Sinking feeling shatters a dream home

By JO-MARIE BROWN

When Paul and Rhonda Wells went house-hunting in Taupo in 1997, the large sparkling pool in the backyard at 32 Invergarry Rd caught their attention.

With three grown children and seven grandchildren, the couple dreamed of weekend family barbecues and swimming in the summer heat.

But after buying their dream property, they are now caught up in a nightmare.

A slight bulge that appeared in the pool in 1999 was the first sign that something was amiss below ground.

That something was subsidence, a phenomenon that has now affected up to two dozen homes on Invergarry Rd and more than 100 industrial and commercial buildings in the surrounding area.

Residents and the Taupo District Council blame Contact Energy.

Since 1958, geothermal fluid has been extracted from beneath Taupo and the surrounding area to generate electricity at the Wairakei Geothermal Power Station.

But unlike many overseas operations, Contact does not pump the waste geothermal fluid back underground to the spot where it came from.

Instead, about 40 per cent is injected into the outskirts of the Wairakei-Tauhara geothermal field, and the rest is dumped into the Waikato River.

The pool at 32 Invergarry Rd is now empty. Its sides are so buckled that it won't hold water and its plastic blue lining will not stay in place.

Large cracks snake their way across the Wells' concrete driveway and up most interior walls. Cladding on the outside of their home has started to lift, and nails are popping out.

Mr Wells said that even if they spent tens of thousands of dollars repairing the damage done, engineers had told them they would be in the same position in two years.

The couple expect their home to be uninhabitable within five years.

"We now run a real risk of having our mortgage foreclosed because we've got no value left in our asset," Mr Wells said.

"Who in their right mind is going to buy this house?"

Next door, Brenda and Chris Penney have given up trying to fill the gaping holes that keep appearing between the walls and ceiling of their home.

"We don't think we'll be watertight by the end of the winter," Mrs Penney said.

"You can't imagine the amount of stress we're all under."

With their homes falling apart at the seams, Invergarry Rd residents were horrified to hear that not only was Contact refusing to accept responsibility for the problem, but was applying for resource consent to expand its operation and take 45 per cent more fluid.

"What they're doing is raping and plundering our environment," Mrs Wells said.

"We can't sit back and let that continue. Someone has to do something."

The Taupo District Council agreed and has spent $2.8 million of ratepayers' money over the past three years to oppose Contact's plans and convince the regional council to tighten its geothermal rules.

Mayor Clayton Stent said that the council wanted to protect the environment and ensure subsidence did not creep any further towards town.

And it knew residents could not afford a huge legal battle themselves.

"If the council didn't involve itself, then there are going to be individuals who are completely at sea - no insurance cover with their most valuable asset at risk.

"So it's a social responsibility that we have to our community."

The fight between the council and Contact played itself out during a four-month resource consent hearing in Taupo.

It ended a fortnight ago and three independent commissioners working on behalf of Environment Waikato are now sifting through a mountain of conflicting scientific and expert evidence.

Their job, in deciding whether to let Contact extract more fluid, involves assessing whether Contact is likely to be responsible for subsidence on the eastern outskirts of town, and therefore, whether the company should be forced to reinject fluid in the way its opponents want them to.

The council and Invergarry Rd residents insist that all of the fluid Contact takes should be returned to the middle of the Wairakei-Tauhara geothermal field to stop the ground from sinking.

Barrister Phillip Green, who presented the council's case at the resource consent hearing, described Contact as "a callous corporate citizen", unwilling to act with any degree of responsibility towards Taupo.

"Contact has set its face against this town," Mr Green told the commissioners.

"It has mistakenly assumed that putting power into the national grid somehow gives it a moral high ground. An assumed right to do damage to people, a community, a town."

But Contact's reply was just as scathing. Its lawyer, Trevor Robinson, raised questions as to the suitability of the town's location, saying there were inherent problems in expanding any town which lay over a geothermal field.

Mr Robinson also suggested the council had bombarded the commissioners with evidence to create the illusion that "where there's smoke, there's fire".

Contact believed that much of the material produced by the council was "irrelevant, misleading or wrong".

At the heart of the dispute is what will happen to the Wairakei-Tauhara field if all of the waste geothermal fluid is put back into the heart of the resource.

Professor Michael O'Sullivan, of Auckland University's Engineering Science Department, gave evidence on behalf of Contact and predicted the effect would be similar to pouring cold fluid into a jug of boiling water.

The boiling would stop.

Ultimately, he said, the geothermal reservoirs below ground would cool to the extent that the fluid extracted would no longer be hot enough to generate electricity.

Mr Robinson said Taupo residents would suffer because the geothermal bores on which many people relied for heating and hot water would drop in temperature, and the town's thermal features would dwindle as a result.

"Not to put too fine a point on it, there would be hell to pay," he explained.

"While at a human level, it might be tempting to await that point in time and then to say 'we told you so', that is not how Contact operates."

But a geothermal expert flown from the United States by the Taupo District Council disagreed with Professor O'Sullivan's assessment.

Dr Karsten Pruess said geothermal operators were reluctant to consider large-scale reinjection in the 1980s because of the concerns Contact had outlined.

But they had since tried it and found there were no ill-effects, and full infield reinjection was now standard practice at most geothermal power stations.

"In my view it is an anomaly that Wairakei is still disposing most of its waste fluids at the surface," Dr Pruess said.

"I believe this is simply a legacy from the 1950s and 60s when people had different views about balancing resource recovery with environmental protection and preservation.

"I have no doubt that if Wairakei had been developed for the first time in the 1990s, full reinjection would have been a fundamental and basic requirement."

Scientists on both sides also remain at odds over the cause of Invergarry Rd's subsidence.

Dr Pruess and other experts called by the council believed Contact's activities were definitely to blame.

But the company doubts the problem has anything to do with geothermal extraction.

Mr Robinson said the homes in Invergarry Rd were not tilting in the direction one would expect them to if they were suffering from deep-seated subsidence.

Rather, Contact believes the damage is being caused by ground movements on a small scale, close to the surface.

Now it is up to the commissioners to decide. But either way, time is fast running out for the Invergarry Rd residents and other landowners whose property values have plummeted.

Once again, scientists are divided over whether full reinjection will prevent their homes from sinking further or reverse some of the damage already done.

Brenda Penney just wants someone to buy her home so she can move elsewhere and get on with her life.

"Someone has to take responsibility and resolve this," she says.

"I don't care if it's Contact, the Taupo District Council or Environment Waikato. Someone's got to do it."

Mayor Stent said he understood the residents' frustration, but the council could not ultimately solve their problem.

"We've taken on the responsibility of fighting the fight for the community but we're not going to be able to deliver any solutions. That will fall very much between the regional council and Contact."