Denver County SWPPP Checklist: Concrete Washout

The Rule: Water used to clean cement truck delivery chutes must be discharged into a predefined concrete washout area. The Denver Nuance: Denver explicitly states that concrete washout locations must not be located in an area where shallow groundwater may be present. If your site is near the South Platte River or Cherry Creek, unlined dirt pits are a massive compliance risk. Approved Equipment: DOTI Standard Note #8 explicitly approves the use of "commercially available concrete washout devices that fully contain all wash water" (i.e., above-grade steel pans).

The Rule: Paved and impervious surfaces adjacent to the site must be swept daily (and as needed throughout the day) if sediment or mud is tracked onto them. The Denver Nuance: While street sweepers using water for dust control are preferred, flushing or washing off paved surfaces with water is strictly prohibited. If a mixer truck tracks mud out of your washout zone, you must sweep it; you cannot hose it down.

The Rule: The direct or indirect discharge of water containing waste cement into the Denver storm sewer system is prohibited. The Denver Nuance: This isn't just a best practice; it is aggressively prosecuted under Sec. 56-102(a) and (c) of the Denver Revised Municipal Code.

The Rule: Dried cement waste must be removed from the containment area and properly disposed of. The Denver Nuance: Wash water discharged into the containment device must be allowed to infiltrate, evaporate, or be disposed of in accordance with applicable regulations. (Note: Relying on "infiltration" in Denver is highly scrutinized due to the shallow groundwater rule mentioned in Note #8). Using a watertight pan that evaporates or is hauled off-site removes this compliance headache