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Freezing and drying: effects on the solubility of municipal wate constituents

Item Type text; Thesis-Reproduction (electronic)

Authors Bitterli, Ronda Jo

Publisher The University of Arizona.

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Link to Item http://hdl.handle.net/10150/557690 FREEZING AND DRYING: EFFECTS ON THE SOLUBILITY OF MUNICIPAL

SOLID WASTE LEACHATE CONSTITUENTS

by

• - Ronda Jo Bitterli

A Thesis Submitted to the Faculty of the

DEPARTMENT QF SOILS, WATER AND ENGINEERING In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE WITH A MAJOR IN SOIL AND WATER SCIENCE In the Graduate College

THE UNIVERSITY OF ARIZONA

19 8 1 STATEMENT BY AUTHOR

This thesis has been submitted in partial fulfill­ ment of requirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowl­ edgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judgment the proposed use of the material is in the inter­ ests of scholarship. In all other instances, however, permission must be obtained from the author.

SIGNED: ^

APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below: jf&ticxce 3°i WALLACE H. FULLER V Date Professor of Soils, Water and ' Engineering ACKNOWLEDGMENT

I'd like to take this opportunity to acknowledge the professors on my graduate committee. The comments and sug­ gestions I received from Dr. Post, Dr. Warrick, and.Dr.

Fuller greatly aided me in the completion of my thesis. Dr. Gardner's presence at my oral examination was also greatly appreciated. I'd also like to recognize my colleagues. The assistance and friendship of Dr. Elvia Niebla, George Carter, Marvin Unger, Dr. Juan Artiola, Jim Budzinski, Mike Boyle, Dr. Aziz Amoozegar-Fard, and Glynis Coulter helped me through the hard times and made the good times even better. Finally, I'd like to extend special appreciation to my major professor. Dr. Wallace H. Fuller. The time he has devoted to me and his patience and personal attention have gone beyond the call of duty and have helped to make my stay at The University-of Arizona especially meaningful and re­ warding. TABLE OF CONTENTS

' Page

LIST OF TABLES ...... V

LIST OF ILLUSTRATIONS ...... vi

ABSTRACT ...... vii

INTRODUCTION . ... 1

MATERIALS ...... 4 METHODS...... 9 Freezing-Thawing ...... 9 Wetting-Drying ...... 10 Chemical Analyses ...... 11 Statistical Analyses for Wetting-Drying ...... ' 12 Statistical Analysis for Freezing-Thawing .... 12 RESULTS ...... 14 Wetting-Drying...... <•..... 14 Freezing-Thawing ...... 18 DISCUSSION ...... 23 SUMMARY . . 26

APPENDIX A. COLLECTED D A T A ...... 28

LIST OF REFERENCES ...... 35

iv LIST OF TABLES

Table ■ Page

1. Partitioning of Materials in the Municipal i Waste-Type Landfills Used, in Generating I, IT, and III (Fuller, 1978) , . . 5

2. Some Chemical Characteristics of Natural Leachates I, II, and III . . . & ...... 6

3. Some Chemical Characteristics of Zn- and Cd-enriched Leachate III ...... 7 4. Extent of Solubilization of Constituents After Rewetting the Dried Residues ...... 15

5. Total Organic Carbon Remaining Soluble After Freezing for Natural Leachates I, II, and III ...... 19

6. Levels of Constituents in Solution After Freezing for Enriched Leachate III ...... 20

•7. pH and Constituent Levels for Natural Leachates I, II, and ill After Drying .... 29

8. pH and Constituent Levels for Enriched Leachate III After Drying ,....'...... 30 9. pH and Total Organic Carbon Levels for Natural Leachate I After Freezing ...... 31

10. pH and Total Organic Carbon Levels for Natural Leachate II After Freezing ...... 32 11. pH and Total Organic Carbon Levels for Natural Leachate III After Freezing ...... 33

