Caves or Concrete?

Forest and Bird, Issue 282, 1 November 1996, Page 28

Caves or Concrete?

ANDY DENNIS

Eugenie Sage

the saga of Alpha Creek

The distinctive limestone landscapes of the western Paparoa Range were not fully protected when the Paparoa National Park was created in 1987. Lobbying by cement manufacturer Milburn New Zealand meant that key areas containing sculpted creekbeds, bold limestone bluffs and numerous caves were excluded from the park. The area’s future is again controversial as Milburn now seeks planning consent to bulldoze a road for a limestone

quarry in Alpha Creek.

revisits this

intriguing part of the Paparoa a special area that should finally be given proper protection.

MONG THE more exquisite features of the densely forested limestone region west of the Paparoa Range are the small creeks that weave their deeply-carved courses across the tilted plateau which dips inland from the high grey-white ramparts that loom above the Punakaiki coastline. Most

of these creeks once flowed underground and they provide, in both their present form and their habit of frequently disappearing and reappearing, constant reminders of their subterranean origins. As surface streams, their sculpted beds and banks are now softened by rich coverings of mosses, liverworts, ferns and overhanging forest. It is this combination of lush vegetation and the sculptural effects of patient etching by acidic water on limey rock that makes them the most enchanting of the western Paparoa region’s more intimate karst (or limestone) landscapes. One of the best places to get access to these smaller limestone streams is from the Tiropahi Track, an old bush tramway

that follows the Tiropahi River through the coastal limestone hills five kilometres south of Charleston. The track wends its easy mossy way through regenerating beech/rimu forest, with lovely interludes of dark river, colourful granite boulders and high limestone bluffs. Near the inland end of the track (about an hour from the Greymouth/ Westport highway) a number of limestone streams join the Tiropahi’s tannin-stained waters — Alpha Creek from the north, and Waggon and Doubtful Creeks from the south. All three contain a superb range of surface karst landforms and, in the case of Alpha and Waggon Creeks, probably more caves within a relatively confined area than anywhere else in the Paparoa limestone country.

N THE CAMPAIGN to create the Paparoa National Park in the 1980s, conservationists made a strong case for including all of the western limestone region as far north as Ananui Creek (the stream that flows through the Ananui or Nile River caves) inland from Charleston. However pressure from local industrial interests resulted in most of the limestone country between the Nile and Tiropahi rivers being excluded from the park. Despite its containing numerous caves, spectacular gorges and the huge "Hole-in-the-Wall" natural arch, and being generally unsuitable for production forestry, the area was allocated to the state-owned enterprise Timberlands West Coast. A sizeable enclave was also excluded south of the Tiropahi River in Waggon

The chemistry of lime-rich rocks

N THE ENDLESS cycles of sedimentation, uplift and erosion through which new rocks are created and then worn down as they are exposed to the elements, limestones have come up with a special twist of their own. Besides being subject to the normal destructive processes of weathering and mechanical erosion, limestones also slowly dissolve in contact with water. This means that the sculptural forces at work on lime-rich rocks have a greater range of tools at their disposal than is the case with other types of rock. Limestone landscapes, as a result, often feature eccentric and extravagant architectural forms both on the surface and beneath the ground.

Limestones are sedimentary rocks in which calcium carbonate (or lime) derived from shells and skeletons of marine organisms provides more than half of the sedimentary ingredients. In contact with rainwater made even slightly acidic by the atmosphere or, far more effectively, by leaf-litter and humus from the forest floor, this calcium carbonate slowly dissolves. Over aeons, water slowly etches its way into joints and other weaknesses in lime-rich rocks creating a range of highly distinctive landforms often reminiscent of the way meltwater carves its way through the heart of glacial ice. As the process advances, underground channels take over from surface streams;

sinkholes and slots become common landscape features; deep gorges and canyons develop with natural arches, overhangs and alcoves; and all manner of weird and wonderful runnels and flutings are etched into exposed surfaces. Much the same kind of thing occurs beneath the ground where shafts, passages and caverns evolve as a result of the combined efforts of dissolution and erosion. It is here that some of nature’s more delicate sculptural talents are manifested in stalactites, stalagmites, shawls, flowstones and other works of natural artistry. These are created as slowly dripping water patiently deposits minute quantities of calcium carbonate that it has picked up earlier in its subterranean journey. In the western Paparoa region the limestone nearer the coast usually averages less than 70 percent calcium carbonate. Inland, however, these beds dip downward and are overlain by younger strata in which the calcium carbonate component regularly exceeds 90 percent. Alpha and Waggon Creeks both drain through zones of this younger, purer limestone. Which is why they contain such a density of caves and surface karst features. And also why a cement manufacturer like Milburn happens to find them so attractive.

