Tips and Tricks

We would like to cover some basics for the use of HydraSleeves/SuperSleeves with top weights.   

First and most importantly, why would you want to use a top weight? 

     Top weights are used to compress the HydraSleeve or SuperSleeve into the bottom of the well.  This allows the sample collection process to begin at the deepest point possible in the well.   The compression of the HydraSleeve into the bottom of the well allows for the maximum sample volume to be recovered from short water columns.

Important things to consider when using one of our top weights:

1. A bottom weight must be used in conjunction with the top weight.  This allows for the sleeve to reach the bottom in a striaght and uniform manner before the compression begins.
2. Slack must be left in the tether to allow for the compression.  You should leave at least the length of the sampler and more if possible.  So we suggest 3-10 feet depending on the particular HydraSleeve or SuperSleeve being used.
3. Equilibration time is longer.  First you must allow time for the HydraSleeve to compress in the well.  This usually takes 24-48 hours.  You should also consider that top-weighted HydraSleeves will disturb the water column much more so than a standard bottom-weighted HydraSleeve.  Therefore, it will take the well longer to return to ambient conditions when using a top-weighted Hydrasleeve.  Please consider leaving all top weighted units up to 3 days before retrieval.

Please see our top-weighted HydraSleeve/SuperSleeve videos for more information.

Random photos from our recent photo contest....

HydraSleeves in action 

We are often asked what do regulators think of using HydraSleeves, or how is no-purge sampling accepted by some specific agency.  Well, we can tell you with confidence that there is growing acceptance for the use of HydraSleeves in all states, please read more here.  Not only that, but HydraSleeves are being used directly by the following governments and agencies that we know of.  There are likely more who use them through their consultants, but these are direct end users:

Arizona Public Service

California Department of Water Resources

Calaveras County, California

Clark County, Kansas, Landfill

Clark County, Nevada

EPA, Denver

Illinois EPA, Bureau of Land

Kansas Department of Health & the Environment

Las Cruces, City of

Maryland Environmental Services

New Mexico Bureau of Geology

Tucson, City of

U.S. Army Cold Region

USGS, Nashville

USGS, Massachusettes

USGS, Missouri

USGS, Tucson

Utah Department of Environmental Quality

Wyoming Department of Environmental Quality

Yuba County Water Agency, Marysville, California

This growing list is a good example of how the use of HydraSleeves have expanded throughout the United States.  The following map still applies.  If you know of any changes to the acceptance of no-purge sampling in your area, we would be happy to hear about it.  Simply drop us anThis email address is being protected from spambots. You need JavaScript enabled to view it.and we will be happy to research a change.

One of the most frequently asked questions about the HydraSleeve is:  "How long does it take for the well to equilibrate or restabilize after the HydraSleeve has been placed in the well?"  Unlike Passive Diffusion Bags, the HydraSleeve does not need time for the diffusion process to equilibrate.

Of course there is no one correct answer for every application, it varies and depends on many well-specific conditions such as recovery rate, flow-through characteristics for the aquifer and well screen,  the size of the well compared to the size of the HydraSleeve being used, and most importantly how much water is displaced during the placement of the HydraSleeve.  For more detailed information on this topic, please follow this link.

Since the weight is the heaviest and largest item being deployed, we thought it would be helpful to provide the displacement information based on the available bottom weights we offer.  The flat, ribbon-like HydraSleeve, itself, displaces very little when empty.

As you can see very little water is displaced when using even the heaviest of our bottom weights.  So using this information and the knowledge of your well should allow for an educated idea of how long to leave the first HydraSleeve deployment before retrieving them.  Top-weighted HydraSleeves and SuperSleeve assemblies substantially displace more water than a typical bottom-weighted set up; they also require time to allow for the compression of the HydraSleeve into the bottom of the well, so more equilibration time will be necessary for these types of assemblies.  Please see this link for a discussion on top weights.

Dye tests have shown that there will be only 3 inches of drag down in a 4-inch column when a 2-inch HydraSleeve is deployed; and there will be 2-feet of drag down in a 2-inch well when a 2-inch HydraSleeve is deployed. 

Most HydraSleeve groundwater sampling sites allow for leaving the HydraSleeves in the wells between sampling events, so this equilibration time is usually only considered during the very first deployment.  We also now have 2-inch HydraSleeves SpeedBags which are designed to minimize drag down and can retrieved immediately after installing.  Here's more information on the NEW SpeedBags.

Please give us a call (800-996-2225) or This email address is being protected from spambots. You need JavaScript enabled to view it. if you have any questions.