12. pH and Constituent Levels for Enriched . Leachate III After Freezing ...... 34

v LIST OF ILLUSTRATIONS

Figure Page

1. The effect of air drying and rewetting on .thexsolubility of total organic carbon. Mg, Ca or Cd, Zn, and Fe of three municipal solid waste leachates ...... 16 2. The influence of drying and of repeated freezing and thawing on the solubility of the total organic carbon constituents of three municipal solid wasteleachates .... 17 3. The influence of repeated freezing and thawing on the solubility of total organic carbon, Fe, Zn, and Cd of Zn- and Cd-enriched Leachate III ...... 21

vi ABSTRACT

Laboratory studies were conducted to evaluate the effects of freezing-thawing and wetting-drying on concentra­ tions -of potentially hazardous constituents contained in municipal solid waste leachates. Drying and freezing are both naturally occurring processes that affect the solubility of leachate constituents. After periods of rainfall, precipitates form as the water evaporates, Our results indicate that upon rewetting, the constituents only partially go back into solution. This is desirable from the standpoint of preventing the contamination of underground water supplies— the more constituent that precipitates out and remains insoluble, the less that is available to migrate through the soil. Freezing, important in cold regions, is also a dehydration process involving the separation of the aqueous and solid phases. Water freezes initially with the remain­ ing highly impure solution freezing at a lower temperature. Our results indicate that upon thawing only part of the constituent reenters the aqueous phase with constituent concentrations continuing to decrease with successive freeze-thaw cycles. Like drying, then, freezing effectively reduces the amount of constituent available to migrate through the soil.

vii INTRODUCTION

Constituents contained in wastes deposited on land are solubilized by rainwater and move through the soil. Contamination of underground water supplies is inevitable unless the movement of the hazardous constituents is con­ trolled. Previous work has shown that movement of constitu­ ent is affected by the nature of the constituent, the type of solution in which it is carried, and the soil through which it moves (Fuller et al., 1976). Naturally occurring processes also have an effect on constituent mobility. In dry periods, for example, the water evaporates and the solutes precipitate. Upon rewetting, it was ob­ served that only part of the constituent may go back into solution and become available again to move. Freezing, another dehydration process, has long been recognized as a method of desalinating water (Stinson, 1976). Heller (.1939) , Geller (1962) , Szekely (1964), and Stinson (1976) each used atmospheric freezing of brackish water as a means of separating water from the dissolved . Ice of a higher purity is first formed leaving a solution high in salt content. When complete freezing occurs, precipitates develop ("Harvesting the Glauber," 1955? Stinson, 1976) . Although much research concerning the desalination of water by natural atmospheric freezing has been conducted, the major interest has been in purifying the water rather than in im^ mobilizing potential polluting constituents. However, the same principles should apply: ■ in effect, atmospheric freezing of municipal solid waste.(MSW) leachate solutions causes a separation of water and the soluble leachate con­ stituents which form precipitates upon complete freezing. Work conducted by Forsyth and Fraser (1947) on the freezing of gels has shown that the coagulation that is caused is sometimes irreversible. Their study of organic colloids showed that freezing to a temperature ...of at least -3°C and then thawing destroyed the colloidal properties and allowed the solid and aqueous phases to separate, In this way, a single freezing and thawing reduced the moisture con­ tent of a humus preparation to one-thirtieth of the original

Solid waste landfill leachates are abundantly supplied with colloids, including humic and fulvic acids (Artiola-Fortuny, 1980)_. Therefore, the same processes could be expected to apply to freezing and thawing of MSW leachates. Freezing and thawing, for example, may destroy certain colloidal properties and allow for a greater separation of the differ­ ent phases thereby increasing the rate of precipitation. Additional freeze-thaw cycles could have a continued puri­ fying effect.

Research was conducted, therefore, to determine the effects of freezing-thawing and wetting—drying on the con­ centrations of Fe, Zn, Cd, Ca, Mg, Na, K, and TOC and on pH since pH of the leachate affects the solubility of most constituents. MATERIALS

Four -thousand-liter capacity tanks containing typical municipal solid wastes (Table 1) were used in generating the three leachates used in this study. The composition of these leachates has been monitored through monthly chemical analyses since establishment of the tanks; Tables 2 and 3 list some of the chemical characteristics of the three leachates. Leachate I, the oldest of the leachates

(5.5 years), originated in a concrete septic tank coated on the inside with epoxy sealant. Leachates II and III (3.5 and 0.5 years, respectively) originated in steel tanks also sealed with epoxy. Unenriched ("natural") leachates I, II, and III and Zn- and Cd-enriched Leachate III were used. Leachate III was enriched by adding CdCl^ and ZnC^ to give a concentration of approximately 112 mg/1 Cd and 65 mg/1 Zn or a concentration of 0.001 M of each element. As a leachate ages, the pH rises while TOC and other contaminant levels decrease (Fuller, 1980). Thus, the three leachates used in this study provided a range of conditions under which to study the effects of freezing-thawing and wetting-drying. Natural Leachate III, for example, is the youngest of the leachates. pH for this leachate at the beginning of the study was 4,9; pH for natural Leachate I, the oldest of the leachates, was near neutral (6.7). Also, 5

