Karst aquifers occur worldwide and exhibit groundwater flow responses that differ considerably from aquifers lacking fractures, bedding planes, and other karst conduits where significant and rapid groundwater flow can...Karst aquifers occur worldwide and exhibit groundwater flow responses that differ considerably from aquifers lacking fractures, bedding planes, and other karst conduits where significant and rapid groundwater flow can occur. The regional, karst Floridan aquifer system underlies the United States (US) Southeastern Coastal Plain Physiographic Region and exhibits hydrologic interconnections with overlying surficial aquifers and throughout other zones of the aquifer system, as is characteristic of other karst aquifer systems. Anthropogenic groundwater declines in this regional karst aquifer system have been documented in published literature for decades, but the impacts of those declines in this coastal plain region and the embedded ecosystems that provide essential and critical habitat for native, endemic, and federally endangered and threatened species have not been considered previously. Those anthropogenic groundwater declines reduce surfacewater levels and flows due to the capture of both groundwater and overland flow of surfacewater, resulting in induced recharge through semi-confining zones and interbasin flow through fractures and other karst conduits. This case study identifies examples from the Greater Okefenokee Swamp Basin study area and comparison areas of how those declines result in loss of historic base flow to surface waters and other capture of surface waters, ultimately increasing saltwater intrusion. Those results alter and degrade the physical, chemical, and biological integrity of the nation’s waters, in violation of the US Clean Water Act (CWA) of 1972. Historic groundwater declines from mining and other anthropogenic groundwater withdrawals from this regional karst aquifer system already threaten the survival and recovery of federally endangered and threatened species, as well as existing and proposed critical habitat for those species within this regional extent, in violation of the Endangered Species Act (ESA) of 1973. This case study and its companion publication (Part 2) appear to be the展开更多
文摘Karst aquifers occur worldwide and exhibit groundwater flow responses that differ considerably from aquifers lacking fractures, bedding planes, and other karst conduits where significant and rapid groundwater flow can occur. The regional, karst Floridan aquifer system underlies the United States (US) Southeastern Coastal Plain Physiographic Region and exhibits hydrologic interconnections with overlying surficial aquifers and throughout other zones of the aquifer system, as is characteristic of other karst aquifer systems. Anthropogenic groundwater declines in this regional karst aquifer system have been documented in published literature for decades, but the impacts of those declines in this coastal plain region and the embedded ecosystems that provide essential and critical habitat for native, endemic, and federally endangered and threatened species have not been considered previously. Those anthropogenic groundwater declines reduce surfacewater levels and flows due to the capture of both groundwater and overland flow of surfacewater, resulting in induced recharge through semi-confining zones and interbasin flow through fractures and other karst conduits. This case study identifies examples from the Greater Okefenokee Swamp Basin study area and comparison areas of how those declines result in loss of historic base flow to surface waters and other capture of surface waters, ultimately increasing saltwater intrusion. Those results alter and degrade the physical, chemical, and biological integrity of the nation’s waters, in violation of the US Clean Water Act (CWA) of 1972. Historic groundwater declines from mining and other anthropogenic groundwater withdrawals from this regional karst aquifer system already threaten the survival and recovery of federally endangered and threatened species, as well as existing and proposed critical habitat for those species within this regional extent, in violation of the Endangered Species Act (ESA) of 1973. This case study and its companion publication (Part 2) appear to be the