What's New in Construction Waste Management?

A few years ago, construction waste management and job-site source separation would have been considered nearly synonymous. It makes sense, after all, that if the materials have more value when separated by type, we should try to avoid mixing them together in the first place. While source separation still makes sense for many jobs and for certain materials, as waste management specialists get more involved in construction waste there is a growing trend “backwards,” towards single-bin disposal. Some contractors are finding such comingled disposal more cost-effective, and waste management companies can often recycle more of the material when they do the separation at a specialized facility.

In spite of the increasing value of many reclaimed materials, the economics of recycling continue to be dominated by the avoided tipping fees, or disposal costs, at conventional landfills or incinerators. There are many more waste management options available to contractors in regions with high tipping fees. Whatever the options, every construction and renovation job should have a waste management plan to avoid unnecessarily high disposal costs and to recycle as much of the discarded material as possible. This article looks at the pros and cons of various waste management approaches, and suggests which might work best for each type of job.

Many state and local regulations and incentive programs focus on diversion of material from overburdened (or soon to be overburdened) landfills, but some contractors and recyclers are also interested in promoting the highest and best use of the recycled material. While scrap gypsum wallboard can be converted into a soil amendment, returning it to the manufacturer for use in making new wallboard, where possible, is generally considered a preferable option. Whatever the approach, ancillary environmental impacts such as transportation requirements and processing issues should also be considered if you have a choice as to how your waste material is recycled.

Another example is wood “recycling,” which in many areas consists of converting clean wood waste into hog fuel for cogeneration or other energy use. In fact, researcher Peter Yost at the NAHB Research Center reports that the feasibility of diverting wood waste from construction sites in some regions is directly related to the existence of a local wood-burning power plant. While such a use may be preferable to landfilling the material, there is increasing interest in converting wood waste into higher-value products such as particleboard, landscaping mulch, or compost. California’s Assembly Bill 939, which requires a 50% reduction in the amount of solid waste disposed of by the year 2000, does not recognize the burning of waste wood as diversion, but does allow its use for mulch and compost.

The most appropriate strategies for managing construction waste on any particular job depend on many factors. The size and nature of the building under construction, the types of waste generated, recycling facilities available in the immediate area, tipping fees at landfills or incinerators, and the experience level of construction crews will all impact the dynamics and economics of waste management. Some strategies, notably source separation, rely heavily on participation by construction workers, while others relegate all additional tasks to specialized waste handlers. For the sake of simplicity, we’ve condensed the various options into these three general strategies: source separation, time-based separation, and comingled delivery to off-site separation.