India neutrino lab dealt a serious blow

NEW DELHI—India’s plans for a world-class neutrino facility have hit a serious roadblock. Regulators this week directed the India-based Neutrino Observatory (INO) to seek new environmental permits, pushing the long-delayed facility’s completion further into the future—and further jeopardizing its hopes of making an important discovery.

Perhaps the most expensive basic science project India has ever contemplated, the $220 million INO would be installed deep under a mountain in southern India. It aims to solve the neutrino mass hierarchy: to determine, that is, which of the three types of neutrinos is heaviest and which is lightest. That arcane knowledge would allow physicists to probe long-standing mysteries such as how neutrinos acquire mass and why the universe has so much more matter than antimatter.

Indian physicists originally hoped to have the INO up and running by 2012. That target evaporated in 2009, when India’s environment ministry denied permission to construct the INO on the edge of prime elephant habitat in Tamil Nadu state. The project team then found an alternative site in the Bodi West Hills, also in Tamil Nadu. Prime Minister Narendra Modi approved the INO in January 2015, and a new completion date was set for 2020.

Work stalled again in March 2015, when a court ordered the INO project team to seek a pollution control permit. Critics claim that blasting rock to carve the observatory’s access tunnel and experimental hall would disrupt local ecology, including in nearby Mathikettan Shola National Park. “We are seriously concerned about the impact of the project on the fragile ecology and water sources of the biodiversity-rich Western Ghats,” says Gomathinayagam Sundarrajan, an engineer and activist with Poovulagin Nanbargal, an environmental nonprofit.

Meanwhile, Sundarrajan in 2015 petitioned India’s National Green Tribunal to cancel the INO’s environmental permit. On Monday, the tribunal directed the INO to seek a new permit from the central government as well as get clearance from the National Board for Wildlife, which oversees Mathikettan Shola National Park, and put the project through another environmental impact assessment.

“The tribunal’s order will cause a serious delay in starting the project,” says INO project director Vivek Datar, a physicist at the Tata Institute of Fundamental Research in Mumbai. He says the earliest conceivable completion date is now 2022. That means the INO will fall further behind other facilities gunning for the neutrino mass hierarchy, including China’s Jiangmen Underground Neutrino Observatory, expected to open in 2019.

“We are highly demoralized,” says Naba Mondal, a physicist at the Saha Institute of Nuclear Physics in Kolkata, India. Mondal, who helped conceive the INO and until recently served as project director, fears the latest delay could make the observatory “irrelevant” in the quest to solve the neutrino mass hierarchy. Datar says the INO plans to comply with the tribunal’s ruling—and he does not rule out searching for a new site to build it.