The admission came when representatives from Coca-Cola Amatil, the Australian Food and Grocery Council and the Australian Beverages Council appeared at the final public hearing of the Senate inquiry into marine plastics.

"Ninety-six per cent of beverage containers are already collected through existing systems. As industry, we want to help the Government design a solution that focuses on capturing that last 4 per cent," said Coca-Cola Amatil in its written submission to the inquiry.

The public hearing in Canberra last week was the fourth held around the country, addressing the threat of marine plastic pollution in Australia and its waters.

"At a rate of four per cent, the amount of bottles and cans proliferating in the NSW environment is over 168 million per annum, [that's] 17,700 tonnes," said Dave West, national policy director of the Boomerang Alliance, which represents more than 30 environmental groups.

"Governments are moving towards banning plastic bags, which account for a quarter of this rate in litter. All takeaway food containers and cups represent just 53 per cent of the amount of litter the beverage industry is responsible for."

Mr West said, while "four per cent" is the figure used by the government, the number of beverage containers littered across the state could in fact be much higher.

The "four per cent" estimate is based on the assumption that about  70 per cent of all beverages are consumed at home, which equates to around 20.2 containers per household, per week, according to the NSW Environment Protection Authority.

That assumption also suggests those containers are disposed of or recycled at home, however this is not always the case.

A study commissioned by the EPA last year found only 12.6 containers a week end up in each household's bin.

"This means government and industry have lost some 1.1 billion (112,000 tonnes) beverage containers a year, in NSW.  It also means they have been consistently overestimating the recycling rate," Mr West said.

"The amount of beverage litter is appalling if you consider that that's what's left after government, industry, councils and NGOs in NSW spend over $162 million per annum to capture just 56,000 tonnes a year."

The NSW government has committed to implementing a container deposit scheme by July next year, with a decision on the model of such a scheme expected in coming months.

The final contenders in the government's decision-making process were a community-supported container deposit scheme and an alternative beverage industry-backed option known as Thirst for Good.

"Reducing the volume of litter by 40 per cent by 2020 is one of 12 Premier's Priorities for this term of government, and whatever CDS model is chosen by government will need to make a major contribution to achieving this target," said NSW Environment Minister Mark Speakman.

Domestic and international recycling companies have estimated there would be an investment of up to $160 million in a world's best practice container deposit scheme.

Companies such as Remondis, Envirobank Recycling, TOMRA and Revive Recycling have pitched their support for a scheme that includes 600-800 automated redemption points, automated and manual depots in lower population areas and hubs to service the commercial and industrial sector.

"A CDS in NSW using world's best practice will reclaim around 1 billion containers every year...and will upgrade the recycling of a further 2 billion or so. Together this is conservatively estimated to be worth around $35 million annually," said Markus Fraval, CEO of Revive Recycling.

smh.com.au