Concrete Washout Solutions and Environmental Impact Management
Marc Zarbis and his colleagues established our company in 2004 as a necessary tool for collecting liquid waste from concrete pump truck washout. We understand the importance of proper waste management on construction sites to protect the environment and human health. To further emphasize the significance of this issue, we have updated and clarified the content below to present a more modern and comprehensive perspective on the problems caused by liquid waste at construction sites.
Stormwater Best Management Practice: Concrete Washout
The primary objective of concrete washout best management practices (BMP) is to minimize the environmental impact of concrete waste on construction sites. Concrete washout can pose serious threats to water sources, soil chemistry, plant growth, and aquatic life.
Concrete and its ingredients:
Concrete is a mixture of cement, water, and aggregate materials. Portland cement is produced by heating a mixture of limestone and clay, which contains oxides of calcium, aluminum, silicon, and other metals in a kiln, and then grinding the resulting clinker. Sand is typically used as the fine aggregate, while gravel or crushed stone serves as the coarse aggregate. When cement is mixed with water, a chemical reaction called hydration occurs, creating a glue that binds the aggregates together, forming concrete.
Environmental and human health impacts:
Concrete washout water is a slurry containing toxic metals and has a caustic, corrosive nature with a pH near 12. This high pH can harm aquatic life, alter soil chemistry, inhibit plant growth, and contaminate groundwater. Additionally, it can cause skin irritation and eye damage to construction workers.
Best management practice objectives:
The main goals of BMP for concrete washout are:
- Collect and retain all concrete washout water and solids in leak-proof containers to prevent the caustic material from contaminating soil, surface water, or groundwater.
- Recycle 100% of the collected concrete washout water and solids.
Recycling and reuse of concrete washout materials:
The process of recycling concrete washout materials can divert them from landfills, conserve resources, and reduce environmental impact. Concrete washout solids can be reused as ingredients for ready-mixed concrete, precast concrete products, or crushed concrete products. Meanwhile, washout water can be treated and reused or allowed to evaporate, leaving only the hardened cementitious solids for recycling.
Washout containers:
Various types of washout containers are available for collecting, retaining, and recycling washwater and solids from washing down mixed truck chutes and pump truck hoppers at construction sites. Washout Pan fabricates several sizes of containment pans and tanks, which are considered the industry's best available technology for long-term use. These containers are engineered to last, safely contain liquids and solids, and can be safely lifted on job sites as they are OSHA compliant and made in North America.
Educating concrete subcontractors:
Construction site superintendents should inform ready-mixed truck drivers about washout facility locations and monitor for improper dumping of cementitious material. Furthermore, concrete washout requirements should be incorporated into contracts with concrete delivery companies.
By adopting and promoting these best management practices, we can contribute to a more sustainable and environmentally friendly construction industry.
There are many resources to learn more about SWPPP and proper use of BMP on the EPA's website or on your projects environmental plan.