Aquifer Storage and Recovery as a Viable Climate Change Adaptation Technique: Sustainable Development under the Current Regulatory Framework

A holistic investigation of aquifer storage and recovery (ASR) technique and application in the U.S. is being conducted as a part of the USEPA Water Resources Adaptation Program (WRAP). The research focus is to evaluate the potential of ASR application as a practical climate change adaptation tool. Specifically, the investigations are centered on ASR's technical feasibility, regulatory implications, and engineering techniques for field applications: 1) need for ASR to mitigate water budget imbalance; 2) environmental impacts and potential regulatory implications; and 3) adaptation techniques and engineering guidelines for sustainable ASR development. This paper describes the ASR research framework and the initial research results on the ASR needs and environmental consequences. In assessing the need in future climate, geographic regions with likely imbalance between water demand and water availability are identified. This analysis relies on a nationwide hydroclimatic study of historical and future precipitation changes, an evaluation of future water demand variations, and a hydrological analysis of candidate geological strata. The second part of the research was conducted to address how the ASR operations can be sustainable in avoiding environmental impacts to the storage media and groundwater quality. The results are critical for assessing the adequacy of current ASR engineering practices and regulations. Quantitative experimental studies have been conducted to study the presence of recalcitrant endocrine-disrupting compounds (EDCs) and aldicarb (as a model pesticide) in reclaimed water, evaluate their fate and transport at an ASR site, and to investigate arsenic remobilization and secondary arsenic contamination to groundwater. These deterministic studies were conducted using bench-scale and pilot-scale soil column experiments, activated sludge and membrane bioreactor for wastewater treatability studies, in situ atomic force microscopy of arsenic-bearing mineral dissolution, as well as two-dimensional ASR modeling of hydrologic and water quality kinetic processes. Preliminary research results show the ASR feasibility in water resource adaptation to climate changes, and have laid a technical basis for further developing ASR engineering techniques with managed environmental impacts.