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ume, the acid-treated kaolinitic clay ncareous smectitic clay contained b '� P` ? rirM1i 'ersoirs input generated a dark red-color effluent that soil particles and a black ash-looking to smelled of acetic acid. The color was material, while effluent from mixed ca- P; A probably due to dissolution of iron tion illite contained red-tinted soil par- se" t Ll oxides which comprise �13% of the titles that became increasingly darker tar/ ;' solids in the kaolinitic clay soil The as more effluent was passed. Perme- acid-treated calcareous smectite began ability increases were probably due to Fluid passing cream-colored foamy effluent progressive soil t chambertt� after passage of -=28% pore volume. cleared initial cloggted pores.eventually Since the solid fraction of the smectite Due to the piping that occurred with To Sort q is X33% calcium carbonate,the largest the acid-treated soils,any fluid capable ,f gaaxoa portion of the creamy material was _of dissolving soil components cou po- sort , ,+ probably dissolved calcium, while the tentiall cause increases in permeabili- chamber �'-'`a foam was the result of CO2 liberation ty of clamsliners. It would seem that from the dissolved carbonates. 'neutralization of acids and bases prior Both noncalcarcous smectite and to their disposal would be the best safe- ; mixed cation illite permeated with ace- guard against clay liner failure unless 1 rr� tic acid eventually showed permeability the resulting salts have an adverse Outlet Porous atone g $ increases,but the increase did not occur effect on the liners. i�, P to Teflontubfrq,..J>1'vy !� Wasek,� ::.�:, until passage of 39%and 62%pore vol- Three of the four compacted clay q e em1tic®1-a m%-ea�permeator, ume respectively. Effluent from the soils permeated with acetone reached w` Four clay subsoils which had diverse mineralogical compositions and a range 1x10 ® " 19 of chemical and physical properties Clays typical of clay soils used to linedisposal F,. ,fib„4 °Noncalcareous smectitic i'facilities were selected. These clay sub- .Calcareous smectitic -soils, composed of predominantly ka o Mixed Cation kaolinitic olinitic, illitic or smectitic clay miner- ,MJ X10-1, %, als, were compacted according to •.,�! ;:,.{; $,. I •Mixed cation illitic 'ASTM standard D-698 and placed in etr permeameters modified for safe use �L�nt 'z C o with organic liquids (Figure I dj Permeability values were plotted I lxtp w'Aga : Inst cumulative pore volume of the 'Squid that passed through the com- ” rrr i?3,f� sed soils. Baseline permeability val- ' were established for each soil coreIt..A-;�,r:�r?i I I ,ettb water. These values are given tol�i,i)z1x10-�` e ~tie left of the dotted lines in Figures x>£lp1, b. I 28.2E.All four cls soils were found to Water I Acetic acid Acetone Y ( (0.01 N CaSOO (glacial) I (99%pure) istently qualify for lining h �$ waste landfills on the basis ofhw- s � �s..@ I (e) (b) I (c) permeabilities of less than x ]0� /sec. After establishing Basel' c 1x10-®; 0; '0.5 1:0 t`SR 2 pirmeabilities with water, the ater ; • 'fag I I r po° times either replaced by an organic liquid �t p+b. 9- "4( is the case of the control soil cores 2A), retained for the remain- •Nt^^a'1 ).f of the test. `a 1xt017 I I four clay soils permeated with . I ' acid showed initisl decreases in bility (Figure 2B). However, a x�•�X to I nt amount of soil piping oc- in these cores. The effluent was ,R =k1 x10! y tinted either red, creamy or indicating that soil components r1ti1 t>°•;h ®I I dissolved by the acid. Initial de- t � .;,;�., •I in permeability were thought to e 1 i to partial dissolution and subse- 1x10-® # migration of soil particles. Mi- ' . Methanol Xylene(99°i°pure i particle fragments could lodge lc (20%H,0) mixed isomers) St fluid conducting pores, thus t g permeability by reducing i', i(d) I (e) ,l t sectional area available for fluid 1x10 t4 1 09 ;J.5 2,0 0.0 t1'0.5 1 0 Y,1,5 t}2 0' Y the soils treated with acetic �`� r t � ". f ore.volumea t reous smectite and mixed Fig 2 Permeability of four compacted clay soils to a standard aqueous leachate contairang®,®1N kaolinite) showed continuous CIS', Vofume of permeant liquid was divided by volume of pore space in a soil to obtain the pore ty decreases throughout the volume value at which each permeability measurement was obtained. Venccal dashed lines indicate the A point at which the standard aqueous leachate was replaced by an organic liquid. Data points marked passage of ==20% pore vol- wilt)an asterisk are minimum values September 1952 Civil Engineering-ASCE 67