Solid waste by destination
This year our sites generated 7,630 tonnes of solid waste, 74 percent less than last year. This reduction is due to the inclusion of 6,700 tonnes of soil and pond settlings in last year's total amount, which was removed during capital project work at our Cheyenne site in Wyoming USA, and to increased recycling. Approximately 4 percent of our solid waste is classified as hazardous and is mostly waste from the manufacture of our explosives products. In addition 1,456,604 tonnes of ammonium nitrate that was unsuitable for use in explosives manufacturing was converted to fertiliser at several of our sites. This was sold to local farmers as either a nitrogen rich liquid fertiliser, or a low grade solid fertiliser.
Solid chemical waste
Our sites generated 2,177,466 tonnes of solid chemical waste this year. Over 99 percent of this was phosphogypsum chemical waste that was stockpiled at our site in Phosphate Hill, Queensland, Australia. This waste is considered hazardous because of its low pH, however water and phosphate are currently being reclaimed from this material and it is planned that these stockpiles will ultimately be capped and re-vegetated. The other 324 tonnes (0.01 percent) of hazardous chemical waste was mostly generated by our North American explosives initiation system manufacturing plants. This year 48 percent more solid chemical waste was generated. This is directly due to two maintenance shut downs: the first was at our Phosphate Hill site last year, which reduced production time, and therefore phosphogypsum waste for last year’s reporting period; and the second was at our Mt Isa site this year, which involved the removal of large volumes of chemical wastes as part of maintenance work.
Liquid waste by destination
Our sites generated 15,151 kL of liquid waste that was sent offsite for re-use, recycling or disposal this year. This includes 12,907 kL of contaminated water, 3,597 kL of hazardous liquid waste and 741 kL of non-hazardous waste. Approximately 54 percent of this waste is nitrogen-rich water from our fertiliser manufacturing and distribution sites in Australia that is sent offsite to third parties for use as fertiliser and/or woodchip additive. 40 percent of the hazardous waste was septic liquid or sludge (considered a bio-hazard) which was sent offsite for disposal or treatment. The increase in hazardous liquid waste this year is due to an increase in septic waste at one of our manufacturing sites in the USA.
Waste reduction initiatives
Continuous improvement in reducing all types of waste and increasing recycling has resulted in several new initiatives. Examples include:
• At Moranbah, Australia, the installation of atomising spray nozzles on evaporation ponds increased evaporation rates, reducing liquid waste water volumes
• The installation of a Cast Booster wastewater recycle system is being investigated at our Carthage, USA site. This will divert 1,368 kL of waste water per year into the making of nitric acid.
• The cleaning and on-site re-use of supplier cardboard box packaging at our Dinamita, Mexico site.
• The Research and Development (R&D) team in the USA has successfully developed methods to treat different types of wastewater for reuse in explosives emulsions manufacture and also assisted the explosives business to recycle over 2,000 t of chemical waste into making new emulsions.