|
SUGGESTED METHODS ON THE APPLICATION OF BENTONITE FOR
SEALING PONDS
The procedures for applying bentonite in the dry form
is simple. All that is required is a system that will uniformly spread
the bentonite over the surface of the ground, work it into the soil and
compact it.
The Pure Blanket Method
This method is used when there is a high percentage of
water loss through seepage. This method can be done without specialized
equipment and without any previous experience in the use of bentonite.
1. This method requires that
the reservoir be drained.
2. The area in question should be prepared
adequately by the removal of boulders, vegetation, etc.
3. Using a blade or front-end loader, remover 3
to 4 inches of material from the bottom. store this material on the
banks for
future usage.
4. Holes or crevices should be filled with a
mixture of five parts soil and one part bentonite.
5. Level the reservoir bottom to eliminate any
deep furrows or surface irregularities.
6. Then lay a continuous blanket of bentonite
using a guide line of 1.25 Kgs. per square foot. This will usually
suffice most
conditions.
7. Pack the bentonite and re-apply the material
stored on the banks.
8. Pack the surface to near original density of
the soil.
9. Allow the water to flow gently into the
reservoir.
The Mixed Blanket Method
The bentonite may be applied in the mixed blanket
method without specialized equipment an without any previous experience
in the use of this material.
1. This method requires that the reservoir be drained,
if applicable.
2. The area in question should be prepared adequately by the removal of
boulders, vegetation, etc.
3. Using a blade or front-end loader, remove 3 to 4 inches of
material from the bottom. Store this material on the banks for future
usage.
4. Holes or crevices should should be filled with a mixture of
five parts soil and one part bentonite.
5. Level the reservoir bottom to eliminate any deep furrows or
surface irregularities.
6. Mark off the area to be covered into 10 feet by 10 feet (10' x
10') square sections with twine or stakes.
7. Then spread the bentonite over the surface evenly. Allow
200-250 Kgs of bentonite per square (10' x 10').
8. The bentonite is the worked into the top six inches of soil with a
disc or rototiller. By making several passes in each direction, a
homogeneous soil/bentonite system is obtained.
9. It is necessary to compact the soil/bentonite mixture as much as
possible. This of course permits the bentonite to be pressed
tightly into the voids in the soil which enhances the efficiency of the
seal.
10. Re-apply the material stored on the banks evenly over the
soil/bentonite liner and pack.
11. Allow the water to flow gently into the reservoir.
In the design of reservoirs it is important to bear in
mind certain criteria - the slopes are of critical importance. Side
slopes that are too steep - anything steeper than 2 to 1 for example,
cannot be effectively handled with bentonite since it is difficult to
place and retain the Bentonite on the side slopes.
The reservoir is now ready for use, provided care has been taken to
ensure the areas of potential erosion, such as the incoming water flow,
areas of wave erosion or if waders or livestock frequent the pond, have
been protected by a rock bed or concrete pads and/or a thick layer of
native soil (4" to 6") is covering the soil/bentonite seal.
Sprinkle Method
If a reservoir cannot be drained, or when only
portions of it need treatment, seepage can be halted by sprinkling
granular bentonite over the surface of the water.
1. Using rope or twine grids, mark off
the surface area into 10 foot by 10 foot squares (10' x 10').
2. Scatter the bentonite at the rate of 100
pounds per 10 foot by 10 foot (10' x 10') square.
Granular bentonite is used because the particles will
drop to the bottom before they complete their swelling and gelling
action. The bentonite is drawn into the cracks and crevices where
leakage takes place, thereby halting the leakage. This method generates
a slight cloudiness of the water but is not harmful for drinking
purposes.
In summary, the use of bentonite as a soil sealant is one of the oldest
means of sealing water reservoirs. Use of this product is enjoying a
resurgence due to recognition of it's favorable economics, ease of
application and versatility. Also, being a natural
material, the bentonite will in no way pollute the stored water or the
surrounding environment
ccp@canadianclay.com
P.O. Box 70
Wilcox, Saskatchewan S0G 5E0
Phone: (306)732-2085
Fax: (306)732-2100
Hours: 8:00 a.m. to 4:30 p.m.
|