Table 1. Partitioning of Materials in the Municipal- Waste- Type Landfills Used in Generating Leachates I, II, and III (Fuller, 1978)

Amount Loaded in 4000-1 Generator Solid Waste Material --- :—;--- — kg %

Paper (mostly newspaper) 6-36 45.7 Food waste 204 14.7 Garden waste 171 12.3 Plastic 15 1 Rubber „ - 50 10.2 Leather 27 Textiles 50 Metal (mostly cans) 85 6.1 Glass 8 0 5.8 Ash •. 4.1 Soil s II > Calf Manure 16 1.1 Table 2. Some Chemical Characteristics of Natural Leachates 1, II, and III'

Leachate Age PH EC TOC Ca Mg '• Na K ' Fe Zn Cd mmhos/ yrs cm -mg/L--

Leachate I 5. 5 6. 68 4.7 364 167 68.2 92.9 547 44.8 0.52 <0.02

Leachate II 3.5 6.84 6.0 552 126 49.2 99.9 434 37.1 0.85 <0.02

Leachate III 0.5 4.93 13.0 8220 751 211 329 1240 1180 6.19 <0.02 7 Table 3. Some Chemical Characteristics of Zn- and Cd- enriched Leachate III

Replication pH EC TOC Fe Zn . Cd

mmhos/cm ------mg/1------

Rep 1 5.3 9.8 8400 1200 61.3 116

Rep 2 5.3 9.9 8190 1170 62.4 117

Rep 3 5.3 • 10.1 8090 1190 60.8 117

Rep .4 5.3 10.1 8190 1170 62.4 119

Avg 5.3 10.0 8220 1180 61.7 117 SD 0 0.2 130 15 0.8 1 TOC,. Ca, Mg, Na, K, F e , Zn, and Cd levels were all higher for natural Leachate III than they were for the older leachate.

Leachate III was studied in both an unenriched and an enriched state. This was done for two reasons. First, the addition of Zn and Cd to the leachate brought up levels of these elements to levels that could be detected by our instrumentation. Also, enrichment of the leachate with Zn and Cd might provide a reasonable approximation of the composition of a MSW leachate that had somehow been con­ taminated or enriched from- additions of industrial wastes. METHODS

Since even brief exposure to the air has been shown to cause both precipitation and an increase in pH (Fuller,

1978), carboys of each leachate were collected from the leachate generators under an atmosphere of COg to keep the "leachates from being exposed to the air. One carboy was collected for each of the natural leachates and for en­ riched Leachate III. CO2 was bubbled slowly through the solution in each carboy for several days in order for stabilization to take place. Clear samples were then drawn from the bottom of the containers.

. _ ... . Freezing-Thawing

For each leachate, five freeze-thaw cycles were con­ ducted, Samples for each freeze were replicated four times giving a.total of 20 samples for each leachate. These samples were placed in a freezer at -24.5°C where they re­ mained until completely frozen (overnight). All of the samples were then removed from the freezer and were allowed to thaw at room temperature for 24 hours. This constituted the first freeze-thaw cycle. At this time, all of the samples except the.four designated for the first freeze-thaw. cycle were placed back into the freezer to begin the second cycle. The four samples that had been set aside for 10 analysis were centrifuged for 30 minutes at 5000 rpm then filtered using a Sartorius Membrane Filter fitted with a

0.45 |j,m filter to separate the soluble from the insoluble constituents as defined by the U. S.Environmental Protection Agency (1971). The filtrates were analyzed for Cd, Zn, and

Fe, and the pH and TOC levels were determined.

The samples' that had been placed back, into the. freezer were removed when frozen and again were allowed to thaw for 24 hours. This constituted the second freeze-thaw cycle.

All but four of the samples were placed back into the freezer; the four samples not frozen were centrifuged, fil­ tered, then analyzed. This process continued until five cycles were completed, at which time only four samples re­ mained to be analyzed. Analysis Of these four samples com­ pleted the freeze-thaw experiment.

Wetting-Drying Four 100-ml replications for each tank were placed in the bottom of truncated polyethylene bottles. Only one wetting^drying cycle was conducted, so for each leachate there was a total of only four samples. These were allowed to air dry at room temperature with a fan blowing across the exposed surfaces to aid in . Complete evapora­ tion occurred within a couple Of days. Drying to constant weight was completed in a •lyophilizer. The residues in the bottom of the truncated bottles represented the constituents present in the 100 ml of the original leachate sample.

