|
<br />9
<br />!ticroveQetative Stabilization
<br />Stabilization tests were initiated in which various microscopic plant
<br />forms such as algae, lichens, and mosses, rather than the macroscopic forms of
<br />vegetation, were evaluated as soil stabilizers. Lichen and moss crusts were
<br />collected from Canyonland National Park, Utah; from greasewood and sand dune
<br />areas near Delta, Utah; and from black sage and shadscale areas near Ely, Nev.
<br />these crusts were used to inoculate saline tailings from the Utah Copper Divi-
<br />sion of the Kennecott Copper Corp. A comparative control plot of nonsaline
<br />building sand was also inoculated. Preliminary investigations show relatively
<br />profuse growth on the control plots and virtually no growth on the Kennecott
<br />.tailings. Test plots on uranium, clay, and copper tailings, other than
<br />1(ennecott's, produced excellent cryptogamic plant growth, thus demonstrating
<br />that microscopic plant forms are as subject to salinity stress•as are the
<br />larger varieties of vegetation.
<br />Chemical-Veietative Procedure
<br />The Bureau-developed chemical-vegetative procedure involves the applica-
<br />tion of a small amount o£ chemicals to newly planted tailings to achieve sev-
<br />eral worthwhile goals. Sandblasting of plants is minimized. Moisture is
<br />retained in the tailings, Germination is promoted and wilting minimized by
<br />creating a dark heat-absorbing, nonreflecting surface on light-colored tail-
<br />ings. The result s.souglit from a chemical for use in the chemical-vegetative
<br />procedure differ markedly from those desired when achieving stabilization by
<br />chemicals alone, When stabilizing with chemicals only, the crust produced
<br />should be completely resistant to wind erosion, and either should be permeable
<br />enough to allow precipitation to be readily absorbed or conversely, be suffi-
<br />ciently resistant to water penetration to prevent erosion,. The wind-resistant
<br />crust produced by the chemical for the chemical-vegetative procedure should be
<br />(1) only sufficiently porous to permit slow penetration of moisture, which
<br />property also prevents to some extent the evaporation of water from the tail-
<br />ings, thus providing better moisture for plant growth; (2) permit air to pene-
<br />tra[e the tailings to produce proper air, water, and soil-plant relationship;
<br />and (3) be compatible with plant growth, a factor not required when chemically
<br />stabilizing only, Chemicals for both chemical and chemical-vegetative stabi-
<br />lizations should not degrade to produce water contaminants that may inhibit
<br />reuse of the tailing water.
<br />
<br />
<br />Several chemicals that were effective in forming wind-resistant crusts
<br />and could meet the projected requirements for compatibility with vegetative
<br />stabilization were selected for laboratory testing and evaluation. These
<br />included selected organic polymers, bituminous compounds, calcium and ammonium
<br />tignosulfonates, tall ofl fractions, wax and resin fractions, and resinous
<br />adhesives, Vegetative growth testing during the winter was accomplished in an
<br />indoor laboratory using Grow-lux lamps augmented with infrared lamps to more
<br />nearly approximate the sun`s rays, Summer testing was conducted outdoors
<br />under natural sunlight conditions. The results obtained from indoor testing
<br />, appeared to be compatible with those obtained under outdoor conditions..
<br />~;:.
<br />r~
<br />...~
<br />,~.
<br />-,~::
<br />.,.
<br />,I; ;
<br />I+ a i
<br />-~
<br />~:
<br />~. ' i
<br />+,.i ;
<br />~+ ; i
<br />...
<br />~' S.
<br />~~j",`.
<br />;; `~ ~
<br />~3~
<br />+I p, •: ,~
<br />_.
<br />', - ! `. i
<br />i.l
<br />. ~ t~
<br />~ :' ~ y
<br />~~
<br />i,
<br />{ ~
<br />' a
<br />.,
<br />. , .
<br />31. ~~ .
<br />ci.., ,
<br />` i i ! h
<br />.I. 1
<br />I
<br />.:
<br />I, i'i
<br />
|