02 February 2026

Slug Testing Guidance Like No Other

The Design, Performance, and Analysis of Slug Tests, Second Edition explains virtually all there is to know regarding the design, performance, and analysis of the most common well test for determining hydraulic conductivity: Slug Testing

The First Edition has become the standard reference for all aspects of slug tests. It has positively changed project outcomes and helped professionals become responsible stewards of our precious water resources by promoting best practices.

The Second Edition contains updated information and expands the focus with new developments where slug testing is applied in applications related to contaminant assessment.

Written for practicing groundwater consultants and engineers, The Design, Performance, and Analysis of Slug Tests, Second Edition enables readers to achieve more reliable information from slug tests and widen the application of this common field method.

Order your copy here and it will arrive with a personalized note from Dr. Butler!

https://midwestgeo.com/fieldtools/slugtest-book.php?item=901


15 January 2026

“Big-Big H(o)mer” credited to Carol Rieger PG, RPG, PMP

Hello Dan, Just wanted to thank you and Midwest Geosciences Group for the slugs we have purchased over the past 2 years.  Again, slug testing was a painless and positive experience using the Big H(o) slugs, especially supported by equipment from our buddies at In-Situ.  

We slug tested using a pulley system for with “Big-Big H(o)mer” and I still feel that manually we were able to raise and lower the slug more effectively to have less disturbance at the onset of each test.  Lessons learned will definitely help us improve the mechanical approach.  

As for “Little-Big H(o)mer”, he may not have provided as intense a workout, he but performed admirably. 

Carol with the "Big Big-H(o)mer"
(24 inch initial displacement H(o) in a 4-inch diameter well)

Aquifer testing has come a long way since my first time back in the early 90s.  Between the equipment and training class that you provided back in September 2023, our slug-testing capabilities have definitely improved here at the Rocky Mountain Arsenal.    

Cheers!  --Carol 

Carol Rieger, PG, RPG, PMP, Program Hydrogeologist
Navarro Research and Engineering, Inc., Rocky Mountain Arsenal
7270 Kingston Parkway, Commerce City, CO 80022

Dear Carol,
Your note with your photo make my day.  Thank you for leading the way with your technical mastery of slug testing.  And you get the credit and a "big" thank you for your creative naming of the "Big Big H(o)mer" for the solid slug that displaces 24 inches of water vs. "Little Big H(o)mer" for the solid slug that displaces 12 inches of water!  Brilliant creativity!
-Dan Kelleher