Our monitoring program covers every possible point of impact by the mine and is audited by independent scientists.

We have a comprehensive range of programs that meet government regulations and are designed to evaluate the mine’s performance. Results from these programs are used to improve environmental management strategies and identify any emerging or potential impacts.

Monitoring results are compared against baseline information from as early as 1992, national guidelines for water and soil quality set by the Australia and New Zealand Environment and Conservation Council (ANZECC), and the National Environment Protection Measures (NEPM).

For the results of all monitoring programs, see the Xstrata Zinc Australia Sustainability Report and the Memorandum newsletter.

Other areas of interest

Xstrata Zinc Australia Sustainability Report 2010

Mine site monitoring

Routine sampling of the mine water management system identifies all sources of contaminants and risks, helps improve water management and recycling and also contributes to future planning.

The mine water monitoring program includes testing:

• water levels in all key mine water storage facilities to check runoff rates and water losses
• water meters on all major pipelines used to transfer water within the mine’s system including supplying recycled water to the process plant and water trucks
• water use to make sure all opportunities are taken to reuse mine water
• potable water quality based on Australia Drinking Water Guidelines 2004
• surface water quality in Barney Creek, Surprise Creek and McArthur River
• groundwater quality and levels via monitoring bores installed around the mine site.

Tailings system monitoring

The tailings storage facility and pipeline are regularly subjected to an extensive range of tests to check the content of the tailings, assess any incidence of seepage and to make sure the embankment wall, pipe and all infrastructure are in good working order. These tests are summarised in the following table.

MONITORING SCOPE	SCOPE	FREQUENCY	TESTING PARAMETERS
Tailings	Sampling	Monthly	Oxidation characteristics
Piezometric levels	Monitoring bores	Every two months	Water depth and pressure
Surface water management	Inspection Photographic records	Weekly	Erosion and sedimentation
Groundwater	Observation bores downstream of recovery bores	Every two months	Water quality Total volume of water pumped from recovery bores
Water quality	Samples from sediment ponds, Surprise Creek, Barney Creek tributary	Monthly when water present After significant rainfall events	Water quality
Decant pond	Inspection of water level and samples	Daily for levels Monthly for quality	Depth Water quality
Embankment	Inspect condition	Monthly	Surface expression of seepage Erosion

Erosion and sediment control

This monitoring aims to ensure the bund walls around the open pit are secure and includes:

• Visual observation of the bund walls to identify any cracking or gully erosion and of the topsoil stockpiles to check for wind and water erosion
• Inspection of sediment traps weekly during the wet season and monthly during the dry season and after all intense rainfall events.

River rechannelling – erosion and sediment monitoring

The long-term monitoring of the Barney Creek and McArthur River channels is important to check their stability. Vegetation abundance and diversity will be based on species highlighted through previous baseline surveys prior to rechanneling.

Results are checked against annually taken photographic reference sites, aerial photographs and detailed cross-section surveys and analysis.

Rechannelling rehabilitation

The effectiveness of revegetation works as well as the extent of natural regeneration is checked as the new ecosystem develops. The monitoring checks for rock movement, erosion, soil accumulation, the progress and numbers of tube stock planted, success of seed regeneration, weeds and plant growth. This is undertaken by Charles Darwin University.

Fish monitoring

The fish monitoring program compares if the types of fish found in the natural sections of the McArthur River are at the same time, also present in the new diversion channel. These include the freshwater sawfish. Benchmarks were set through a sampling program from a number of sites along the river.

This monitoring covers fish populations, seasonal pools, tests to check for heavy metals in fish, mussels or crustaceans, and a tagging program to track fish movements.

A specific action plan has also been developed for the freshwater sawfish taking into consideration:

• the ecology and biology of the freshwater sawfish
• the existing environment and the potential impacts from the new river channel
• management actions to maintain freshwater sawfish populations in the long term
• actions in case a fish becomes trapped in the new river channel
• ongoing monitoring of the freshwater sawfish populations for the life of the mine
• a community awareness and education program.

Bird monitoring

This program checks for any changes in the population of birds in the area surrounding the mine both upstream and downstream. Data collected is compared with other local sites which have not been disturbed by mining activities. The banding of birds is also taking place on indicator species like the purple crowned fairy wren and buff sided robin.

At the mouth of the McArthur River, a migratory bird program also takes place as required under the Commonwealth Government’s approval.

Dust and soil

Monthly dust and annual soil samples are taken from sites around both the mine and Bing Bong loading facility. These check for any potential contamination from dust generated by the operations. Special dust fallout gauges are set up around the sites to check for zinc and lead. Soil samples are taken annually at the same locations and are checked for zinc, lead, cadmium and copper.

Marine monitoring

Our annual marine monitoring program tests the quality of seawater, seagrass, sediment, oysters, and two common varieties of mollusc and compares results with benchmarks set in 1992 and 1993.

In 2007, the nine existing sites for sampling were extended to include five sites around the Sir Edward Pellew Islands for testing oysters, seagrass, seawater and molluscs. The advice of local community members was sought in determining the new locations.

In addition to the annual series of monitoring, MRM has commissioned specific studies on:

• seagrass studies within the swing basin for the Bing Bong loading facility to track the recovery of seagrass beds after their destruction by cyclones in 2000
• dredging monitoring of the navigation channel to check for impact on seagrass populations and turbidity
• water quality within the navigation channel and swing basin.