Statistical Analysis of Ground Water Quality Data

by Hugo A. Loaiciga, Univ of California, Santa Barbara, United States,

Document Type: Proceeding Paper

Part of: Water Resources Planning and Management and Urban Water Resources


The Resource Conservation and Recovery Act (RCRA) requires owners and operators of hazardous waste facilities to utilize design features and control measures that prevent the release of hazardous waste into ground water. These regulations require that a statistical method and sampling procedure approved by the EPA be used to determine whether there are releases from regulated units into ground water. The guidelines currently approved by the EPA (1989) prescribe statistical methods to test hypothesis regarding the presence of ground water contamination based on chemical data. The hypothesis that can be tested encompass the following situations: (1) comparisons of chemical concentrations between background and compliance wells; (2) comparisons of chemical concentrations at wells with fixed standards; (3) intrawell comparisons of chemical concentration variability over time with background well data; and (4) comparisons as in (2) and (3) when the chemical data has many 'nondetects' (i.e., data are reported as 'below detection level'). The current methods for ground water quality analysis are summarized and their assumptions highlighted according to their applicability to field conditions. Our review of the EPA (1989) guidelines indicates a need for extending these statistical methods to include: (i) geo-statistical methods, and (ii) space-time methods, to account for the spatial and temporal dependence of ground water quality data.

Subject Headings: Groundwater quality | Chemicals | Comparative studies | Recycling | Environmental Protection Agency | Statistics | Hydrologic data | Materials processing

Services: Buy this book/Buy this article


Return to search