A P lab discovered in Russell St is the latest of three Nelson properties tested for chemical contamination in the past two years.
New Zealand police are battling a dramatic increase in the manufacture, distribution and use of methamphetamine, with an average of 200 labs located each year.
That figure was heard by the Nelson District Court at the sentencing of 26-year-old Kimberly Anne Van Groenewoud, who admitted conspiracy to supply methamphetamine and possession of precursor drugs used in the manufacture of "P".
Her de facto partner Steven John Newsom, 27, has admitted the same charges, as well as one count of manufacturing methamphetamine after police found a clandestine laboratory at his and Van Groenewoud's Russell St home, in Stepneyville, Nelson.
Police began monitoring Newsom and Van Groenewoud's cellphone communications in 2011, the court heard.
The couple was arranging supply of methamphetamine from Auckland, with help of a co-offender, Shane David Ryder of Thames. They would typically source quarter or half ounces of P, each shipment yielding a potential street value between $140,000 and $280,000.
Police identified eight such deals between September 3 and December 19, 2011, though it was not possible to determine exactly how much of the class A drug was imported into Nelson during this period.
On December 19 police searched the couple's Russell St property where they located makeshift laboratory equipment and a half-cooked P extract.
Newsom admitted he tried to make methamphetamine by extracting pseudoephedrine from some pills he had. Police also found acetone, and other precursor items.
Text messages sent by Van Groenewoud to an associate revealed her frustration at living in a house "smelling like a lab", and were used in evidence by police.
Nelson City Council communications manager Angela Ricker said the council had assessed three P labs in the past two years, one in Stoke and two in Nelson.
The process for cleaning up previous P lab sites began when the council was notified of a location by police, Ms Ricker said.
A notice was added to the property file held by the council that it was a potentially contaminated site. That information would then come up when a potential buyer asked the council for a Land Information Memorandum.
She said testing, which was contracted to a specialist company, had revealed no contamination at the Russell St property.
The other two labs have been decontaminated and property notices were removed from their files, Ms Ricker said.
Tasman District Council's environmental health co-ordinator Graham Caradus said TDC had not been notified of any labs in the region since November 2010, when police identified a "shake and bake" operation at Greenacres Motel.
He said he did hear anecdotes about properties suspected of being labs, but said the council could only act after an official police notification.
In the summary of facts presented against Van Groenewoud, Newsom and Ryder, Detective Bruce McLachlan said police located an average of about 200 clandestine laboratories in New Zealand each year.
Such labs posed a real risk to the community as they involved several volatile chemicals, with complex reactions being conducted by people with little or no knowledge of chemistry, he said.
Mr McLachlan said the rise of methamphetamine had become a major criminal, social, law enforcement, and environmental problem, which, if unconstrained, "could impact significantly on the very heart of New Zealand society".
A police communications spokeswoman said the Nelson region did not have a big problem with methamphetamine.
Rather, cannabis growing operations were keeping police busy at this time of year, she said.
Newsom has pleaded guilty and will be sentenced upon completing a rehabilitation programme in Auckland. He faces a maximum sentence of life in prison. Ryder also admitted his involvement, and is yet to be sentenced.
Judge Tony Zohrab sentenced Van Groenewoud to 10 months' home detention. She and Ryder faced a maximum of 14 years in prison.
The judge took a starting point of four years, which he said was consistent with other sentences.
Van Groenewoud received a discount of 25 per cent for admitting her involvement, and a further discount for her personal circumstances.
Crown prosecutor Emma Riddell agreed a further four months discount was appropriate, to recognise Van Groenewoud's self-admitted rehab efforts, and her loss of liberty during the time she was awaiting trial.
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