Grosvenor Subsidence Impact Assessment

This project, carried out for Anglo American’s Grosvenor Coal Mine, assessed the impact of subsidence on native vegetation.  

Verterra carried out baseline assessment by detailed statistical analysis of spatial imagery and subsequent time-series monitoring of vegetation health to inform management decisions regarding larger-scale interventions.

The project involved development of a rolling program for assessment, monitoring and assessment of spoil stockpiles and subsidence panels (inundation panels).

Initial assessment of 9.75ha of Endangered Remnant Vegetation (RE 11.3.1) was undertaken using a UAV platform with a visible colour (Red, Green, Blue (RGB) and multispectral camera (green, red, red edge, near infrared) payload.

Imaged areas incorporated a subsided area with varying exposure to inundation and an adjacent control area at the natural land surface.

Analysis of captured RGB (visible) images and vegetation indices constructed from multispectral imagery enabled stratification of the area into a number of inundation/disturbance classes as well as identification of previously cleared areas (not related to subsidence or inundation).