A Modest Proposal: How can we remove 90% of Cadmium and Hexavalent Chromium used at DoD Depots?
Protecting military assets from the negative effects of corrosion is a significant effort for DoD. The extreme environments in which these assets are required to perform makes this effort especially challenging. Unfortunately, surface coatings containing hexavalent chromium (Cr6+, Cr(VI)) and cadmium (Cd) provide the best corrosion inhibiting properties but also have significant environmental and human health concerns. The SERDP and ESTCP Weapons Systems and Platforms (WP) Program Area recently developed and published the Advanced Coating 5-Year Strategy and Roadmap to eliminate >90% of the Cr6+ and Cd in use at DoD maintenance depots over the next 5 years. The strategy includes objectives, metrics, and actions to demonstrate how this reduction can be achieved through multiple site demonstrations, leveraging DoD resources to replicate processes across the Depot community, and developing a future path for success in the area of advanced coatings.
Paint Loss from Rivet Head – “Rivet Rash” (Source: Boeing).
As part of this effort, installation-specific implementation plans were developed in coordination with Letterkenny Army Depot, Fleet Readiness Center Southeast, and Oklahoma City Air Logistics Center. These implementation plans were used to inform the overall Strategy and Roadmap developed by SERDP and ESTCP, maintaining consistency with DoD’s strategic vision as it pertains to Cr6+ and Cd reduction. More information is available from a recent webinar discussing this work.
A critical step in the development of this strategy was the prioritization of Cr6+ and Cd-reduction initiatives using a relative scoring methodology. Four metrics were utilized in the prioritization process:
Each metric was scored based on qualitative measures. Reduction initiatives were tiered based on how essential the alternative process is to achieving the ultimate goal of the strategy.
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.
Tier 2 priority initiatives are not critical to achieving DoD Cr6+ and Cd reduction goals, but still 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.
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 results of this assessment indicate that 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 of these initiatives are currently leveraging ongoing work either within the DoD or Original Equipment Manufacturers. SERDP and ESTCP remain interested in funding new efforts to further reduce the use of Cr6+ and Cd from DoD Depots. Interested parties are advised to pay close attention to future solicitations to determine if work in the area is considered responsive. It is recommended that future proposals in this area be aligned with the findings outlined in this strategic plan.