Applicability of Slug Interference Tests for Hydraulic Characterization of Unconfined Aquifers: (2) Field Test Examples

Slug interference testing may be particularly useful for characterizing hydraulic properties of aquifer sites where disposal contaminated ground water makes pumping tests undesirable. The design, performance, and analysis of slug interference tests for two field test examples are presented. Results were compared with standard constant-rate pumping tests. The comparison indicates that slug interference tests provide estimates comparable to those obtained from short duration pumping tests for the determination of transmissivity, storativity, and vertical anisotropy. The close agreement in hydraulic property values obtained using the two test methods suggests that slug interference satin under favorable test conditions (for example, observation well distances less than or equal to 30 m), can provide representative aquifer characterization results. The quality and extent of test data obtained also indicate the potential use of slug interference testing for three-dimensional hydrologic characterization investigations, when conducted using multilevel monitoring facilities.