Closing CCR Impoundments with Confidence: Advanced Techniques for Compliance, Performance, and Risk Management

As utilities advance corrective action programs to meet CCR Rule requirements, integrated closure strategies whether closure-by-removal (CBR) or hybrid/traditional approaches (HCIP and CIP) are essential for addressing groundwater impacts associated with coal combustion residual (CCR) impoundments. Beyond regulatory compliance, the industry is increasingly focused on solutions that deliver measurable environmental benefits, optimize groundwater remediation timeframes, and reduce lifecycle costs. This presentation introduces an innovative methodology for CCR pond closure that combines robust engineering principles with practical implementation strategies. The approach leverages advanced geotechnical characterization and adaptive bridging techniques over soft subgrades, while beneficially incorporating CCRs to support structural stability. Real-time monitoring and rapid instrumentation feedback loops informed risk-based design decisions, enabling dynamic adjustments during construction. Novel material blends including lightweight structural fills and high-performance geosynthetics were deployed to safely close low-strength impoundments with minimal disturbance. Field results demonstrate how integrated modeling, optimized construction sequencing, and proactive water management through decanting and dewatering systems can accelerate closure schedules, mitigate groundwater impacts, and establish resilient post-closure frameworks. Highlighted case studies will offer replicable methods, data-driven insights, and lessons learned that utilities could apply to both small (<40 acres) and large multi-unit systems spanning hundreds of acres. Attendees will gain practical strategies for achieving compliance while advancing sustainability and long-term performance objectives.