Field QA/QC: Calibration Drift, Blanks & Duplicate Samples

Environmental data is only as trustworthy as the quality-assurance program behind it. This simulator places a grid of instrumented sampling stations over a wetland monitoring transect and runs the same QA/QC cycle real field programs use: sensor calibration drifts a little further from truth every day it goes unchecked, each sampling round re-measures one station as a blind duplicate to compute the Relative Percent Difference (RPD), a zero-concentration field blank checks for contamination, and every check-standard reading lands on a live Levey-Jennings control chart with ±2σ warning and ±3σ out-of-control limits. Drive the drift rate and sensor noise up to watch data quality collapse, then recalibrate to see the chart snap back in line.