Creek where Milburn had identified enough high-quality limestone to keep its Cape Foulwind works supplied for over 100 years at current rates of production. Notwithstanding its exclusion from the park, the then Minister of Conservation, Helen Clark, indicated to Milburn that she was unlikely to grant mining access to mine Waggon Creek because of its outstanding natural values and status as part of a gazetted ecological area. As a result, Milburn turned its attention to the adjacent area managed by Timberlands and, in particular, to Alpha Creek which had been partially logged by the Forest Service. Its natural values were not generally thought to be as significant as those in Waggon Creek, although it was

known to contain an interesting range of karst landforms including a number of caves. Milburn’s subsequent prospecting of Alpha Creek revealed enough cementgrade limestone to supply the Cape Foulwind works for about 30 years. With ministerial opinion still favouring protection of Waggon Creek, the company applied for a mining licence over the Alpha Creek deposits in 1990. At the same time as Milburn was investigating the commercial potential of Alpha Creek, the Buller Caving Group was also devoting more attention to the area. Led by long-time Westport caving guru Phil Wood (see box page 33) a small but dedicated group of local cavers located

and explored over 30 separate caves within an area of little more than one square kilometre — many previously unknown. They included one two-kilometre cave system known as Golfcourse and two others, Bamboo and Name Later, that each exceeded 600 metres — the latter containing many passages decorated with stalactites, stalagmites, shawls, delicate straws and large areas of roof and walls coated with gleaming soft white "moon milk". While Bamboo is less lavishly decorated than Name Later, it contains two fossilised whale skeletons that are at least 30 million years old, the most complete of which includes 14 vertebrae forming a low bridge across a narrow passage. The skull of this skeleton has not yet been located (and is probably still embedded in the adjacent limestone) but even without a skull, the skeleton is one of New Zealand’s outstanding Oligocene fossil specimens. The presence of these whale remains makes Bamboo a cave of

national (if not international) significance and it has already featured in television films made by the Cousteau Society and TVNZ’s Wild South. Most of the other caves in Alpha Creek have also yielded bones of extinct creatures, including those of at least six species of moa and the flightless South Island goose. T-:: DIRECT IMPACT of a Milburn mine in Alpha Creek would be to destroy 35 hectares of generally pristine beech/broadleaf forest and obliterate numerous surface and subterranean karst features including Bamboo cave (which is in the heart of the proposed mine area). Golfcourse and Name Later caves are both outside the immediate mine zone, but their delicate formations are unlikely to escape damage from sustained blasting and their complex hydrological patterns would also be

affected by increased sedimentation. In addition to the destruction that 30 years of mining would cause to Alpha Creek, Milburn’s preferred option for an access road would also have major impacts on the natural character of the area. The road itself would run virtually on top of the Tiropahi Track for about 1.5 kilometres at its inland end, and carry an estimated 140 heavy vehicle movements a day. At present Milburn’s cement works at

Cape Foulwind are capable of manufacturing up to 450,000 tonnes a year — about half New Zealand’s annual cement production. The works were built in the early 1950s to take advantage of deposits of high-quality limestone in the Cape Poulwind area. Distance to the current mine is less than four kilometres and rock is transported by huge dump trucks along a private road. Transporting limestone from Alpha Creek, by contrast, would

