Orica provides further information on ammonia emissions from Kooragang Island

15 November 2011

Orica is today providing further information in relation to an emission of ammonia vapour from its Kooragang Island site on Wednesday 9 November 2011.

As previously advised, last Wednesday, the No.1 Ammonia Feed Tank attached to the No.1 Nitric Acid Plant at the site experienced increases in internal pressure which triggered the opening of its relief valve. The opening of the relief valve is part of the safety mechanisms put in place to ensure there is no excessive pressure within the tank. The ammonia released through the relief valve was vented through a tall stack. As ammonia vapour is lighter than air, under normal operations, the height of the stack facilitates dissipation of the ammonia vapour into the atmosphere.

Orica believes that the ambient atmospheric conditions last Wednesday were such that some ammonia vapour drifted to ground at the Australian Rail Track Corporation facility in nearby Mayfield.

Initial estimates of the quantity of ammonia vapour released were provided to NSW Fire and Rescue on 9 November by Orica based on 'worst case scenario' calculations. Upon refining the calculations using the actual conditions at the time and more information as it has become available, Orica can advise that the actual amount of ammonia released during the incident was up to 170 kg, not the 875 kg originally advised.

Orica would like to provide some context to the figures reported over the weekend relating to ammonia emissions.

Industry is required to report emissions to the National Pollution Inventory (NPI) on an annual basis under the NSW Government's Protection of the Environment Operations (General) Regulation 2009. Where specific emissions are not measured at a site level, the NPI provides Emission Estimation Technique Manuals. Using these manuals, companies such as Orica estimate their fugitive emissions for

substances such as ammonia. The Company believes these estimates to be conservative. In 2009/2010, Orica calculated fugitive ammonia emissions of 69,000 kg.

Orica's ammonia plant at Kooragang Island produces 15 percent of Australia's ammonia and the emissions to air during 2009/2010 from the entire facility constituted 0.5* percent of Australia's total ammonia emissions to air.

Overall, Orica's Kooragang Island site is 33rd on the list of facilities emitting ammonia to air nationally. This information is publicly available on the National Pollution Inventory website. Orica continues to work towards reducing its emissions through ongoing maintenance and capital expenditure in conjunction with process and operational improvements.

The Kooragang Island ammonia plant supplies ammonia to a range of customers as well as using it in the production of ammonium nitrate on site. The plant produces carbon dioxide (CO2) which is used in the medical and food and beverage industries. In addition, aqueous ammonia is manufactured for use in water purification. Orica's ammonia plant has been shut down since 8 August 2011 and is not currently providing CO2 to its customers.

The ammonium nitrate plant was shut down by Orica on the evening of 9 November in response to the ammonia discharge. The ammonium nitrate plant supplies over 50 percent of the mining explosive requirements in the NSW Hunter Valley. Orica is currently working to source alternative supplies of ammonium nitrate for its customers to keep disruption to a minimum.

Orica will be conducting the fourth in a series of Community Information Sessions on Thursday 17 November from 3.30 - 5.00 pm at the Stockton RSL Club and from 7 - 8.30 pm at the Stockton Surf Life Saving Club.

Media contact: Nicole Ekert, Communications Manager,

Tel: (03) 9665 7538

Mobile: 0407 166 783


* Based on Orica’s ammonia emissions to air divided by the total ammonia emissions to air from all sources (by source) (National Pollution Inventory)