Date | Jan 21, 2017:

Tummalapalle village in Andhra’s Kadapa district has been in the news for some time now as one of the world’s largest reserves of uranium. But new evidence suggests that the region holds much larger reserves than scientists had previously estimated.

The Times of India reported that the reserves are now estimated to stand at 1 lakh tonnes of uranium oxide. When they were first discovered it in 2000, the reserves were estimated to contain only 14,300 tonnes of uranium oxide, while the estimates were subsequently increased to 85,000 tonnes in 2014.

The report also stated that while previous research had only indicated uranium ore existing only up to a depth of 250 metres, the latest findings reportedly indicate that the reserves run as deep as 1,000 metres.

TOI also said that the extent of deposits of “carbon-hosted” uranium, could mean that the area could be profitably mined till beyond 2050.

The findings were discussed at a meeting by the Geological Society of India (GSI) at IIT Kharagpur, held in October last year.

Research suggests that the uranium deposits may have been mineralised during the Mesoproterozoic or Neoproterozoic era, which ranges from 1,000 to 2,000 million years ago.

Stating that the 'lodes', which are veins of metal ore in the earth, are narrow, the UCIL website goes on to add:

"A highly mechanised underground mine has been opened up using state of the art technology through three 9-degree declines. The central decline has a belt conveyor meant for transport of ore and the other two are meant for movement of men and machineries."

There is also a processing plant next to the mine, where the ore is converted into sodium diuranate, or yellow cake, which fuels nuclear power plants.

However, claims that the reserves may be the largest in the world, are not new. In fact, they have been around since 2011.

In 2011, Srikumar Banerjee, Secretary, Department of Atomic Energy, and Chairman of the Atomic Energy Commission had said, "Studies have already shown that the area had a confirmed reserve of 49,000 tonnes and recent surveys indicated that this figure could go up even three fold."

The mines were formally commissioned in 2012, when it was reported that it would alone cater to 25 percent of the uranium requirement for nuclear power plants in the country, once fully operational.

In 2012, Frontline visited the mine, and reported:

"At Tummalapalle, the host rock that contains natural uranium is dolomite, whose calcium-magnesium-carbonate content is high. Although the Tummalapalle deposit was discovered in 1986, UCIL could not mine and process the ore because of its complex nature."

Following several brainstorming sessions, the officials decided to crush and grind the raw ore that was mined, following which the uranium content was extracted by subjecting the slurry mixture to a leaching reaction.

The leaching reaction involved reagents such as sodium carbonate and sodium bicarbonate, which were added along with oxygen, to extract the desired product.

However, the mining isn't without controversy, as the villages around the mine have seen a steady decline in the quality of water and soil in the region.

In December 2016, it was reported that researchers from Jawaharlal Nehru Technological University (JNTU), Anantapur, analysed samples of water and soil, and detected heavy and trace metals.

"The increased levels of barium, arsenic, cobalt, chromium, copper, molybdenum, lead, vanadium and yttrium are a major concern for the suitability in agricultural and other land management practices," the researchers were quoted as saying.

The researchers had suggested regular monitoring of water and soil quality and plantation of more trees in the area, to prevent further deterioration of the soil and water quality.

(Source: https://www.thequint.com/)