A 'dam' tricky situation

THE Papua New Guinean government is reviewing mine tailings management legislation which may result in a ruling that all tailings be stored on land – possibly affecting six of the eight operating mines in the country that practice river or ocean tailings disposal. By Cindy Brown
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Published in the April 2013 PNG Report magazine

The review aims to ensure protection of the country's environ­ment and its people and to modernise tailings management practices.

The Constitutional and Law Reform Commission released an issues paper in February to kick-start the process. It has been a long time coming. The issue was originally raised in 2007 but faded into the background until now.

CLRC secretary and environmental law professor Dr Eric Kwa stresses the paper is the tool to get the ball rolling.

"Government has no current position on the subject. Stakeholder feedback is critical to crystalise issues and determine mutually acceptable solutions as far as possible. I have already received many comments from miners and the private sector saying they are happy we have taken the bull by the horns and revived this issue in an inclusive way," he said.

The CLRC has established a working group with representation from the Chamber of Mines and Petroleum, the Center for Environmental Law and Community Rights, the Centre for Environmental Research and Development, the University of Papua New Guinea, the Mineral Resources Authority, the Department of Environment and Conservation and the Department of Geohazards Management.

The group will drive consultation, including public forums and minesite visits in various provinces. It will also confidentially review submissions in response to the issues paper. Responses are due in September.

Kwa said the CLRC wanted to have a draft report to present to the public for comment in October, with a report for government in December.

"We hope any new legislation or amendments would be enacted around mid-2014," Kwa said.

Government mining departments have been working on policies around waste management and Kwa said all parties would work together to ensure alignment.

Crucially, an outcome for tailings management legislation that makes the majority happy will require a fine balancing act. The overarching conundrum is achieving legislation that helps attract foreign investment - greatly needed to advance the country - and which also supports publicly and scientifically acceptable environmental and social impacts.

To date, Papua New Guinea has had no specific legislation for the management of mine tailings.

Miners manage waste in accordance with relevant legislation provided mainly within the Environment Act and the Mining Act (the exception is the state-owned Ok Tedi mine, which operates within its own act).

As mentioned in the issues paper, improvements specific legislation may bring include a standard process for risk assessments; more transparent environmental impact assessments with a shift of responsibility from miners to government; increased fines for environmental damage; and a sustainable mining plan which aligns project development with government capacity.

Introduction of specific or tighter legislation may also reduce public concern about environmental and social damage.

For example, the Ramu NiCo court case, which was instigated by local community concern over damage to the environment from the mine's deep-sea tailings placement plans, was settled in late 2011 in favour of the company. Ramu said its DSTP plans should proceed given its compliance to relevant legislation. Had there been more specific tailings management legislation, would Ramu have been able to proceed with its DSTP plans in the current form?

Aside from legislation, a globally groundbreaking report was published in 2010 about the general use of DSTP in PNG. It was commissioned by the government and prepared by the Scottish Association for Marine Science. The report aimed to improve understanding of DSTP's environmental impacts and included a baseline survey of Ramu's DSTP site. The report has resulted in best practice environmental guidelines for DSTP in PNG, which Ramu is adhering to.

The SAMS report concluded that DSTP in PNG could cause environmental damage - the extent of which could not be confirmed as there was very little historical scientific data.

SAMS surmised the government must decide whether DSTP could be used within a project, based on analysis of specific environmental and social impacts.

So it sounds like the Ramu mine will need close monitoring as it ventures into relatively unknown territory.

Alongside DSTP, three PNG mines employ the highly environmentally criticised riverine tailings disposal method - Ok Tedi, Porgera and Tolukuma. PNG is one of two countries in the world where mines continue to deposit tailings into the river (Indonesia is the other). So if RTD is believed to be too environmentally unfriendly, why is it still being practiced in PNG?

There is a gamut of possible answers. A major one is the challenging environment. Steep terrain, heavy rainfall and earthquake activity have historically posed too great a threat to large on-land facilities. Another reason is location - mines may be too far inland to use DSTP. RTD also holds a legacy advantage, in that once a mine employing RTD closes there is no on-land facility left behind for anyone to maintain.

If, as the issues paper questions, RTD and DSTP were banned in PNG, would it be a retrospective ban? For mines with ocean access, will DSTP be considered an option when on-land storage is not feasible and stringent social and environmental requirements could be met?

These are questions that need to be explored as part of the review.

The latest crop of big mining projects are at different stages of potentially planning on-land facilities. Marengo's Yandera, Newcrest and Harmony's Wafi-Golpu, Indochine's Mount Kare and Xstrata's Frieda River have all signalled intentions to take the higher ground, so to speak.

So why the shift towards this method? Aside from technical and economical viability, maybe the trailblazing Hidden Valley mine has provided inspiration, coupled with the pressure to follow international standards.

