Environment Protection Authority v Incitec Limited
[2003] NSWLEC 381
At a glance
Source factsCourt
Land and Environment Court (NSW)
Decision date
2003-10-15
Before
McClellan CJ, Clellan J
Source
Original judgment source is linked above.
Judgment (10 paragraphs)
Introduction 1 HIS HONOUR: The defendant, Incitec Limited, pleads guilty to an offence against section 64(1) of the Protection of the Environment Operations Act 1997. The offence charged is that on or about 12 July 2002 the defendant contravened a condition of its environment protection licence by discharging waste water with a pH level below 6.2 into the north arm of the Hunter River. 2 The relevant condition of the licence was condition L3.1 which states, inter alia: "For each monitoring discharge point or utilisation area specified in the table/s below (by a point number), the concentration of a pollutant discharged at that point, or applied to that area, must not exceed the concentration limit specified for that pollutant in the table." 3 The table relevantly provided a minimum pH of 6.2. The maximum penalty for the offence in the case of a corporation is $250,000. 4 Incitec owns and operates a chemical manufacturing facility located at Greenleaf Road, Kooragang Island, near Newcastle. It manufactures ammonia, ammonium nitrate, nitric acid and granulated fertilisers at this facility. Incitec, or previous manifestations of that corporation, have manufactured those products and similar products at the premises for in the order of forty years. 5 The parties have reached agreement in relation to the relevant facts. I draw upon that agreement in making the following factual findings. 6 Incitec utilises two separate plants at the facility to make ammonium nitrate which are known by the designations "AN1" and "AN2." AN1 began operation in 1969 and AN2 commenced in 1989. 7 Ammonium nitrates are manufactured at the facility by the reaction of gaseous ammonia with liquid nitric acid. One of the items of equipment that is utilised in this process at the AN1 plant is an "acid heater" which was installed in 1993 and is used to heat nitric acid. The acid is heated by steam as it is passed through tubes that are made of stainless steel. There are seventy-six of these tubes in the acid heater. 8 After the acid is heated it is conveyed to a reactor vessel where it is combined with gaseous ammonia. The process of reacting ammonia and nitric acid generates steam. At the AN1 plant the steam produced by the reactor is condensed into a liquid form known as "condensate." This condensate is then conveyed to a tank known as the process condensate tank. The condensate which is not needed for production purposes at the AN1 plant flows out of the process condensate tank through an overflow pipe and then runs into a "spoon drain". 9 From the spoon drain the condensate enters another drain known as the "nitrate plant pit" and is then conveyed to a point in the facility's waste water system known as the "river valve pit". Various effluents streaming from the nitrate production area of the facility are combined at the river valve pit. The waste waster from the river valve pit then travels into the facility's main effluent system where it is mixed with waste water generated by the ammonia production area of the plant. This combined waste water stream is ultimately discharged into the north arm of the Hunter River by means of a multiple port diffuser. The maximum rate of flow of liquid from the process condensate tank to the spoon drain is approximately six cubic metres (six thousand litres) per hour. 10 Incitec holds environment protection licence number 828 for the Kooragang facility. Condition 1.31 identified the diffuser discharge to the north arm of the Hunter River as point one. Condition L3.2 of the licence required that the discharge from point one be maintained in the range between 6.2 and 9.5 pH at all times. 11 At all relevant times the process condensate tank has been equipped with a meter that measures the pH of the liquid in the tank. The pH measurements taken by this instrument can be read from a display that is attached to the outside of the tank. It can also be read from a panel in the room that is used to control the production processes of the AN1 and AN2 plants. The pH meter on the process condensate tank was also configured to treat audible and visual alarms on a panel in the nitrates control room. As at 12 July 2002 the meter was set to trigger the alarms if the pH of the liquid in the tank was detected to be at a level of one or lower. 12 At all relevant times the process condensate tank has also been equipped with a meter which activates visible and audible alarms in the nitrates control room when the liquid in the tank has an elevated conductivity level. Conductivity is a measure of the electrical conductance of water. The conductivity of waters that have a low pH is elevated (relative to waters that have a neutral pH) due to the increased concentration of positive hydrogen ions in solution in low pH waters. 13 In relation to the pH and conductivity meters in the process condensate tank as at 12 July 2002, the nitrate plant pit, the river valve pit and the diffuser discharge to the north arm of the Hunter River were all equipped with pH monitoring instruments. The data generated by these instruments could be read on displays in the nitrates control room. These devices were also set up to trigger visible and audible alarms in the nitrates control room if they detected low pH levels in the facility's waste water. However, as will emerge, the procedures in place to monitor these alarms were not adequate at the relevant time. The data from the instrument that monitors the pH of the discharge from the diffuser could also be read from a panel in a second control room at the facility known as the ammonia plant control room. 14 On 12 July 2002, a pond known as the "ammonium nitrates pond" was in place at Incitec's facility. The pond had a capacity of five hundred cubic metres and was lined with rubber material. It was possible to divert waste water from the process condensate tank away from the river discharge point and to convey it into this pond. This diversion could be accomplished by closing a valve, allowing the condensate to overflow into a pit and then pumping the condensate from the pit into the pond. The pond had been used to hold waste water characterised by low pH prior to the events of 12 July 2002. 15 Three alarms relevant to the waste water system at Incitec's facility were activated in the nitrates control room on the morning of 12 July 2002 in the following order.