Geochemical datasets frequently contain left-censored data, i.e., the actual concentration falls in the range between 0 and the detection limit (DL). These data are referred to as nondetects (NDs). An ND does not necessarily mean the analyte was not present but, if it was present, it was at a concentration below the DL. In addition to NDs, contract labs often report estimated values (often flagged with a “J”) which lie between the DL and the reporting limit (RL). The RL is the level at or above which the lab will state the result is quantitative. A common approach to statistically analyzing left-censored data is to use substitution (e.g., ½DL). Although still a common practice, substitution can introduce bias to statistical analyses. Fortunately, there are a number of statistical techniques specifically designed to handle left-censored data that do not compromise the results of statistical analyses by using substitution. All of these techniques work with NDs and some work with estimated data. There are a number of techniques for calculating summary statistics for left-censored data including nonparametric Kaplan-Meier survival statistics, regression on order statistics (ROS), and the Turnbull interval-censored method. As the name implies, the Turnbull method works with interval censored data (i.e., quantitative data ≥RL, DL-RL [estimated], and 0-DL). In the latter two cases, an interval is used, i.e., the true value lies somewhere within the interval but picking a single value such as ½DL is not required. Interval-censored data can also be used on multivariate ordination techniques such as nonmetric multidimensional scaling (NMDS) and the interval-censored score test – an analog of the generalized Wilcoxon test. Kendall’s tau (τ) is a nonparametric correlation analysis that can be applied to left-censored data. For this test, the estimated (J-flagged) values are used. Kendall’s τ is analogous to the familiar parametric Pearson’s r and, like Pearson’s r, the test for Kendall’s τ also provides a measure of the correlation significance. The case study for this presentation will include the geochemical data and statistical results from the Hawaiʻi Ordnance Reef Follow-Up investigation of the U.S. Army’s Remotely Operated Underwater Munitions Recovery System.