Sellafield’s legal team said it will be seeking to recoup its costs from a former worker who claims she was sacked to silence bullying concerns.

At a Manchester Employement Tribunal hearing held remotely on Tuesday, the company’s solicitor Deshpal Panesar said this was due to confusion over which claims were being brought.

Employment Judge Marion Batten also heard claims that the Nuclear Decommissioning Authority (NDA) had attempted to close down a crowdfunding page which Alison McDermott, who submitted a whistleblowing and victimisation claim against the nuclear firms after she was sacked, was using to fund her legal fees.

Judge Batten heard that an application submitted by Mrs McDermott when she was acting for herself in February alleged that evidence had been fabricated, tampered and falsified, misleading the tribunal.

However Chris Milsom, for Mrs McDermott, said these submissions had now been superseded by a further application submitted by him on behalf of Mrs McDermott in June, which criticise the approach to disclosure of information by Sellafield, the NDA and Heather Roberts, who was in charge of HR at Sellafield when Mrs McDermott's contract was terminated.

Judge Batten said: “My understanding is that there were some very serious allegations made against solicitors involved. There were emails that almost amount, and I’m not sure I should use this term, to threats, certainly menacing, quoting professional conduct rules and saying: ‘I’m going to report you.’ That’s quite surprising and worrying.”

Mr Milsom said investigations by the Solicitors Regulations Authority were ongoing.

“As I understand it, the purpose of today, is not restoration of reputation of any adviser or representative.

“One can well understand the exasperation of the claimant in this case, the approach to disclosure of all three respondents has been woeful.”

But Mr Panesar, representing Sellafield Ltd and Ms Roberts said he only received confirmation that those allegations of fabrication and tampering were not being pursued by Mrs McDermott the night before the hearing.

He said: “I telephoned Mr Milsom during the day to ask whether the allegations of fabrication, tampering and falsification were going ahead.” He added Mr Milsom could not answer his question straight away.

Mr Panesar said: “He told me at 7.27pm that they weren’t proceeding with that.”

He added that the application made in June did not say it would supersede the February one, therefore due to the amount of work done by solicitors to prepare to answer those claims, he would be making an application for costs.

The court also heard that the NDA had looked into getting Mrs McDermott's crowdfunding page closed down, however advice received by the NDA determined attempts would be unsuccessful.

Mr Milsom said: "It's surprising to see a public body, given the nature of the claims, attempting to scupper the claimant's [Mrs McDermott's] access to funds that she needs to pursue her claim."

Rachael Levene, for the NDA, said: "In an attempt to raise money for her case, she has made various statements, those are a clear risk to the reputational damage of the respondent [NDA]. It's understandable that they would seek advice where there's a crowdfunding page making allegations, there's a danger these would be judged inappropriately."

The crowdfunding site shows that £20,760 was raised thanks to 146 donations.