ISO 14001 certification

In February 2005, Olympic Dam achieved ISO 14001 certification for the environmental aspects of the Olympic Dam Operations. The area covered includes the Special Mine Lease, associated borefields and the aerodrome.

To qualify for this standard an accredited certification body performed a baseline review in February 2004, and in December 2004 they completed the certification audit of the Olympic Dam Environmental Management System against the AS/NZS ISO 14001:1996 EMS Standard. Positive feedback was received from the auditors indicating that environmental issues were generally managed well on site. The audit did identify two major non-conformances and six minor non-conformances. An action plan to address the non-conformances was developed and submitted to the auditors.

An Environmental Management System is a structured organisational system designed to achieve continuous environmental performance improvement. It provides consistency through the allocation of resources, assignment of responsibilities and ongoing evaluation of practices procedures and processes. During 2004, significant progress was made in further developing the Environmental Management System to continually improve its effectiveness. In addition to the continued implementation of detailed environmental management programs, there was also a significant effort allocated to documenting the processes and procedures used to manage environmental issues.

Revised South Australian Reporting Procedures

In 2003, the South Australian Government introduced new Criteria and Procedures for Recording and Reporting Incidents at South Australia's uranium mines. This new procedure required reporting and publicly disclosing spills of a defined volume and nature, even if they were contained within engineering structures (bunds) and/or within the process plant boundary (tertiary containment - drainage and pond system).

A proposed amendment to the incident reporting procedure was distributed in 2004. This raised the Government reporting limit to 100m³ for spills of radioactive process materials outside of secondary containment but within the plant boundary, and introducing a Government notification requirement for spills greater than 50m³ outside of secondary containment but within the processing plant boundary. Spills within the Tailings Retention System bunded areas remain reportable at volumes greater than 50m³.

Non-compliances

As reported on the WMC sustainability noticeboard, three environmental non-compliance events were recorded at Olympic Dam in 2004. All of these were Level 1 non-compliances. In 2003 there were six non-compliance events. All spilled materials were cleaned up as soon as practical following these spills. View 2004 environmental non-compliance incidents for ODO.

The first Level 1 incident related to a spill of a small amount of tails slurry. The incident occurred as a result of a rupture of a pinch valve sleeve on a tailings delivery line. Approximately 25m³ of material was released. The majority was captured in a bund surrounding the delivery line, however approximately 2m³ splashed onto adjoining sandy ground. There has been no long-term environmental impact as a result of this incident.

The second Level 1 incident involved a spill of an estimated 460m³ of process liquor within the hydrometallurgical plant. It was fully contained within the bunding network and returned to the tailings system.

The spill was caused by the failure of a high-density polyethylene pipe and did not cause environmental impact. The liquor comprised mostly copper, with a residual 0.014% uranium content.

The third Level 1 non-compliance was a spill of liquor being transferred between evaporation ponds, occurring as the result of valve failure during pump maintenance. The material was fully contained within a bund and was returned to the Tailings Retention System. There were no occupational health and safety or environmental impacts.

The amount of evaporation liquid involved was approximately 250m³. Only low concentrations of residual copper (concentration 0.12%) and uranium (0.009%) remain in the weakly acidic solution.

Outstanding non-compliance

Diesel Spills Update

As reported during 2001, three diesel leaks occurred at Olympic Dam due to two underground fuel lines and corrosion of a bulk storage tank. As a first step, we removed most of the surface contaminated soil and installed monitoring wells. We have continued to monitor the affected area and assess the environmental impact of the spills. There has been no additional leakage since the completion of engineering work around the pumps, however further treatment is required.

Saline aerosol emissions update

Electric fans, mounted on top of dedicated ventilation shafts, draw ventilation air through the underground mine at Olympic Dam. They also capture a significant amount of the saline water from the existing ground water and eject it as a salt-laden mist. The mist has previously killed salt-sensitive dune vegetation species around ventilation shafts on the mining lease. This is an issue for most underground mines developed below aquifers containing water with a high salt content. Our management of this non-compliance is detailed in our Emissions section of this report.

