MINIMUM THICKNESS OF COMPACTED SOIL LINERS .1. STOCHASTIC-MODELS

Regulatory agencies often specify a minimum thickness of compacted soi l liners that will ensure that the liner performs adequately. No conse nsus has been formed, however, on an appropriate minimum thickness. In some states soil liners may be as thin as 60 cm (2 ft), whereas in ot her states soil liners are required to be at least 360 cm (12 ft) thic k. Difficulties encountered in the analysis of soil liners, such as un certainties in construction, flow in macropores, and spatial variabili ty of hydraulic properties, and variability in past experiences of reg ulatory agencies are the most likely reasons for the lack of consensus on minimum thickness. In the present paper, the first in a two-parr s eries, two models of fluid now in compacted soil liners are described. These models incorporate pow in macropores, spatial variability, and uncertainty via probability theory, but only consider advective transp ort in saturated soil. In the second paper, the models are used to ide ntify an appropriate minimum thickness of soil liners.