E-CAMP - Encina Wastewater Authority

Figure S‐1.2.006ePrimary Influent Gate Guide CorrosionFigure S‐1.2.006fPrimary Influent ChannelThe following table summarizes the PSB components and current condition and observations:Facility ElementCondition DescriptionA. PSB Influent Channel Channel condition below the water level is unknown. The facility is notequipped with means of isolating the channel for inspection and maintenance.B. PSB Influent Gates Primary influent gate guide stems and shafts are corroded, and gates cannotbe used to isolate the basins. There are two influent gates for each primarysedimentation basins, for a total of 20 influent gates. Each gate was designedto seal an 18‐inch diameter opening.C. PSB Structures – general Cracks have been observed in Primary Sedimentation Basin (PSB) wallsbetween the basins, between PSB Nos. 2 and 3 in particular. When a PSB isisolated for maintenance, staff reports that cracks in the wall allow flow tomove from the full basin to the empty basin. Concrete damage observed onthe top of walls can also prevent covers from sealing, causing odors to bereleased. Additional testing is required to determine which tanks are damaged,extent of damage, such as corrosion of steel reinforcing.D. PSB 1‐6 Concrete Assessment video dated 10/2012 shows urethane coating over deterioratedconcrete on vertical walls and concrete damage 0.75 to 1‐inch deep at effluentstop plate locations.E. PSB 1‐6 Covers Covers were replaced in 2012.F. PSB 7‐10 Covers Covers are in acceptable condition.G. PSB 1‐10 Sludge and Scum Equipment has been in service approximately 15 years, which is typical serviceCollectorslife. Some flights and other parts have been replaced, as needed.H. Weirs and Launders No known deficiencies based on general observationI. Helical Skimmers The original skimmers were constructed of carbon steel with 15 year servicelife. The skimmers were replaced with stainless steel type. The skimmersappear to be in good condition but may require refurbishment of rotatingassemblies or seals.J. Scum conveyance Primary scum is conveyed to the primary influent gallery through an 8‐inchpipeline parallel to the drainline from MH‐4. Based on CCTV, settlement in thearea has impacted the drain pipeline and there is concern that settlement mayhave impacted the scum pipeline. Refer to Project P – 1.2.010 which addressesthe scum pipeline. Additionally, staff has recommended the automation ofscum flow control. Scum pumps are in acceptable condition and aremaintained through annual refurbishment.E FY2014 E‐CAMP Report 2012‐12Dec.docx 21 December 26, 2012