Environmental Performance

Kwinana Nickel Refinery recorded two new Level 2 environmental non-compliances, and eight Level 1 non-compliances for 2004. View 2004 environmental non-compliance incidents for KNR.

The first Level 2 incident involved the release of a vetrocoke solution within the refinery. Vetrocoke is a solution containing potassium carbonate (~22%), glycine (~3%) and arsenic (~2%) The solution was released during recommissioning of the hydrogen plant following maintenance, vetrocoke solution was carried over into the vent system. Wind carried solution over the roadways and plant areas. A number of people on-site were exposed to this material, however no adverse health impacts were recorded. A sampling program was undertaken to determine the extent of contamination on-site and affected areas were remediated accordingly.

The second Level 2 incident involved a leak from an underground pipeline, used to pump an ammonium sulphate process solution from the refinery to Baldivis. Approximately 80 to 100 kilolitres of liquid, which had pooled on the surface, was recovered and transferred back to the Baldivis facility. Subsequent investigation also confirmed a small contamination plume in the groundwater beneath the spill site. A recovery bore has been installed and intermittent pumping will be carried out until the plume has been satisfactorily recovered. Recovery of contaminated solution is currently estimated to be achieved by June 2005.

Investigations revealed that the leak was due to that section of the pipeline having initially been laid on top of a small limestone outcrop, combined with years of vibration from vehicle movements on the adjacent roadway forcing the pipe down onto a pointed limestone rock, which eventually pierced the pipe. The pipeline has been repaired, additional leak detection systems installed and an on-going inspection program, including periodic pressure-testing, has been put in place to prevent a reoccurrence.

Vegetation monitoring was carried out following the event, to determine the impact of the release on vegetation. Trees within 10 to 20m of the spill location have shown a decline in condition. Previous localised spillage of effluent in similar circumstances has led to similar declines in nearby trees and in many instances the tree species recovered. A six-monthly ongoing vegetation-monitoring program has been put in place.

Six of the Level 1 incidents related to community complaints, regarding previously unrecorded odour events. The release of H₂S gas has been identified as a potential source of odour problems. A number of measures have been put in place to reduce the frequency and severity of H₂S releases, including improved plant control, automatic shut-down systems linked to area monitors and improvements to venting systems. In addition, it is planned to completely replace the existing H₂S plant in 2006. The emission control and destruction technology incorporated into the new plant will further reduce the risk and severity of emissions.

The remaining two Level 1 non-compliances involved minor spills of process liquors, which were immediately cleaned up.

An update on the progress of groundwater recovery/remediation associated with the outstanding Level 4 incident, relating to groundwater contamination at Baldivis, and outstanding Level 3 incident, relating to groundwater contamination at the refinery, is provided in the Land Management and Biodiversity section.

Resource Use

Annual environmental targets established for total water use, energy use, land rehabilitation earthworks, land rehabilitation, revegetation and sulphur dioxide recovery were all met. The high quality water use target was not met.

Contaminated groundwater recovered from Kwinana Nickel Refinery and Baldivis is treated and then recycled within the process plant. During 2004 we commenced plant modifications to increase the capacity of the treatment plant from 1,600 lpm to 2,300 lpm. These modifications will be complete by March 2005 and will result in a corresponding reduction in potable water consumption.

Land Management and Biodiversity

Refinery

Kwinana Nickel Refinery is located 800 metres from Cockburn Sound, a major aquatic recreational area and fishery. Careful management of these competing interests will ensure the sustainability of these activities at Cockburn Sound.

Groundwater contamination, if not managed effectively, has the potential to impact on Cockburn Sound. The history of the site has borne this out; in 1993 Cockburn Sound was impacted by some 1105 tonnes/annum of ammonium sulphate from historical groundwater contamination arising from Kwinana Nickel Refinery's activities. Since then impact from the site has been reduced to approximately three tonnes/annum (from residual contaminants in groundwater). This has been achieved by:

1. Completion of civil remedial works at a cost of $8.4M in 1994 - 1996
2. Installation of groundwater recovery infrastructure from December 1995 at a cost of $21M.
3. Undertaking an intensive contaminated groundwater recovery program from beneath the Kwinana Nickel Refinery site. The Department of Environment signed off this project having achieved effective completion in June 2001.
4. Ongoing groundwater monitoring of the Kwinana Nickel Refinery site
5. Changes to work practices and an ongoing spill awareness and education program.

