What is happening at Hartlepool Power Station?

Hartlepool Nuclear Power Station has been placed under additional scrutiny by the industry's regulator.

The Office for Nuclear Regulation (ONR) increased the plant's official attention level for safety meaning EDF, the site's operator, will have to make improvements.

The regulator said the site, which houses two nuclear reactors, remains safe to operate so will still produce electricity for the UK grid.

But the heightened regulation has meant the power plant has had to come up with a plan to improve its performance.

The Office for Nuclear Regulation is the UK's independent regulator for the nuclear energy sector.

It is tasked with overseeing nuclear safety, civil nuclear security, safeguards and conventional health and safety at 36 licensed nuclear sites.

It also regulates the transport of civil nuclear and radioactive materials by road, rail and inland waterways.

Explaining its role on its website, the ONR states its rules ensure "civil nuclear material remains accounted for and controlled" so the UK keeps its international obligations.

The ONR assigns power stations with an official attention level based on its performance in certain areas.

The attention levels range from Level 3, which is the lowest risk level, to Level 1 and plants are given a rating for safety, security, safeguards and transport.

The Hartlepool site has gone from Level 3 to Level 2 - enhanced regulatory attention in the safety category.

According to the ONR, a power station can be placed in Level 2 if it has been found to have had:

• An increasing level of risk or hazard profile in the licensee's undertakings
• Recent formal enforcement activity, particularly of a repeated nature
• Challenging and complex assessment issues that require enhanced specialist inspector attention
• Emergent or long-standing safety issues and/or the risk associated with the facilities in question

The ONR said the site needed to improve in three areas.

These are conventional health and safety, the number of site incidents and the production of nuclear safety cases.

A nuclear safety case is a body of evidence put together by the power station to demonstrate the safety of a nuclear facility and show risks are reduced to as low as reasonably practicable.

However, the regulator said the power plant was still safe to operate.

Hartlepool Power Station director Mark Lees said: "We have always worked with the ONR to address, and flag, technical issues as they emerge and to ensure they are content with the way we're working.

"Our action plan will ensure we continuously improve our performance on those issues identified by ourselves and the regulator."

The power station will now undergo additional inspections focusing on the areas flagged by the regulator.

Once inspectors believe enough improvements have been made, the site's attention level will be changed.

The ONR has not given EDF a deadline to make the improvements, but said it expects the company's plans will create a "positive and lasting change at the site".

An ONR spokesperson said: "EDF has stated it will actively progress the improvements requested and we do not believe any further action will be required to bring about the necessary improvements."

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