Newcrest and Harmony's Hidden Valley is the first PNG mine to incorporate a major on-land tailings storage facility. The dam is designed to be around 160m high, which will make it one of the highest dams in the world.

It has been a pioneering project and a tangible example that the country can incorporate world's best-practice tailings management.

Klohn Crippen Berger mining environmental group vice president Len Murray said tailings management had come a long way during his time in the industry.

Murray is very supportive of PNG's move to review its tailings management approach.

Originally a geotechnical engineer, Murray has worked extensively on tailings dam construction around the globe since the early 1980s, including in an ongoing relationship with PNG, in particular the Ok Tedi mine.

"These days, project site selection involves much more scientific, environmental and community aspects - it is no longer based only on physical engineering considerations," he said.

"Essentially, projects now have to take a sustainable, triple bottom-line approach."

Murray said tailings management in PNG (as with the rest of the world) could not be underpinned by a one-size-fits-all approach and there were pros and cons to each method.

"Most countries now do not practice RTD, as the community and environmental downsides overwhelm the engineering upsides," Murray said.

"Physically, the big advantage of RTD is once the mine closes, the community is not stuck with a tailings dam forever."

He said tailings dam legacy issues would still be a major impediment to employing terrestrial facilities in PNG.

"This is because most sites are in fairly remote locations and once the mine shuts its infrastructure is usually removed - including any township - and the access road disappears, which makes it hard to maintain the dam left behind," Murray said.

"However, responsible companies usually provide a sum of money for the dam to be maintained on a long-term basis, which can be an incentive for the local community as it could become a small industry for them."

Murray said most mine permits would include a requirement to describe the end use of the dam.

"In a positive outcome, dam sites can be turned into agricultural or residential areas as they are usually very flat and, in this modern day, dams are typically abandoned as ‘dry' so there is no pond. This is much safer and they can be grassed or treed over," he added.

A negative scenario for the community would be the instance of a miner going bankrupt and it being stuck with an orphan site and no funds.

When asked why Hidden Valley had been able to implement an on-land storage facility when its nearby neighbor Porgera had not, Murray advised that Hidden Valley was much smaller, with advantageous environmental conditions. He also highlighted kudos should go to Hidden Valley's owners for being the first to implement this method in the country.

"The Hidden Valley dam sits on a stable landform with a small catchment," he said.

"From my experience, on-land tailings facilities work well for sites in PNG with little or no catchment outside the tailings area. Hidden Valley's catchment area is less than 10 square kilometres, if not five.

"There is a lot more risk involved if a dam is built on a big stream, with potential for constant terrain erosion where normal flows could be four or five cubic metres per second but could jump to several thousand cubic metres per second during a big flood. The failed Ok Tedi Ok Ma dam site was located on such a very large catchment."

Given its myriad of challenges, Murray notes that PNG is a place where tailings disposal facilities must be rigorously designed since they will get regularly tested against floods, earthquakes and other geohazards. It will lead to globally important advances in tailings management techniques and the country is now following others in refining its legislation.

"The United States used to employ RTD, for example, in its Idaho Basin during the gold rush era in the late 1800s and this continued in the country until the 1960s when it decided RTD was no longer acceptable. Chile is another more recent example of the banning of riverine disposal.

"However, it would be very hard to develop detailed worldwide guidelines for tailings management as each site is so different. Most countries follow a set of high-level standards with their own twists."

Indochine Mining Mt Kare project director George Niumataiwalu has extensive exposure to tailings management in PNG and Fiji, including playing an instrumental role in Hidden Valley's storage facility.

Niumataiwalu said the Mt Kare gold mining project, currently in its feasibility stage, would not have proceeded if a tailings storage facility had not been viable.

"Mount Kare is being planned in accordance with the International Finance Corporation and World Bank guidelines, which include rigorous requirements for triple bottom-line planning," he said.

"This process ensures potential long-term negative impacts of the project are mitigated against from the outset. We are aiming to be a preferred and proactive responsible developer of the country's mineral wealth."

Niumataiwalu said sustainability costs were amortised from the outset, rather than choosing an option that might be economically justified in the short term but failed the triple bottom-line criteria over mine life.

"Mount Kare will benefit from Hidden Valley's lead. To its advantage, Mount Kare's tailings storage facility can be located on a more favourable topographic terrain, with less seismic activity," he said.

Niumataiwalu said the government review might determine those projects unable to include on-land tailings storage to then be assessed for viability under far stricter guidelines.

"The technology is there to design and construct tailing storage facilities under most conditions. In many cases in developing countries like PNG and Fiji, it is the regulatory components of approving and managing facilities that require more capacity to better represent state and community interests in ensuring responsible tailings management. More focused legislation will help the country maximise its massive mineral endowment benefit in a more sustainable way," Niumataiwalu said.

PNG Report will keep you updated as this hot topic unfolds.

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