Image from the journal Environmental Science & Technology

• Radiation Still Leaking Into Ocean

• Concern About Marine Sediments

Last April, about a month after the Fukushima nuclear accident, concentrations of cesium-137 in the ocean near the plant peaked at 50 million times above normal levels, according to a study by the Woods Hole Oceanographic Society.

Last May, Woods Hole senior scientist Ken Buesseler told this page of his planned expedition to study the effects of radiation on the ocean.

Buesseler and two Japanese colleagues have just published a paper, Impacts of the Fukushima Nuclear Power Plants on Marine Radioactivity, in the journal Environmental Science & Technology.

“The release of radioactivity from Fukushima–both as atmospheric fallout and direct discharges to the ocean–represents the largest accidental release of radiation to the ocean in history,” according to a National Science Foundation synopsis of the study.

Concentrations of cesium-137, a radioactive isotope with a 30-year half-life, at the plants’ discharge points to the ocean peaked at more than 50 million times normal/previous levels. Concentrations 18 miles offshore were higher than those measured in the ocean after the Chernobyl accident 25 years ago.

Despite the alarming concentrations, the radiation rapidly diluted in the currents northwest of the plant, the scientists contend, and they should pose little or no threat to human and marine life. However, little is known about the effect of radiation on the lowest levels of the coastal ecosystem.

“We don’t know how this might affect benthic [bottom dwelling and subsurface] marine life, and with a half-life of 30 years, any cesium-137 accumulating in sediments or groundwater could be a concern for decades to come,” Buesseler said.

The radionuclides peaked in April when Toyko Electric Power was using water to cool exposed reactor cores and spent fuel and discharging the contaminated water into the ocean. The levels dropped dramatically in May when crews began capturing the contaminated water for treatment.

But even in July, radiation levels were still 10,000 times higher than levels measured in 2010 off the coast of Japan, the study found, and the plants “remain a significant source of contamination to the coastal waters off Japan.”

“There is currently no data that allow us to distinguish between several possible sources of continued releases,” says Buesseler.

“These most likely include some combination of direct releases from the reactors, or storage tanks or indirect releases from groundwater beneath the reactors or coastal sediments, both of which are likely contaminated from the period of maximum releases.”

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Scientists Will Track Fukushima Radiation to Study Ocean Currents

Hallandale Beach has abandoned six of its eight drinking water wells because saltwater has advanced underground across two-thirds of the city.

“The saltwater line is moving west and there’s very little that can be done about it,” said Keith London, a city commissioner for Hallandale Beach, who has worked on water conservation and reuse for the last decade.

A wall of saltwater is inching inland into the Biscayne Aquifer — the primary source of drinking water for 4.5 million people in South Florida.

A hundred years ago, saltwater intrusion was not a problem in the area. The Everglades seemed to hold more freshwater than residents could ever use.

But then swaths of the “River of Grass” were drained through canals to clear farmland and build single family homes. Utilities have been trying to keep saltwater at bay since the 1930′s. But saltwater has crept in to replace freshwater that drained out to sea.

Now, commissioner London and Hallandale Beach city staff need to secure a new source of . They are working on a deal to dig wells in West Park, another South Broward city about three miles inland. Hallandale would then pipe the fresh water back east.

The project will cost an estimated $10 million, says Earl King, Deputy Director of Hallandale Beach Utilities and Engineering. Residents will eventually pay those capital costs.

New drinking water wells are likely the cheapest alternative, London said. The city could build a reverse osmosis plant to filter out the salt, but the construction and maintenance costs would be astronomical.

“The energy needed to remove the salt would have made water cost 10 times, 100 times more than what we are paying now,” London said.

As the salt front crept inland, municipalities and agencies have restricted water use.

Gulfstream Park racetrack in Hallandale Beach, for example, was prohibited from pulling water from the Biscayne Aquifer in 2005. Gulfstream needs roughly 300,000 gallons every day for their 23-acres of pristine Celebration Bermuda turf.

Gulfstream managers opted to spend $1.5 million on a reverse osmosis filtration system. They pull water from 1,200 feet underground from the Floridan aquifer, a deep, highly-saline section of the aquifer.

The wall of seawater snakes up South Florida’s coast.

In one area in Broward County, the saltwater front is as far as five miles inland. In Miami-Dade, the saltwater reaches the eastern edge of the airport.

“The saltwater is slowly creeping west in cities like Dania Beach, Lake Worth and portions of Fort Lauderdale,” said Scott Prinos a hydrologist with the U.S. Geological Survey in Fort Lauderdale.

Prinos has tracked saltwater intrusion in South Florida for decades and he regularly tests the saltiness of a well dug in the heart of Hallandale Beach in 2005.

“This well, when it was first installed was fairly fresh and it’s become saltier as we’ve been monitoring it,” Prinos said.

He lowers a long hose into a narrow well, pumps water to the surface and sends it back to his lab.

The salt content of this well is thirty times saltier than normal.

The South Florida Water Management District and the U.S. Army Corps of Engineers monitor water control structures along drainage canals to prevent, and in some cases reverse, saltwater intrusion.

“In estuaries, you can see the salinity move inland,” said Susan Sylvester, Director of Operations Control for the SFWMD.

These control structures, like the one along the Miami River, act like a dam. They impound fresh water on one side, and that builds up pressure and pushes away the saltwater.

Commissioner London says saltwater intrusion will eventually touch everyone in South Florida.

It is likely saltwater will continue its westward creep. The USGS reports that sea level in southern Florida is currently rising by three quarters of a foot every century. As ocean levels splashes higher along beaches and canals, saltwater may keep inching inland.

