Inchbonnie Quarry

Management Plan

June 2015

CONTENTS

Summary

Section 1: Introduction

Section 2: Background

Section 3: Financial

Section 4: Performance Measures

Section 5: Council and Contractor Responsibilities

Section 6: Site Specific Methodology

Section 8: Quarry Restoration, Rehabilitation and Expenditure Plan

Section 9: Quarry Permits and Consents

Summary

This plan sets out the history and future plans of Incbonnie Quarry so there is a record of any major decisions, expenditure, permits and consents.

It identifies the objective of the quarry as well as the methods of monitoring the condition of the quarry and rock, and determines the annual funding and expenditure needed to retain the safest and most cost effective plan possible.

Section 1: Introduction

1.1 Purpose of a Quarry Management Plan

This Quarry Management Plan defines the objective and performance standards of IncbonnieQuarry for which the West Coast Regional Council has the ultimate responsibility.

This Quarry Management Plan:

-Identifies the service level for the quarry

-Describes the background of the quarry

-Describes the methods used to maintain the service level of the quarry

-Complies with the regulatory requirements of the current Health and Safety in Employment Act/s Regulations thereon and all relevant Permits/Consents.

Section 2: Background

Incbonnie Quarry is located in Incbonnie, 66.6km inland of Greymouth at the end of McArthur Road.

InchbonnieQuarry is a standalone Granite rock outcrop with typical heavy jointing with a subsequent tendency to produce large (10 tonne plus) individual rocks as part of the quarry cycle. Operated by WCRC for the exclusive production of Armour Grade Protection Rock (AGPR) with a range of .25 tonne through to rocks with an individual weight of 10 tonne plus.

InchbonnieQuarry Management Plan 20151

Section 3: Financial

3.1Direct and Overhead Costs

The below costs do not include the “stock adjustment” which is applied when product is sold or quarried.

That adjustment reflects the “cost of rock sold” and is not a cost of operating the quarries.

The below costs include direct costs and allocated overhead costs.

Part Year
Year To / 30/06/2006 / 30/06/2007 / 30/06/2008 / 30/06/2009 / 30/06/2010 / 30/06/2011 / 30/06/2012 / 30/06/2013 / 30/06/2014 / 31/03/2015
Incbonnie Quarry Specific Cost / $399.00 / $9,225 / $16,849 / $14,376 / $70,961 / $40,327 / $69,320 / $46,798 / $1,464 / $479.00

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Section 4: Performance Measures

The overall performance measure is to operate InchbonnieQuarry in the safest and most cost effective manner possible.

The following procedures will be adopted to ensure the adequacy of Safety and Efficiency.

Annually

Rock production meets specific target(s)

Procedures meet Health and Safety requirements

Performance Measure

Waste to rock ratio – 20% waste 80% rock

Lost time due to injuries/incidents

Random Health and Safety Audits

Section 5: Council and Contractor Responsibilities

To achieve the primary aim of the Regional Council InchbonnieQuarry it is essential that both the Contractor and Council ensure that all responsibilities under existing Health and Safety in Employment Law and relevant amended acts and regulations are recognized and acted upon.

5.1Contractor Responsibilities

It is expected that the goal of a ‘Zero Harm’ working quarry environment is achievable, operation expediency over safe work practices in WCRC quarries will not be tolerated under any circumstances.

It is expected that all contractors operating in WCRC quarries will follow industry accepted best quarry practices at all times.

Section 6: Site Specific Methodology

6.1Drill and Blast Methodology

Due to large size of rock produced from Inchbonnie Quarry, the quarry now has excavator and drill access to the top of the formation and it is possible to downhole drill as well as use horizontal holes to facilitate production of large dimension Armour Grade Protection Rock (AGPR).

A combination of downholes and toe holes have proved to be the most effective primary blasting technique to produce large dimension AGPR consistently.

The Contractors blaster in charge will get a feel for the minimum explosive qualities required to break the rock without excessive fragmentation.

The Inchbonnie formation does not lend itself to large production blasts and in the main is more suited to a “drill and pop” operation due to the very pronounced jointing present throughout the outcrop.

6.2Faces and Benches

WCRC has ensured that developed faces currently lie approximately north/south and are currently retreated toward the east.

Apart from the occasional removal of dangerous overhangs on either side of the outcrop as they occur during normal quarry operations the easterly retreat shall be maintained due to the limited width of the bench at the upper level.

As the face/s retreat the rock at the lower levels out to each side of the main outcrop can be extracted as a function of the quarry to ensure the maximum available resource is eventually extracted at Inchbonnie.

6.3Future Approximate Face Heights

Face heights in all WCRC quarries should be limited to 7-8m as a maximum but because of the particular geological considerations present at Inchbonnie i.e. very wide and distinct jointing separating extremely large individual blocks of rock these heights may vary widely.

In all cases where the recommended face heights are exceeded because of rock failure due to pre-existing geological factors and which lead to over height faces and face instability all due care and practicable steps must be taken to ensure that safety is not compromised in any way.