2003 EPA Audit

In November 2003, the South Australian Environment Protection Authority (EPA) undertook an extensive audit of the Olympic Dam Operations. WMC was advised that the audit had identified a series of minor issues associated with routine operations that it believed should be addressed. (For further detail please click here - Summary of Audit by the SA EPA on Sustainability noticeboard).

The authority required Olympic Dam to prepare an Environmental Improvement Program. Some of the issues raised were already being addressed under Olympic Dam's continuous environmental improvement activities, which are included in our Environmental Management Program - submitted annually to the South Australian government.

The audit highlighted actions concerning hydrocarbon management and aspects of spill management in the hydrometallurgical and concentrate leach facilities.

Hydrocarbons

To ensure an improvement in hydrocarbons management, 12 projects have been identified to upgrade hydrocarbons storage facilities. These projects have been prioritised and are scheduled for completion by the end of 2005. The projects are designed to ensure the facilities comply with appropriate Australian standards and EPA guidelines.

Hydromet Spill Management

In 2004, Olympic Dam performed a comprehensive environmental risk assessment of the hydrometallurgical and concentrate leach facilities, investigating issues such as maintenance and operating procedures, materials selection and pipeline design. Actions arising from this risk assessment included the replacement of existing pipelines with poly-lined steel. These pipes have improved corrosion resistance and are more durable. This has been supported by amendments to existing operating procedures.

Resource Use

Bore Drain Closure Program

The Great Artesian Basin artesian bore rehabilitation and bore drain closure programs, jointly funded by the Commonwealth and State Governments, are controlling artesian flowing bores and replacing free-flowing bore drains on pastoral properties, with reticulated poly-pipe networks.

Under the piping program, bore drain users are required to provide 20 per cent of the program material costs plus 20 per cent installation costs. WMC is funding this contribution for the material costs of pastoralists in South Australia, committing $1.2 million since 2001. An additional $1 million dollars was contributed for Stage 1 of the program.

The majority of bores received piping materials in the last two years, allowing progressive installation during 2003/2004. To date, 336km of bore drains are being replaced with pipe systems with a predicted water saving of 60ML/day once installation is completed. These savings exceed the total industrial water supply requirements of Olympic Dam's operations.

The program is nearing completion, with the remaining few bores to receive materials in 2004/2005. Bore rehabilitation work will continue during 2004/2005.

Targets - Water

Efficient use of water is a priority at Olympic Dam. We set ourselves targets to improve our water use efficiency over time. This year we did not meet our target due to an increase in water usage in the de-slimes area, where we remove coarse tailings solids from the tailings stream for use in backfill underground. The removal of coarse tailings solids requires dilution of the tailings stream with water. The additional water is normally recovered from the tailings stream, after removal of coarse tailings solids, and recycled. In 2004, additional coarse tailings solids were used underground which required additional water to be added to the tailings stream for dilution prior to removal of coarse tailings solids. The water recovery and recycle system was not able to accommodate the increased quantities of water to be recycled and therefore additional water was consumed during dilution of the tailings stream. This additional water reported in the final tailings stream after removal of coarse solids. Improvements in the water recovery and recycle system have now been completed and an improvement in water use efficiency is expected in 2005.

Land Management and Biodiversity

The Olympic Dam mine lease is 17,788.11 hectares on arid zone land.

Fauna Monitoring Program

Monitoring of several species of birds, small mammals and reptiles are used as indicators of potential impacts associated with the mine. Potential impacts include dust, gaseous emissions, localised saline aerosols or general disturbance and noise.

Various fauna monitoring has been carried out around the mine lease since 1987 with regular bioindicator monitoring developed during 1989 (Birds) and 1993 (Small vertebrates). Historically fauna indicator species monitoring has consistently recorded a localised impact from the operation, with the impact footprint rarely showing a significant change. This monitoring also adds valuable knowledge of species, both common and rare, present within the mine lease.

Each year, 45 sites are surveyed in April, July and October for all bird species present. Sites are separated into three main impact zones: mine (within 500m of the mine and process); intermediate (1km from the mine and process areas); and control (>4km from the mine and process areas).

