5 Colo. Code Regs. § 1001-11-A
Some proposed planned ignition prescribed fire projects for grassland and forest management may emit relatively low amounts of smoke and emissions and be below the de minimis threshold of a low potential for smoke impacts. If so, such projects may apply for a general open burning permit. Alternatively, if a project is above the de minimis threshold, then such projects must apply for and may obtain a planned ignition fire permit. To determine whether a proposed planned ignition prescribed fire is above or below the threshold for low potential smoke impacts, the Division must consider the following factors:
1. Size of the project;
2. Fuel type
3. Duration of the project including smoldering and potential for nighttime smoke; and
4. Proximity of the project to smoke sensitive areas
Projects meeting the following guidelines will be considered to have low potential for smoke impacts for the first three factors:
De Minimis Threshold for Open Burning Permits
Type of Project | Thresholds |
Broadcast Burn | < 10 acres of grass OR < 5 acres of other vegetation |
Pile Burn | All piles out cold before sunset, AND No more than 50 piles total in the project |
The final factor, proximity of the project to smoke sensitive areas will be addressed with project permit conditions. The Division may apply the factors and approve different De Minimis Thresholds for good cause shown.
5 CCR 1001-11-A