June 17, 2010
Case studies are helpful in showcasing “real world” examples of different foundry sand reuse scenarios. Since most foundry sand is used in local construction projects or supplied as an aggregate substitute for the manufacture of other products (cement, concrete, asphalt, etc.), there is no comprehensive listing of the hundreds of successful foundry sand projects in the United States. However, the AFS benchmarking survey in 2007, as well as other individual state surveys and conference presentations, have made it clear that foundry sand reuse is alive and well in the states whose regulatory agencies promote its use.
General Case Studies
Following the completion of the benchmarking study, AFS-FIRST and U.S. EPA each produced an initial set of case studies from examples chosen from different states and different applications:
Case Study: A Resource Recovery Corporation
A foundry-owned processing cooperative in western Michigan processes sand from multiple foundries. Principal markets include asphalt paving, landfill liners, and manufactured soils.
Case Study: Foundry Sand as a Manufactured Potting Soil
A near-by potting soil facility blends local peat moss with foundry sand from an Indiana foundry.
Case Study: The City of Reedsburg Industrial Park
An industrial park in Reedsburg, Wisconsin, was developed on a 35 acre site, ultimately using some 230,000 cubic yards of foundry sand.
Case Study: Foundry Sand as an Alternative Raw Material in the Manufacturing of Cement
A Michigan cement manufacturer works with foundries in Iowa, Minnesota, Wisconsin and Illinois to reuse 75,000 tons of sand annually.
Case Study: Foundry Sand as an Asphalt Pavement Ingredient
An Indiana foundry supplies sand for asphalt pavement at a high performance test track.
Case Study: Foundry Sand in Land Application
A raingarden is a type of landscape in which the soils and plantings are designed to absorb and filter stormwater runoff to remove impurities before the water enters storm drains or surface waters. This example, in the City of Seven Hills, Ohio used foundry sand to install a raingarden on community property near City Hall.
Case Study: Foundry Sand in Residential Home Construction
A Tennessee foundry supplied foundry sand as structural fill for residential construction projects.
Case Study: Foundry Sand as Structural Fill
A Wisconsin foundry supplied 38,000 tons of foundry sand for site development for a national “big box” retail store.
Case Study: Foundry Sand in Land Application
An Indianapolis foundry supplied 75,000 tons of foundry sand for the creation of a berm at the Marion County Fairgrounds.
Case Study: Foundry Sand as Backfill Material
A Wisconsin foundry beneficially reused 80,000 tons of foundry sand to backfill an old gravel mining pit.
Case Study: Foundry Sand as Structural Fill and Road Base
A Pennsylvania aluminum foundry supplied used sand for a number of local construction projects.
Case Study: Foundry Sand as Subbase Fill for an Airport Runway
A Wisconsin foundry supplied iron green sand as subbase for a commercial airport runway.
Case Study: Foundry Sand for Roadbase and Manufactured Soil
A Pennsylvania coal mine was reclaimed using foundry sand, some of it blended into a manufactured soil.
Article: Texas Facility Turns Foundry Sand into Paydirt
A large steel foundry in Ft. Worth, Texas, instituted a comprehensive recycling and reuse program that reduced costs by more than $65,000 per month. Most of the foundry’s sand is blended with crushed concrete and sold as stabilized roadbase for local construction projects.
Kohler Aims for Cleaner Bodies and a Cleaner Environment–Foundry Sand
US EPA news article on Kohler’s successful endeavors in working with the Wisconsin DOT and other parties to recycle their foundry sand as a subbase for roads and other construction applications.
Technical Case Studies
For larger highway projects, engineers and project designers require detailed design and specification information. For “alternative” materials like foundry sands, engineers also need to understand any issues relating to construction practices. In an attempt to evaluate these issues, FHWA engineers paid site visits to a number of highway projects in northeast Ohio and prepared a report that is posted on the FHWA website:
Report on Use of Recycled Foundry Sand in the Cleveland Area
FHWA and RMRC also cooperated to produce a set of technical case studies showcasing the most common uses for foundry sand in highway construction projects. These and future case studies can be found on the RMRC site at http://www.rmrc.unh.edu/materials/fs/casestudies.asp
Case Study: Foundry Sand in Embankments and Fill
The nation’s Interstate highway system is the backbone of our transportation network, moving millions of cars and tons of freight each year. Interstate construction projects have tight specifications and deadlines. A project to reconstruct an interchange on I-94 near the Milwaukee airport is one example of how foundry sand can meet stringent technical requirements while saving money for departments of transportation.
Case Study: Foundry Sand as MSE Wall Backfill
An Ohio contractor used foundry sand as reinforced structural fill under the approaches to a bridge replacement project for the CSX Railroad. The sand met Ohio DOT Supplemental Specification 871, “Embankment Construction Using Recycled Materials.” The foundry sand supplier, Kurtz Bros., Inc., has supplied more than 250,000 cubic yards of foundry sand for similar highway projects in the past decade.
Case Study: Foundry Sand in Subbase Layers
To address a widespread problem with soft native soils, the Wisconsin Department of Transportation cooperated with the University of Wisconsin-Madison (UW) on a pilot project to assess alternative subbase construction materials. In 2000, foundry sand was placed under a test section of State Highway 60 near Lodi, Wisconsin. The project has been monitored by WisDOT and UW for more than a decade. The foundry sand is performing very well and has been used in other WisDOT projects. In addition to its technical performance, data have been gathered on the comparative environmental impacts of the foundry sand and other materials in the test sections.