Holcim recently applied to the New South Wales Department of Planning and Environment to reposition the extraction area for its Lynwood Quarry, which is currently under construction near Marulan, south of Sydney.
The company received approval to produce five million tonnes per annum from the site in December 2005 and construction of the quarry began in late 2010. However, in the process of preparing the operation for start-up later this year, Holcim discovered through drilling and material testing that its current approved resource presented “challenges and complexities”.
“[The] resource is more variable and characterised by more significant concentrations of either intense fracturing, alternation, clay or a combination of these characteristics, than was detected during the earlier resource assessment investigations,” Holcim’s preliminary environment assessment report explained.
It was said that the “variability and complexity” of the approved resource would make it difficult for Holcim to consistently supply the market with in-specification product from Lynwood Quarry.
A Holcim spokesperson told Quarry that the Lynwood Quarry site contained a “well understood” granite resource, and that a detailed technical rock quality assessment program had shown that its geology was “homogeneous, relatively unaltered and unfractured”.
“Source rock testing confirms it meets all relevant technical specifications for several of our key products,” the spokesperson stated.
Holcim’s development modification proposes to quarry the granite resource via a new, 76ha pit located west of the current approved resource. It was said that the new pit would produce approximately 120 million tonnes of quarry product, which would help meet the requirements of the local, regional and Sydney markets over the coming decades. The quarry’s current consent ends in January 2038.
Stephen Mossie, Holcim’s general manager of aggregates for NSW and the Australian Capital Territory, said the company planned to continue quarrying from the current extraction area while the second pit was established. Once the new pit was fully operational – which is expected in 2017 – Holcim would then gradually transition to using it as Lynwood’s primary extraction site, with the first pit to be backfilled.
In addition to the granite pit, the modification also includes a haul road to the existing plant, adjustments to the overburden emplacement areas and some associated infrastructure such as water management structures. Mossie confirmed that no modifications to existing plant would be required.
Mossie also noted that the project’s approved production volumes, hours of operation and methods of product transportation from the site would remain unchanged, and that the project was still on track to commence operations in August this year.
The approval process for the modification is expected to take approximately 12 months.