Reptile and small mammal abundance is monitored through annual trapping surveys at 14 permanent fauna sites. These are located in four impact zones defined by possible impacts: smelter, ventilation shafts, intermediate impact and control sites.

Tailings Retention System (TRS) Bird Deterrent System

The Olympic Dam TRS is a large facility for storage of process tailings and acidic liquors which can be hazardous to fauna. The TRS can appear a likely habitat to fauna, especially water birds, due to the large quantity of liquor stored for evaporation.

In late 1996 a bird deterrent system, consisting of automated randomly fired gas guns and light beacons, was developed for the Olympic Dam TRS. This system proved effective in reducing visitation by water birds to the TRS however in late 2003 and during 2004 an increase in wildlife activity both in the region and at the TRS has been apparent. This may be attributable to increased migratory activity as a result of regional flooding of the Lake Eyre Basin in late 2003 or abnormally high rainfall in the region in 2004, or due to a decrease in the effectiveness of the bird deterrent system. An audit of the existing deterrent system was conducted in March 2004 and a number of improvement actions have been and will continue to be implemented in conjunction with a research project into better understanding the relationship between the TRS and wildlife of the area. Visit the Sustainability Noticeboard for progress on the review of the TRS.

Weed Control

An integrated weed management strategy has been developed during 2004 and agreed upon between WMC Olympic Dam, the Roxby Downs Council, Arid Recovery and the Andamooka Progress and Opal Miners Association.

The strategy targets 13 high priority weeds - which were identified through a full weed risk assessment process. Some of these weed species can be found in small infestations on the Olympic Dam mine lease and pastoral leases and in areas surrounding the Roxby Downs and Andamooka townships. As there are currently only limited infestations, prompt action provides an opportunity for a successful outcome.

While opportunistic weed control is currently underway, the progressive eradication program will start in 2005 and will be complemented by communication and education within the regional community about weed control. Weed management will not only involve removing current infestations but actively managing new weeds from entering and establishing in the region. The aim is to assist the community to identify weeds and how to manage them and encourage replacing exotic plants with native alternatives. Site environment personnel have been actively involved in the Rangelands Interim Natural Resource Management Group in developing a regional approach to introduced species management.

Use of New Technology

The Great Artesian Basin (GAB), from which Olympic Dam receives its water, has unique outflow points known as ‘Mound Springs’. The quantity of vegetated wetland associated with these springs can be directly correlated to the rate of artesian flow from a spring. The above aerial photograph (will include) demonstrates the application of integrated remote sensing and Geographic Information System (GIS) technology now being used to monitor the change in vegetated wetland area for artesian springs north of Olympic Dam. This enables us to monitor any potential impacts on these ecosystems which may be created by water extraction from the GAB. New and improved technologies, such as digital aerial photography and satellite imagery, will continue to be assessed to ensure we employ the most effective methods of environmental assessment.

Air Emissions

Saline Emissions

In late 2003, mist-eliminating grills were fitted to the ventilation shaft outlets on one of the raise bore ventilation shaft outlets. Vegetation monitoring undertaken in late 2003 and again in late 2004 indicates a greatly reduced area of impact, with significant vegetation regrowth in previously affected areas.

In addition to the installation of mist eliminators, significant rainfall over the last two years has contributed to vegetation regrowth. Investigations will continue into increasing the efficiency of the mist eliminators to ensure more effective saline aerosol capture.

Gaseous Emissions

The number of air emission events reportable to the Environment Protection Authority in 2004 was 258. This is a reduction of 33 per cent since 2001. We did not meet our ambitious emission target of 180 events in 2004. Ongoing emission reduction projects are in place and we are endeavouring to optimise our practices and procedures.

Particulate Emissions

As part of an Environment Improvement Program, commissioning of the new hydro-sonic scrubber in the slimes treatment plant (gold room) was completed in late December 2003. This has resulted in a dramatic decrease in particulate emission concentration from 500mg/Nm³ to 7mg/Nm³.

Waste Management

General Waste

A Waste Transfer Station, for the sorting of general site waste and recyclables, will be established by early 2005. General site waste includes materials such as scrap steel, cardboard and drums. This facility will enable better sorting of waste and increased recycling opportunities.

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