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Six-Year Review 1 Contaminant Occurrence Data (1993-1997)

In July, 2003 EPA announced the review results for the Agency’s first Six-Year Review (called the Six-Year Review 1). EPA completed its first detailed contaminant occurrence analyses in 2003 for 69 regulated contaminants, using data provided by a national cross-section of 16 states. Most of the sample data were collected between 1993 and 1997.

Six-Year Review 1 Contaminant Occurrence Data

The Six-Year Review 1 MS Excel PivotTables® below contain summary occurrence data used in developing the first Six-Year Review of national primary drinking water regulations. Download the tables by selecting the link below:

Six-Year Review 1 Occurrence Data Pivot Table(2 pp, 5 MB, September 2002)

Data included in the Six-Year Review 1 PivotTable

This PivotTable contains information on Six-Year Review 1 sample data including:

  • # analyses performed
  • # PWSs with analyses
  • # detects
  • # PWSs with detects (analytical detections above the reporting limit)
  • minimum detect
  • maximum detect
  • mean detect
  • minimum non-zero MRL
  • maximum MRL
  • mean non-zero MRL

Any or all of the above facts for a contaminant can be categorized by any combination of the following water system attributes:

  • EPA Region
  • State
  • Water system type
  • Size category *

-or any combination of the following sample attributes:

  • Sample collection year *
  • Source water type where the sample was taken *

* To avoid double-counting, the Pivot Tables will not sum the number of PWSs with and without detects across this dimension/attribute. Details on these attributes are provided in the Pivot Tables.