1.19 BMP C151 - Concrete Handling
Concrete work can generate process water and slurry that contain fine particles and high pH, both of which can violate water quality standards in the receiving water. Concrete spillage or concrete discharge to waters of the State is prohibited. Use this BMP to minimize and eliminate concrete, concrete process water, and concrete slurry from entering waters of the State.
Utilize these management practices any time concrete is used.
Concrete construction projects include, but are not limited to, the following:
Disposal options for concrete, in order of preference are:
De minimus washout to formed areas awaiting concrete
1.19.3 Design and Installation Specifications
Wash concrete truck drums at an approved offsite location or in designated concrete washout areas only.
Return unused concrete remaining in the truck and pump to the originating batch plant for recycling. Do not dump excess concrete onsite, except in designated concrete washout areas as allowed in BMP C154 - Concrete Washout Area.
Do not wash out concrete trucks onto the ground (including formed areas awaiting concrete), or into the stormwater conveyance system, open ditches, streets, or streams.
Wash small concrete handling equipment (e.g. hand tools, screeds, shovels, rakes, floats, trowels, and wheelbarrows) into designated concrete washout areas or into formed areas awaiting concrete pour.
At no time shall concrete be washed off into the footprint of an area where an infiltration feature will be installed.
Wash equipment difficult to move, such as concrete paving machines, in areas that do not directly drain to natural or constructed stormwater conveyance or potential infiltration areas.
Do not allow washwater from areas, such as concrete aggregate driveways, to discharge directly (without detention or treatment) to natural or constructed stormwater conveyances.
Contain washwater and leftover product in a lined container when no designated concrete washout areas (or formed areas, allowed as described above) are available. Dispose of contained concrete and concrete washwater (process water) properly. Always use forms or solid barriers for concrete pours within 15-feet of surface waters.
Refer to BMP C252 - Treating and Disposing of High pH Water and BMP C253 - Portable Sediment Tank for pH adjustment requirements.
Refer to the Construction Stormwater General Permit for pH monitoring requirements if the project involves one of the following activities:
Significant concrete work (as defined in the Construction Stormwatwer General Permit).
The use of engineered soils amended with (but not limited to) Portland cement-treated base, cement kiln dust or fly ash.
Discharging stormwater to segments of water bodies on the 303(d) list (Category 5) for high pH.
Containers shall be checked for holes in the liner daily during concrete pours and repaired the same day.