<p><p><strong>Reference(s):</strong></p><p><em>Baker (1983)<br>Waller et al. (1983)</em></p><p><strong>Method Summary</strong></p><p>This method uses transmission of electromagnetic waves through the ground to define changes in soil stiffness and extent of the grout treated zone. Grouted soils attenuate the electromagnetic waves more than ungrouted soils. Surveys should be performed before grouting and after. The two data sets obtained are compared to determine the change in the properties of the grout zone.</p><p><strong>Accuracy and Precision</strong></p><p>Accuracy and precision of these measurements are hard to quantify due to the nature of these measurements.</p><p><strong>Adequacy of Coverage</strong></p><p>This method is able to evaluate a large area of the grout zone.</p><p><strong>Implementation Requirements</strong></p><p>Proper equipment operation and detailed interpretation of the data obtained requires training and experience. Initial equipment costs can be high.</p><p><strong>General Comments</strong></p><p>This method can be applied to all rated applications and provides valuable QA information.</p></p>