1986-12-08_GENERAL DOCUMENTS - M1977493 ‎(2)‎

• Permit No: M1977493
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Date: 12/8/1986
• Doc Name: METHODS AND COSTS FOR STABILIZING FINE-SIZED MINERAL WASTES
• From: DEPARTMENT OF THE INTERIOR
• To: DRMS
• Media Type: D
• Archive: No

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other was sewage sludge. Both are bulky organic materials which, when mixed
with tails, yield soillike textures and mineral, air, and water relationships.
Plots prepared with Kennecott Copper tailings and 5 to 15 tons per acre of
each of the two waste-derived products indicated the additives to be benefi-
cial to both vegetative germination and growth. The sewage sludge produced '
growth than the commercial compost, and plots treated with either mate-
better 8
rial demonstrated much better growth when additional fertilizer was added.
Buried Organic Layers n
As noted, one of the difficulties in growing plants on tailings is the
matter and accompanying microbial populations. Results of
lack of organic ;,o
initial tests made by mixing the equivalent of 5 to 15 tons per acre of sludge
or compost into the surface 3 inches of tailings were encouraging. Subse-
quently, tests were made on the use of tailings pelletized with sewage sludge
o form a surface layer and on the effect of buried layers of sewage sludge on
the pH and salinity of the tailings being tested.
A series of tests was made in which 2-inch layers of sewage sludge were
placed at different depths in barrels containing an 18-inch depth of Kennecott
tailings. Sludge was placed at depths of 3, 7, 11, and 15 inches below the {
i E
surface of the tailings. In another test series, the layering pattern was
unchanged but an additional equivalent of 15 tons per acre of sewage sludge
was mixed into the top 3 inches of tailings. Crested wheatgrass , Ranger
alfalfa, and rye grain seeds were planted for both series of tests with barley
used as the fourth seed in one test series , and a small transplanted tomato 4
was used as the fourthp Y plant variety in the other series of tests. Table 2
shows the number of plants germinating per 100 seeds 2 weeks after planting
and the number surviving at the end of 10 weeks. y
TABLE 2. - Germination and survival of four species of plantsi j
with 2-inch sludge layers at various depthsi,', .,
Depth of Number of plantsl '''!'
sludge layer Crested wheat rass Ran er alfalfa R e rain Barle grain
below surface, Germi- Sur- Germi- Sur- Germi- Sur- Germi- Sur- f' I,
i inches nation vival nation vival nation vival nation J vival
SERIES 1 NO SLUDGE ADMIXED INTO TOP 3 INCHES OF TAILINGS
3 71 4 70 8 83 23 89 0
7 88 37 78 4 92 39 97 21
�i
11 73 42 81 9 89 43 94 14
15 53 28 59 6 83 28 95 2
SERIES lA 15 TONS PER ACRE SEWAGE SLUDGE IN TOP 3 INCHES OF TAILINGS
3 90 26 36 5 74 64 ( ) ( ) i
7 80 24 41 4 71 56 (2 ) (2)(2 )
11 78 15 59 1 78 53 (2) (2)
15 77 56 67 19 80 60 i
'Germination rate at 2 weeks after planting and survival of plants after
i
10-week growth.
`Tomato plants approximately 2 inches high were planted in the fourth quadrant
of the barrels.