Water monitoring

ERA has an extensive water monitoring system which tracks changes in composition and flow rates in surface water, ground water and waterways.

This system includes 200 ground water monitoring bores and 13 realtime monitoring points in waterways upstream and downstream of the Ranger mine.

Real-time water quality results from ERA's in-stream monitoring points in Magela Creek confirmed improvements to water quality in 2011 due to diversion and control of ore stockpilerun-off and catchment improvements completed in 2010.

The construction of a stockpile interception trench and catchment improvements to manage water run-off from stockpiles combined with high inflows of high quality water treatment plant permeate has improved water quality in Retention Pond 1, which flows to Magela Creek.

The levels of electrical conductivity, a measure of dissolved salts, calcium, magnesium and sulphate concentrations in Retention Pond 1 all show a significant reduction compared with previous years.

The Supervising Scientist Division (SSD) also conducts independent monitoring of waters upstream and downstream from the mine site. These results are published on the SSD website.