Tuesday, May 31, 2011

malaysiakini: Lynas RIA: Public 'safe' from radiation... by Joseph Sipalan

Lynas RIA: Public 'safe' from radiation
Joseph Sipalan
malaysiakini, May 30, 2011, 4:50pm

Authorities today released a radiological impact assessment (RIA) on the Lynas Advanced Material Plant (Lamp), which declared the project as safe, just as an international review panel went through its second day of study into Lamp's safety aspects.

The RIA, put on a month-long public display today, together with the project's environmental impact assessment (EIA), says the plant's operations "would not cause undue radiological risk" to the public and its future workers.

The report - carried out by national nuclear agency Nuklear Malaysia - says the public will receive zero mili-siverts (mSv) of radiation from the plant, while workers will receive an average of 13 mSv of radiation annually for the first 10 years of the plant's operations.
What this means is that the people should not encounter any radiation other than that already present naturally in the environment surrounding the Lamp, while workers will face levels far below the danger threshold of 50 mSv per year.

"Based on the results of the (RIA), it is concluded that operation of the plant will not (cause) any radiological risk to the workers and members of the public living in the surrounding areas of the site beyond what is allowed by the regulatory authority," the report says.

The report highlights seven “exposure scenarios” where radiation contamination could potentially happen, but says there will be little to be worried about, even in a worst-case scenario.

The exposure scenarios cover shipment transfer at Kuantan Port, transport from the port to the plant, exposure from stockpiles, processing equipment, residue storage and discharge of gas and liquid effluents.

'Negligible exposure'
In the various exposure scenarios outlined in the report, the RIA says the collective dose of radiation will be negligible for workers – who will have far greater proximity to the raw material and waste products – and have even less of an effect on the public.

In one worst-case scenario, where a truck transporting raw materials between the Kuantan Port and the facility tips over, the report estimates that radiation exposure would be around 0.01 mSv per hour at a distance of one metre from the materials.

“If cleaning work requires a single person to spend five hours, the estimated total dose received is still very small, i.e. 0.05 mSv,” the report says.

The internationally accepted public exposure level is 1 mSv per year.
Factoring in Lynas' plan to use clay and plastic-lined temporary storage cells to store waste on-site and industry standard methods to treat waste water and gas emissions, Nuklear Malaysia is of the opinion that the waste produced will have little or no impact on public radiation exposure.

Radon and thoron contamination readings at about one kilometre from the plant will be “very low”, at 0.02 micro-Sv per year and two micro-Sv per year respectively, the report says.

The RIA also says the people will not suffer any increase in radiation exposure by drinking water or eating fish from the nearby Balok river system, despite plans to release treated waste water from the plant into the river.

An estimated 5.1 million litres of treated waste water will be released into Balok daily – enough water to fill more than two Olympic-sized swimming pools every day.

The plant will also release around 478,800 cubic metres of gas emissions into the atmosphere over a decade of operations, a sufficient volume to send at least 217 four-man hot air balloons soaring in the sky.

Nothing finalised yet
Though Nuklear Malaysia gives a relatively glowing assessment of the proposed Lynas plant, it emphasises at the end of its report that the report should be revised as and when more operational data become available.

It noted that this is to make sure the estimated doses obtained in the current assessment can be further refined and that “the conclusion derived from this assessment is indeed realistic and acceptable”.

The report points out that it is “very important” to use site-specific data to get a realistic estimate of radioactivity from the plant, but acknowledges that site-specific data is “not readily available” – leading to their decision to use “default values” obtained from generic data sets “recommended internationally and they have been designed to give conservative dose overestimate(s).”
Nuklear Malaysia recommends that the input data and information on the report be updated and finalised, “in particular, the radioactivity content of the lanthanide concentrate materials and WLP (water leach purification) residue and water discharges.”

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