Data Analysis

PFAS MCL Compliance and Groundwater Reporting: What Comes After the April 2024 Final Rule

PFAS MCL compliance for water systems: EPA Method 533 vs 537.1, ppt-level sampling procedures, non-detect reporting, and groundwater site cleanup framework.

compliance reportingnpdes permittingdata analysis

June 3, 2026

Groundwater Monitoring Well Sampling Frequency: How Regulatory Programs Set the Schedule

RCRA, Superfund, and NPDES groundwater monitoring frequency requirements—plus how to request a reduction using Darcy velocity and Mann-Kendall stability data.

groundwater monitoringcompliance reportingdata analysis

May 31, 2026

Water Quality Trend Analysis: A Mann-Kendall Worked Example for Compliance Monitoring

Mann-Kendall worked example for water quality trend analysis: S statistic, variance, Z-score, and significance with 8 quarters of TCE data.

data analysisgroundwater monitoringmann kendall

May 5, 2026

Water Quality Data Gap Filling Methods for Environmental Consulting: Non-Detects, Kaplan-Meier, and ROS

Water quality data gap filling methods for environmental consulting: non-detect substitution, Kaplan-Meier, ROS, and when each applies.

data analysisnon detectsqa qc

April 21, 2026