

• Stormwater Infiltration or Sewer Discharge

• Stormwater Treatment Prior to Surface Water Discharge


Stormwater Treatment Alternatives• Evaluation Conducted for Puget Sound

Shipyards in 1997

• Screening of Technologies Based on Effectiveness and Technical Feasibility Indicated that Enhanced Filtration (Organic-Based) Would be Viable

• Screening of Filtration Media Indicated that CSF Humic (Leaf Compost) Filter Media and Others Warranted Testing

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Treatability Test of Filter Media

• Column Testing to Assess Performance of Various Filter Media

• Two Real Stormwaters and One Synthetic Stormwater Tested

• Average Coarse Media Zinc Removal of 80%

• Average Coarse Media Copper Removal of 50%

• Fine Media Removals up to 100%

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Total Copper, Total Zinc, And TSS Results for Fine Compost Column Test

Run Avg. TSS Conc. (mg / L) Avg. Total Cu Conc. (mg / L) Avg Total Zn Conc. (mg / L)Influent Effluent Removal Influent Effluent Removal Influent Effluent Removal

1 25.5 1.0 96% 0.555 0.095 83% 2.800 0.190 93%2 15.5 1.5 90% 0.335 0.060 82% 1.600 0.076 95%3 19.0 0.0 100% 0.135 0.026 81% 0.715 0.043 94%4 52.5 3.6 93% 0.605 0.096 84% 4.250 0.125 97%5 14.5 0.0 100% 0.345 0.068 80% 1.800 0.099 95%6 17.5 1.0 94% 0.340 0.068 80% 1.650 0.097 94%7 4.0 0.0 100% 0.075 0.025 67% 0.180 0.029 84%8 23.5 1.0 96% 0.575 0.074 87% 3.000 0.092 97%9 25.0 1.5 94% 0.420 0.061 86% 1.600 0.054 97%10 21.5 1.0 95% 0.390 0.057 86% 1.600 0.050 97%

Average 96% 82% 94%

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Cost Analysis

• Economic Reasonability Test

• Enhanced Filtration Most Cost Effective

• Data Gap = Full-Scale Performance Under Dynamic Conditions

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Demonstration ofEnhanced Filtration• NSRP Sponsored Project at NASSCO Shipyard

• Test Three Grain-Size Distributions of Compost Media During Multiple Storms

• Treat 95% of the Runoff from Approximately10 Acres

• Design Completed 2000

• Construction Completed 2001

• First Test (Artificial Storm) September 2001

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Self-Cleaning Filter Cartridge

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Conclusions• A Cost-Effective Technology is Needed

to Control Shipyard Stormwater.

• Organic-Based Filtration is a Viable Alternative Based on Lab-Scale Tests

• Full-Scale Demonstration is On-Going at NASSCO Shipyard.

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Lydia Frenzel Conference Series - Advisory Council