177 Snowy Hydro submits that in the following circumstances its control over the causes of the offence should be assessed at the lowest end of the scale:
(a) FRH had control of the construction site, it had prepared the environmental management plan (which Snowy Hydro understands contained a risk assessment), and it was responsible for supplying and maintaining environmental controls, including the silt curtain or curtains, as an effective environmental control;
(b) FRH was contractually responsible for ensuring compliance with regulatory requirements and for performing the works in an environmentally responsible manner;
(c) it follows that Snowy Hydro, as a matter of contractual obligation and fact, had no control over the procurement, deployment and maintenance of the silt curtain;
(d) the coffer dams being temporary work, FRH was responsible for their design, construction and removal;
(e) on the other hand, Snowy Hydro acknowledges that it had relatively unfettered access to the site, it approved the environmental management plan, it had the contractual power to approve proposals for temporary works and the contractor was obliged to prepare method statements;
(f) in practice, however (i) Belmadar/FRH was retained because of its experience and skills in performing construction works; (ii) the incident occurred at the very end of a productive and successful principal - contractor relationship such that by the time of the incident Snowy Hydro was directive only to the extent that it was necessary to achieve the required dimensions of the outlet channel; (iii) the temporary work likely to be considered in detail by Snowy Hydro were those with a potential to impact on the quality of the permanent works; (iv) Snowy Hydro never received proposals for the construction of the coffer dams; (v) Snowy Hydro never requested nor received a written proposal for the removal of the coffer dams, nor a work method statement or risk assessment; (vi) Snowy Hydro was not informed that FRH would remove the rock coffer dam before the clay coffer dam;
(g) Snowy Hydro should have obtained a contractor's risk assessment which addressed the risk of sediment going downstream from the excavation works and the plunge pool, as well as the controls needed to prevent pollution from either source;
(h) there is a distinction between control which in hindsight it could have exercised over FRH under the contract, and control which as a matter of practical reality it was able to exercise having regard to the scale of the project and the relationship with the contractor which had evolved over the life of the project. The quality of the relationship was informed by a previous, successful experience in which FRH deconstructed a temporary clay coffer dam in Lake Jindabyne. Snowy Hydro's failure to request FRH to provide a detailed methodology for the removal of the subject coffer dams was a measure of its confidence in FRH;
(i) in light of the relationship between Snowy Hydro and FRH, Snowy Hydro had little, if any, practical control over the removal of the coffer dam;
(j) Snowy Hydro accepts that it became aware on Monday 31 July 2006 of discoloured water downstream of the silt curtain and that it was a failing in its system for that knowledge not to have been transmitted to its construction manager, Mr Mayhew. However, inspections and sampling showed no real cause for concern. It was not until 3pm on Tuesday 1 August that increasing discolouration downstream became apparent to senior Snowy Hydro personnel. From this time Snowy Hydro increased its supervision. That evening Mr Jones directed that works were to continue in a way that did not send turbidity down the Snowy River and that the scope of the work could be modified if it became apparent that there was a risk that that would occur. That was reasonable;
(k) when, on the morning of 2 August 2006 it because apparent that the additional controls implemented by FRH were ineffective, Snowy Hydro acted properly to stop all work below water.
178 In my opinion, Snowy Hydro had adequate control, both as a contractual right and as a practical reality, to prevent works from being carried out that caused pollution to the Snowy River. Its contractual powers are summarised at [19] - [21] above. Its Superintendent had power to require a method statement and risk assessment, to suspend works and to give directions. Its contract with FRH noted that pollution was of "major concern" to it and that the Superintendent would enforce the requirements for soil conservation and erosion controls "rigidly". The plunge pool commissioning works posed an obvious pollution risk which required close attention by Snowy Hydro.
179 Having regard to (a) Snowy Hydro's obligations under its environmental protection licence not to pollute the Snowy River; (b) its express contractual declaration that pollution was of major concern to it; (c) the degree of contractual control which Snowy Hydro was able to exercise; (d) its degree of involvement in relation to the works; and (e) the critical importance of the plunge pool commissioning works in terms of the pollution risk that it posed, I consider that Snowy Hydro should have exercised close supervisory control over the design, methodology, risk assessment and implementation of the works. At discussed earlier, that includes obtaining and approving a method statement and risk assessment before the work was carried out. It is not a sufficient answer to say that Snowy Hydro's prior experiences with FRH, including the earlier removal of another coffer dam to the intake channel in Lake Jindabyne, had engendered confidence. That earlier removal was different because on that occasion there was nothing equivalent to the riparian flow, the turbid waters of the plunge pool and the connection to the Snowy River. Moreover, the removal of the clay coffer dam in Lake Jindabyne was not as uneventful as Snowy Hydro has suggested in that the turbidity of the plunge pool was, or was likely to have been, due to that removal (see [53] above).
Reasons for commission of offence
180 The objective seriousness of an offence may also be measured by reference to the reasons for its occurrence: Axer Pty Ltd v Environment Protection Authority (1993) 113 LGERA 357 at 366 per Badgery-Parker J. There were no deliberate, commercial reasons for the commission of the offence. The systems which Snowy Hydro had in place at the time in relation to its supervision of FRH were deficient.
Conclusion
181 Overall, I conclude that Snowy Hydro's offence is of moderate objective seriousness.
SUBJECTIVE FACTORS
State of mind of offender
182 A relevant subjective factor in a strict liability offence such as this is the state of mind of the offender: Bentley v BGP Properties Pty Ltd (2006) 145 LGERA 234 at [201] - [208]; Hardt v Environment Protection Authority (2007) 156 LGERA 337 at [53]. Snowy Hydro did not intend to pollute the Snowy River. Ironically, it was engaged in the tasks of rejuvenating the degraded Snowy River, in respect of which it was otherwise successful. It thought that there were adequate environmental controls in place and the polluting event took it by surprise.