ABSTRACT

CONTENTS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203 Objectives of Equipment Decontamination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 Current Status of Equipment Decontamination Protocols . . . . . . . . . . . . . . . . . . . . . 204 Preparing an Effective Decontamination Protocol for Field Equipment . . . . . . . . . . . 205

What Equipment Requires Field Decontamination? . . . . . . . . . . . . . . . . . . . . . . . . 205 Using Disposable Equipment to Avoid Equipment Decontamination Issues . . . . . 207 When and Where Should Equipment Be Decontaminated? . . . . . . . . . . . . . . . . . . 208

Remote Equipment Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 Field Equipment Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209

Selecting an Appropriate Decontamination Protocol . . . . . . . . . . . . . . . . . . . . . . . 212 Factors to Evaluate on a Task-Specific Basis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212 Available Decontamination Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214

Methods for Larger Support Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 Methods for Sample Collection or Analysis Equipment . . . . . . . . . . . . . . . . . 216

Inherent Problems with Decontamination Techniques . . . . . . . . . . . . . . . . . . . . . . 218 Quality AssuranceuQuality Control Components of Decontamination

Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220

As discussed throughout this text, many different types of equipment are used during a ground-water sampling event to collect samples and generate field data. Often, this equipment is used at more than one site and in more than one well, necessitating the development and implementation of an effective program for equipment cleaning, or decontamination, on a site-by-site (and parameter-specific) basis. Equipment cleaning is a critical component of any ground-water sampling program to ensure that samples obtained for field or laboratory analysis be representative, accurate and precise, and not be influenced by bias or error associated with sample collection. The economic and technical consequences associated with making decisions based on field and laboratory analyses of samples that are not representative can be substantial.