Debate: Can neutrinos have devastating impacts on local biosphere?

'There is no risk associated with neutrinos'

Naba K Mondal

Project director, India-based Neutrino Observatory (INO)

The study of neutrinos is one of the most exciting areas of research in basic science today, and we are competing with countries such as USA, Japan and China in this field. It is also a globally competitive science project, so the opposition was unexpected. Once it was discovered that neutrinos have mass, a more fundamental question emerged: the mass hierarchy of neutrinos. We plan to address this question in the proposed Mangetic Iron Calorimeter (ICAL) detector at INO. In the course of time, this underground facility will develop into a full-fledged science laboratory for studies in physics, biology, geology and hydrology.

The original site was in Singara, Nilgiri district, Tamil Nadu. But when the Mudumalai forest area was declared as a tiger reserve, which is close to our proposed site, we decided to shift the site to Theni district. This site was chosen after taking into account environmental and ecological factors, geological stability and physics requirements. It was originally identified by the Geological Survey of India.

The Salim Ali Centre for Ornithology and Natural History (SACON), Coimbatore, prepared the Environmental Impact Assessment (EIA) report for this project. Based on a series of presentations and discussions with experts from the Union Ministry of Environment, Forest and Climate Change and the Tamil Nadu State Environment and Forest Department, we received both the environmental and forest clearances.

After the project was approved in December 2014, a case was filed in the Madurai bench of the Madras High Court to stall the project. The court passed an interim order asking us not to commence work without getting clearance from the Tamil Nadu Pollution Control Board. We applied for this clearance in May 2015, and are awaiting their response.

There is no risk associated with neutrinos—either from naturally produced neutrinos or from factory produced neutrinos. Trillions of neutrinos, in fact, pass through our body every second without doing any harm to us. There will be no radiation, as we will study only atmospheric neutrinos produced by cosmic rays in our atmosphere. One of the reasons we plan to set up our experiment underground is to avoid any form of radiation due to cosmic rays.

While construction has not started, we are continuing our R&D to build an engineering prototype of the ICAL detector. Many students have already received their PhDs on the detector and related physics studies. Some of them are also working with other leading laboratories/universities in the world involved in neutrino research.

'Blasting will disturb and contaminate the hydraulic systems'

Sundarrajan and Vijay Asokan

Poovulagin Nanbargal, an association based in Tamil Nadu opposing the project

Nestled in the midst of the verdant Western Ghats, Theni is Tamil Nadu's pride. For over two years, people in a tiny village called Pottipuram in Theni have been living in unknown fear. Local people are opposing this project not because of "intolerance to science" or "ignorance", as scientists would allege, but because none of the scientists has come here to explain what is in store for them.

The Western Ghats is the birthplace of peninsular rivers and aquifers. Groundwater resources will be badly affected if the project is implemented. Also, the Western Ghats, where Pottipuram lies, has been declared by UNESCO as an ecologically sensitive area. The project area includes the Cardamom Hills in the Western Ghats, a UNESCO heritage site, near the Kerala-Tamil Nadu border. Even though 40 per cent of the project area covers places such as Idukki district in Kerala, the EIA team did not visit Kerala for their field study and they have not sought permission from the environment ministry in Kerala. The ecological impact assessment—it was not an environmental impact assessment—was done by an unaccredited agency, SACON.

Although the scientific community claims that there will be no negative impact on the aquifers and nearby dams due to the vibrations caused by blasting the rocks, it is important to note that the water in nearby streams or other surface waterbodies is connected hydraulically with the bedrock fracture system. Leaching of chemicals from blasting material is likely to interact with rock-water interfaces, which will impact the groundwater chemical composition. The change in composition could easily spread to nearby water streams and surface waterbodies.

There has been no effort to study the effect of nitrates or other chemical contaminants on groundwater or wells nearby. Studies related to possible human-made seismic events and possibility of tectonic fracturing during blasting should also be done and the local people must be given access to the documents. Also, there is no environmental monitoring group appointed by the government to do simulation studies considering the future environmental effects.

Experts say the shockwaves produced as a result of a blast are not preventable. The waves, whatever may be their strength, will certainly impact adjoining areas. At sub surface level, any disturbed geological structure can become highly unstable and no one has analysed how they will be affected.

The EIA report says: “The experts are hopeful that during its normal operation phase, the laboratory is not expected to cause any damage to the environment. However, there is no detailed study regarding the impact of blasting of a large quantity of rock on the aquifer, the rivers and the reservoirs in the Environment Impact Assessment.”

 

'There is no risk of radiation from neutrino detectors'

James Russ

Professor of physics, Carnegie Melon University, USA

First, let me assure you that neutrino experiments are a very high priority for science. There are two classes of neutrino experiments: neutrino properties and neutrino sources. The proposed INO belongs to the first category, aiming at precise measurements of the ways that neutrinos interact in material. The unique feature of INO is that it uses magentic deflection of the neutrino interaction products to gain more information about the events. This is different from the very large experiments (larger than INO) that are now running or under construction in Japan and the US. One can exchange magnetic deflection for precise tracking in large volumes.

Neutrinos are very elusive objects. They interact only weakly and they are not charged. So they interact with matter only when they collide, which is very rare. That’s why the detectors have to be large. The low interaction rate means that any other processes that produce muons—an unstable subatomic particle that makes up much of the cosmic radiation reaching the earth’s surface—in the detector, like cosmic ray interactions, can easily swamp the true neutrino signal. The way to suppress the cosmic ray background is to move the neutrino experiment into a cavern. The INO approach is the same as that in Japan—using a shaft in a mountain to create the cavern.

The US approach uses an abandoned gold mine, like the Kolar experiment in India. Because the neutrinos have no electric charge and interact only weakly, there is absolutely no radiation hazard from neutrino detectors. For the INO project, the neutrinos are produced in cosmic ray interaction far, far up in the atmosphere. No radiation from those interactions reaches earth.

Building a neutrino laboratory is a big project, and ecological concerns have to be addressed. One example of a successful project in a sensitive area is that of a cosmic ray experiment. In southern Utah, the Telescope Array detectors sit at the ground level in a desert area. Amerian Indians and other historical people lived in this region hundreds of years ago, and the experiment designers had to work with archeologists and ecologists to ensure that installing the detectors did not harm the environment and disrupt historical research. That was accomplished to the satisfaction of all.

The potential clash between science and special interests is not unique to India. If INO moves from studying atmospheric neutrino properties to probing accelerator-produced neutrinos, then many other issues become important. The production of neutrinos by accelerators requires very special equipment that has to be located with high precision in underground facilities that contain the radioactivity.

One of the concerns such projects should address is the possibility of groundwater contamination. There are many working accelerators around the world. The possibility of contamination from an accelerator is tiny. Nuclear power plants are more likely to produce radioactive contaminants than particle accelerators. The safety engineering to ensure contamination-free operation of a neutrino production facility is well-established.