A previously undetected plume of arsenic groundwater contamination was identified in 2003. The plume extends over an area of 2000 square metres and is fully contained within the site boundary. It is estimated to contain 1,500 kilograms of arsenic.

Investigations into the source of the plume revealed its origin as an historical spillage of vetrocoke solution - an arsenic-based process reagent. Spillage is believed to have pre-dated major process containment initiatives across the site which were completed in 1996 and significant changes to work practices around that time.

As part of long term recovery plan a recovery bore was installed and has been operating since July 2003. Investigations indicate that it will take three to six years to recover the plume.

Baldivis

The redundant Baldivis Tailings Storage Facility was used to store solid tailings residue until 1985 and liquid tailings residue until 1995. The facility was capped in 1997 as part of its decommissioning plan. The facility is located 1000m from Lake Cooloongup, a seasonal saline lake supporting various bird species and surrounded by stands of Tuart trees. Lake Cooloongup and the surrounding area are an A Class reserve administered by the Department of Conservation and Land Management. Commercial market gardens that utilise groundwater for irrigation purposes are located within close proximity to the facility.

Groundwater contamination in the area surrounding Baldivis Tailings Storage Facility was identified in 1979. A government approved program for management of the area was subsequently developed and groundwater recovery started in 2001, following completion of groundwater recovery from the Kwinana Nickel Refinery site. Since 2001, a total of 1510 tonnes of ammonium sulphate was recovered.

Contaminated groundwater clean-up at Baldivis remains on schedule for completion in 2010.

Annual monitoring of the impact of the groundwater contamination on vegetation is undertaken in the area surrounding the Baldivis facility. Monitoring indicates that the area is subject to regular bushfires that have resulted in very dynamic changes in the number of trees and shrubs and the condition of the respective species. Generally, the impact of fires has exceeded the impacts of the ammonium sulphate leakages from either the Baldivis Tailings Pond (prior to decommissioning) or from localised pipeline leakages.

Monitoring studies completed by CSIRO have shown that the environmental impact on the lake system is minimal. It would appear that macroalgae within the lake system are mitigating the impact of the increased nitrogen input from the contaminated groundwater.

Air Emissions

The refinery's most significant air emissions are ammonia, at an estimated 750 tonnes per annum (tpa), and methane, at an estimated 460 tpa.

There are two main sources of ammonia emissions: the Tail Gas Scrubber and the Reduction Flash Tanks. Neither of these systems readily lend themselves to improvement programs, however work will be undertaken in 2005 to identify opportunities for improvement.

Methane emissions primarily arise from a gas-scrubbing process to remove residual methane from hydrogen gas, which we manufacture on-site. A flare was installed and commissioned in April 2003 to destroy waste gas from this process, this has resulted in a 550% reduction in the 2003 methane emissions - from 2,500 tpa to 460 tpa.

A noise monitoring station is maintained by the site and is located some 500m off-site between the refinery and the local community at Rockingham to the south. Data from this station cannot differentiate between general noise output from the Kwinana Nickel Refinery site and other local industries, however it can be used to determine the impact on the community of any incidents involving increased noise emissions from the Refinery. Data from the station is provided to the Department of Environment.

The Kwinana Industry Council manages an ambient sulphur dioxide emissions monitoring program on behalf of a number of local industries, including KNR. Recorded levels of sulphur dioxide are consistently well below the regulatory limit.

Waste Management

Following cessation of tailings slurry disposal to the Baldivis site in 1986, residue from the leaching process has been processed into a solid form for removal from the site. This material contains valuable concentrations of metals, but, historically, a cost-effective recovery option was not available. The residue was stored at the WMC Kambalda Nickel Concentrator site between 1986 and 2002. In 2002 an agreement was reached with Minara Resources for the purchase of the residue for processing at its operations at Murrin Murrin. As a result over 13000 tonnes were transported to Murrin Murrin for processing during 2004.

Waste oil generated from maintenance activities is collected for off-site recycling. General waste is disposed at the local Rockingham landfill. Paper, cardboard and scrap metal are segregated and recycled.

Stormwater from nickel processing areas is captured and recycled back through the plant; grey water is disposed via in-ground septic systems, from which solid residues are periodically pumped out and disposed of off-site via licensed facilities.

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