| Monitored Zone | Channel Number | Depth to Center of Port (from ground surface) |
|---|---|---|
| 1 | 1 | 20 ft (6.1 m) |
| 2 | 2 | 30 ft (9.1 m) |
| 3 | 3 | 50 ft (15.2 m) |
In our example (Table 2) there are ports at 20 ft, 30 ft and 50 ft (6.1 m, 9.1 m and 15.2 m) depths. Each monitoring zone is 2 ft (0.6 m) length. Sand Cartridges are a nominal 1 ft (0.3 m) length, therefore, a total of six Sand Cartridges will be required to complete this installation. The annulus volume of filter sand required is about 0.015 cu.ft/ft (0.0014 cu.m/m) per Sand Cartridge, therefore, a 50 lb (23 kg) bag of sand will provide an ample 25 ft (7.6 m) of sand pack.
Note:
Each 50 lb (22.7 kg) bag of sand will fill about 25 ft (7.6 m) of sand cartridges.
In this example, we will use a 3 ft (0.9 m) bentonite seal on either side of our monitoring zone, with an exception at Port 3, the deepest. We chose not to place a bentonite seal below Port 3. Thus, three monitoring zones equates to five 3 ft (0.9 m) sealed areas. As the Bentonite Spring Cartridges are nominally 1 ft (0.9 m) in length, five seal locations, each 3 ft (0.9 m) long, mean fifteen Cartridges will be needed. Each Cartridge will require about 1 lb (0.5 kg) of 3/8" dia. bentonite pellets, therefore about 15 lbs (7.5 kg) is required.
Note:
Each Bentonite Spring Cartridge will require about 1 lb (0.5 kg) of 3/8" dia. bentonite pellets.
