Development of a Standardized Testing Protocol for the Approval of Field-cured Products for Use on Highway Maintenance and Construction Projects
Research Idea Scope
DOTs routinely receive requests to add new products and materials to their lists of approved products, including culvert repair products and materials used for road and bridge repair. Many of these products involve a spray, foam, epoxy, or resin that require an in-the-field cure during installation. Several studies have documented potential adverse effects to water quality from the use of some of these materials. These effects are often a result of insufficient curing of the material and/or some degree of permeability in the product designed to contain the cured material.
The Virginia Transportation Research Council (VTRC) conducted a preliminary study in 2014 to develop a standardized testing method for certain pipe repair products. The researchers found that a modified Toxicity Characteristic Leaching Procedure (TCLP) was a promising test to predict leaching and product toxicity, but that further testing is needed to verify the effectiveness of this test method compared to other test methods. Once developed, a standardized testing protocol could be used by manufactures to analyze environmental impacts and certify products prior to use.
This project will develop a standardized material testing protocol for road infrastructure materials that require an in-the-field cure and are primarily used in applications that convey streams or that are in direct contact with bodies of water. The standardized test method developed should be applicable for a wide range of products and installation procedures. Such a protocol will allow DOTs to transfer the responsibility for testing the environmental impacts to the vendors prior to approval. The project findings should also be used to recommend restrictions and specifications on the use of these products
1. Gather product information for spray, foam, resin, epoxies, and other products marketed for use in transportation applications that require an in-the-field cure and that are primarily used in applications that convey streams or that are in direct contact with bodies of water. Product information includes material safety data sheets and information on installation procedures.
2. Determine potential options for material leaching test protocols that can predict the amount of contaminants released from a material in the field, such as the Toxicity Characteristic Leaching Procedure (TCLP) and Whole Effluent Toxicity tests. Researchers should verify that accredited laboratories have the ability to perform any of the material leaching test methods evaluated.
3. Determine thresholds for specific contaminant concentrations or non-specific indicators of water quality (such as total organic carbon and chemical oxygen demand) that should not be exceeded using the identified test method(s). Federal and state water quality standards and toxicity thresholds for aquatic indicator species should be used in determining these thresholds.
4. Develop a means to simulate installations of these technologies in a laboratory or controlled outdoor setting in a manner that matches the proposed uses of the products. These simulations should be used to evaluate the effectiveness of the testing protocol(s) in detecting the release of contaminants from the installation under different curing conditions (e.g. temperatures, cure time). (Using actual field installations to evaluate the test protocols is one option for product evaluation but should not be the basis for the study because of potential difficulty with identifying a sufficient number of installations within the timeline of the project.)
5. Determine the test method(s) that can best detect contaminant leaching on the simulated installations. The test method should be applicable to a range of products and chemicals.
6. Prepare the following deliverables: (1) a research report documenting the methods applied and the study results, (2) the standardized test method, including sampling procedures and laboratory testing methods, and (3) a proposed set of limitations on the placement of such materials that can be used in specifications for construction/installation.
Urgency and Payoff
As new infrastructure construction and rehabilitation materials are continually introduced into the transportation market, the costs of evaluating the environmental impact of each product is not sustainable for DOTs. This project will result in standardizing the testing protocols and transferring the testing responsibility to the manufacturers, saving DOTs costs and reducing the risks of approving products that may result in adverse environmental effects. It will also provide an additional level of reliability against stream contamination by putting in place safeguards against the use of materials that could adversely affect aquatic life.
This research proposal is supported by the TRB Standing Committees on Resource Conservation and Recovery AMS20 (David Wilson – Chair) and Environmental Analysis and Ecology AEP70 – (Bridget Donaldson – Member)