U.S. Natl Park Service - Grand Canyon National Park – Emissions Trend

This page assembles 5 consecutive years of EPA Toxics Release Inventory Form R filings for U.S. Natl Park Service - Grand Canyon National Park, spanning 2019–2023. Each annual total aggregates on-site air emissions, surface-water discharges, land disposal, and off-site transfers reported by the facility under EPCRA Section 313, which requires disclosure whenever a listed chemical is manufactured, processed, or otherwise used above threshold quantities.

Reported releases opened at 21.2K in 2019 and closed at 10.6K in 2023 – a decrease of 49.7% over the window. The chart below stacks the four TRI release media (air, water, land, off-site) and overlays the yearly total. The top contributor by cumulative mass is Chlorine at 55.5K, followed by Mixture at 20.7K.

Because TRI figures are estimated, not metered, year-over-year deltas can reflect methodology revisions, ownership changes, or shifts in what a facility classifies as reportable, not only physical emission changes. Treat the trajectory as a disclosure record, and cross-reference with the EPA Enforcement and Compliance History Online (ECHO) system for the fuller regulatory picture on this hazardous waste facility.