involve a 40-kilometre journey on public roads, including about 20 kilometres of the main Greymouth-Westport highway. The company is a major employer in the Westport region with 140 of its own staff and at least as many again owing their jobs to the company’s presence in the district. Originally a New Zealand company, Milburn is now more than 70 percent owned by one of the world’s largest cement manufacturers, the Swiss-based multinational Holderbank. The Cape Foulwind works is the only cement plant Milburn still operates in New Zealand (having closed former works in both Otago and Southland) although the company has substantial offshore interests including a recent $50-million investment in a cement manufacturing company in China. Milburn’s 1990 application for a mining licence for Alpha Creek was lodged just in time to be considered under the old Mining Act rather than the much stricter requirements of the 1991 Resource Management Act. It attracted substantial objections from conservationists. The weight of these objections appeared to have stalled the application at the Planning Tribunal, but Milburn’s determination to proceed with the venture was confirmed last year when it applied for resource consents to construct 3.5 kilometres of new road to the proposed Alpha Creek mine site. Since such a road would cross conservation land, Milburn has also applied for an easement from the Minister of Conservation under the provisions of the Conservation Act (see box page 34). In addition to the significant damage a mine would cause to the scenic, scientific, recreational and historical features of Alpha Creek, there are also serious shortcomings in Milburn’s applications for a mining licence and access road consents. Prominent among these is the poor quality of the company’s required environmental impact reporting. No real attempt has been made to investigate the possible presence of rare plants in the area; bird surveys were conducted on only three days in the cold April of a cold wet year; and freshwater research was confined to sampling two sites in the main Tiropahi River on a single day in June, although these were enough to indicate very high freshwater values for a river system in this part of the West Coast. Bat and lizard surveys were also grossly inadequate — for example no bat detector was used despite the Tiropahi being almost a stronghold for threatened short-tailed bats. And reports on native

A passion for caves

HEN YOU GO into Phil Wood’s menswear shop in Westport and edge your way through the crowded racks of trousers and jackets to the cavern-like office at the back, you find yourself not in the room where the proprietor does his accounts, but in an archive of limestone and caving information perhaps without parallel in the country. Phil’s fascination with the karst landscapes of the Buller region began almost 50 years ago when, as a teenager, he visited caves in the Fenian area near Karamea and had some of his photographs published in the widelyread Auckland Weekly News. The interest evolved into a dominant passion during the 1970s when, with the Westport venturer scouts, he began systematically exploring the Charleston limestone district. Exciting new discoveries were always a possibility on these journeys and as local interest in caving grew, Phil helped to found the Buller Caving Group in 1979. Since the early 1970s, in between running his clothing shop and helping to bring up seven children, Phil has discovered, by himself or with others, about 150 new caves in the Buller region. Sixty of these are in the Oparara district near Karamea, with most of the rest at the Charleston end of the western Paparoa limestone belt. Many of these caves are small and are only of local interest. But others have proved of major importance. Foremost among the latter is the Honeycomb Hill network in the

Oparara which contains 14 kilometres of passages and 70 entrances and has yielded subfossil bones of 52 species of birds — 27 of them now extinct and three of them new to science. This collection of bones is the most significant ever recovered from a single New Zealand cave. In addition to discovering, describing and mapping numerous caves, Phil has tirelessly campaigned to protect what he sees as a highly vulnerable (and nonrenewable) part of our natural heritage. He fought for seven years to secure protection for the Ananui (Nile River) caves and catchment near Charleston, and also played a major part in protecting the Honeycomb Hill complex. His 12 years on the West Coast Conservation Board coincided with the long campaign to create the Paparoa National Park, and for the past decade or so he has been battling to protect the caves and karst features of Alpha and Waggon creeks. It is not easy standing up for conservation on the West Coast, but Phil Wood has been doing it for most of his adult life. As far as caves are concerned, his reasons are simple. "The area is too important as a caving and karst resource to be destroyed by mining," he wrote in one of several submissions on Milburn’s Alpha Creek proposals. "Such areas, important for future generations for tourism and enjoyment, and possibly for yet unforecast scientific value, are irreplaceable. These values need to be recognised when evaluating land for mining, against land which may require a little more effort to mine, but does not have the same long-term ecological value."

Alpha Creek the legal labyrinth

EVERAL MINISTERS, local be councils and the courts have a say in the future of Alpha Creek’s subterranean landscapes. The proposed mine is on land managed by Timberlands West Coast so any decision on access for mining lies with the Minister of State Owned Enterprises using the commercially focused provisions of the SOE Act, rather than conservation legislation. Publicly, Timberlands has not opposed the mine and has concerned itself only with the way in which forest cleared from the site would be disposed of. Milburn’s proposed road to the mine crosses conservation land. After considering public submissions (yet to be called for) the Minister of Conservation will have to decide whether to grant an easement for the new road. The department is seeking further information from Milburn on the road’s likely impacts on vegetation, wildlife and karst systems. DoC’s decision on the easement application is important because of the other

