Field QA/QC 2D: Calibration Drift, Blanks & the Levey-Jennings Chart

Environmental data is only as trustworthy as the quality-assurance program behind it. This 2D top-down 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. Drag the map to pan and scroll to zoom the sampling grid, drive the drift rate and sensor noise up to watch data quality collapse, then recalibrate to see the chart snap back in line.