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Cadmium and Hexavalent Chromium Alternatives 5-Year Strategy and Roadmap, Contract # W9128F-12-D-0041

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Cadmium and Hexavalent Chromium Alternatives 5-Year Strategy and Roadmap, Contract # W9128F-12-D-0041 Cadmium and Hexavalent Chromium Alternatives 5-Year Strategy and Roadmap, Contract # W9128F-12-D-0041 25 May 2016 3150 Fairview Park Drive South Falls Church, Virginia 22042-4519 Cadmium and Hexavalent Chromium Alternatives 5-Year Strategy and Roadmap, Contract #W9128F-12-D-0041 Executive Summary The Strategic Environmental Research and Development Program (SERDP) and Environmental Security Technology Certification Program (ESTCP) Weapons Systems and Platforms Program Area has developed a strategy to reduce use of cadmium (Cd) and hexavalent chromium (Cr6+) by 90% or more at Department of Defense (DoD) maintenance depots over the next five years. The strategy includes objectives, metrics, and actions to demonstrate how this reduction can be achieved. The strategy employs site demonstrations and leverages DoD resources to replicate processes across the DoD depot community. It also includes a recommended future path for success in the advanced coatings area. As part of this effort, installation-specific implementation plans were developed in coordination with Letterkenny Army Depot (LEAD), Fleet Readiness Center Southeast (FRCSE), and Oklahoma City Air Logistics Complex (OC-ALC). These efforts helped inform the strategy. These implementation plans track to the overall Advanced Coating 5-Year Strategy and Roadmap, consist with DoD’s strategic vision as it pertains to Cr6+ and Cd reduction. DoD processes that contribute to current cadmium and hexavalent chromium use and production, and potential alternatives are illustrated in Figure ES-1. DoD Processes Chromate Topcoats and Chromated Cadmium Stainless Steel Adhesives and Cadmium Brush Coatings Stainless Steel Chrome Plating Conversion Chrome Sealers Specialty Primers Plating Passivation Sealants Plating Removal Welding Coatings Coatings Rare Earth and TCP Conversion Zn-Ni Brush TCP Anodize Non-Chrome other Metal HVOF An-NI Plating Citric Acid Laser Removal Coatings Plating Sealers Consumables Primers Mag_Rich Shield Gas nCoPl AlumiPlate Boegel/Sol-Gel Sol-Gel FlashJet Primters Modification Trivalent IVD Aluminum PreKote Other Other Chromium Other DoD Process DoD Alternative Figure ES-1. DoD Cd and Cr6+ Process and Alternatives Cr6+ and Cd-reduction initiatives have been prioritized using a relative scoring methodology. Four metrics were utilized in the prioritization process: 1) Impact to Readiness; 2) Likelihood of Implementation; 3) Return on Investment; and 4) Impact to Goals. Each metric was scored based on qualitative measures. After scoring, reduction initiatives were grouped into tiers based on how essential the alternative process is to achieving the ultimate goal of the strategy. ES-1 Cadmium and Hexavalent Chromium Alternatives 5-Year Strategy and Roadmap, Contract #W9128F-12-D-0041 Tier 1 priority initiatives are critical to achieving Cr6+ and Cd reduction goals. These initiatives must be successfully implemented for reduction goals to be achieved. These initiatives typically impact other depots, and address similar critical usages, emissions, exposures, and/or waste streams at multiple locations. Tier 1 priority initiatives typically have a significant impact to readiness, though this is not always the case. The ten (10) initiatives considered Tier 1 priorities are: • Non-Chromate Primer on Aircraft OML • Non-Chromate Primer on Aircraft non-OML Surfaces • Non-Chromate Primer on Off-Aircraft Components and Commodities • HAP-Free, Non-Cr6+ Wash Primer • Alternative to Chrome Plating • Alternative to Cadmium Plating • Non-Chrome Chemical Conversion Coatings for Aluminum • Alternative to Cadmium Brush Plating • Alternative Coatings Removal Processes to Reduce Cr6+-Containing Waste Streams • Implementation of Engineering Controls for Stainless Steel Welding Operations Tier 2 priority initiatives are not critical to achieving DoD Cr6+ and Cd reduction goals, but these initiatives nevertheless address significant usages, emissions, exposures, and/or waste streams. These initiatives may impact similar processes at other depots, increasing their value and return on investment. Tier 2 initiatives typically have a moderate impact to readiness, and may also exhibit strong ROIs. The four (4) initiatives considered Tier 2 priorities are: • Non-Chrome Stainless Steel Passivation • Alternative to Dichromate Sealers in Anodizing Operations • Non-Chromated Coatings Removal Alternatives • Non-Chrome Consumables for Stainless Steel Welding Tier 3 priority initiatives are not critical to achieving Cr6+ and Cd reduction goals and address usages, emissions, exposures, and/or waste streams to a lesser degree than those identified in Tiers 1 and 2. Tier 