35 FEBRUARY 2025 WorldWide Drilling Resource® In Memoriam Keil Albert (1968~2024) The California Groundwater Association (CGA) is mourning the loss of member Keil Albert on December 3, 2024. Born in Mountain View, he grew up in Sunnyside, attended Harker Academy, Bellarmine Prep, and Sonoma State University. After graduating in 1994 with a bachelor of science degree in geology, Keil began a successful career at GeoConsultants, Inc., in San Jose. There, he rose to CEO and managed business operations, also serving as the key contact in field operations. In 2017, he was honored with the Jeremy C. Wire Award as CGA Technical Member of the Year. He will be greatly missed by his family in California, Colorado, and Texas, his bowling community, college friends, fantasy sports league players, and especially by his beloved son Ryan. The management and staff of WWDR extend their sincere condolences to Keil’s family, friends, and former colleagues. Lest we forget . . . Four Ways to Collect Deep Groundwater Samples Adapted from Information by Cascade Environmental When it comes to gathering data on subsurface conditions and sites for environmental services projects, selecting the right deep groundwater sampling method can be overwhelming. It’s crucial to consider several factors such as budget, suspected contaminants, borehole size, quantity of sample required, and drilling method to choose the best technique and achieve the desired results. There are different deep groundwater sampling methods, focusing on those that use the casing advance drilling system for deeper applications, while excluding direct-push technology which is excellent for shallow applications. Temporary well installation involves a small-diameter casing with a perforated section at the bottom, a filter, sand, and a pulling mechanism to create a well for groundwater sampling. This is often used in boreholes and consists of a solid riser, well screen, and bottom point or cap. The installation process involves driving the casing to the desired depth, advancing the small-diameter PVC through the casing, and extracting the casing from the subsurface, leaving the expendable point and PVC behind. This method can be more time-consuming and costly compared to other methods, with additional costs for temporary well materials and potential water disposal if contamination is present. The Isoflow® tool is used to obtain high-quality discrete groundwater samples during drilling. It involves the use of a small stainless steel screen and a packer assembly. When the outer casing is pulled back, it is lowered into the casing to the bottom of the hole, sealing the tool and allowing only groundwater to flow through the screen. Push ahead samplers, also known as Hydropunch™ tools, are used to collect groundwater samples without disrupting the drilling process. The device is driven ahead of the drilling operation and then pulled back to expose a screen for sample collection. This approach is suitable for homogeneous formations like sand and gravel zones, and is effective in minimizing cross contamination. Push groundwater sampling is a simple, efficient, and cost-effective approach when the priority is keeping the cost of collecting discrete groundwater samples low and turbidity is not a concern. However, it’s important to have a good understanding of the subsurface formation and aquifer hydraulics. The SimulProbe® is a versatile tool for collecting both soil and groundwater samples from the same borehole. It uses a sheath to line the driven end of the sampler and small-diameter tubes for groundwater collection, making it ideal for sites requiring multiple sample types. The setup is time-consuming and it is more expensive compared to other samplers. These four deep groundwater sampling methods are some of the most frequently used, but it’s worth noting there are other options available as well. When selecting environmental sampling methods for your project, not all options are created equal. Consider the strengths and weaknesses of each method, particularly in relation to the lithologies you’re working with. Doing so can help you make an informed decision for the next project site. Photos courtesy of the United States Geological Survey. WTR
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