nuclear-news

Energy Northwest nuclear plant failed to properly measure workers’ radioactive exposure, report says

KPVI, Annette Cary Tri-City Herald, Jun 7, 2023 

Energy Northwest failed to correctly measure the exposure of workers who inhaled or ingested radioactive material during an incident at the Northwest’s only commercial nuclear power plant, said the Nuclear Regulatory Commission.

On the night shift during the spring refueling and maintenance outage two years ago, some workers received unexpected and significant exposure to radiation, according to the initial report by the NRC.

The NRC issued a “white finding” last week and said it is considering issuing a second white finding after workers were exposed to radiation May 28, 2021, at Energy Northwest’s Columbia Generating Station nuclear power plant, according to documents made public Monday.

A white finding, the second lowest on NRC’s four-step color scale, has low to moderate safety significance and can lead to an additional NRC inspection to make sure issues have been corrected.

The notice of the first white finding was for three violations in the incident — failure to the control the concentration of radiation material in the air, failure to control the activities in a high radiation area and failure to survey areas to evaluate the extent of radiation levels.

But while investigating the incident at the plant near Richland, Wash., the NRC also began questioning whether Energy Northwest correctly measured the internal radioactive exposure of the workers…………………………………………………………………….

Radiation readings ‘off-scale high’

The updated NRC information says that as the two pipefitters left the heat exchanger room, they were frisked by radiation protection staff “and the instrument readings went off-scale high.”

They were then escorted to personnel contamination monitors, which alarmed, indicating there was radioactive material on or in the workers.

After multiple showers and scans on the personnel contamination monitors, Energy Northwest confirmed they had internal uptakes.

The two workers were sent to initiate the whole-body count process, with initial counts confirming they had inhaled or ingested cobalt 58 and cobalt 60 radionuclides.

However, there was indication from checking the pipe that was cut that plutonium 239 and plutonium 240 contamination was possible in the incident, but that information was not used to assess workers.

Energy Northwest’s procedures for internal dose assessment were incomplete, failed to provide clear directions and did not fully address all radionuclides that could have contaminated the workers, according to the NRC report.

Dose is a measure of the amount of radiation absorbed that accounts for the type of radiation and its effects on particular organs.

The two pipefitters had their urine tested only once and no fecal samples were collected.

“In conclusion, not only did the licensee (Energy Northwest) fail to implement the most appropriate sampling methods to detect the level of hard-to-detect radionuclides from the intake, including alpha emitters, but they did not take any additional samples to suitably establish trends and elimination rates of these radionuclides,” according to the most recent NRC inspection report.

Energy Northwest also failed to effectively take air samples in the workers’ breathing space during the incident, the NRC said.

Not only were procedures inadequate, but Energy Northwest did not have the equipment or personnel available to address the level of contamination and assess the dose within workers bodies, according to the NRC report………………… https://www.kpvi.com/news/national_news/nw-nuclear-plant-failed-to-properly-measure-workers-radioactive-exposure-report-says/article_820def90-c6b4-581a-a989-708339c2c32e.html

June 8, 2023 - Posted by Christina Macpherson | USA, women