Successful reclamation of mined lands is an important ecological and economic process recognized by the Erosion Control Technology Council (ECTC). ECTC is a leading industry organization home to top manufacturers of erosion and sediment control products, component suppliers, material distributors and test laboratories. ECTC members are dedicated to advancing the knowledge, experience and expertise of erosion and sediment control.
The nonprofit organization’s mission is to develop performance standards, uniform testing procedures, and guidance on the application and installation of hydraulic erosion control products (HECPs), rolled erosion control products (RECPs) and sediment retention fiber rolls (SRFRs). ECTC recently expanded its reach to other technologies as well, and it promotes the use of erosion and sediment control products through industry leadership and education in the hope of making a substantial contribution to the science of erosion control and environmental preservation.
ECTC’s expertise applies directly to the mining industry and can help return land to a state that meets or exceeds pre-mining conditions, as required by the 1977 Surface Mining Control and Reclamation Act. Together, we have worked to provide successful solutions on mining sites for decades. There are many different types of mines, so the challenges across them vary. ECTC’s toolbox of specifications and applicable products, which have been verified through standardized industry testing, are perfect fits for the erosion and sediment control challenges of the mining world. Also located in ECTC’s toolbox online are CAD installation drawings, installation instructions, “how to” installation videos and fact sheets about each technology type.
HECPs and RECPs are successful solutions to many revegetation needs at mining sites. Both technologies contain features and benefits to consider for basic revegetation requirements. There is a time and place for both at mines.
Slope erosion control needs present themselves during and after mining activities. According to the ECTC specifications, HECPs provide protection on slopes ranging from flat areas to up to 2H:1V steepness. HECP functional longevity, depending on the chemistry and fibers used, ranges from one to 12 months.
RECPs are another slope erosion control solution for mines. RECPs contain physical bonds from stitching, weaving and/or netting that provide tensile that is important for longer slopes, human and wildlife foot traffic areas, and all other areas and conditions where chemical bonds are not sufficient. RECP functional longevities range from a few months with the quickest degrading erosion control blanket (ECB) to turf reinforcement mats (TRMs) that are not intended to degrade. RECPs can be successful solutions on slopes up to 1H:1V for the top end ECBs and up to 0.5H:1V slopes for TRMs.
Channelized flow conditions are present at several types of mining sites. The need to move water safely from one part of the operation to the other without causing excessive erosion is a common need at mines. ECBs and TRMs are both suitable options depending on the design requirements and how long the RECP needs to last. There are many ECBs available to meet the varying conditions, with Type 4 ECBs having the highest permissible shear stress of 2.25 pounds per square foot (108 Pa) according to ASTM D6460 testing. TRMs have a minimum unvegetated permissible shear stress requirement of 2.0 pounds per square foot (96 Pa) according to D6460, but vegetated TRMs have a minimum vegetated permissible shear stress of 14.0 pounds per square foot (670 Pa). TRMs verified to meet design requirements have been used to successfully replace rock riprap down shoots at some mines. In addition, TRMs are utilized to reinforce vegetation in ditches next to haul roads at mining operations. Several ECTC directing members have free erosion control software programs to determine which product will be suitable for your specific mine conditions.
SRFRs are another tool in the best management practice toolbox to provide sediment control benefits across mines. SRFRs are commonly placed across slopes at mines to break up the effective slope length and prevent concentrated flow conditions from developing on the slopes. SRFRs are also commonly used in areas of channelized flow. There are two types of SRFRs, depending on the goal of the installation. Most SRFRs are designed to be dense products to pool flows; however, some SRFRs are designed to be porous so contaminated runoff can flow through their matrix and be filtered.
ECTC members recognize that soil health is critical to our success. Several BMPs used at mining sites depend on vegetation as the long-term erosion control solution. Thus, it is imperative to conduct soil tests before deploying seed and erosion control or revegetation products. Soil amendments may also be needed as part of the solution to support long-lasting vegetation, which is the ultimate goal of many mine sites. Synergistic approaches that utilize HECPs, RECPs, SRFRs, and other erosion and sediment control products have proven successful at mine sites in the past and will continue to help solve their challenges into the future.
Please contact Jon Curry (firstname.lastname@example.org), ECTC executive director, with any questions or comments regarding this article. He will be sure to communicate your questions or comments to ECTC membership, then provide a timely response.
Kurt Kelsey is the president of the Erosion Control Technology Council and division director of the Earth Science Division at American Excelsior Company. The Erosion Control Technology Council (ECTC) is committed to promoting cost-effective erosion and sediment control solutions through leadership, standardization and education. ECTC assists agencies, engineers, designers, contractors and other entities in the proper application, installation and specification of erosion and sediment control technologies while establishing guidelines for product quality, testing and performance.