Groundwater最新文献

Groundwater Week 2023 took place December 5–7, 2023 in Las Vegas, Nevada, and drew its largest attendance in the history of NGWA.

The annual event saw 6642 groundwater professionals take part, making it the biggest show in the Association history. Attendees came from 40 countries and all 50 states. The second largest show took place in 2006 with 6612 attendees.

“We're proud to have celebrated our 75th anniversary with the largest ever show attendance and thank everyone for making this historical milestone possible,” said NGWA CEO Terry S. Morse, CAE, CIC. “The groundwater industry is essential and, as such, extremely busy. We appreciate everyone taking time out of their busy schedules to be at Groundwater Week 2023.”

NGWA celebrated 75 years of serving groundwater professionals with a booth on the exhibit hall floor. NGWA past presidents and former staff members who helped the Association reach the milestone were in attendance to celebrate the occasion. A closing party, “Popcorn and Pilsners,” wrapped up Groundwater Week 2023 in the exhibit hall.

Attendees took in nearly 40 water well contractor workshops and visited 303 exhibitors on a crowded exhibit hall floor. Dozens of educational sessions in the Science & Engineering Forum took place concurrently. There was a total of 81,600 square feet of exhibit space, the most in NGWA history.

The groundwater industry's top concern—workforce development—was covered in a variety of workshops, including a roundtable discussion on passing knowledge to the next generation. Two certified industry veterans and one younger professional shared what has worked for them over the years in recruiting, hiring, and maintaining their employees.

For the second consecutive year, two events took place to aid young and early-career groundwater professionals. A tour of the exhibit hall led by seasoned groundwater veterans took place explaining how the tools and machinery seen on the floor are used daily in the industry. There was also a coffee and continental breakfast where young people had a chance to meet and network with each other.

Chip Nelson of GEFCO/BAUER Equipment America Inc. in Conroe, Texas, was elected to the secretary position on the Manufacturers Section Board and will also serve as a director on the NGWA Board of Directors.

Jeffrey Davis, PE, CGWP, was elected to the vice chair position on the Scientists and Engineers Section Board and will also serve as a director on the NGWA Board of Directors.

David Traut, MGWC, CVCLD, of Traut Companies in St. Joseph, Minnesota, became the NGWA president.

For the first time, NGWA elected someone from the Manufacturers Section as president-elect— Eric Macias of LORENTZ U.S. Corp. in Slaton, Texas.

The coastal zone, which is the interface between land and sea, is hydrodynamically very active due to the complex interactions of various hydrological controls and variable-density fluids. These forces vary over time, resulting in a state of dynamic equilibrium in the system. The major hydrological processes in coastal aquifer systems are salt water intrusion and submarine groundwater discharge, which are interdependent. Monitoring these complex processes is crucial for sustainable coastal zone management but poses a significant research challenge. In this study, we demonstrate the effectiveness of non-invasive geophysical techniques, specifically the time-lapse electrical resistivity imaging method, in conjunction with groundwater monitoring, for monitoring coastal groundwater dynamics in an unconfined aquifer at varying time scales and hydrogeological settings present at formerly glaciated sites worldwide. We generated two-dimensional baseline salt water intrusion maps for the test site, located on the coast of Rhode Island, USA. The time-lapse electrical resistivity survey method enables the rapid estimation of fresh groundwater discharge. Our approach offers insight into the mechanisms and seasonably variable salt water–freshwater interactions in unconfined heterogeneous aquifers. Although the results are site-specific, their implications are broad and may stimulate other studies related to sea to land pollution (sea water intrusion) and land to sea pollution (groundwater discharge) in heterogeneous coastal aquifer settings.

Coastal aquifers with high hydraulic conductivities on the order of 10⁻² m s⁻¹ have unconventional salinity distributions with the presence of non-fresh groundwater at the water table over a wide swath near the coast. This study aims to unravel the mechanisms underlying the phenomenon via numerical simulations for variably saturated, density-driven flow and solute transport in porous media. The simulation results indicate that the existence of non-fresh groundwater at the water table is attributed to the upward mass flux in the saturated zone near the coast, which transports solute from deeper groundwater toward the water table. With high hydraulic conductivity, the upward mass flux becomes prominent at shallower elevations because of the high Darcy flux and the shallow saline groundwater. The upward mass flux has two main drivers, upward advection by the upward flow component and transverse dispersion by the seaward flow component. The advective mass flux dominates over the transverse dispersion in the deep part of the saturated zone where only groundwater with sea water salinity exists. In contrast, the transverse dispersion becomes more pronounced than the upward advection in the shallow saturated zone just beneath the water table and in the unsaturated zone immediately above the water table. Our findings help interpret the unconventional salinity distributions observed and elucidate the unique dynamics of groundwater flow and solute transport in highly permeable coastal aquifers.