Ansaldo Nuclear gets to work on the SIXEP tie-in trials contract

Ansaldo Nuclear is no stranger to working on large-scale projects for Sellafield. This trend continued recently, with Ansaldo being awarded the SIXEP tie-in trials contract – the first contract under the Programme and Project Partners new goods and services agreement.

But what exactly will the project entail?

We sat down with Christopher Chew, C2 Engineer at Ansaldo Nuclear and Engineering Lead on the SIXEP tie-in trials project, to find out…

Firstly, what is SIXEP, and why is it so important to Sellafield?

SIXEP – or, to give it its full name, Site Ion Exchange Effluent Plant – is a filtration plant at Sellafield which has been in operation for a number of years. Think of it like the kidneys of Sellafield. Its ultimate purpose is to reduce the number of hazards which accumulate at the site over time, cleaning out any liquid effluents before discharging them to sea.

The plant is coming to the end of its life, which is why the Programme and Project Partners (PPP) at Sellafield is currently constructing the SIXEP Continuity Plant (SCP). SCP will continue to do the vital work of filtering Sellafield’s liquid effluents and keeping the site and surrounding environment safe for at least another 50 years. But, before that can happen, it needs to be ‘tied-in’ to the existing SIXEP facility.

What exactly has Ansaldo been contracted to do?

Our role is to plan a series of trials that will test and inform the design of the key connections that will ‘tie’ SIXEP and SCP together. While our main objective is to prove the efficacy of the solution we provide through vigorous product trials, the ultimate goal is to implement a solution with minimum disruption to the Sellafield site. That means Ansaldo Nuclear will be involved from inception right through to installation.

What are some of the unique challenges Ansaldo will need to overcome during this project?

The tie-in project presents three relatively unique challenges, the first of which concerns planning. The SIXEP facility was never originally designed for these tie-ins, and a lot of the plant information only exists on legacy databases. Although the facility has been inspected, there are some things we just don’t know, which means the solution is going to have to be flexible enough to conform to certain aspects that we can't yet fully define.

The second challenge is a case of logistics. The tie-in will be located in a particularly awkward part of the plant, around two metres down an extremely restricted access hole. Not only does that make the installation harder, it’s also made inspection very difficult.

Finally, this is very much a ‘one shot’ project. The SIXEP facility will have to be shut down while the installation is completed, for which we have a limited time window of around 100 hours. For that reason, preparation will be key to success. We have to ensure all the timings are right, and that the solution is fit for purpose.

The combination of those challenges means we can’t draw upon ‘as-built’ parts or solutions. But there's a lot of scope to find unique solutions for the problems presented, so it’s a challenge we engineers relish.

Why was Ansaldo Nuclear the right choice for such a crucial project?

The SIXEP tie-in trials contract is just the latest in a number of nuclear R&D projects that Ansaldo has been awarded. Beyond that, we have a proven track record of delivering large scale projects to Sellafield in a collaborative manner. Sellafield demands more than just a transactional approach. Their stakeholders want to work with companies that will engage with them every step of the way in order to arrive at the best solution possible.

The other key advantage Ansaldo brings is a comprehensive in-house capability. Ansaldo Nuclear can offer everything in-house – design, manufacturing and (in particular) testing. The testing facilities we have on-site enable us to better represent the final environment that we're going to be installing into, which is both enclosed and below ground. The better we can simulate this final environment, the better we can prove the credibility of the solution beyond doubt.

How important will the theme of collaboration be to the success of this project?

With the number of companies working on various projects across the Sellafield site, collaboration is crucial. It helps facilitate more open communication, and it minimises the unnecessary hurdles which can get in the way of progressing a project. We've already had visibility over the different suppliers working on other projects, and it’s really helped develop relationships in a more productive way. Because we can engage with those suppliers easier, we can get our job done easier as a result.

We're currently in the mobilisation phase, and we expect to start manufacturing and testing designs shortly. We’re really looking forward to developing and delivering another cutting-edge solution to Sellafield, and showcasing our R&D credentials even further.

You can find out more information about the SIXEP tie-in trials contract from the link below:

https://www.gov.uk/government/news/new-contract-will-support-sellafield-facility-for-decades-to-come