Therefore, it was necessary to bring the residues back up to

the 100-ml volume so that the analyses performed on the wetted samples could be compared to original values. For this reason, 100 ml of deionized water was added to each of

the residues which then stood at room temperature for 24 hours in order for the residue to approach equilibrium with the solution. During this period, some evaporation had occurred, so the samples were again brought up to volume in a IQQ-ml volumetric flask. The samples were passed through

a Sartorius Membrane Filter apparatus fitted with a 0.45 pm filter. The filtrates were analyzed for Ca, Mg, Na, K, F e ,

Zn, and Cd and the pH and TOC levels were determined.

Chemical Analyses

The glass electrode was used in measuring all pH values; EC measurements were made according to recommenda- _ tions by the United;.States-Department of -Agriculture (1954) in Agriculture Handbook No. 60; TOC levels were determined using the Beckman Model 315A Total Organic Carbon Analyzer. Elemental concentrations were determined by either atomic absorption or flame emission spectroscopy on the Jarrell- Ash 810 Atomic Absorption Spectrophotometer in accordance with;.the procedures recommended by the U. S. Environmental Protection Agency (1979) . Statistical Analyses for Wetting-Drying

For Zn- and Cd-enriched Leachate III, each con­ stituent level after drying (an average of four replications) was compared to an original value (also an average of four replications). A one-sided t—test for the difference be­ tween two means was used in determining whether there was a. significant decrease in constituent levels after drying. However, for natural leachates. I,. II, and III each con­ stituent level after drying (an average of four replications) was compared to a single original value. In this case, it was necessary to use a special case of the t-test since only one mean and one'sample variance could be determined.

The t-tests for the difference between two means and for comparison of the mean of a sample to a single observa­ tion are outlined by Sokal and Rohlf (1969).

Statistical Analysis for Freezing-Thawing The "least significant difference" method was used in determining whether significant reductions in a constituent level occurred with successive freezing-thawing. The data were processed by computer using the SPSS program developed at Northwestern University (Nie et al., 1975), The results are represented by lines which connect means that have been determined not to be different from each other; two -means that are not connected by a line are statistically different. 13

All comparisons were made at both the 0.05 and 0.01 levels of significance. Significance at the 0.05 level indicates 95%- certainty that the treatment was responsible for the differences observed between the two values. Similarly, significance at the 0.01 level indicates 99% certainty that the treatment was responsible for the observed differences. RESULTS

Wetting-Drying The results of the wetting-drying experiment are presented in Table 4 in terms of percentage of the original level of constituent solubilized upon rewetting the dried residues. These results are presented graphically in Figures

1 and 2. The data, averages, and standard deviations are presented in Tables 7 and 8 (Appendix A).

For the older leachates (I and II) levels of Na and

K did not change upon drying and rewetting. As univalent cations, Na and K would be expected to be more soluble than polyvalent cations such as Ca, Zn, and Fe. Consequently, upon rewetting, precipitates of Na and K formed upon drying would be expected to go back into solution more completely than precipitates formed with higher valenced cations. This mechanism possibly explains the observation that levels of Na and K in the older leachates did not change upon drying and rewetting.

Levels of Na and K in the youngest leachate (III), however, did decrease significantly upon drying and re­ wetting. As the youngest leachate. Leachate III contains higher levels of both Na and K. Precipitation is more likely to occur with the higher concentrations with less goinq back into solution upon rewetting,

14 Table 4. Extent of Solubilization of Constituents After Revetting the Dried Residues

Leachate PH TOC Mg Ca Cd Zn Fe . " Na K

Q. f /original ~ \ V* 1 ZT I y^\ ol e .

Leachate I 9.6 66.2* 71.4 11.1** nd 2.0** 0.02** 100 95.0

Leachate II 9.4 52.2** 55.9* 16.7* nd 4.3** 0.66** 100 86.9

Leachate III 5.4 62.7** 67.3** 97.1 nd 51.7**r 0.01** 81.8** 91.9** Enriched Leachate III 5.5 56.4** nd nd 74.5** 81.7** 0.5** nd nd

*Significant at the 5 per cent level.

