Oil and gas site reclamation takes hands-on approach

A native forb called paintbrush is often found in disturbed areas and is thus a reasonable candidate for early reclamation. — Photo courtesy Northern Alberta Institute of Technology

Dr. Amanda Schoonmaker is leading applied research at Edmonton's Northern Alberta Institute of Technology (NAIT) that will return thousands of former oil and gas well sites to their natural state.

Schoonmaker took on the role as NSERC industrial research chair for Colleges in Boreal Reclamation and Reforestation early in July. NSERC—the Natural Sciences and Engineering Research Council of Canada—is partially funding Schoonmaker's position.

Dr. Amanda Schoonmaker's work will assist oil and gas companies with provincially regulated reclamation of well sites. — Photo courtesy Northern Alberta Institute of Technology

She studied forest sciences at the University of British Columbia in 2006 and earned her PhD in forest biology and management from the University of Alberta seven years later. In 2011, she joined the NAIT Boreal Research Institute as a reclamation field research co-ordinator.

Regulation requires oil and gas companies in Alberta to reclaim well sites that have reached the end of their lifespan. The sites must meet or exceed criteria set by the provincial government including establishment of woody trees and shrubs compatible with the surrounding environment.

The regulation was first described in 2007 and more specifically defined in 2010. Part 6 of the Environmental Protection and Enhancement Act requires all specified land to be reclaimed and for companies to obtain an Upstream Oil and Gas Reclamation certificate. Older historical sites may not have to be restored to the same condition as newer sites, and mine sites have different regulations altogether, she said.

“This is a significant change,” said Schoonmaker. “(Sites were) normally seeded with grasses and the basic soil function was restored, and they left it at that."

According to the Alberta government, between 1963 and 2012, there were approximately 100,000 reclaimed and exempt wells in Alberta, 150,000 that were abandoned and not reclaimed, and nearly 400,000 drilled, but neither abandoned nor reclaimed.

Schoonmaker’s hands-on research will eventually be handed over to oil and gas companies, forest product companies, and other small- to mid-size companies committed to reclamation work.

The work includes testing methods of soil adjustment and preparation, developing appropriate sequencing of vegetation management options, and testing suitability of herbaceous cover crops and the use of woody species.

Specifically, said Schoonmaker, her team’s work focuses on oil and gas reclamation on upland sites that were previously upland forests.

“My field is bringing back commercial forests,” she said. “That includes well site reclamation and linear disturbances, sump sites, oral pits—anything that would be associated with the oil and gas footprint.”

The team is using trees and shrubs, or some combination thereof, to plant and prepare soil that has had its topsoil stripped and that has been piled for many years.

“Well sites and areas outside the mine—open pit mining is an entirely different kind of disturbance—generally have proximity to natural forests, which have seeds growing into the sites,” said Schoonmaker. “In principle, if you could prepare a site well and don’t have aggressive agronomic species, natural regeneration should roll over in time.”

Kickstarting regeneration is easier with certain species, such as green alders and poplars, for instance, which tend to populate naturally and quickly after an intense disturbance.

One recently completed trial involves a native forb called paintbrush (formerly called Indian paintbrush), which is often found in disturbed areas and is thus a reasonable candidate for early reclamation.

“We direct-seeded it onto a number of reclaimed sites, borrow pits mostly,” said Schoonmaker. “It did quite well.”

In another trial earlier this year, the team "hitchhiked" a native herbaceous species (showy aster or fireweed) with a nursery-produced white spruce seedling by growing both in the same plug.

“The idea here is to encourage a wider diversity of native plants on-site as well as potentially providing protection and cover for white spruce during initial establishment,” she said.

The time it takes to regenerate a site can vary. “If there is contamination, we have to deal with the soils and haul material out,” she said. “On minimal disturbance sites, such as an exploration site, we could see a site certified in two or three years.

“Certification is typically more like eight to 10 years, but if you deal with the site properly from the outset, it can be good in as few as five years.”

Oil and gas site owners can take pre-emptive measures to make site reclamation easier at the end of the well’s life.

A weed management program will keep the weed bank down and help with the final reclamation, and decompacting the soil once it is no longer in use will create a good, rough surface, which facilitates the reseeding process.

“Smooth is not good,” said Schoonmaker. “Incorporating certain woody materials will also help kickstart the regeneration process.”

In northwestern Alberta, there exists the challenge of managing the weed population that results from sites’ proximity to agricultural sites where some weeds have become naturalized and spread, hindering reforestation.

An example is sweet clover, a non-native agricultural species that is now common in disturbed areas. Ridding the area of invasive species without harming the new growth can be tricky.

“We can’t spray it because we are trying to regrow other things,” she said. “It is a forest management challenge to look at what other tools we need to employ to manage undesirable vegetation versus desirable forest species.”

Schoonmaker’s current research contract is five years, with a renewable option. “As we make steps towards finding tools and alternatives, we will find some work well and some won’t,” she said. “We will have to ask ‘why not?’ and bring more tools that fuel new research.”

Sharing the information is an ongoing process—once results come in, the scientific findings are published in short, practitioner-focused, how-to technical notes on the program’s website. The team also attends and disseminates information at industry workshops and seminars, hoping to both share information and garner feedback on what techniques have worked and what challenges have arisen.

Besides its practical application and benefit, Schoonmaker’s work at NAIT offers opportunities to transfer the technology and education to future environmental scientists working in the oil and gas fields.

“We hire students out of NAIT who would be going into the environmental reclamation field in the future,” she said. “It is an important way we translate our results into the industry and transfer knowledge into the field. We are training the next generation of practitioners and that is an important component of this work.”