Rebalancing the nuclear debate through education

Better physics teaching with a particular emphasis on radioactivity and radiation science could improve public awareness through education of the environmental benefits and relative safety of nuclear power generation, according to leading Brazilian scientist Heldio Villar. He suggests that it might then be possible to have a less emotional debate about the future of the industry that will ultimately reduce our reliance on fossil fuels.

To environmental activists, nuclear power and environmental preservation are two antagonistic concepts. Nevertheless, nuclear power can generate huge amounts of electrical and heat energy with minimal impact on the planet, particularly in terms of much lower carbon emissions and pollution than is seen with power generation based on burning fossil fuels. Because of this cultural clash, activists have prognosticated doom for a world if we pursue the nuclear energy option, leading to public distrust of the nuclear industry and its relatives, nuclear research installations and particle accelerators.

“The introduction of the theoretical bases of radioactivity, radiation physics and nuclear power plants in the environmental education curricula will certainly result in a greater awareness of the public towards the reality surrounding radiation and radioactivity,” says Villar of the University of Pernambuco, who not surprising also works for Brazil’s Nuclear Energy Commission. “This initiative, coupled with a more realistic approach towards nuclear risks on the part of nuclear regulators and licensers, has the potential to make nuclear applications – not only in electric energy production but in other areas – more palatable to a public squeamish of another Three Mile Island or Chernobyl and the specter of nuclear weapons, rendering it more prepared to reap the benefits thereof.”

Ironically, in the 1950s and 1960s, nuclear power was once hailed as the best option for an energy-starved world. Nuclear reactors were seen as modern, reliable and, above all, capable of producing electricity ‘too cheap to meter’. Into the 1970s, the oil crisis sparked the first major interest in going nuclear on a much wider scale. However, even before Three Mile Island, activist groups such as Greenpeace were sounding unwarranted alarm bells and popular movies such as the China Syndrome, which does not have a disastrous ending, were fuelling the anti-nuclear movement.

Villar points out that it is widely accepted that Brazil and several other nations, are entirely capable of launching successful nuclear power programs, given their expertise, the availability of nuclear fuel and the pressures such as a lack of coal and the rising price of oil. “Electrical energy is scarce and obviously expensive,” says Villar, “a situation seen in several other countries.” Supposed “green” solutions, such as hydroelectric power, which has already been fully exploited in Brazil, as well as gas turbines, solar and wind power, tidal power and biomass, do not represent a cheaper alternative to nuclear he asserts.

Villar, H. (2011). The ‘threat’ of radioactivity: how environmental education can help overcome it International Journal of Nuclear Knowledge Management, 5 (3) DOI: 10.1504/IJNKM.2011.042006

Heavy metal – in and around the lake

Heavy metal pollution of lakes has a seriously detrimental impact on people and ecosystems that rely on such bodies of water. According to a study published in the current issue of Interdisciplinary Environmental Review, researchers have focused on the physicochemical properties and toxicology of water from and around Thane City of Maharashtra.

Environmental chemist Pravin Singare of Bhavan’s College, in Mumbai, and colleagues highlight the fact that fresh water bodies all over the world are becoming increasingly polluted day by day and that this represents a growing problem in the developing world and beyond. They suggest that regular monitoring is crucial for the well-being and health of the surrounding population and as such, the team has carried out a systematic study to estimate the physico-chemical parameters and level of toxic heavy metal content in the Jail Talav and Kalwa Lakes of Thane City, as perhaps being indicative of similar problems with other bodies of water.

The team’s measurements suggest that the presence of heavy metals such as iron, copper, nickel and zinc, which are essential for life at trace levels are well above permissible concentrations making them a significant threat to ecosystems and a problem for those who rely on the lakes for drinking water or crop irrigation. In addition mercury, arsenic and cadmium were all present at much higher than acceptable concentrations.

South Asia is home to more a fifth of the world’s population, the researchers say, and is facing a serious water crisis. “This region, which is in the grip of flood and drought cycles, needs a long-term strategy for management of its water resources,” the team says. Unfortunately, strategies adopted so far have all failed in India, the team asserts, this is obvious given the poor quality of the water revealed by their measurements of Jail Talav and Kalwa Lakes assuming these are typical of the region as a whole.

Food chain contamination by heavy metals has become an important issue partly because of the potential accumulation in biosystems, through contaminated water, the team adds. “A better understanding of heavy metal sources, their accumulation in water and the effect of their presence in water on plant systems are particularly impertinent in ongoing risk assessments,” the researchers say.

Singare, P., Naik, K., & Lokhande, R. (2011). Impact assessment of pollution in some lake water located at and around Thane City of Maharashtra, India: physico-chemical properties and toxic effects of heavy metal content Interdisciplinary Environmental Review, 12 (3) DOI: 10.1504/IER.2011.041819

Biofilters cut old landfill carbon footprint

Researchers in the US are testing biofilter systems as a viable alternative to releasing methane from passive landfill vents into the atmosphere. The technology could reduce the overall impact of old landfills on global warming. Details are reported in the current issue of the International Journal of Environmental Engineering.

Organic matter rotting in smaller, old landfill sites generates a slow trickle of the potent greenhouse gas, methane, into the atmosphere, amounting to just 2 or 3 kilograms per day per vent. In contrast to controlled methane generate for biofuel from modern, managed landfills, tapping this slow stream of the gas is not viable technologically or economically. However, methane has an infrared activity 21 times greater than carbon dioxide and so represents an important anthropogenic source of this greenhouse gas when attempting to balance the climate change books. Indeed, landfills contribute 12% of worldwide anthropogenic methane emissions due to the decomposition of organic waste.

Old landfills typically have passive gas vents. Methane is simply released into the atmosphere from these vents, or if the rate of emission is high enough it can be burned, or flared. According to Tarek Abichou and Jeffery Chanton of the Florida State University, Jose Morales of Environmental and Geotechnical Specialists, Inc., Tallahassee, Florida and Lei Yuan of Geosyntec Consultants in Columbia, Maryland, methane oxidation has recently been viewed as a more benign alternative to venting or flaring of landfill methane.

The researchers tested two biofilter designs capable of oxidizing methane gas to carbon dioxide and water. Both are packed with so-called methanotrophic bacteria, microbes that digest methane. They found that the radial biofilter design gave a much higher methane oxidation rate than a vertical biofilter. The higher surface area exposed to methane flow led to greater oxygen penetration into the biofilters, essential for microbial digestion. The radial biofilter has a surface area of well over 1.2 square meters whereas the vertical biofilter amounts to just 0.3 square meters area.

The team also found that the average percent oxidation rate of 20% and higher for the radial biofilter was possible when the air temperature was 20 to 36 Celsius, indicating the optimal soil temperature for methanotrophic bacteria to oxidize methane. Vertical biofilters averaged a little over 12% oxidation.

Abichou, T., Yuan, L., Chanton, J., & Morales, J. (2011). Mitigating methane emissions from passive landfill vents: a viable option for older closed landfills International Journal of Environmental Engineering, 3 (3/4) DOI: 10.1504/IJEE.2011.041354