PERMFILE66574

• Permit No: C1981016
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: Underground Disposal plans
• Section_Exhibit Name: APPENDIX A THRU C
• Media Type: D
• Archive: No

18
The present coarse refuse crusher is a~Jeffrey grate-type
hammermill powered by a 125 hp motor and producing mostly -1/4
in. material. This will have to be replaced by a crusher capable
of producing a 2 in. top size with minimal fines. Possible
candidates include:
a. Impact crusher
b. Roll crusher
c. Cone crusher.
The silica content (abrasive index), compressive strength,
flow rate and size consist of the coarse refuse will be the
determining factors in selecting an appropriate crusher.
The coarse refuse crusher is presently positioned in the
wash plant as illustrated in the elevation and section views of
Figure 4. The crusher is equipped with a discharge chute
(Item PL-36) for directing crushed solids into the thickener
sump (Item 27). Here the predominantly -1/4 in. crushed coarse
refuse can be mixed with thickener underflow and make-up water
to form a pumpable slurry. The wash plant, however, does not
have sufficient thickener underflow sump pumping capabilities or
pipeline size (ID) for slurry haulage of the crushed coarse •
refuse.
Presently this thickener sump receives thickener underflow
for pumping underground. Make-up water is occasionally added to
this sump when thickener underflow solids consistency becomes
high. The thickener underflow sump can be modified for coarse
slurry preparation. These modifications include:
a. Pumping thickener underflow directly underground, as
opposed to transferring it to the thickener underflow
sump first
b. Supply thickener underflow sump with an agitator
c. Supply thickener underflow sump with a bottom auger for
directing solids into the slurry pump inlet. -~
The coarse refuse slurry pumps can be placed next to the
thickener underflow sump (PL-27) as indicated by the dotted lines
in Figure 5.

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