PLANS to begin reprocessing nuclear waste at Hinkley point, just 14 miles across the sea from Barry Island, pose "a direct threat" of increasing levels of radioactivity in Barry a marine consultant has warned.

When plans were approved for Britain's first new nuclear reactor in 18 years to be built at Hinkley Point, Somerset - which can be seen from Barry Island on a clear day - environmental groups reacted with concern.

However, expert Tim Deere-Jones says that equally concerning are plans to reprocess nuclear waste from Hinkley's decommissioned reactors. The liquid waste would be discharged into the Bristol Channel delivering what Mr Deere-Jones calls "significant quantities of radioactivity" to Barry and south Wales.

Environmental groups reacted with anger when Magnox began this process in Bradbury, Essex earlier this year - and according to reports the company have plans to do the same at Hinkley Point.

A May 2013 report by the Nuclear Decommissioning Authority states that their preferred option for getting rid of radioactive waste from Hinkley is not to ship it out to existing locations, and goes on to explain that "it makes sense" for the waste to remain where it is for reprocessing, although official planning permission is yet to be sought.

Magnox have stated that reprocessing waste from decommissioned power stations is safe, stating that liquid wastes are "discharged within authorised limits, which is a process that has been safely undertaken for more than 50 years."

A freedom of information request to Magnox, submitted by Tim Deere-Jones, shows that this liquid contains at least 21 radioactive materials, including plutonium and americium which emit alpha radiation - dangerous if ingested or inhaled.

Mr Deere-Jones said: "Because dominant Bristol Channel currents carry discharges eastwards along the Somerset coast, cross the Bristol Channel between Bristol, Barry and Cardiff, and then travel westwards along the entirety of the south coast of Wales, the radioactivity is readily available for transport into south Wales coastal regions.

"As result of the various mechanisms of sea to land transfer, south Wales coastal populations both close to and distant from the proposed Hinkley reprocessor will be exposed to multiple pathway doses of sea discharged radioactivity.

"These doses will be in addition to those already received from the long term historic marine radioactive discharges of the multiple nuclear sites on the Bristol Channel and any further future doses from the proposed new reactors at Hinkley."

Mr Deere-Jones went on to explain that sea to land transfer of radioactive materials can occur due to high tides and storm surges, adding that such events have been recorded depositing hundreds of tonnes of radioactively contaminated marine sediments into Welsh coastal environments.

He said: "Although marine discharged radioactivity initially dilutes, in the longer term there are a number of mechanisms by which it re-concentrates in marine environments."

A study in west Wales showed that radioactive elements discharged into the sea could later be found 10 miles inland in grass, having become highly enriched in sea spray due to onshore winds.