EnviroEquip Groundwater Seminar

Audience flows into seminars

Successful Seminar Series on Low-Flow Ground Water Sampling

28th August 2006
Matt Scaddan - Enviroequip Marketing

Over 350 people attended the latest series of industry seminars, organised by Enviroequip in Melbourne, Adelaide, Perth, Brisbane, Sydney and Auckland. Low-Flow Ground Water Sampling was the topic and the presenter was Mr David Kaminski of QED Environmental Systems. Mr Kaminski, an expert on groundwater sampling methods, received very positive feedback from the events.

Mr Kaminski covered a lot of material during the three hour seminar including how ground water sampling procedures were developed and a comparison of the common types of sampling methods. The Low-Flow Sampling Method was discussed in detail and was followed by a demonstration of the recommended equipment for best sampling.

Mr Kaminski showed that low-flow ground water sampling can improve sample accuracy and precision and avoid biases associated with turbid samples. The method provides flow-weighted average concentrations from typical monitoring wells, and is the best approach for determining the true mobile contaminant load in most monitoring scenarios.

The common misconception that low-flow samples represent a narrow zone within the screen was addressed. Field experiments, laboratory simulations and numerical modeling support the position that samples are derived from the entire screen zone under low-flow pumping conditions. Modeling also concludes that pump placement has no significant effect on the flow pattern into the well; geology is the controlling factor.

Purging very-low-yield wells was discussed. This applies to wells that cannot be pumped at low rates (100 ml/min) without continuous drawdown. "Minimum Purge Sampling" is less disruptive than well evacuation and minimizes sample chemistry alteration.

The three main steps of Low-Flow Sampling were presented and demonstrated:
1) Setting the purge flow rates
2) Controlling drawdown
3) Water quality parameter stabilisation

Download the presentation and referenced papers...

“Low-Flow Ground Water Sampling: An Update on Proper Application and Use” David Kaminski – QED Environmental Systems Inc. – Pleasant Hill, CA. August 2006 -- Download the presentation

References (listed in order cited during the presentation)

Wilson, L. C. and J. V. Rouse, 1983. “Variations in Water Quality during Initial Pumping of Monitoring Wells.” Ground Water Monitoring and Review, Vol. 3, No. 1, pp. 103-109.

Keely, J.F., and K. Boateng. 1987. Monitoring well installation, purging, and sampling techniques – Part 1: Conceptualizations. Ground Water, Vol. 25, no. 3, pp. 300-313.
Link - http://www.blackwell-synergy.com/doi/abs/10.1111/j.1745-6584.1987.tb02134.x?journalCode=gwat&volume=25&issue=3

Giddings, Todd, 1983. "Bore-Volume Purging to Improve Monitoring Well Performance: An Often-Mandated Myth." Proceedings of the NWWA Third National Symposium on Aquifer Restoration and Ground-Water Monitoring, Columbus, Ohio. May, 1983, pp. 253-256.

Schilling, Keith, 1995. “Low-Flow Purging Reduces Management of Contaminated Groundwater”. Environmental Protection. Vol. 6, No. 12. December 1995, pp. 24-26. Download

Heidlauf, David T. and Timothy R. Bartlett, 1993. “Effects of Monitoring Well Purge and Sample Techniques on the Concentration of Metal Analytes in Unfiltered Groundwater Samples.” Proceedings of the NGWA Outdoor Action Conference, Las Vegas, NV, May 1993, pp. 437-450.

Puls, Robert W. and Cynthia J. Paul, 1998. “Discrete-Level Ground-Water Monitoring System for Containment and Remedial Performance Assessment Objectives.” Journal of Environmental Engineering, June 1998, pp. 549-553. Download

Martin-Hayden, J.M. and G. A. Robbins, 1997. “Plume Distortion and Apparent Attenuation Due to Concentration Averaging in Monitoring Wells”. Ground Water, Vol. 35, No. 2, pp. 339-346. Download

Varljen, M. D., M. J. Barcelona, J. Obereiner and D. B. Kaminski, 2006. “Numerical Simulations to Assess the Monitoring Zone Achieved during Low-Flow Purging and Sampling.” Ground Water Monitoring and Remediation, Vol. 25, No. 1, pp. 44-52. Download

Puls, Robert W. and C. J. Paul, 1995. "Low-Flow Purging and Sampling of Ground Water Monitoring Wells with Dedicated Systems." Ground Water Monitoring and Remediation, Vol. 15, No. 1, pp. 116-123.

