WorldWide Drilling Resource

49 JULY 2022 WorldWide Drilling Resource® Ten-year Pipeline Study Highlights Land Reclamation Success Adapted from Information by TC Energy Following a ten-year research project on rare plant species, a research team recently published papers highlighting the success of land reclamation efforts since construction of the Keystone Pipeline. Before construction of Keystone began in 2009, TC Energy partnered with Dr. M. Anne Naeth, a professor of land reclamation and restoration ecology at the University of Alberta, Canada, to establish a monitoring program along approximately seven miles of the project’s corridor. Dr. Naeth and her graduate students conducted rare plant surveys each spring and assessed soil and plant communities over a ten-year period with the goal of understanding impacts of pipelines on the prairie landscape. The pipeline, which went into service in 2010, safely transports crude oil from Hardisty, Alberta, to U.S. markets. It passes through dry, mixed-grass prairies in Alberta, a habitat for slender mouse-ear cress and tiny cryptanthe, two rare plants federally listed as species at risk. Research results indicate even sensitive, arid habitats could recover within a short period of time. If proper mitigation measures and construction techniques are applied, native grasses and wild flowers return to the landscape. “The minimal disturbance techniques used on these sections of the pipeline were effective at reducing impacts on soil and plant communities both on and off the right-of-way in dry, mixed-grass prairie,” said Dr. Naeth. “We wanted to have the lightest touch on the landscape as possible,” said Jennifer Barker, professional biologist and environmental planner at TC Energy. During the pipeline’s construction, the project team reduced impacts on the land through a variety of methods including: e Narrowing the corridor to minimize the construction footprint. e Installing geotextiles, soil ramps, and matting to protect the sod layer. e Constructing in frozen or late fall conditions while plants were dormant.e Replacing topsoil before the growing season began, so seeds stored in topsoil had a chance to reestablish in the same season.e Minimizing the crew size, number of vehicles, and equipment to reduce unnecessary impact. Barker said the team learned a great deal about the ecology and population of rare plants studied over the past decade. The researchers also gained knowledge about native prairie recovery, which is important for grassland conservation and management. “We learned things that would only be possible during a long-term study. For example, we confirmed that the slender mouse-ear cress is disturbance adapted,” said Barker. Historically, the plant thrived in soil frequently disturbed by bison hooves. Today, the plant is rare due to the absence of bison, but a few years after the pipeline was constructed, mouse-ear cress was found growing along the trenchline where soil had been disturbed. Research findings are being shared with the scientific community and within industry so minimal disturbance construction techniques and mitigation measures become a new best practice, ultimately reducing impacts to the landscape and increasing ecosystem resiliency. ENV