**Significant at the 1 per cent level, nd = not determined. ENRICHED I— LEACHATE I LEACHATE H LEACHATE H LEACHATE H . z z 100- UJ o II 80- CO o oZ CO 60- u z

40 -

_ ^ 20)—

t = V C7» O C ,0) C7> O C ,0) U o c ,

Figure 1. The effect of air drying and rewetting on the solubility of total organic carbon, Mg, Ca or Cd, Zn, and Fe of three municipal solid waste leachates.

or Figure ORIGINAL TOTAL ORGANIC CARBON REMAINING IN SOLUTION - % 2 100- . 80 — 60- 40- 40- 0 2 - h ifune f rig n f eetd reig n taig n the on thawing and freezing repeated of and drying of influence The oi at leachates. waste solid solubility of the total organic carbon constituents of three municipal municipal three of constituents carbon organic total the of solubility ' 5 4 3 I 2 LEACHATE I < ------LEACHATE 3 5 4 3 2 FREEZES - JL LEACHATE HI 3 5 4 32 LEACHATE ENRICHED 3 5 4 3 2 JJL [-DRYING-I M w H UJ UJ LU LU p LU LU UJ UJ J J d {Tj Ld W UJ UJ < z < < < J J J cl c l _ _J _J _J l l p I

18

Upon drying, Fe and Zn levels for all the leachates decreased significantly at the 0.01 level. Cadmium levels, determined only for enriched Leachate III, also decreased significantly (0.01). Magnesium and Ca were removed from solution in varying degrees depending on the leachate. TOC levels also decreased significantly for each of the leachates studied. However, statistical t-tests showed that TOC levels for natural leachates II and III and enriched Leachate III decreased at the 0.01 level of significance while the oldest leachate showed a decrease only at the 0.05 level of significance.

Freezing-Thawing

The results of the freezing-thawing experiment are presented in Tables 5 and 6 in terms of percentage of the original level of constituent remaining in solution after successive freeze-thaw cycles. These results are presented graphically in Figures 2 and 3. The data, averages, and standard deviations are presented in Tables 9-12 (Appendix A) . For enriched Leachate III, Fe and Cd concentrations decreased significantly at the 0.01 level after one freeze- thaw cycle. Only for Fe was there any further decrease with

. - additional^cycles. Zinc levels decreased significantly (0.01) from the original level after two freezes. 19

Table 5- Total Organic Carbon Remaining Soluble After Freezing for Natural Leachates I, II, and III

Leachate ~ pH % of original

Leachate I: Original 6.7 100.0* Freeze I 8.0 73. 6 - Freeze IT ... 8.0 62.6 Freeze III ' 8.1 60.7 i Freeze IV 8.0 31.3 Freeze V 8.1° 31.3 H Leachate H Original 6.8 100.0 Freeze i 8.0 56.3) Freeze ii 8.0 54.7 Freeze m 8.1 55.6 Freeze IV 8.2 36.2 | Freeze V 8.4 38.0 1

Leachate III: Original 4.9 100.0 Freeze I 5.2 90.5 Freeze II 5.2 90.1 Freeze III ■■■■ 5.1 91.8 Freeze IV 5.1 ’ 85.9 Freeze V 5.1 84.1

*The. least significant difference method was used at the 1 per cent level of significance. 20

Table 6. Levels of Constituents in Solution After Freezing for Enriched Leachate III

Freeze PH TOC Fe Zn Cd — % of original-''

Original 5.3 100.0 ■* 100.0 100.0 100.0 .1 5.4 95.9 83.0 96.6 84.9

II 5.3 93.4 78. 8 92.7 84.4 III 5.3 92.2 63.8 89.3 81.7

IV 5.3 91.6 64.0 87.7 81.4

V 5.3 89.5 52.0 79.8

*The -least significant difference method was used at the 1 per cent level of significance. Figure 3. The influence of repeated freezing and thawing on the solubility of solubility the on thawing and freezing repeated of influence The 3. Figure ORIGINAL CONSTITUENT REMAINING IN SOLUTION- 100 60 40 80 20 oa ognc carbon organic total 2

TOC 3

4

5 , Fe f Zn, and Cd of Zn- and Cd-enriched Leachate Cd-enriched and Zn- of Cd and f Zn, Fe 2

Fe 3

4

5 FREEZES 2

Zn 3

4 r3 ^ Cd

4

5 22

Only for the natural leachates did TOC levels sig­ nificantly drop after one cycle with very little or no change occurring throughout the rest of the experiment. TOC levels for enriched Leachate III changed very little throughout the course of the experiment. DISCUSSION

For the elements studied in these experiments, an

increase in pH would lessen contaminant solubility (Fuller,

1977). In both wetting-drying and freezing-thawing, pH for the older leachates increased from near neutral to basic-

Therefore, it appears that drying and freezing of the older leachates produces favorable conditions for immobilization

of contaminants through precipitation. The data in Table 4

show that, with the exception of Na and K, constituent levels in the older leachates did decrease significantly after drying. In freezing, the increase in pH occurs only initially with very little change in pH occurring with successive freezing-thawing. Additional cycles, then, would remove little additional constituent from solution due to pH effects alone.

