CHAPTER 6
 SUMMARY AND CONCLUSIONS


 6.1 Summary


 The adsorption, desorption and biodegradation of

phenol, 2,4-dichlorophenol and penta-chlorophenol under

simulated subsurface environmental conditions were

investigated under single-compound conditions as well as in

multi-compound solutions. These experiments were conducted

in both batch and column systems. The soil materials were

taken from the surficial sandy aquifer in an unused part of

the Southwest Landfill in Archer, Florida. They were

characterized as fine grained sands with negligible organic

carbon content.


6.1.1 Sorption


 Batch sorption data were fitted with the Freundlich

model to calculate the sorption coefficients. In single-

compound systems phenol had a very low adsorption

coefficient (KFA) of 0.0158 on this type of sandy aquifer

material. KFA for 2,4-DCP was 0.0547, and PCP was most

adsorbed with a KFA value of 1.119. In multi-compound

systems the three phenolic compounds compete for adsorption

sites, and adsorption capacities were reduced by a margin