The most common method of HydraSleeve retrieval is the continuous pull method. You simply retrieve the HydraSleeve with one long upward motion at a rate of approximately 1 foot per second. This creates a core of water that enters the bag when it travels through the screen zone. When the bag is full, the check valve closes and allows no additional water into the bag.
Here we would like to discuss the other options which involve oscillating the HydraSleeve within the screen zone. These cycling methods allow the sleeve to fill in a shorter distance and can be used for sampling screens that are shorter than recommended for the continuous pull method.
Video demonstration of HydraSleeve cycling and bailer cycling
Some think that this will increase turbidity in your sample by stirring up the bottom the the well. While that may be true for a bailer, it is not what happens using a HydraSleeve. Please click on the image above to see a video demonstration that shows the difference between oscillating the HydraSleeve in a clear column with sediment in the bottom vs. the same experiment using a bailer.
There are two HydraSleeve cycling options - both of these are explained in our field manual as follows:
