ProUCL version 5.1.002 (5.1) is the latest update of the ProUCL statistical software package for analysis of environmental data sets with and without nondetect (ND) observations. The ProUCL software is available at https://www.epa.gov/land-research/proucl-software. In this first installment of a three part ProUCL e-learning seminar series, instructors will present the live interactive use of ProUCL v5.1 from initial data loading, all the way through the major steps of statistical data analysis in ProUCL. General talking points will include Data managementDQO based sample size estimationProUCL options for dealing with non-detectsGraphical displaysData based statistical testingUTL/UCL observation and comparison A modified version of the Iris flower dataset (XLS) will be used as an example throughout the presentation. This dataset is provided here and it is encouraged for attendees to follow along on their local machine. To view this archive online or download the slides associated with this seminar, please visit http://www.clu-in.org/conf/tio/ProUCLAtoZ1_012720/