RITE-TOKYO-MINATO LABORATORY,
RITE-KIYOSE NO.3 LABORATORY
in Obayashi Corporation

1. Objectives

Leaching of toxic substance from some factories or industrial waste repositories keeping toxic wastes currently becomes a serious problem. There is an urgent need to reliably contain such a contaminated area until completion of the treatment of its toxicity and the recovery of its environment. However, any reliable technologies have not been realized yet. In regard to the technology for containment of contaminated area, vertical walls around buried wastes is a common method to date and its reliability is indeed low because of its dependence on impermeable layer which may be incomplete. This R&D project targets on three-dimensional and multi-purpose barrier which involves vertical and bottom walls and which accomplishes various treatment alternatives.

2. Contents

Our multi-purpose barrier will have two functions as below:

(i) Impermeable barrier : targets on full containment of buried wastes

(ii) Accumulation barrier : collects polluted water of concern in situ and removes them from the barrier

This R&D project will address consideration of barrier materials, emplacement methods, integration of various advanced instrumentation for more direct measurements and monitoring, and demonstration.

3. Achievements in 2002

(1) Improvement of barrier materials

1)design of barrier structure and fabrication of each real-size model

Improvement of grouting method and injection materials

(2) Development of the inspection technology

Consideration of an inspection method with radioisotope and ultrasonic technology for identification of the barrier defects

Preliminarily test for application of those technologies

Demonstration test and evaluation

(3) Demonstration

Design of an artificial ground

Demonstration test of impermeable barrier with the real-size model

Evaluation of the install method

Evaluation of the hydraulic conductivity of the impermeable barrier