Towards a multi-faceted Vadose Zone Assessment Protocol : cemetery guidelines and application to a burial site located near a seasonal wetland (Pretoria, South Africa)

摘要

Cemeteries are generally considered low-risk landfills and are,therefore, not adequately governed in terms of minimum requirements forengineering geological and hydrogeological investigations. With the decay ofhuman bodies, bulk of the contaminant load typically is present within one yearof burial and decreases over time. Further controls include adsorption ofpathogens and particulates to soil in the vadose zone and eventual breakdown inchanging aerobic and anaerobic subsurface environments. A case study ispresented where a cemetery has been active for decades and contains in excessof 18 000 human bodies. With recent expansion, water seepage was identifiedinto newly excavated burial pits and all further development has ceased. Trialpitting and detailed soil profile descriptions are used to infer hydrologicalinteraction at the site and to address possible contamination pathways. Futurework is recommended with respect to water quality, although valuable insight isprovided to the consequences of improper ground investigation prior todevelopment. Final comments are made regarding provisional guidelines in the forms of a Cost-Effort-Risk Screen and a multi-faceted Vadose Zone AssessmentProtocol.