MOROBE MINER # 6 NOVEMBER.indd - Morobe Mining Joint Venture

HIDDEN VALLEY
No tailings discharged into Watut
Hidden Valley Joint Venture (HVJV) is
committed to operating the Hidden Valley
mine according to international best practice
and PNG environmental laws.
To achieve this HVJV is implementing a rigid
program to contain tailings (fine-ground rock
that is left after processing the ore) as this is
important in preventing adverse impacts
to water quality due to sedimentation and
process chemicals. These measures include
the construction of a Tailings Storage Facility
(TSF), Managing Waste Rock and Sediment
and Erosion control.
HVJV is the first mine in PNG to successfully
construct and operate a TSF to capture all
tailings on site for the life of the operation.
The TSF has been successfully commissioned
and the dam wall will be raised in stages
throughout the mine life to prevent release.
HVJV also ensures that any downstream
seepage is collected and pumped back to
the TSF.
Managing waste rock from mining
operations also remains a priority for HVJV in
minimizing impacts to water quality.
The joint venture is working towards the
construction of stable, permanent waste
rock dumps.
To assist with the appropriate design of these
dumps, waste rock has been geochemically
categorized. To construct the dumps, hard,
competent rock is needed for under-drains
Morobe Mining Joint Ventures (MMJV) has
developed management plan to address
issues of increased sedimentation in the
Watut River related to its mining activities.
Under the project, action plans have
been established to reduce mine related
sediment. Other causes of sediment include
non-MMJV mining activity and natural
events such as land slippages. The plans
include:
• Fast tracking work to establish
stable waste rock dumps
• Expert scientific studies
• Erosion and sedimentation
mitigation strategies
• Ongoing community consultation
and engagement meetings.
and dump toes as well as vehicle access
to toe locations.
In 2008 HVJV commenced development
of access roads to the chosen dump toe
locations and engaged engineers to
design stable waste dumps.
As no suitable rock for dump construction
has been exposed from either of the open
pits to date, alternative sources of rock are
being evaluated.
Interim sediment traps will be placed below
the existing dumps to reduce sedimentation
in the Watut River.
HVJV is also implementing a sediment and
WRIMP addressing sediment issue
Tailings Storage Facility (TSF) at Hidden Valley, the fi rst in the history of mining in Papua New Guinea.
to assist. Specialist consultants are being
used and Klohn Crippen Berger has been
appointed as independent technical
coordinators.
The MMJV has acted quickly to reduce mine
related sediment contributions:
• Side-casting of waste rock ceased
at the beginning of September.
Additional resources have been
assigned to the construction of
interim rock toes below sidecasting
dumps
• Site-wide water management has
been improved and
• Rehabilitation programs,
including revegetation, have been
accelerated
erosion control program.
Under this measure ten (10) storm water outfalls
have been constructed on the ridge line
and internal access roads to convey water
down the slope and reduce erosion.
These consist of a corrugated half-pipe
cemented in place, with an energy dissipation
structure at the toe.
Consultants have also been commissioned
to develop an Erosion and Sediment Control
Management Plan for Infrastructure and
Construction Areas.
Kwembu villagers
attended the awareness
on October 15.
Benefit Sharing Agreement
awareness in pictures
David Hume, GM Sustainability and
External Relations speaking to Nauti
villagers on October 16.
The WRIMP project is managed by David
Hume as GM Sustainability and External
Relations reporting to the Hidden Valley
joint venture committee. Technical and
community affairs specialists from within
the joint ventures have been appointed
PAGE 2
Communication to stakeholders has taken
place, including to all river communities,
to explain the actions being taken to
manage sediment and reduce river impacts
Assessment of impacts on downstream river
communities are being conducted.
Charles Mota, HVJV’s CA cordinator conducts
the awareness for Wau LLG on October 16.