Neilly Group (NG) worked with SGM Environmental to detail surface water remediation required for a derelict mine site in NSW. The aim of this project was to improve surface water flows at the site and remove the potential for sediment to be transported during storm events. To determine appropriate remediation an investigation of the existing surface water flows needed to be undertaken. Establishing the existing conditions at the site helped to inform the concept and detailed design of the remediation works. The works designed included a sediment basin with inlet and outlet rock chute structures and a channel to reconnect existing disturbed flow paths. This design formed part of a larger Remediation Action Plan being prepared for the site by SGM Environmental.