1. City will backwash and drain filter tanks 1 and 3 prior to agreed start date and time. a. Tanks 1 and 3 are detailed by attached Diagram A. b. Tank are approximately 9 feet 6 inches X 7 feet 6 inches X 12 feet deep. Contractor responsible for verifying tank dimensions for bid. 2. Contractor will provide two (2) weeks’ notice of start date prior to mobilization. a. Project will be completed by April 30, 2026. b. Hours of work are flexible and subject to agreement with City. c. $100 per day liquidated damages will be deducted for each day Tanks 1 and 3 are not available for service after April 30, 2026. 3. Contractor will remove and City will dispose of existing filter media. a. Contractor will power wash the inside of each filter cell. 4. Contractor and City will inspect walls of tank to confirm areas of abrasive blasting. 5. Contractor will provide and install containment for Tanks 1 and 3. 6. Floor, troughs, and piping inside tank 1 and 3 will be protected. 7. Contractor will abrasive blast walls. a. Surfaces will be prepared to coating manufacturer requirements b. Contractor will clean surfaces to be free from all dust, debris, and latency. 8. Contractor and City will inspect walls to confirm any repairs needed 9. Contractor will fill pinholes, pitting, and voids with epoxy a. Epoxy will be epoxy modified cementitious mortar subject to City approval. Submittal and approval required prior to use. b. Epoxy will be Tnemec N218 Mortar Clad or equivalent. 10. Contractor to prime and then paint tanks 1 and 3. a. Paint will be 25-30 mils DFT subject to City approval. i. Paint Color to be Plain White - Submittal and approval required prior to use. b. Coating will be Tnemec Series 22 Epoxiline or equivalent. 11. Contractor will inspect underdrains. a. Contractor will repair any failed pipe or damage. b. Contractor will drill each plugged orifice hole that is located in each filter main and laterals. 12. Contractor will place filter media a. Contractor will order, procure, and provide media needed for project that may be needed in addition to, or that are used in place of City stored materials. b. Media required are detailed by attached Diagram B. c. Each layer will be placed and leveled prior to placement of the next layer. For sizes (1/2") and smaller, workers shall perform all duties while working off walk boards as per AWWA b100-01 Standards 13. Contractor and City will coordinate to backwash media a. Contractor will perform all required skimming operations before and after installation of media.
