and below the existing monitoring well.

     These two well nests consisted of three 1.91 cm (3/4 in) PVC

pipes taped together with nylon reinforced tape.      The threaded

joint pipes were screened with 30.48 cm (1 ft), 0.0254 cm (0.10 in)

slotted, PVC points.   The screens were positioned at 15.24 cm (6

in) intervals with the lower portion of the uppermost screen being

placed at the watertable, as shown in figure 3.2.

     During the summer of 1990 five more multilevel monitoring

wells were installed at this location. These wells were installed

in a transect perpendicular to groundwater flow with well "B" being

positioned 33.5 meters (110 ft) downgradient of well REC, with 3.05

M (10 ft) of separation between each of the five wells as shown in

figure 3.1.

      These wells were constructed based on a design by Bradbury and

 Bahr (1987). The wells consisted of a 1.91 cm (3/4 in) PVC spine

 which was screened over its last foot interval with a 30.48 cm (1

 ft) slotted point with 0.0254 cm openings. Surrounding the spine

 are up to 6, 0.635 cm inside diameter polypropylene tubes which

 were attached to the PVC center spine with nylon reinforced tape.

 The polypropylene tubes were perforated with 0.32 cm (1/8 in) holes

 and screened with TYPAR over the last 25.4 cm (10 in) section at

 the bottom of each tube. Each tube extends to a different depth in

 the aquifer to allow discrete samples to be taken from various
 depths as shown in figure 3.3.

      Four of the wells (A,C,D,E) have 5 sampling ports, including

 the spine, at 30.48 cm     (1 ft) intervals with the upper most


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