ST. LOUIS (August 31, 2016) – Southeast Missouri is home to one of the world’s largest lead mining districts where mining dates back hundreds of years, leaving mining companies like The Doe Run Company (Doe Run) continually looking to improve the process for remediation of former mine sites. New award-winning research conducted at Missouri University of Science and Technology (Missouri S&T) holds promise for a new way to help mining companies return former mine sites in the centuries-old Missouri district and other locations to productive use.

Mariam Al-Lami, a doctoral student in civil and environmental engineering at Missouri S&T, earned the top student paper recognition from the American Society of Mining and Reclamation (ASMR) for her research on soil-enhancing additives to encourage plant growth at mine tailings sites. The research, conducted by Al-Lami and Joel Burken, Curators’ Distinguished Professor and chair of the civil, architectural and environmental engineering department, could be the answer to revegetating tailings impoundments as a part of the remediation of mine sites. Doe Run supported the research with $50,000 in funding over a three-year period.

Al-Lami studied the effectiveness of applying biosolids, and other soil-enhancing additives, to mine tailings in order to encourage vegetative growth. Mine tailings are the ground-up rock byproducts created when separating mineral from waste rock as part of the milling process. At historic mine sites, these tailings often were collected and stored in tailings impoundments.

In her research, Al-Lami treated tailings with sewage sludge from a municipal wastewater treatment plant to add needed nutrients to the soil. These biosolids, along with other additives, were tested on vegetation, including willow and poplar trees, to assess their utility in promoting growth atop the tailings impoundments.

“Conventional reclamation of mine tailings sites involved placing soil over the tailings and then revegetating the sites,” said Chris Neaville, Doe Run asset development director. “In arid locations or places with poor or thin soil, trucking in large volumes of good soil is impractical.  These findings indicate we might minimize the need for soil by adding biosolids and planting specialty vegetation, such as Miscanthus grass, which has an extensive root system that adds nutrients and biomass to the tailings. Once the site can support vegetation and nature takes its course in conditioning the soil, we can introduce native grass species to create a more natural habitat.”

“Miscanthus is proven to be one of few plants that can thrive in challenging conditions, such as tailings,” says Dr. Eva Gonzales, a Saint Louis University plant biologist and a member of Al-Lami’s dissertation committee.

The study also evaluated willows and poplars, and determined they are also well suited for mine sites, particularly in shallow water conditions. These trees and Miscanthus are ideal “pioneer species,” which means they can grow quickly and provide nutrients to improve soil conditions.

Through the research, Al-Lami concluded that the tailings amended with biosolids “dramatically improved plant growth” by promoting microbial activity essential to plant health.

“This work has been very rewarding on many levels,” says Burken. “Working collaboratively with Doe Run, we are looking at long-term solutions. Balancing development and societal gains with ecological restoration is really the core of our field.”

“Doe Run looks forward to the next phase of this study, which will include field trials based on Al-Lami’s research,” adds Neaville, an S&T graduate with a bachelor’s degree in geological engineering. “Thanks to this research, we better understand another way to reclaim historic mine sites and return them to a more natural state.”

The ASMR presentation by Burken and Al-Lami is titled, “The potential of biosolids and other amendments for revegetation of lead/zinc mine tailings with three biomass crops: greenhouse study.” Al-Lami, an Iraq native, also received an ASMR scholarship to attend the conference, including a $2,000 award, to present her research findings at the recent Ecological Society of America conference in Fort Lauderdale, Florida.

About The Doe Run Company

Based in St. Louis, The Doe Run Company is a privately held natural resources company and a global provider of lead, copper and zinc concentrates. Dedicated to environmentally responsible mineral and metal production, Doe Run operates one of the world’s largest, single-site lead recycling centers, located in Boss, Mo. The Doe Run Company and its subsidiaries deliver products and services necessary to provide power, protection and convenience. Doe Run has operations in Missouri, Washington and Arizona. For more information, visit and

About Missouri University of Science and Technology

Founded in 1870 as the University of Missouri School of Mines and Metallurgy, Missouri University of Science and Technology (Missouri S&T) is a research university of nearly 9,000 students and part of the four-campus University of Missouri System. Located in Rolla, Mo., Missouri S&T offers 97 different degree programs in 39 areas of study, including engineering, the sciences, business and information technology, the humanities, and the liberal arts. For more information, visit