In addition to pH, organic carbon constituents also haye an influence on" heavy metal migration through soils due to their ability to form insoluble precipitates with some contaminants (Fuller, 1977). Chelation, however, may

complicate precipitation by forming soluble compounds with

the trace contaminants. It appears that chelation may have played a greater role in the freezing-thawing process than in wetting-drying since wetting-drying accomplished ,a 24

greater removal of constituents from solution than did

freezing-thawing. Overall, air drying is much more effective than freezing in lowering the concentration of leachate consti­

tuents in solution. A possible explanation for this is that

drying accomplishes a much more complete dehydration than

freezing. This would eliminate problems caused by complex

formation with trace contaminants. Furthermore, it is known that in freezing, ions are selectively incorporated into the ice phase (Gross, 1968). This selective ion incorporation accounts not only for the variability in the rate of removal

of different constituents from the leachate solution (Malo

and Baker, 1968) but also for the lesser extent to which precipitation (and therefore immobilization) occurs upon freezing as opposed to drying.

It should be noted that this research was conducted on leachates that were independent of a solid phase. Con­

sequently, these results cannot directly be applied to MSW leachates in contact with the soil. When soil is involved, freezing and drying effects in relation to possible inter­ actions of the leachate with the soil will have to be con­ sidered.

Finally, these results have important implications concerning sample handling in any research program. Freezing samples in order to preserve them for future analyses may change the solutions by removing constituents through 25 precipitation. Adding acid to the solutions to resolubilize the constituents may not be sufficient for 100% recovery.

Similarly, any procedures involving the dehydration of samples may alter the properties of those samples. For example, oven-drying or even air-drying a soil sample prior to the determination of any physical property may result in concentration of the clay which, in turn, alters the physical properties of that soil. Reevaluation of methods . of sample handling may be indicated. , SUMMARY

The results indicate that a highly significant re­

duction in the concentration of certain constituents con­

tained in leachate solutions occurs with one air drying. This suggests that drying can contribute to the control of

pollutant migration through the soil. However, further studies will have to be conducted to determine the extent to which the constituents remain insoluble with additional

wetting-drying cycles. Freezing is another naturally occurring process that

can also contribute to the control of pollutant migration.

One freeze-thaw cycle can remove constituents from the leachate solution with a continued removal occurring with additional cycles. Therefore, in suitable locations,

natural freezing-thawing may work to advantage in decreasing constituent levels in leachate solutions. Like drying, then, freezing can decrease the potential for pollutant migration. In addition to decreasing the rate of migration of potentially hazardous constituents contained in aqueous leachate solutions, dehydration through freezing or drying has important implications in methods of sample handling. Any procedures involving the freezing or drying of solutions or soils, for example, may result in an alteration of the

26 chemical or physical properties of those samples. The results of this research indicate that methods of sample handling may need to be reevaluated. APPENDIX A

COLLECTED DATA

28 Table 7. pH and Constituent Levels for Natural Leachates I, II, and III After Drying

Leachate pH TOC Ca Mg Fe Zn Na K

Leachate I; Rep 1 9.5 218 15.2 44.9 0.0121 91.2 492 Rep 2 9.6 215 25.4 35.6 0.00766 0.0121 103 ’484 Rep 3 9.6 281 69.3 0.00766 0.0075 123 525 Rep 4 9.6 250 15.2 44.9 0.0168 99.9 509 Avg 9.6 241 18.6 48.7 0.0107 0.0106 104 503 SD 0.05 31 5.9 14.4 0.0053 0.0027 13.4 18. 3 Leachate II: Rep 1 9.4 282 25.4 22.6 0.327 0.0336 112 372 Rep 2 Rep 3 9.3 282 16.7 29.9 0.280 0.0374 112 398 Rep 4 9.5 301 29.9 0.131 0.0392 99.9 362 Avg 9.4 288 21.1 27.5 0.246 0.0367 108 377 SD 0.1 11.0 6.2 4.2 0.102 0.0029 7.0 18. 6 Leachate III: Rep 1 5.4 5090 764 141 8.2 3.2 264. 1130 Rep 2 5.4 5140 820 143 12.7 3.1 272 Rep 3 5.4 5140 679 140 12.7 3.1 269 1140 Rep 4 5.4 5240 651 143 12.7 3.2 269 1140 Avg 5.4 5150 729 142 11.6 3.2 269 1140 SD 0 62.9 77.7 1.5 2. 3 0.06 3.3 5. 8 30

