Summer Hills Soil Carbon Project

The Summer Hills Soil Carbon Project is a soil carbon sequestration initiative located approximately 20 kilometers north-east of Wallumbilla and 50 kilometers east of Roma in the Maranoa region of Queensland. Registered on October 30, 2024, the project covers a land area of 1,128.91 hectares. The region is predominantly utilized for mixed farming, specifically cattle grazing and broadacre cropping (such as wheat and sorghum), alongside significant natural gas extraction activities within the Surat Basin.

This project operates under the 2021 Soil Carbon methodology (Estimation of Soil Organic Carbon Sequestration using Measurement and Models). This method involves establishing a baseline of soil organic carbon (SOC) through physical soil sampling and then implementing land management changes designed to increase SOC levels over time. Credits are issued based on the measured increase in carbon stocks, often verified by a combination of physical measurement and modeling tools.

The environment in the Maranoa district is classified as semi-arid to subtropical, with average annual rainfall ranging between 550mm and 600mm. The soil composition in this area typically features the cracking clay soils (Vertosols) and texture-contrast soils (Chromosols) characteristic of the Brigalow Belt, which are naturally fertile but require careful management to prevent degradation.

Project activities include altering stocking rates to manage grazing intensity, pasture cropping, and the introduction of legumes to improve soil health and vegetation cover. The proponent, Santos Limited, is a major Australian energy company. This project is part of Santos's broader "nature-based solutions" portfolio, designed to generate Australian Carbon Credit Units (ACCUs) to offset emissions from their GLNG upstream gas operations, effectively layering carbon farming on top of existing land holdings.