T E C H N I C A L M E M O R A N D U M 135-11 ARLINGTON EAST WRF INFLUENT CHANNEL 135-11 Arlington East WRF Influent Channel Rehabilitation - Final PREPARED FOR: PREPARED BY: JEA Capital Budget Planning David Kowalski DATE: 2/4/15 Updated Bill Clendening 5/18/16 Introduction & Background The Arlington WRF headworks influent structure was constructed in 2000. The headworks structure has a vertical channel with a roof over it and then discharges to a channel that flows through fine screens and then flows out through a channel and then continues with underground piping to splitter box number 1. The roof of the structure and the channels that convey the sewage through this area are the subject of concern. These channels are exposed to high levels hydrogen sulfide gases(1000 ppm) that are generated by the sewage has deteriorated these structures over the years and are in need of repair. Justification The channels that convey the sewage through the headworks structure have deterioration due to hydrogen sulfide gases that produce sulfuric acid which has damaged and deteriorated the concrete. The amount of deterioration to the roof is unknown as there is no access to this area because of continuous flow and there is no bypass around the structure. The channels that can be inspected have deteriorated due to sulfuric acid attack caused by hydrogen sulfide gas. If these channels are not repaired and coated with an acid resistance coating there may be failure of the concrete and raw sewage spilling onto the ground and possible structural failure in the future. Scope The scope of this project is to rehabilitate the influent and effluent channels of the headworks structures. This involves bypassing the plant flows from the influent pump station to the aeration tanks in order that the channels that normally convey the sewage can be repaired. The work includes the installation of line stops and bypass piping on the influent force mains in order that the plant can still operate properly. Replacing the 54 header pipe with valves for future bypass efforts. The work also includes concrete repair and the coating of the channels with an acid resistant coating (Spectrashield). The scope of work includes but is not limited to: Design of temporary bypass system to divert flow around the headworks structure. Installation of line stops on force mains and temporary bypass pumping. Remove And Replace approx. 50 of 54 DI header pipe including (2) 54 valves.
Structural repair of the damaged concrete. 135-11 ARLINGTON EAST WRF INFLUENT CHANNEL Application of an acid resistant coating on the influent/effluent channels and roof of the headworks structure. Remove and replace six (6) sluice gates and seals in existing frames Implementation Schedule FY 2016 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Engineering Design Duration = 210 days Procurement Bid Duration = 150 days Construction Duration = 120 days Closeout Duration = 0 days FY 2017 Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Engineering Design Duration = 0 days Procurement Bid Duration = 60 days Construction Duration = 300 days Closeout Duration = 30 days Project Management & Delivery Stage Project Definition 10% Schematic Design 30% Conceptual Design 90% Detail Design 100% Final Design Bid Construction To Project Delivery W&WW PEC PEC PEC PEC PEC PEC OPB Established Trend Trend Trend 2
Cost Estimate and Expenditure Forecast ACTIVITY/DESCRIPTION SUB-TOTAL TOTAL Contractor Direct Cost $600,000.00 Contractor Indirect Cost $180,000.00 Overhead & Profit -15% $90,000.00 Miscellaneous-General/Special Conditions $30,000.00 Supplemental Work Allowance -10% max $60,000.00 JEA Cost & Engineering $156,000.00 Engineering $78,000.00 Project Management $39,000.00 Services During Construction $39,000.00 Real Estate $0.00 TOTAL PROJECT COST $936,000 PROJECTED EXPENDITURE FORECAST BY FISCAL YEAR ACTIVITY FY 2016 FY 2017 TOTAL QUARTER 1ST 2ND 3RD 4TH 1ST 2ND 3RD 4TH JEA Cost & Engineering 10% 3,900 $3,900 JEA Cost & Engineering 30% 23,400 7,800 3,900 $35,100 JEA Cost & Engineering Final 39,000 3,900 3,900 15,600 23,400 23,400 7,800 $117,000 Construction 78,000 312,000 312,000 78,000 $780,000 Project Closeout $0 TOTAL 3,900 62,400 11,700 7,800 93,600 335,400 335,400 85,800 $936,000 SIGNIFICANT MATERIAL SUMMARY DESCRIPTION UNIT MEASURE QUANTITY CONSTRUCTION 3
Risks: Possible structural failure in the future and raw sewage spilling onto the ground. Revision History Name Date Version Revision Notes 4
CP: Revision #: Date: Scope Approval The signatures below represent approval for this project. The groups represented must approve in writing changes to the scope, cost, or schedule, prior to implementing those changes. Corporate Planning Date O&M Date Outreach Date Environmental Date Others Signature Date Others Signature Date Rev 1 Description: Schedule Effect: Cost Effect: Approvals: Corporate Planning Date O&M Date Outreach Date Environmental Date Others Signature Date Others Signature Date Rev 2 Description: Schedule Effect: Cost Effect: Approvals: Corporate Planning Date O&M Date Outreach Date Environmental Date 5
Others Signature Date Others Signature Date 6