Table 8. pH and Constituent Levels for Enriched Leachate III After Drying

Enriched Leachate III pH TOC Fe Zn Cd

•ing/1

Rep 1 5.5 4530 5. 5 49.2 82.2 Rep 2 5.5 4400 3.9 48.1 86.8

Rep 3 5.4 4850 7.0 51.7 90.5

Rep 4 5.5 4760 7.0 52.4 89.4

Avg 5.5 4640 5.9 50.4 87.2 SD 0. 05 207 1.5 2.0 3.7 31

Table 9. pH and Total Organic Carbon Levels for Natural Leachate I After Freezing

Freeze pH TOC mg/1 Freeze I: Rep 1 8.0 208 Rep 2 223 Rep 3 8.0 379 Rep 4 8.0 260 Avg 8.0 268 SD 0 77.5 Freeze II: Rep 1 8.0 247 Rep 2 8.0 240 Rep 3 . 8.1 196 Rep 4 7.8 230 Avg • 8.0 228 SD 0.13 22.6 Freeze III: Rep 1 8.2 207 Rep 2 8.3 206 Rep 3 8.1 253 Rep 4 7.9 219 Avg 8.1 K 221 SD ’ 0.17 22.0 Freeze IV: Rep 1 00 i—1 114 Rep 2 Rep 3 7.8 Rep 4 8.2 113 Avg 8.0 114 SD 0.21 0.7 Freeze V: Rep 1 8.1 114 Rep 2 8.2 112 Rep 3 8.0 116 Rep 4 8.1 Avg 8.1 114 SD 0.08 2 . 0 32

Table 10. pH and Total Organic Carbon Levels for Natural Leachate XL After Freezing

Freeze pH TOC

mg/1 Freeze I: Rep 1 7.9 314 ' Rep 2 8.3 ' 306 Rep 3 7.9 338 Rep 4 8.0 287 . Avg 8.0 311 SD 0.19 21.1 Freeze II: Rep 1 8.0 282 Rep 2 8.0 383 Rep 3 7.9 270 Rep 4 8.0 271 Avg 8.0 302 SD 0.05 54.6 Freeze III: Rep 1 8.2 . 298 Rep 2 8.3 311 Rep 3 7.8 311 Rep 4 8.0 Avg 8.1 307 SD 0.2 7.5 Freeze IV: Rep 1 8.2 183 Rep 2 8.1 214 Rep 3 8.2 182 Rep 4 8.5 220 Avg 8.2 200 SD 0.17 20.1 Freeze V: Rep 1 8.1 221 Rep 2 8.5 180 Rep 3 8.7 200 Rep 4 8.3 238 Avg 8.4 210 SD 0.26 25.2 33

Table 11. pH and. Total Organic Carbon Levels for Natural Leachate 1:11 After Freezing

Freeze PH TOC mg/1 Freeze I: Rep 1 5.2 . 7500 Rep 2 5.2 7100 Rep 3 5.3 7730 v.. Rep 4 Avg 5. 2 7440 SD 0.06 319 Freeze II: 'Rep 1 " 5.2 6900 Rep 2 5.2 7480 Rep 3 5.2 7780 Rep 4 5.2 7480 Avg 5.2 7410 SD 0 368

Freeze III - R e p ' 1 5.1 7860 Rep 2 5.1 7150 Rep 3 5.1 7880 Rep 4 5.1 7310 Avg 5.1 7550 SD 0 375 Freeze IV: Rep 1 5.1 6560 Rep 2 5.1 6770 Rep 3 5.1 7150 Rep 4 5.1 7770 Avg 5.1 7060 SD 0 531 Freeze V: Rep 1 5.1 6900 Rep 2 5.1 Rep 3 5.1 7300 Rep 4 5.1 6530 Avg 5.1 6910 SD 0 385 34

