Passive sampling of groundwater wells for determination of water chemistry

Abstract

A series of nylon screen samplers retrieved from a profile of the water column of a well showing capped bottles and the removed tops. The variation of iron-staining on the removed tops indicates stratified flow with different redox conditions occurs under ambient flow conditions in the well. Photograph by Philip T. Harte, U.S. Geological Survey. (F) Figure 5A from report, a polyethylene diffusion bag sampler. Photograph by Bradley P. Varhol, EON Products, Inc. (G) Figure 9 from report, a rigid porous polyethylene sampler, without protective mesh and with protective mesh, in a water-filled tube for shipment. Photographs by Leslie Venegas, ALS Global. (H) Figure 13A from report, QED Environmental Systems, Inc. Snap Sampler® with volatile organic compound bottle (40-milliliter vial). Photograph by Sanford Britt, QED Environmental Systems, Inc.

In Situ Enhancement and Isotopic Labeling of Biogenic Coalbed Methane

“…After pumping approximately three wellbore volumes of water (500 L) 105 days prior to the injection, methane increased from 51.8 to 153.7 mg/L (94.2 mg/L above the baseline, as measured by Micro-TDGP) and returned to the baseline approximately ∼100 days after pumping ceased (Figure ). Drastic increases in dissolved gas due to gas migrating to the wellbore as a result of decreased pressure from pumping have been reported previously; , however, to the authors’ knowledge, this is the first long-term report indicating the length of time needed to reach baseline prepumped levels. This long-term analysis indicates that following the standard three-wellbore-volume purging method prior to sampling dissolved gas for quantitative analysis could provide an overestimate of the in situ methane concentration for months following pumping. , …”

“…Investigating the isotopic changes in downhole fluids (e.g., water and methane gas) over time from deuterium addition requires advanced sampling procedures devoid of groundwater pumping, which would remove injected deuterium and impact subsequent samples. These new downhole (nonpumped) sampling technologies have provided critical insight into subsurface microbial communities generating methane and in situ geochemical changes. − However, what remains a key gap is the suitability and accuracy of these recent advances for measuring methane concentration in the subsurface.…”

Evaluation and application of the Purge Analyzer Tool (PAT) to determine in-well flow and purge criteria for sampling monitoring wells at the Stringfellow Superfund site in Jurupa Valley, California, in 2017

“…Membranes differed for the two types of samplers. The RPP samplers were used to collect perchlorate samples; perchlorate is a large anion and can diffuse or transport through the RPP sampler (Parsons Engineering Science, Inc., 2005;Interstate Technology andRegulatory Council, 2006, 2007;Imbrigiotta and Harte, 2020). PDB samplers were used to collect volatile organic compounds (VOCs) such as TCE (Vroblesky, 2001a, b).…”

Distribution of chlorinated volatile organic compounds and per- and polyfluoroalkyl substances in monitoring wells at the former Naval Air Warfare Center, West Trenton, New Jersey, 2014–17

“…Other wells were sampled with polyethylene diffusion bag samplers or regenerated cellulose dialysis membrane (RCDM) diffusion samplers. These passive samplers were constructed and deployed using the procedures detailed in Imbrigiotta and others (2008) and Imbrigiotta and Harte (2020). Passive samplers were equilibrated in each well for approximately 2 weeks prior to retrieval and sample collection.…”

“…Samples were also collected on a test basis from five wells for PFAS compounds using RCDM passive samplers. RCDM passive samplers were constructed, deployed, and sampled using the procedures detailed in Imbrigiotta and others (2008) and Imbrigiotta and Harte (2020). The RCDM samplers were equilibrated in the wells for 3 weeks prior to retrieval and sampling.…”