Puls, R.W. and M.J. Barcelona, 1996. “Low-Flow (Minimal Drawdown) Ground-water Sampling Procedures.” U.S. EPA, Ground Water Issue, Publication Number EPA/540/S-95/504, April 1996. Download

Vandenberg, P. and M.D. Varljen, 2000. “Low-Flow Purging and Sampling of Groundwater at a Solid Waste Landfill: Planning and Implementation.” Proceedings of the SWANA 15^th Annual Pacific Northwest Regional Symposium, Vancouver, B.C., April 2000. Download

Barcelona, Michael J., M.D. Varljen, R. W. Puls and D. B. Kaminski, 2005. “Ground-Water Purging and Sampling Methods: History vs. Hysteria.” Ground Water Monitoring and Remediation. Vol. 25, No. 1, pp. 52-62. Download

Barcelona, Michael J., H.A. Wehrmann, and M.D. Varljen, 1994. “Reproducible Well-Purging Procedures and VOC Stabilization Criteria for Ground-Water Sampling.” Ground Water. Vol. 32, No. 1, pp. 12-22. Download

Elci, A., F. J. Molz III and W. R. Waldrop. 2001. Implications of Observed and Simulated Ambient Flow in Monitoring Wells. Ground Water Vol. 39, No. 6, pp. 853-862.

Oneacre, J. and D. Figueras, 1996. “Ground Water Variability at Sanitary Landfills: Causes and Solutions.” In Proceedings of the ASCE Conference on Uncertainty in the Geologic Environment, Madison, Wisconsin, July 31-August 3, 1996, pp. 965-987. American Society of Civil Engineers.

Pohlmann, K.F., R. P. Blegen and J. W. Hess, 1991. "Field Comparison of Ground-Water Sampling Devices for Hazardous Waste Sites: An Evaluation Using Volatile Organic Compounds", U.S. EPA Publication # EPA/600/4-90/028, May 1991.

Chapelle, F. H., D. A. Vroblesky, J. C. Woodward and D. R. Lovely, 1997. “Practical Considerations for Measuring Hydrogen Concentrations in Groundwater.” Environmental Science and Technology, Vol. 31, No. 10, pp. 2873-2877. www

Florida Department of Environmental Protection, Standard Operating Procedure FS2200, “Ground Water Sampling”, June 2004. www

American Society for Testing and Materials (ASTM), Standard D6771, “D6771-02 Practice for Low-Flow Purging and Sampling for Wells and Devices Used for Ground-Water Quality Investigations ”. ASTM International, April 2003. (www.astm.org). www

"We’re detecting water
chemistry that we have never
measured
before with our previous methods "

Mining Support Company,
Tasmania

"Using the
low-flow
groundwater sampling
procedure with a
bladder pump
led to detection of VOCs at
levels that are very difficult to achieve with other
sampling devices".

Groundwater consultant,
Newcastle

"Faced with a
daunting sampling
program for
the life of the mine,
LowFlow was
the only cost-effective solution
that could deliver low
running costs and consistent high-quality
groundwater
samples..."

Mine Environmental Officer,
NSW

Links

Micropurge / Low-Flow Sampling Resource Page

Other Articles & Links

Micropurge / Low-Flow Sampling Resource Page
US EPA Ground Water Issue - Low-Flow (Minimal Drawdown) Ground-water Sampling Procedures. Download
ASTM -Practice for Low-Flow Purging and Sampling for Wells and Devices Used for Ground-Water Quality Investigations - www
Ritchie, J, 2002. "Low-Flow Purging and Sampling Ground Water - Evolution of Technology and Standards" ASTM Standardization News April 2002 pp. 18-23. Download
US EPA ETV Verification Statement QED Well Wizard - August 2000. Download
Gray, S., S. Light and M. Cloud, 1996. "Go with the Low Flow". The Military Engineer, October - November 1996, pp. 580-581. Download
Powell, Robert M. and Robert W. Puls, 1997. “Hitting the Bull’s-Eye in Groundwater Sampling.” Pollution Engineering, June 1997, pp. 50-54. Download
Puls, R.W. and M.J. Barcelona, 1989. “Ground Water Sampling for Metal Analyses” U.S. EPA, Ground Water Issue, Publication Number EPA/540/4-89/001, March 1989. Download
QED Environmental Systems web site www