Table 12. pH and Constituent Levels for Enriched Leachate III After Freezing

Freeze pH TOC Fe Zn Cd -mg/l- Freeze I: Rep 1 5.3 8090 971 59.4 98.8 Rep 2 5.4 986- 59.4 99.5 Rep 3 5.4 7670 986 60.2 100 Rep 4 5.4 7880 ' 971 59.4 98.8 Avg 5.4 7880 979 59,6 99.3 SD. 0.05 210 . 8,7 0.4 0.6 Freeze II: Rep 1 5. 3 7480 893 56.2 97. 6 Rep 2 5.3 7780 974 58.5 Rep 3 5.3 962 57.8 100" Rep 4 5. 3 7780 893 56 . 2 9 8.9 Avg 5.3 7680 930 57.2 98.8 SD 0 173 43.6 1.2 1.2 Freeze III: Rep 1 5.3 743 55.9 98.4 Rep 2 5.3 806 53.9 93.6 Rep 3 5.3 • 7470 735 57.2 100 Rep 4 5.3 7690 727 53.2 90.2 .Avg 5.-3 7580 753 55.1 95.6 SD 0 156 36.1 1. 8 4.5 Freeze IV: Rep 1 5.3 7500 781 53.7 94.0 Rep 2 5.3 7690 54.5 96.0 Rep 3 5.3 54.1 98.0 Rep 4 5.3 7410 729 93.0 Avg 5.3 7530 755 54.1 95.2 SD 0 143 36. 8 0.4 2.2 Freeze V: Rep 1 5.3 7360 656 99.5 Rep 2 5.3 7460 642 57.7 90.0 Rep 3 5.3 7410 543 56.9 90.0 Rep 4 5.2 7210 56.2 94.2 Avg 5.3 7360 614 56.9 93.4 SD 0.05 108 61.6 0. 8 4.5 LIST OF REFERENCES

Artiola-Fortuny, J. 1980. Concentration of phenols in waste waters and their adsorption by soils. Ph.D. thesis, Univ. of Ariz.z Tucson. Forsyth, S. G. C .t and G. K. Fraser. 1947. Freezing as an aid in the drying and purification of humus and allied materials. Nature 160:607. Fuller, W. H. 1977. Movement of selected metals, asbestos, _ and cyanide in soil: Application.to waste disposal problems. EPA-600/2-77-020, U. S. Environmental Protection Agency, Cincinnati. Fuller, W. H. 197 8.Investigation of landfill leachate pollutant attenuation by soils. EPA-600/2-78-158. U. S. Environmental Protection Agency, Cincinnati. Fuller, W. H. 198 0. Soil modification to minimize movement of pollutants from solid waste operation. Critical Rev. Environ. Contr. 9(3):213-270. CRC Press, Inc., Boca Raton, Florida. Fuller, W. H ., Colleen McCarthy,. B. A. Alesii, and Elvia Niebla. 1976. Liners for disposal sites to retard migration of pollutants. pp. 112-12 6. In W. H. Fuller (ed.), Residual management by land disposal. EPA-600/9-76-015. U. S. Environmental Protection Agency, Cincinnati. Geller, S. Yu. 1962. Desalting of water by natural ■ freezing for farm use. From Izvestiya Akademii Nauk USSR, seriya geograficheskaya, No, 5, pp. 71- 77. .

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Heller, S. J. 1939. New method to obtain fresh water in the desert. Problems of Physical Geography No. VII USSR, Trans, by R. Heinze, Saskatchewan Research Council. Malo, B. A., and R. A. Baker. 1968. Cationic concentra­ tion by freezing. pp. 149-163. In Robert F. Gould (ed.), Trace inorganics in water. American Chemical Society, Washington, D. C. Nie, Norman H., C. Hadlai Hull, Jean G. Jenkins, Karin Steinbrenner, and Dale H. Bent. 1975. Statistical Package for the Social Sciences. McGraw-Hill, New York.

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Stinson, Donald L. 1976. Atmospheric freezing for water desalinization. pp. 112-118. In Gary F. Bennett (ed.). Water— 1976: I. Physical, chemical wastewater treatment. AIChE Symposium Series, No. 166, Vol. 73. Szekely, T. 19 64. Water purification by freezing in dug- outs. Work done during the season 1963-64. Engineering Division Saskatchewan Research Council, July. U. S. Environmental Protection Agency. 1971. Methods for chemical analysis of water and wastes. Water Quality Office, Cincinnati. U. S. Environmental Protection Agency. 1979. Methods for chemical analysis of water and wastes. Office of Research and Development, Cincinnati. United States Department of Agriculture. 1954. Saline and alkali soils. Agriculture Handbook #60. U . S. Government Printing Office, Washington, D . C . 91?

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