PERTH (miningweekly.com) - The Western Australian government has lifted the suspension on lead exports from the port of Geraldton to enable a trial shipment, following results of health testing and improvements to operations, infrastructure and monitoring.

During December last year, Transport Minister Troy Buswell took the precautionary measure to suspend the shipment of high precious metals (HPM), which comprise between 30% and 40% lead sulphide, after one of the port’s monitoring stations detected an exceedance of the allowable lead level set as part of the port’s licence conditions during one of MMG Golden Grove’s shipments.

MMG, which is owned by Hong Kong-listed Minmetals, immediately deferred shipments of HPM concentrate and began working with the Geraldton Port Authority (GPA) and the relevant government departments to better understand the dust emissions from the metal concentrate loading.

Buswell said on Monday that a trial shipment had now been approved, following the results of the health testing, improvements to operations, infrastructure and monitoring at Geraldton port, as well as the Department of Environment and Conservation and the Department of Health’s reassessment of realistic, safe targets in the port’s licence conditions.

“While I was provided initial advice that the exceedance posed no threat to health, the decision to suspend the trade of this product was made on the basis that the state government’s primary concern in this instance was for the health of the people of Geraldton,” he said.

Buswell said that even once the state government received confirmation that the community’s health had not been put at risk, he was not prepared for lead shipments to restart until the government could be satisfied the risk of further breaches of environmental guidelines were mitigated through the implementation of better procedures and structural improvement.

“I am now satisfied that several improvements have been undertaken to enable the trial, including the tightening of wind restrictions, the introduction of loading limits and the purchase of new compliance equipment.”

The Minister said the trial would occur under a number of conditions, including the strict adherence with Geraldton port’s amended loading procedures, the establishment of a monthly data analysis meeting between the GPA and MMG to monitor results, and a 24/7 supervision of all HPM ship loading operations by an appropriately experienced MMG representative.

Buswell said MMG commissioned adjunct professor Dr Roger Drew of Toxikos Toxicology, to conduct an independent scientific-based investigation into the community health risks of lead and the suitability of the existing lead licence limit criteria.

“Following consideration of Professor Drew’s report, which was finalised in May 2011, the Department of Environment and Conservation, in consultation with the Department of Health, amended the Geraldton port’s Environmental Licence on September 8, 2011 to a more realistic, yet safe, standard,” he said.

The threshold has been amended from 0.5 µg/m³ limit over 24 hours to 0.5 µg/m³ limit on a three-month rolling average. In addition, two 24 hour lead targets have been included in the licence. A target of 2 µg/m³ will apply to the Berth 6 (seaward) monitor only. For all other monitors adjacent to the City of Geraldton, the target is 0.5 µg/m³.

The Minister said a second trial shipment of HPM would only be approved subject to an acceptable outcome for the first trial.

Resumption of bulk loading of HPM will only be approved subject to acceptable results for the first two shipments and to ongoing monitoring and performance outcomes acceptable to Geraldton port.

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