Evaluating the Cost-Effectiveness of Environmental Protection Plans in Quarrying Using the Social Return on Investment Framework

Environmental Protection Plans (EPPs) are vital for mitigating the socio-ecological impacts of quarry operations, especially in emerging economies like Thailand, where rapid industrialization often intensifies air, water, noise, and land degradation. This study applies the social return on investment (SROI) framework to evaluate the cost-effectiveness of multi-domain EPPs implemented in a quarry. By applying compliance-based assessment and monetization of environmental and health co-benefits, annual economic outcomes were quantified for particulate matter (PM10), total dissolved solids (TDS), noise reduction, and carbon sequestration. The analysis revealed a high SROI ratio of 59.55:1, primarily driven by substantial health benefits from PM10 and noise abatement. This ratio also reflects consideration of investment from an annual operational cost, with a sensitivity analysis of incorporating an estimated capital expenditure, reducing the ratio to moderate value ranges of 5–10:1. A number of limitations, such as exclusion of capital costs, reliance on fixed proxies, and single-year scope, may overstate short-term returns, suggesting the application of stochastic methods for enhanced robustness. Overall, the findings demonstrate that EPPs deliver substantial economic and public health benefits, supporting their role in fostering community resilience and advancing sustainable operations in quarry sectors.