A series of staged extraction and rehabilitation plans for the life of the quarry have been developed. The plan includes the development of the site from the current approved pit design to a proposed expanded pit footprint along with the associated progressive and final rehabilitation.

Staging plans take into consideration:

• Maximum resource extraction
• Internal storage of overburden and mine waste
• Site specific geotechnical assessment and allowable batter/slope profiles
• Access to expansion area internal overburden storage
• Staging progression plans on 5 yearly intervals
• Rehabilitation concept landform

Review of the November 2020 topography indicates that the current maximum depth of the quarry pit is in the order of 180 m below crest level, at approximately RL 21 m.

The design of an initial pit model was developed in consultation with Boral and technical experts. The initial pit model illustrates the final extraction of the resource within the current pit limits and proposed a realignment of the ramp to include a switchback on the eastern side to allow for the integration of internal dumping required as part of the expansion. The initial model then served as the basis for the development of the extension pit model and staging plans.

The proposed development of the pit extension is to be split into eight stages over a timeframe of approximately 32 years, subject to market forces. Over that period, Boral proposes an extraction rate of 800,000 tonnes per year (kt/year) consistent with current operations. The milestones and summary of extraction per stage are described in Table 1 below.

The key construction activities associated with the project include:

• Site establishment and clearing. As part of the extension, Boral will need to clear the future extraction extent of vegetation and debris to create a clear environment to begin quarrying.
• The visual and acoustic attenuation bund will be built using topsoil and overburden from the site.
• The proposed access tracks will be established level by level using heavy vehicles so that safe and efficient access to and from the active quarry face can be maintained.

Quarrying activity will then commence.