Modification of the Bouwer and Rice Method to a Cutoff Wall with a Filter Cake

Abstract

The Bouwer and Rice method is a line-fitting method used to estimate the hydraulic conductivity of an aquifer by means of a slug test. When considering a relatively impermeable layer, called a filter cake, which may form at the interface between a cutoff wall and the natural soil formation, the assumptions of the Bouwer and Rice method are violated. A modification of the Bouwer and Rice method is proposed that incorporates the concept of a flow net, whereby the geometry of the cutoff wall and filter cake is effectively considered in estimating the hydraulic conductivity of a vertical cutoff wall.

Stochastic analysis of the efficiency of coupled hydraulic-physical barriers to contain solute plumes in highly heterogeneous aquifers

“…Slug tests were performed on micropiezometers, and 𝐾 𝑤 was estimated from the interpretation of hydraulic tests using the method by Bouwer and Rice (1976). This type of tests is widely adopted for the analysis of insitu 𝐾 𝑤 , (e.g., Britton et al, 2002;Choi and Daniel, 2006;Choi et al, 2014;Lim et al, 2014;Nguyen et al, 2010). CPTU tests were performed following the methodology by Manassero (1994).…”

Analytical solution for transient groundwater flow during slug test in vertical cutoff walls

“…In this paper, to account for the outer boundary of cutoff walls at a finite distance from a well, the method of images is implemented in an analytical solution proposed by Hyder . The derived analytical solution for the vertical cutoff wall considers two types of boundary conditions: (i) the constant‐head boundary condition, for the case in which the hydraulic conductivity of the vertical cutoff walls is considerably lower than that of an aquifer, and for which a filter cake does not exist and (ii) the no‐flux boundary condition, for the case in which a filter cake, which is extremely less permeable than the backfill materials, does exist between the vertical cutoff wall and the surrounding soil formation ). A well offset effect, which usually occurs due to bad construction, is also considered in the solution.…”