Allerton TCC 331 Heavy Maintenance Feasibility

We propose to evaluate the possible infrastructure solutions at Allerton TCC for feasibility and option selection assessments as per the outline scope below:

• To evaluate and define optimal solutions for bogie drop, transfer, and storage facilities, as well as jacking systems and a potential shed extension, to support heavy maintenance operations for 3-car and 4-car Class 331 units, with future-proofing considerations.
• 3 car HM cycle is due March 2028 and the 4 car units will commence Jan 2029 this report will determine if there is potential for a phased approach to enable 3 car maintenance to be undertaken with 4 car requirements being constructed at a later stage, and if it should be foreseeable that its possible undertake 3 car maintenance cycle, whilst being able to complete the required construction works for 4 car unit facilities.
• The additional requirements for 4 car units to be maintained would be additional jacking equipment, shed extension to road 4 / 5 shed, foundations/pits and storage for the additional 4-wheel sets (2 old & 2 new)

This feasibility and option selection project will identify the optimum solution to each issue. The solution must be deliverable, operationally efficient, represent value for money and meet NTL strategic objectives.

The Selected option for each proposed scheme will form the work scope for the design phase. Completing this feasibility and option selection will allow the proposed schemes to commence at design stage, improving project delivery efficiency.