6.4Bunding

Recent changes to the Health and Safety in Employment Laws and all acts and regulations there on have made bunding in quarries mandatory. This bunding requirement includes all road edges, benches, faces, tip heads and associated terminal drop-offs where there is a risk of vehicle roll over or falls.

However, due to the nature of the outcrop at Inchbonnie Quarry it will be difficult but not impossible to construct continuous bunding at the upper levels and care will need to be taken while construction is underway.

Where bunding is not practical at the upper level due to limited room and work is not underway at the time, it will be necessary to place a full physical barrier at the top of the access road to close it off completely.

In all cases bunding must be the preferred methodology to deal with Terminal drop-offs with the final height of all bunds to be set out at least 2/3 the height of the largest wheel operating in the quarry.

6.5Waste Dump Management

Due to the very high quality of rock available at Inchbonnie and with its propensity to break with very little waste, the limited volumes of waste generated can be used to ensure level AGPR stockpile areas.

Wherever possible waste product will also be used for the construction of bench edge and access road bunding at the upper levels as it is required.

6.6Rock Stockpile Areas

At Inchbonnie Quarry AGPR will generally be stockpiled on the western end or in the area immediately adjacent to the cattle race on the northern aspect of the formation.

The WCRC Quarry Manager will ensure that these areas are marked out prior to commencement of quarry operations.

Although all quarry product ex the face shall be weighed as it is broken out prior to loadout to stockpile, the actual stockpiles shall be constructed in such a manner that facilitates physical measurement of rock volumes in the stockpile (regular shape, straight sides, consistent height etc.).

6.7Hazards and Issues specific to Incbonnie Quarry

  • Quarry adjacent to operational dairy farm
  • Herd/stock movement management issues
  • Steep terrain
  • Geological considerations
  • Fly rock potential
  • Very limited bench space at upper levels
  • Difficulties in constructing upper level bench edge bunding
  • Limited operational area
  • School bus route on main road
  • Potential dust hazard along access road
  • Dwellings in near vicinity

6.9Access Road Regrading and Future Haul Road Maintenance

It will be necessary to maintain the access road from the end of GDC gravel road along the farm raceway to the quarry and this may require a grading and spread of a GAP 40 gravel product from time to time.

Liaison between WCRC Quarry Manager, the land owner/sharemilker and the Contractor will be necessary during quarry cycles to ensure that adequate fit for all purpose access road conditions are maintained.

Section 8: Quarry Restoration, Rehabilitation and Expenditure Plan

The Restoration/Rehabilitation efforts of the last few years in the Council’s quarries mean that overall the future requirements have been somewhat reduced at all sites but in any case this Restore/Rehab expenditure must be viewed as a function of the ongoing quarries operation. It is therefore important to ensure that each quarry has a dedicated budget line to maintain a meaningful Restore/Rehab programme into the future.

The level of annual expenditure should remain reasonably constant being more or less in lock step with annual production volumes unless a large flood event or similar occurs.

In this situation Restoration/Rehabilitation costs will increase in line with any production surge but based on averages should equate to around $0.15 (15 cents) per tonne of armour grade rock produced to also provide an additional lump sum at closedown/decommissioning.

This lump sum will be required to deal with:

  • Roading issues
  • Public access
  • Long term safety issues
  • Pit slope and face stabilization
  • Drainage
  • Contouring
  • Landscaping
  • Land ownership/transfers etc.

8.1 Expenditure Requirements for InchbonnieQuarry

As at 1/09/2014 year one restore/rehab programme and expenditure requirements for Inchbonnie Quarry are as follows:

Landscaping/contouring to extent of main floor area / $1500
Planting using the “clump” methodology wherever possible / $1050
Weed control etc. / $750
Total first year expenditure / $3300

Thereafter: An annual expenditure of $1650 will be required to carry out the Restore/Rehab at Inchbonnie Quarry.

At the current rate of extraction the minimum life of Inchbonnie Quarry is expected to be 20 years.

Therefore assume 20 years at 7500t per annum will total = 150000t + 20% waste = 180000 all up.

Using an average of $0.15 per tonne the provisional sum for decommissioning at Inchbonnie Quarry totals: 180000t X $0.15 = $27000 LS at closedown.

Section 9:Quarry Permits and Consents

9.1 Crown Minerals PermitGAZETTED

Permit Number / GAZZETTED
Permit Term
Commencement Date
Expiry Date
Area

9.2West Coast Regional Council Consents Held

Resource consent Number / Date Granted / Term / Expiry
date / Purpose
99/245 / Sec 94 hold / Withdrawn / Withdrawn / Discharge to air

9.3Other Consents Held

Consent Number / Issuer / Date Granted / Term / Expiry
date / Purpose
RC08068 / WCRC / 19-06-2009 / 35 Years / 19-06-2044 / Land use

InchbonnieQuarry Management Plan 20151