decisions which are stacked like dominoes behind it. These include Milburn’s 1995 applications under the Resource Management Act to the Buller District Council and the West Coast Regional Council for land-use and related resource consents for the access road. At the company’s request the councils have put these applications "on hold" until the easement issue is decided. The Environment Court (formerly Planning Tribunal) may be the final arbiter of the resource consent applications given the strong opposition they attracted from Forest and Bird, Buller cavers, the West Coast Conservation Board and others. The Environment Court also has to consider the objections to Milburn’s 1990 mining licence application under the supposedly defunct Mining Act 1971. The excessively liberal transitional provisions in the Crown Minerals Act mean that applications made under the 1971 Act will continue to be considered under that Act

well into the next century, as if the Resource Management Act did not exist. So Milburn escapes either having to apply for land-use and related resource consents for the mine itself, or having the mine’s effects on vegetation, wildlife habitat and karst systems considered in terms of sustainable management. Recommendations from the Court go to the Minister of Energy who makes the final decision. A DoC "no" to the access easement is far from guaranteed. Departmental reports indicate a schizophrenic attitude to the mine. Some suggest the department considers itself bound by the recommendations of former staff in the late 1980s that the company direct its attention to Alpha Creek rather than Waggon Creek. Other reports show that DoC is well aware of the area’s natural values and the irreparable damage that both the road and the mine would cause Alpha Creek’s caves, streams, fossils and forests.

land-snails and cave fauna were made without any field investigation despite the area providing a type and quality of habitat that is likely to contain significant representatives of these often-neglected groups of smaller animals. Consultation with appropriate iwi has also been poor. Despite a claim that the area had no history of Maori occupation or use, it is clear that it is of considerable cultural importance to Poutini Ngai Tahu as are many locations in the western Paparoa limestone region. Numerous waahi tapu, urupa and other sites of cultural significance are present in the area and indica-

tions are that tangata whenua are likely to be as strongly opposed as conservationists to the prospect of a mine and access road. Other sources of limestone exist that could meet the company’s long-term needs. There are extensive tracts of lowland limestone elsewhere in the Buller region some of which are in areas that

have been extensively logged or cleared for farmland — such as north of Charleston or near Inangahua. Milburn is adamant that none of these areas are suitable to meet its long-term needs (on account of the quality and extent of the deposits or problems with access and the costs of overburden

removal). . But $ prospecting s so = far has been carried out only by the company’s own agents and no independent assessment of these alternative areas has been made. Moreover, the company’s continuing doubts about the extent and quality of the limestone in the Cape Foulwind mine that it has worked on a daily basis for over 40 years must lead one to question its ability to be definitive about these other limestone areas, given both the intermittent nature of prospecting and the rugged country and dense vegetation involved. VEN IF MILBURN could provide a satisfactory response to all of the above objections, this is not the time to issue consents for a mine and access road that are unlikely to be needed for several decades at least. One of the pillars of the Resource Management Act is the onus on safeguarding options for future generations. It is difficult to think of an action that would be more at odds with this philosophy than handing over the fate of an important natural area presently owned by all New Zealanders to a foreign-owned company whose use of the resource would result in large-scale modification. Not only should any decision on the mine be left to those who are more likely to be affected by its consequences, a better base of information is needed before that decision can be made. At the very least, more work needs to be done on the biology and hydrology of this part of

the Paparoa limestone landscape, and an independent assessment made of alternative sources of limestone elsewhere in the Buller. And who really knows what is likely to happen over the next few decades to the New Zealand cement industry generally, the processes of cement manufacture, the state of the Buller bar and West Coast rail link, or the ownership of Milburn? More fundamentally, should 30 million years of natural evolution be sacrificed for 30 years of manufacture of a substance which, whatever its utilitarian qualities, so often seems out of harmony with the rhythms that nature imposes on landscape and environment? Or should a major industrial operation be allowed in an area of exquisite natural beauty and tranquillity; especially one whose intrinsic and cultural values are still only gradually being discovered, and whose opportunities for public escape, inspiration and quiet enjoyment can only increase in value in a world that continues to get faster, greedier, and more covered in concrete?

Anpby DENNIS is a freelance writer, editor and conservation consultant. He is a member of the Nelson Conservation Board.