 |
 |
 |
 |
|
| back | ||||
Abstract
Cleaning Up Geochemical Data
Track: Water Resources
Author(s): James Bollinger, John Reed
Over the past 20 years, the Savannah River Site (SRS) has collected field and geochemical data from a network of more than 2,000 groundwater monitoring wells. This data, which is housed in an Oracle relational database, has been collected to support the extensive groundwater remediation and surveillance monitoring programs at SRS and to show compliance with state and federal regulations. As with any sizable archive of scientific data, a small amount of suspect historical data is present in the geochemical database-resulting, for example, from a misplaced decimal point in a measured numerical value.
This suspect data can present a significant problem when analyzing and computing long-term statistics for a particular well and analyte or field parameter. For example, water level elevation contours and gridded surfaces are derived on an annual basis for regulatory reporting and analysis purposes. A single suspect water elevation value can significantly impact the long term average water level for a single well. The aggregate impact of such suspect data has a nontrivial impact on the derived water level contours and grids.
A powerful ArcView extension has been developed to remedy this problem. The extension contains functions to pull the desired time-history data from the database, display the data on a well-by-well basis as a series of browsable time-history scatter plots, and provide a tool for identifying and removing suspect data. Once the suspect data is removed, long-term statistics can be computed, saving weeks of effort.
James Bollinger
Westinghouse Savannah River Company
Savannah River Technology Center
Bldg. 786-6A Rm. 7
Aiken , SC 29808
USA
Phone: (803) 725-8253
Fax: (803) 725-2956
E-mail: james02.bollinger@srs.gov
John Reed
Westinghouse Savannah River Company
Environmental Protection Department
Bldg. 742-A
Aiken 29808
USA
Phone: (803) 725-8517
E-mail: john.reed@srs.gov