Toward Building up Good Examples of Remediation of Nitrate Contaminated Groundwater

Abstract

Groundwater contamination by nitrogen has been a serious problem in the world. Although many measurements such as the enactment of environmentrelated laws, proper application of fertilizers, and proper treatment of animal wastes have been taken, improvement or restoration of environments are not necessarily notable, especially remediation of contaminated groundwater has hardly progressed yet. Establishment of effective in-situ or on-site remediation methods for restoring groundwater environments is urgently needed. Good examples of remediation of nitrate-contaminated groundwater have to be accumulated. Permeable reactive barrier (PRB) is one of the possible in-situ methods to remediate contaminated groundwater by many contaminants including nitrate with relatively low cost of construction and maintenance. There have been only several cases of PRB applied to nitrate-contaminated groundwater in Japan, which could show their possibility. In order to make many good examples of applications, there are several essential conditions such that a method has a clear chemical remediation process and it has to be applied at good field condition such as good permeable aquifers with a proper hydraulic gradient. Dimensions of the structure of PRB are also important, especially a length of the barrier is large enough to treat contaminated groundwater.