Water-Quality Changes During Cycle Tests at Aquifer Storage Recovery (ASR) Systems of South Florida

摘要

Water-quality changes were interpreted from existing cycle test data obtained from 11 treated surface-water Aquifer Storage Recovery (ASR) systems located in South Florida. Six ASR systems are located along the lower east coast (Palm Beach and Broward Counties), and five ASR systems are located in Lee and Collier Counties. These diverse data sets were the basis for interpretations of water-quality changes during ASR cycles in different regions. These data sets were interpreted to provide guidance for cycle test performance at Comprehensive Everglades Restoration Plan (CFRP) ASR pilot sites. ASR and monitoring well data were interpreted for trends in water-quality changes. Estimates of reaction rates or half-lives are based only on data obtained from monitoring wells during storage. Analytes that are reactants or products in major geochemical reactions are: dissolved oxygen, nitrate and ammonia, sulfate and hydrogen sulfide, gross alpha radioactivity and radium isotopes, and total trihalomethanes. Concentrations of these solutes in recovered water samples from recharge/ recovery wells were compared to state and Federal water quality regulations to identify regulatory exceedences. Concentrations of arsenic and gross alpha in recovered water sometimes exceeded regulatory criteria at ASR sites in Southwest Florida.