The Nuclear Decommissioning Authority

 Although Trawsfynydd lies outside Arfon, a number of employees working on the site live in Hywel's constituency.

The seat is situated between the two constituencies that are home to Wylfa (Ynys Mon) and Trawsfynydd (Dwyfor Meirionnydd).

Hywel is a member of the House of Commons Science and Technology Select Committee.

His first viewing of the site took place when he was a schoolboy more than 40 years ago.

After visiting the ILW processing plants and one of the safestore buildings, Hywel said: "Trawsfynydd has been part of our landscape for decades and one tends to pass it without a thought.

"Indeed, the very long-term nature of the project tends to mask the extensive work that is continuingly going on there.

"On my visit I was impressed by the care and inventiveness of the work being done at the site, and the obvious commitment of the workforce.

"Part of the task appears just to be straightforward construction and demolition. However this is combined with novel work requiring the utmost delicacy and attention to detail.

"I am very glad to have had the opportunity to revisit Trawsfynydd after all these years!"

The visit was hosted by Site Director Dave Wilson and joined by Interim Chair of the Snowdonia Enterprise Zone John Idris Jones.