To celebrate Earth Day, Equinox Gold is highlighting some of the projects underway at our Los Filos mine complex that support the preservation of biodiversity and environmental remediation.
Environmental Remediation Program
Since 2016 more than 100 hectares of waste rock piles on the mine site have been hydro seeded, reforested and protected against rain and wind erosion. Various techniques have been applied including contouring of slopes, constructing water diversion channels and placing biodegradable materials such as coconut mesh on the slopes to provide a stable surface for regrowth. These techniques have resulted in the successful growth of new vegetation and many species of insects, birds, mammals, and reptiles have established themselves in the remediated areas.
Agricultural Pilot Project
In 2018, Los Filos began operating an agricultural pilot project on a reclaimed heap leach pad to remediate the soil and improve growing conditions. The project focused on three techniques to restore organic content in the soil: 1) reincorporation into the soil of the fodder generated at the end of the harvest, 2) crop rotation, and 3) reduced tillage. Soil testing after one year demonstrated increased biomass and soil quality adequate to grow food-safe crops. In 2022 the project will be scaled up to cover one hectare of land with multiple crop rotations to demonstrate the feasibility of soil regeneration using these methods.
In 2022 Los Filos began implementing a polyculture agroforestry system to achieve three objectives: 1) soil regeneration, 2) capturing CO2, and 3) the development of alternate sources of livestock feed.
Different varieties of agave will be intercropped with companion trees, such as mesquites or acacias, that fix nitrogen to the soil. Carrying out scheduled rotation of grazing animals in the grasslands of the project will improve soil quality by eliminating invasive species and dead grasses, facilitating water filtration, and concentrating manure, increasing organic matter in the soil and overall soil fertility. In addition, the agaves and companion trees will sequester significant amounts of carbon dioxide and the agave leaves can be harvested.
Agave produces large amounts of biomass in its leaves and far exceeds the harvest of any other crop in the area, but does not require irrigation or the use of chemicals. Up to 100 tonnes of agave can be harvested per hectare per year. Maguey, a member of the agave family, can be fermented either alone or mixed with high protein bean pods from the companion acacia trees and used at livestock feed during the dry season.