3 initiatives have a minor impact, and in fact, may not warrant expending resources to implement them. Tier 3 initiatives are typically localized, impacting only a single location with little impact to readiness. The fourteen (14) initiatives considered Tier 3 priorities are: • Non-Chrome Chemical Conversion Coatings for Magnesium • Non-Chrome Sealants for Aerospace Applications • Non-Chrome Structural Adhesives for Defense Applications • Alternative to Dichromate Sealers for Brush Plating Finishes • Alternative to Dichromate Sealers for Black Oxide and Phosphate Finishes • Non-Chrome Aluminized Coating for Aircraft Engine Applications • Non-Chrome Anodized Dyes • Non-Chrome Conductive EMI Coating • Non-Cadmium Silk Screen Ink ES-2 Cadmium and Hexavalent Chromium Alternatives 5-Year Strategy and Roadmap, Contract #W9128F-12-D-0041 • Non-Cadmium Safety Paint • Non Chrome Desmutting/Deoxidizing Alternatives • Robotic Painting to Reduce Worker Exposure and Increase Maintenance Efficiency • Reducing Emissions and Exposure from Chromated Adhesives and Sealants • Reduction of Emissions, Waste, and Exposures Associated with Cadmium Brush Plating Most of DoD’s Cr6+ and Cd usage, emissions, exposure, and waste stream reduction goals can likely be met by leveraging and expanding ongoing or past initiatives. In fact, 90% reduction in Cr6+ and Cd usage can be achieved through implementation of Tier 1 priority initiatives alone, most leveraging ongoing work either within the DoD or Original Equipment Manufacturers (OEM). ES-3 Cadmium and Hexavalent Chromium Alternatives 5-Year Strategy and Roadmap, Contract #W9128F-12-D-0041 Table of Contents Executive Summary ................................................................................................................ ES-1 List of Acronyms .......................................................................................................................... iii 1. Introduction ............................................................................................................................. 1 1.1. Background ................................................................................................................................... 1 1.2. Regulatory Drivers ....................................................................................................................... 2 2. Problem Definition .................................................................................................................. 2 2.1. Processes ........................................................................................................................................ 2 2.2. Usage/Waste/Emissions/Exposures ............................................................................................. 5 2.3. Weapon Systems and Platforms .................................................................................................. 7 3. Strategy .................................................................................................................................... 7 3.1. Goals .............................................................................................................................................. 7 3.3.1 Goal 1 – Reduce the use of Cd and Cr6+ containing compounds in DoD depots by 90% within 5 years ...................................................................................................... 7 3.3.2 Goal 2 – Reduce Cd and Cr6+ emissions, waste streams, and exposure potential in DoD depots by 90% within 5 years ............................................................................. 7 3.2. Objectives/Success Metrics .......................................................................................................... 7 3.3. Actions ......................................................................................................................................... 16 3.3.3 Tier 1 Priority Actions ..................................................................................................... 16 3.3.4 Tier 2 Priority Actions ..................................................................................................... 23 3.3.5 Tier 3 Priority Actions ..................................................................................................... 24 Appendix A – Processes ............................................................................................................ A-1 Chromated Primers .......................................................................................................................... A-1 Chromated Wash Primers ............................................................................................................... A-1 Chrome Plating ................................................................................................................................. A-2 Cadmium Plating
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