The maintenance workers who are members of union Unite, and employed under the terms of the NAECI blue book agreement, took prolonged strike action late last year for a rise in bonus payments to offset soaring inflation rates.

The three subcontracted firms that refused to implement bonuses last year were Jenkins and Davies, Altrad Engineering and Altrad support services.

Under the agreement, the workers have now secured an increase in bonus payments worth £2.06 an hour.

For a skilled worker, this works out as a pay increase of 10.6%, while for the lowest paid apprentices the increase is worth 24.5%.

In addition, workers were unhappy that the bonus was not normally paid during outages and slowdowns, however the employers have agreed to negotiate a new supplementary agreement to cover such events.

While the Valero dispute has been concluded, there are ongoing national negotiations to resolve similar disputes affecting other NAECI sites.

If those talks decide a higher bonus payment should be made than the Valero workforce will receive the higher amount.