In order to minimize the City of Cumberlands (City) risk, only proven products with substantial successful long term track records will be approved. All Contractors must be pre-approved prior to submitting a bid. Documentation for products and Contractors seeking pre-approved status must be submitted no less than 2 weeks prior to proposal due date. All required submittals must be satisfactory to the City. The following products are pre-approved and need not submit additional documentation: Insituform. The following Contractors are pre-approved and need not submit additional documentation: Insituform Technologies, Inc., Visu-Sewer, Michels Pipe Services, and Veit Specialty Contracting & Waste Management.