slug/logo.gif)
(click to enlarge)
Solid H(o) Slug Video
Guidelines for Improving the
Quality of Slug Tests
(from Butler, McElwee and Liu, 1996, see link below)
- Three or more slug tests per well
- Two or more Initial Displacements (H(o))
- Near-Instantaneous H(o)
- Appropriate data-acquisition equipment
- If storage parameter is needed, sufficient high-quality data is required
- Appropriate analytical solution and software
- Pre- and Post- Analysis Plots
- Consideration of subsurface conditions and well configuration
Professional Paper:
Butler, McElwee and Liu, NGWA, 1996
http://info.ngwa.org/
gwol/pdf/961561944.PDF
|
|
Pronounced: H naught slug
NOW SLUG TESTING IS EASIER THAN EVER!
The Solid H(o) Slug ® by Midwest GeoSciences Group is a traditional solid slug for slug testing. It is designed to yield a pre-estimated initial displacement in two-inch diameter wells for improving confidence and accuracy of slug testing.
Knowing your expected initial displacement BEFORE the slug test allows you to recognize problems, noise or technical difficulties DURING the test...and the allows you to correct your slug test for better results.
It's a new item available only through Midwest GeoSciences Group. You can choose between imperial or metric initial displacements to match your data collection methods and it's available now for common initial displacement lengths H(o)*:
| Imperial Units | Metric Units |
| 12 inch displacement | 30 centimeter displacement |
| 18 inch displacement | 45 centimeter displacement |
| 24 inch displacement | 60 centimeter displacement |
Three slug tests using at least two initial displacements are found to be best-practice standards and recommended by Jim Butler's book: The Design, Performance and Analysis of Slug Tests (see below) which has become the standard reference for slug testing around the world. Three initial displacements allow a measure of test performance and an estimation of the noise to data ratio during normalization of the data during analysis.
Engineered Design
The Solid H(o) Slug is specifically designed with tapered ends exceeding an 80 degree angle to reduce the pressure wave that can occur with other solid slugs leading to noisy data and reducing the reliabilty of test data.
slug/falling-head.gif)
Calculated initial displacement is represented by "H(o)*" where H is the calculated distance of instanteous change at time zero (o) in water level created by the the slug. "H(o)" is the measured initial displacement. It is important to compare calculated H(o)* with measured H(o) as part of the QA/QC of the slug test for checking the reliability of test data.
Solid H(o) Slug ®
-PVC Version
-Imperial or Metric Units
(order any combination)
-Pricing:
| 3 Slugs (or more): | $73.00 | each | | 2 Slugs: | $89.50 | each | | 1 Slug: | $119.00 | each |
Shipping Costs:
Use the chart below to calculate your shipping costs. Here's how to do it;
-for orders of 3 or less, simply use the chart for your locale
-for other orders, you'll need to do a little math. Some examples...
- say your order contains 4 slugs;
add the '3 rate for your locale' and the '1 rate for your locale'
- say your order contains 5 slugs;
add the '3 rate for your locale' and the '2 rate for your locale'
- say your order contains 6 slugs;
mulitply the '3 rate for your locale' by two
- say your order contains 7 slugs;
mulitply the '3 rate for your locale' by two and add the '1 rate for your locale'
FOR ANY 3:
-shipping in the US (except AK and HI): $68.00
-shipping in AK, HI, Canada: $145.00
-shipping outside the US and Canada: $295.00
FOR ANY 2:
-shipping in the US (except AK and HI): $38.00
-shipping in AK, HI, Canada: $105.00
-shipping outside the US and Canada: $265.00
FOR ANY 1:
-shipping in the US (except AK and HI): $28.00
-shipping in AK, HI, Canada: $95.00
-shipping outside the US and Canada: $235.00
"I purchased a set of the Solid H(o) and was very pleased working with Midwest Geosciences Group. They were helpful and provided detailed guidance for performing the slug tests using the Solid H(o) slugs. Slug testing performance and ease-of-use was as advertised providing quality K-value data for evaluation of a technically complex site with varied groundwater conditions."
- Alex Howe, PG, Senior Geologist, WSP, Inc.
"I am pleased with Midwest Geoscience's set of solid H(o) slugs. In my experience, one of the biggest issues with homemade PVC slugs is the water level disturbance that occurs upon slug insertion. This can be a significant problem, especially when testing a high-K formation. The tapered design of the solid H(o) slugs allows for minimal water level disturbance while also ensuring full slug submergence during testing. The low cost of the slugs combined with their effectiveness makes them a clear winner in comparison to homemade slugs."
- Thomas Nelson, PG, Principal Hydrogeologist,
ECS MID-ATLANTIC, LLC.
"Performing slug tests with the Midwest GeoSciences Group solid H(o) slugs are perfect for determining K-values efficiently. In my experience, H(o) values tend to fit better at well locations with low K values, however data is also reliable and accurate for wells with high K values. They are straight forward and easy to use."
- Christian Bruchman, Arcadis
|
slug/slugtesting-1.gif)
slug/aqtesolv.gif)
