ALOA made a submission to the EPA VIC, providing comment on the current Landfill Licensing Guidelines draft, particularly in relation to Appendix 11: Preparation of construction quality assurance plan for a new landfill cell.
ALOA contests that within Appendix 11 that the CQA plan must also include Level 1 supervision requirements and hold points for sub-grade. This testing regime calls for bearing capacity of the sub-grade including lack of soft ground, groundwater relief trenches and extraction system, groundwater relief grid alignment, grades and levels and survey of installed groundwater relief system.
Whilst improved environmental standards are applauded, we note that some (if not many) engineered landfill developments in Victoria are constructed within disused quarry sites. Because the quarry sites have generally been developed to optimise the extraction of stone, they are unsuitable for landfill operations until significant filling works have been undertaken.
The filling works in disused quarries are undertaken to ensure a solid foundation for a future landfill liner, but in some cases are many metres thick, often 10-20 metres thick. To apply the requirements of Level 1 supervision requirements would be a significant expense without a proportional return. That is, if a 20-metre fill was required to allow the construction of an engineered landfill, testing the bottom level of fill would be of no value.
It is suggested that rather than applying Level 1 supervision requirements on the entire fill, that a more relevant depth of, say, 1m be subject to such scrutiny.