Colorado
For Colorado, general hazardous chemical threshold is 10,000 pounds for any other hazardous chemical; ehs threshold is 500 pounds or its TPQ, whichever is lower; special categories or chemicals is The thresholds for reporting gasoline and diesel fuel stored completely underground at retail gas stations are 75,000 gallons and 100,000 gallons, respectively; filing deadline is March 1st, verified against its source on 2026-09-22.
- State
- Colorado
- General hazardous chemical threshold
- 10,000 pounds for any other hazardous chemical verified
- EHS threshold
- 500 pounds or its TPQ, whichever is lower verified
- Special categories or chemicals
- The thresholds for reporting gasoline and diesel fuel stored completely underground at retail gas stations are 75,000 gallons and 100,000 gallons, respectively. verified
- Filing deadline
- March 1st verified
What the source says
The TPQ for a hazardous chemical is either: 500 pounds or its TPQ, whichever is lower, for the 355 chemicals listed under Section 302, also known as Extremely Hazardous Substances (EHS); or 10,000 pounds for any other hazardous chemical.
— cdphe.colorado.gov, retrieved 2026-09-22
Where each value comes from
This source states these in separate places, so each value is shown with the passage that states it.
General hazardous chemical threshold and EHS threshold
The TPQ for a hazardous chemical is either: 500 pounds or its TPQ, whichever is lower, for the 355 chemicals listed under Section 302, also known as Extremely Hazardous Substances (EHS); or 10,000 pounds for any other hazardous chemical.
Special categories or chemicals
Retail Gas Station Exception: Retail gas stations are not exempt from Tier II reporting requirements, but they do have different thresholds for gasoline and diesel stored in underground storage tanks. The thresholds for reporting gasoline and diesel fuel stored completely underground at retail gas stations are 75,000 gallons and 100,000 gallons, respectively.
Filing deadline
The Tier II reporting period opens on January 1st of each year for chemicals stored during the previous calendar year. Tier II reports are due March 1st at 5 PM MST.
— all from cdphe.colorado.gov, retrieved 2026-09-22
Source
- cdphe.colorado.govhttps://cdphe.colorado.gov/dehs/sustainability/sara-title-iii/tier-ii/faq