Daily Archives: October 14, 2011

Dispersants used in New Zealand spill “more harmful than the oil itself”


OIL SLICK: There is concern about the effects on the environment of using dispersant to break up oil from the stranded ship Rena.

Dispersants ‘worse than oil’

Stuff | Oct 11, 2011

by MICHELLE COOKE

The dispersants being used to break up the hundreds of tonnes of oil leaking from the grounded Rena could be “more harmful than the oil itself”.

Maritime New Zealand (MNZ) has used Corexit 9500 to help break up the oil, but University of Southampton oceanography lecturer Dr Simon Boxall said using dispersants could cause unnecessary harm.

The UK banned the use of Corexit dispersants in 1998 and Sweden has a blanket ban on all dispersants in the marine environment, Boxall said.

“In their raw form some dispersants can be very toxic and I believe will do more harm than good,” he said.

“They are more harmful than the oil itself and they are not less toxic than dishwashing liquid.

“Dishwashing liquid doesn’t carry hazchem advice and you don’t wear protective clothing and masks to do the washing up. In this case – with limited knowledge of the region – I’d advise caution on use of dispersants.”

But Environment Minister Nick Smith said Corexit was no more toxic than dishwashing liquid and had been approved by the Environmental Protection Agency.

He said at least 1800 litres of the chemical dispersant had been used with variable results.

In New Zealand, Corexit can be used in sea water but not fresh water.

Boxall has studied the Erika oil spill on France’s Brittany coast in 1999 and the MV Braer oil spill in the Shetland Islands in 1993.

He said oil broke up naturally after the Erika oil spill and “little human intervention took place”.

He estimated last night that it should take between four and six weeks for the oil to be naturally dispersed.

But another 300 tonnes have since leaked into the ocean, which means the natural process could take longer.

He said the stormy weather was “both a pro and con”. While it hindered the salvage operation, it would also help disperse the oil.

MNZ started using Corexit last week to disperse the oil from the Rena, but was also looking at using alternative dispersants.

National on scene commander Rob Service said last week that despite initial indications that dispersant testing had proved effective, further analysis had confirmed Corexit was not dispersing the oil.

MNZ said on its website chemical dispersants were an “important option” and should always be considered in the most effective “first stage” of the response strategy.

A spokesperson for MNZ said results from a trial of Corexit on Thursday and Friday proved inconclusive and while it planned to use it this morning, the weather hindered that operation.

Corexit is dispersed from the air, but it was too cloudy to fly today.

Helicopters have been on standby all day, waiting for a break in the weather so spraying could continue.

The chemical only worked on fresh oil and would not work on oil that had been in the ocean for more than three or four hours.

“If it’s still coming out tomorrow then we’ll continue to use it,” the spokesperson said.

Commonwealth Scientific and Industrial Research Organisation (CSIRO) research scientist Professor Nic Bax, who leads the Biodiversity Hub at the University of Tasmania, said nature would play its part but dispersants could also be helpful in breaking up the oil.

“Dispersants used to be quite toxic but now are considered to be much less toxic than the oil itself, so the main environmental decision regarding their use is determining where the oil will have least harm.”

“Spilt oil that remains at the surface will gradually be dispersed by natural physical processes at least in high energy environments. Oil that reaches low energy environments or gets buried in sediments may persist for several years.”

The University of Houston in Texas is currently researching new types of dispersants which are more environmentally friendly.

Cold La Nina winter forecast for B.C. and Alberta

CBC News | Oct 11, 2011

A U.S. weather forecasting company is predicting a very cold winter for B.C. and Alberta this winter, but it is far from clear if that means more or less snow for West Coast ski resorts.

“This winter could be one of the top three coldest winters in the past 20 years for Vancouver and Victoria, British Columbia,” according to the long term forecast issued by Pennsylvania-based Accuweather.

The company’s senior meteorologist Brett Anderson is forecasting the region will see temperatures as much as five degrees lower than normal as several arctic air masses slide down through British Columbia and Alberta this coming winter.

“Edmonton, Alberta, will likely be in the deep freeze for the fifth consecutive winter,” said the forecast.
More snow not forecast

Officials at the Whistler Blackcomb ski resort say they are hoping the La Nina weather pattern brings lots of snow on the slopes this winter. The resort is scheduled to open on Nov. 24 and already snow is piling up in the upper slopes.

Last year a La Nina pattern brought the second snowiest year on record for the ski resort, with more than 15 metres of snow. The record snowfall for the resort is nearly 17 metres, set in the La Nina winter of 1998/99.

But Anderson says the La Nina forecast does not mean B.C. or Alberta will necessarily get more snow.

“It’s either one or the other,” said Anderson.

Cold air doesn’t hold moisture very well, he points out, and if it’s going to be snowy, especially in western parts of British Columbia, “it’s usually not going to be terribly cold, especially in the mountains.”

“Strong La Ninas can lead to wet winters along the West coast, but I am predicting a moderate La Nina this winter,” Anderson said.

Environment Canada Senior Climatologist David Phillips is unwilling to match any of the predictions.

“Oh, I think it’s pretty brave of somebody to go out on a limb and suggest this will be the winter from hell or however they are describing it,” said Phillips.

Phillips says it’s true this is a La Nina year and in general, that means conditions are likely to be cooler, with more snow.

But he notes last year was a La Nina winter, and that did not mean any extra snow for lower elevations like Vancouver and Victoria.

“Yes there was certainly a lot more snow than the previous one, the Olympic Winter, but it was still on average a bit below normal, and temperatures were fairly close to normal,” he notes.