(a) the maximum penalty available for an offence reflects the "public expression" by Parliament of the seriousness of the offence. The task of the Court is to assess the relative seriousness of the offender's particular offence in relation to a worst case for which the maximum penalty is provided: at 698;
(b) a maximum penalty is to be imposed where the case falls within the worst category of cases for which the penalty is prescribed, but this does not mean that a lesser penalty must be imposed if it is possible to envisage a worse case: at 698;
(c) the court must keep in mind not only the facts which establish the seriousness of the offence, but also those which tend to mitigate that seriousness or exculpate the offender, and where a relevant fact is the subject of conflicting evidence of like probability, the court should resolve the conflict in favour of the offender: at 698;
(d) the offender can only be sentenced for the offence for which it has been convicted, although the Court must take into consideration the surrounding circumstances of the offence provided they are not inconsistent with the plea or verdict: at 699;
(e) when imposing a penalty, the Court should have regard to the principle of "even-handedness" so that the penalty is not outside the pattern of sentencing relevant to the particular type of offence: at 701-703;
(f) when sentencing for two or more offences the court should have regard to the principle of "totality" by which the judge should evaluate, in a broad sense, the overall criminality involved in all of the offences and, having done so, should determine what, if any, downward adjustment is necessary in the aggregate sentences in order to achieve an appropriate relativity between the totality of the criminality and the totality of the sentences: at 703-704.
156 The utilitarian value of a plea of guilty should generally be assessed in the range of 10-25 per cent on sentence. The primary consideration in determining where in the range a particular case falls is the timing of the plea: R v Thomson [2000] NSWCCA 309, 49 NSWLR 383 at [160].
OBJECTIVE SERIOUSNESS
Maximum Penalty
157 The maximum penalty for an offence reflects Parliament's expression of the seriousness of the offence. In Markarian v The Queen [2005] HCA 25, 228 CLR 357 at [31] the High Court held:
"It follows that careful attention to maximum penalties will almost always be required, first because the legislature has legislated for them; secondly, because they invite comparison between the worst possible case and the case before the court at the time; and thirdly, because in that regard they do provide, taken and balanced with all of the other relevant factors, a yardstick."
158 In the present case the offences are serious. The maximum penalty for each of the three offences, in the case of a corporation, is $1 million and a further penalty of $120,000 for each day that the offence continues: ss 123, 152(a). Each offence continued from Monday 8 October to Friday 12 October 2007. Accordingly, the maximum penalty for each offence is $1,480,000.
Extent of harm caused or likely to be caused to the environment
159 If the harm is substantial, this objective circumstance is an aggravating factor: s 21A(2)(g) Crimes (Sentencing Procedure) Act 1999. The more serious the lasting environmental harm, the more serious the offence and, ordinarily, the higher the penalty: Camilleri at 701, Environment Protection Authority v Waste Recycling and Processing Corporation [2006] NSWLEC 419, 148 LGERA 299 at [148].
160 The pre-existing degraded state of the waters is relevant to the extent of the environmental harm but is not a mitigating factor: Environment Protection Authority v Waste Recycling and Processing Corporation [2006] NSWLEC 419, 148 LGERA 299, at [149] - [150]. In that case Preston CJ, in assessing the extent of environmental harm as substantial, took into account that the pre-existing aquatic environment of a creek was moderately disturbed by reason of its location on an urban fringe: at [157]. In the present case, the pre-existing state of the creek and tributary was degraded. I have held that the degradation was what would be expected in agricultural areas such as this, and was roughly 3-4 on a scale of 0 to 10 where 0 is anoxic and 10 pristine.
161 The offences seriously harmed the environment in the short term: see [98] - [106] above. Other than the death of aquatic life in the days following the pollution incident, there was no long term environmental harm. There was potential for harm to the public human health but that risk was relatively low: see [117] - [122] and [127] above.
162 The results of water sampling by EPA officers in October 2007, combined with the evidence of the prosecutor's scientific experts, Mr Julli and Mr Haine, indicate the nature of the harm caused and likely to be caused. The results indicate that aquatic material present in the discharge caused depletion of dissolved oxygen, which led to the asphyxiation of fish, eels and minnows and the death of macrophytes (plants living in the water). The water became largely anaerobic with no capacity to support aquatic organisms for about a kilometre. At the date of the offence the creek comprised a series of interconnected pools, flowing slowly. The harm by the time the regulatory authority was advised of the spill on the Friday had extended to the Sciberras property downstream. The harm to the creek and tributary from the entry points to that point was such that all life therein was affected if not dead. Remedial measures by the defendant were instituted but only after official intervention and at the suggestion of EPA officers.