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Groundwater Monitoring Statistics
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The March 2009 Unified Guidance, “Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities”, updates and replaces the earlier 1989 Interim Final Guidance and the July 1992 Addendum. Three other documents found below—the Fact Sheet, Optimal Rank calculator and accompanying narrative—are part of the 2009 guidance.
Following the guidance release, EPA identified a number of inadvertent procedural and calculation errors. For users who have already downloaded the guidance, EPA is providing an Errata Sheet file (August 2010). The Unified Guidance files below have been edited to incorporate the changes. Print covers for the main text and appendices are also provided in these files:
- March 2009 Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities—Unified Guidance (PDF) (888 pp, 7.3MB) (Complete Document)
- Table of Contents (PDF) (14 pp, 348K)
- Part I: Statistical Design and Philosophy (PDF) (198 pp, 1.7MB)
- Part II: Diagnostic Methods and Testing (PDF) (148 pp, 1.5MB)
- Part III: Detection Monitoring Tests (PDF) (138 pp, 1.2MB)
- Part IV: Compliance/Assessment and Corrective Action Tests (PDF) (58 pp, 463K)
- Appendices (PDF) (330 pp, 2.3MB)
- Fact Sheet for the March 2009 Unified Guidance (PDF) (4 pp, 57K)
- Optimal Rank Calculator for Non-Parametric Prediction Limits* (VisualBasic6, 460K)
*Note: Some anti-virus computer software may not accept this calculator in .exe format. Please contact the EPA Program Information and Implementation Division for a hard copy. - Narrative for development and use of the Optimal Rank Calculator (PDF) (28 pp, 340K)
- August 2010 Errata Sheet (PDF) (6 pp, 135K)
Supporting Documentation for the Unified Guidance
Following release of the 2004 draft version of the Unified Guidance, numerous comments were received from states and other interested parties. In 2005, three national peer review experts provided detailed comments on the draft. For your information, the peer reviewer comments and an EPA Responsiveness Summary to these and other major concerns are found below.
- Peer Reviewer Comments(PDF) (112 pp, 616K)
- EPA Responsive Summary to Peer and Other 2004 draft Unified Guidance Comments (PDF) (57 pp, 284K)
GRITS/STAT Software
The US Environmental Protection Agency no longer supports this software.