London, 50, became a commissioner in 2006. On a recent Friday morning, he tended his lush garden and watched bees and butterflies suck nectar from white flowers. Despite thick greenery, there isn’t a single sprinkler.

“I have four, 55-gallon rain barrels that I capture rain coming off the roof,” London said.

London waters his garden with rain he has captured in his giant white plastic barrels. He curated his garden over the past 20 years so he does not need to use tap water.

“If everybody had one or two rain barrels, we could save millions, literally millions gallons of water a day,” London said.

Our water use in the past, said London — namely the drainage canals — led to the salty drinking water we have today.

“We’re all on this one little planet,” London said, “and what I do today is going to impact someone else down the road.”

With almost 100 million people in developing countries exposed to dangerously high levels of arsenic, and unable to afford complex purification technology, MU’s Professor Tsanangurayi Tongesayi has described arsenic removal by flaked PET bottles coated with cysteine, an amino acid found in dietary supplements and foods.

The work was reported at the 242nd National Meeting & Exposition of the American Chemical Society, a major scientific meeting with 7,500 technical papers, held on 1 September.

Tongesayi commented: “Dealing with arsenic contamination of drinking water in the developing world requires simple technology based on locally available materials. “Our process uses flakes from plastic beverage bottles. When the flakes are coated with cysteine and stirred into arsenic-contaminated water, they work like a magnet – the cysteine binds up the arsenic. Remove the plastic and you have drinkable water.”

He described laboratory tests of the purification method on water containing 20 parts per billion (ppb) of arsenic, twice the safe concentration set by the US Environmental Protection Agency for drinking water. The water was rendered drinkable, with 0.2 ppb or less arsenic – more than meeting the federal standard.

The method is straightforward enough for people without technical skills to use, said Tongesayi. It can use discarded plastic bottles available locally, and applying the cysteine is simple. Tongesayi is seeking funding or a commercial partner for development and commercialisation. He reported that the technology also has the potential for removing other potentially toxic heavy metals from drinking water.

Odourless, tasteless, and colorless, arsenic may enter drinking water supplies from natural deposits in soil and rock, or from agricultural and industrial sources. Symptoms of arsenic poisoning include thickening and discolouration of the skin; stomach pain, nausea, vomiting, and diarrhea; vision loss; and numbness in hands and feet. Arsenic has also been linked to cancers of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate.

CMN Correspondent
Tuesday, September 20, 2011

CHENNAI, INDIA: These entrepreneurs do not chase unrealistic dreams. Nor do they dream of leading a lavish lifestyle in mansions. Their motto: To provide clean drinking water to villagers and make them entrepreneurs.

A five-member team from IIT Madras – Vinay Sridhar Lohit Vankina, Vishruth Srinath, Arun Chandran and Ananth Jain – has developed a cost-efficient water purifier, Acquaregia, which not only provides purified water at as cheap as 25 paise per litre but also helps create entrepreneurship in every street. The team won the Genesis 2011 award which consists of a cash prize of Rs. 2,40,000. They are also eligible to get seed funding from angel investors, venture capitalists and entrepreneurs.

Inspiration

The team was inspired by a course on entrepreneurship in their institution. They turned that inspiration into reality by being entrepreneurs themselves. “We met a lot of entrepreneurs while doing the course. The kind of impact their ventures had on people and society made me realize that I also wanted to be an entrepreneur,” says Vinay.

According to him, entrepreneurship is about creating a change. “Whether it is in rural India or urban India, it doesn’t matter. I want India to be a better place. Aquaregia is one way by which a change can be made.”

Also read: Lack of enthusiasm bane of Indian SMEs

Aquaregia is a Latin word which means royal water and is used to describe a mixture of nitric and hydrochloric acids that can dissolve gold and platinum. “We feel water is as precious as gold and platinum. When we realized that 60 per cent of rural India does not have good drinking water, we thought we have to tackle the problem.”

They started their research on the project by speaking to scores of people. They found that the problem was not in the purification devices available in the market but with the cost. “We found that it is the cost that is a deterrent in rural areas. Even if you bring down the cost from Rs. 3,000 to Rs. 1,500, the rural India can not afford that,” said Vinay. They then decided that the device should not run on electricity, but should be durable and portable.

How this device works

Acquaregia has two tanks with four purification bulbs placed in between. The impure water is poured into the top tank and it passes through the bulb which is a combination of sand, saw dust, nano silver particles, etc, and what comes out is purified water. The device has the capacity to purify water of all the impurities found in the ground water.

The team now plans to use the customised bulb made by Tata to purify water. Their requirement in the first year of venture could be Rs. 10-20 lakh. They plan to use Rs. 10 lakh for prototyping and another Rs. 10 lakh for marketing. Once launched, the product will be available in three sizes of 50 litres, 100 litres and 150 litres capacity.

Instead of selling it to every villager, they plan to sell it to one person in a street. This person in turn can sell water to others and become a local entrepreneur.

“We plan to encourage micro enterprises in villages. So we plan to have an entrepreneur in every street. We want to make use of the networks of NGOs to reach out to people. At present, the other two founders are in a village in Vellore district to study the exact requirements of the villagers,” Vinay explained.

Acquaregia also has plans to collaborate with banks to help village entrepreneurs in taking a loan to buy the product. The three states they are looking at are Tamil Nadu, Andhra Pradesh and Karnataka.

“We want each street in every village in south India to have our product so that they can get clean drinking water. That way, we can get rid of all the diseases that come with contaminated water. We are not looking at the financial gains as none of us dream of lavish lifestyle in mansions. We want to be entrepreneurs who can make an impact in the society.”