How We Ensure Durable Carbon Sequestration in the Northern Great Plains


When developing soil carbon sequestration projects, a key question is: How do we ensure that the tonnes of carbon sequestered in the soil actually stay there? Soil carbon sequestration is a mechanism within a dynamic system of ecosystem processes and human decision-making – it is not as straightforward as, say, a MWh of solar energy generated. In our Northern Great Plains Regenerative Grazing Project, it is new ranching management practices – increasing rotations through smaller pastures – that regenerate grasses and sequester carbon in the soil. The question arises: what happens if a rancher stops implementing those practices, or sells their ranch to a new farmer who plans to till the soil and begin growing cash crops? What if a rancher participant operating on leased land loses their lease and can no longer implement the practice there? These potential scenarios create the risk of a “reversal,” meaning  carbon sequestered that has been verified has been released back into the air, negating its benefit. Reversal risk is a part of all soil carbon sequestration projects that must be effectively mitigated. We manage reversal risks associated with our project through project activity design, long-term agreements, and buffer pools. 


First, when designing projects for land managers, we only want to encourage activities that will improve financial and business outcomes for the long-haul. The project activity here – planned, high-density rotational grazing – when done right, increases the productivity of grass, which increases the productivity of the cattle herd reliant on the grass, and creates opportunities for ranchers to even expand their herd size, and thus their assets. And not only should these practices increase productivity, but they should increase resilience to extreme weather – like droughts and floods – minimizing potential losses to soil, forage, and herd health.  By helping ranchers adopt a practice that is not just good for the climate but good for business long-term, we are ensuring durability of carbon in the soil for the long-haul. 


Second, we sign long-term agreements with both the current land operators and the landowners (which are sometimes one and the same). Land operators sign 20 year agreements to maintain rotational grazing practices, and we commit to pay them for the outcomes associated with those practices for 20 years. Landowners sign 30 year statements of public intent, filed with their land records, to keep the project area as grassland (meaning, not tilling up the soil to grow cash crops). Thus, even if the land operator changes, the landowner’s public commitment remains, and the new land operator is expected to maintain the project area as grassland.


Finally – to completely cover our bases for unforeseen situations – we manage reversal risk potential through maintaining buffer pools, e.g. holding a certain number of credits aside, unsold, should there be a need to replace a reversed tonne of carbon. We manage two types of buffer pools for this project. First, we conduct a non-permanence risk analysis following Verra requirements to determine a contribution to Verra’s Agriculture, Forestry, and Other Land Use (AFOLU) buffer pool. Verra then uses the AFOLU buffer to fill gaps created by any AFOLU project types that have reversals caused by unintended outcomes, such as fires or drought. Based on the scoring of our non-permanence risk assessment, we make a deduction from the total number of issued credits, which is set aside in the Verra buffer pool to protect against any reversals of credits in the future. We conduct these risk analyses and buffer deductions during each verification; we analyze each participating ranch based on its context and risk level, including its lease arrangements, and make an associated credit deduction and contribution to the Verra buffer pool. Secondly, Native manages an additional buffer pool for any potential “intentional reversals,” such as a rancher choosing to till up their enrolled grasslands or develop them for other purposes. For this buffer pool, we set aside 15% of the credits that we forecast the project will produce.