Accession Number : ADA603804


Title :   Improved Understanding of Sources of Variability in Groundwater Sampling for Long-Term Monitoring Programs


Descriptive Note : Final rept.


Corporate Author : GSI ENVIRONMENTAL INC HOUSTON TX


Personal Author(s) : McHugh, Thomas ; Newell, Charles ; Adamson, David ; Hamel, Kate ; Molofsky, Lisa ; Beckley, Lila


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a603804.pdf


Report Date : Feb 2013


Pagination or Media Count : 765


Abstract : The overall objective of this research project has been to identify key sources of variability that influence volatile organic chemical \201VOC\202 concentration measurements in water samples collected from groundwater monitoring wells using current sampling and analysis techniques. By understanding the sources of variability in groundwater monitoring results improved sampling and analysis methods can be developed to reduce and control for sampling variability. Methods: The project has been implemented through completion of three project tasks 1. Evaluation of Existing Datasets \201Task 1\202: The initial project task utilized large existing groundwater monitoring datasets to identify key sources of variability in groundwater monitoring results. The data mining study involved i\202 identification of large databases of groundwater monitoring results, ii\202 selection of datasets from these databases that were suitable for statistical analysis, and iii\202 exploratory analysis and statistical analysis of the datasets to identify factors associated with monitoring variability. For this task, we identified three large groundwater monitoring databases: i\202 the Hill Air Force Base \201AFB\202 database, ii\202 the Marine Corps Logistics Base \201MCLB\202 Albany database, and iii\202 a database of monitoring results from 48 underground storage tank sites compiled by GSI. Because the Hill AFB database included the most comprehensive documentation, many of the analyses could only be conducted using the Hill AFB database. 2. Evaluation of Short-Term Variability \201Task 2\202: For this task, we characterized sources of short-term variability in groundwater monitoring results through a field program that involved collecting and analyzing a large number of groundwater samples from a set of monitoring wells over a short period of time.


Descriptors :   *GROUND WATER , *STATISTICAL ANALYSIS , *WATER WELLS , DATA BASES , INFORMATION RETRIEVAL , MONITORING , ORGANIC CHEMISTRY , SAMPLING , VARIATIONS


Subject Categories : Inorganic Chemistry
      Hydrology, Limnology and Potamology


Distribution Statement : APPROVED FOR PUBLIC RELEASE