Environmental improvement, snail documentary
27 March 2008
Solid Energy records further improvement in environmental performance and releases snail documentary
Solid Energy has today released published its 2007 Environmental Report reporting that for the second year in a row, the company has met its overall policy objective of having a net positive effect on the New Zealand environment. The overall improvement for the year to 30 June 2007 was 6.6% .
Solid Energy Chief Executive Officer, Dr Don Elder, says: “This result is very encouraging given that the area of land affected by our operations actually increased by 8%, mostly due to our acquisition of New Vale Mine in Southland and increased production and other activities at Stockton Mine in the Buller. We’ll be working hard to maintain that improvement in the current year.”
The report outlines the commitment Solid Energy has to managing the environmental impacts on its sites, spending about $20 million per annum on a range of on-site initiatives, including rehabilitation, improving water quality, the reuse of waste streams, the creation of public recreational resources from former mine sites and on environmental research and development.
“This figure also includes the investment we’ve made in protecting the native land snails relocated from the Mt Augustus ridgeline of Stockton Mine. We are now into year three of a 10-year programme to collect and relocate the 6,000 plus snails collected from the site. Two-thirds have now been released back into the wild and the remainder are being kept in captivity at the Department of Conservation’s facility in Hokitika.
Snail the Movie: “To mark the end of the first stage of the project we’ve released, with the Environmental Report, a 20-minute DVD documenting the programme to date, says Dr Elder. “The story of the snails is quite remarkable. It has received huge publicity, often generated by opponents of the initiative, which has at times overshadowed the good work by our staff and the Department to enhance the prospects of this snail population.”
It is still too early to draw any conclusions about the long-term outcome of the programme. “Since the first group of snails was released in December 2006, we have tracked a selection of these which were fitted with small transponders,” Dr Elder says. “The snails in the wild are typically thought to live around 10 years, meaning an average survival rate in any year of around 90%. Overall survival rates of the groups of snails we are monitoring range from 97% (in captivity) to 90% for one group in the wild and 75% for one other site.
“Along with the 6,115 snails, we recovered 1,283 clusters of eggs. Of these, 168 individual eggs have hatched in captivity with a better-than-90% survival rate. Some 484 eggs have been laid in captivity, and are expected to take up to a year to hatch. More than 1,000 eggs have been returned to the wild.
“In addition, it is estimated there are another 600 snails remaining in the source location, outside the mine site,” he says. “The captive population is growing, which is a very positive reinforcement for the programme carried out over the past three years and gives us a high degree of confidence in our ability to establish a viable wild population.
“There is still a lot of work to be done to understand the causes of the snail mortality and to confirm that these initial monitoring results are representative of all the snails released back into the wild. For example, we believe the weather has had an impact; a very frosty spell in the winter, and just recently the hot and dry summer.
“Solid Energy is working with the Dpartment to better understand how significant this unusual weather has been for survival rates and to assess what other factors may have come into play. We are also undertaking further population modelling to get better estimates of natural survival and reproductive rates,” Dr Elder says.
Solid Energy and the Department, advised by expert scientists, are working together to develop a management plan for the snails in captivity, strategies around further snail releases, ongoing monitoring and predator control on release sites.
 The Solid Energy e-measure system is now in its fifth year, scoring the company’s cumulative negative and positive effects on the environment, based on a wide range of factors. It identifies the company’s “worst” effect (if it did no environmental work at all), the actual effect from all site activities and the positive benefits from off-site mitigation work. 34 sites were assessed for 2007, including 14 active mine sites, coal handling, processing or loading sites, 12 inactive mine sites and 8 offset mitigation areas.