River Mine Reclamation

An abandoned limestone quarry had subsidences (for example, sinkholes) up to 20 feet deep along a 600 foot-long embankment wall. To eliminate the risk of wildlife, livestock, or people being trapped in the subsidences, Herrera investigated their cause and determined large voids had opened below the embankment wall over time—a result of surface erosion. We designed and oversaw construction to expose the voids, backfill them with earth and controlled density fill, and rebuild the embankment and prevent future subsidences from developing. We designed the new embankment to convey water from the natural topography above it and to blend in with the surrounding topography while reducing surface erosion. The site was planted with a native seed mix to stabilize the site with vegetation over the long term.