Tailings and Impoundments Reflectance Index (TIRI)

The Tailings and Impoundments Reflectance Index (TIRI) is a remote monitoring service from AssetAssurance Monitoring (AAM LLC) for tailings storage facilities (TSFs) and mine-site impoundments, covering abandoned, legacy and operating sites. Tailings and impoundments need regular, full-time awareness, and each site's Trigger Action Response Plans (TARPs) set limits on the extent of open water (the supernatant pond), beach and dispersed solids deposits.

TIRI is computed from Sentinel-2 and Landsat imagery. The customer supplies the facility outline as a KML or shapefile, and AAM configures the dates, analytics and outputs for each site. Every scene is acquired, cloudy or not, and cloud-covered acquisitions are kept as part of the weekly record. Each TSF surface is classified into zones (decant and supernatant ponding, dispersed solids, beach), so that differences in areal deposition can be tracked from one acquisition to the next. A historical review of one to two or three to five years can be added. AAM's published examples include a retrospective of Córrego do Feijão Dam 1 before its January 2019 failure and a before-and-after review of the 2014 Mount Polley event using Landsat data.

Results are delivered through a secure Power BI dashboard built with partner GeoTerra Image, an online portal, emails on each new acquisition and PDF reports. TIRI data can also be combined with InSAR or in-situ measurements. Prices are quoted per request, based on the number and size of the TSFs and the length of historical review, with annual subscriptions available.