Paradise Irrigation District Process Water Recycling Project Life Cycle Cost Analysis Report

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1 Paradise Irrigation District Process Water Recycling Project Report Project Number: July 2014 Paradise Irrigation District George Barber, General Manager AECOM Joseph Huang, PE, Project Manager 2020 L Street, Suite 400, Sacramento, CA 95811

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3 Table of Contents Table of Contents Executive Summary... 1 Section 1 Introduction and Background Background Cost Analysis Assumptions... 3 Section 2 Alternative 3 Mechanical Settling Description Dewatering Annual Costs Life Cycle Cost... 9 Section 3 Constructed Wetlands Option Site Description Permitting Scope of Facilities Annual Costs Life Cycle Cost...20 Section 4 Summary and Conclusions Comparison of Life Cycle Costs Non-Monetary Considerations Recommended Project...28 Process Water Recycling Project i

4 List of Tables Table ES-1. Life Cycle Cost Comparison...ES-3 Table ES-2 Summary of Advantages and Disadvantages...ES-4 Table 1-1. Cost Analysis Assumptions... 4 Table 2-1. Alternative 3 Mechanical Settling Design Criteria... 6 Table 2-2. Belt Filter Press Preliminary Design Criteria... 7 Table 2-3. Centrifuge Preliminary Design Criteria... 8 Table 2-4. Alternative 3 Annual Cost Summary... 9 Table 2-5. Alternative 3 Life Cycle Costs...10 Table 3-1. Wetlands Option Site 3 Design Criteria...19 Table 3-2. Wetlands Option Site 3 Annual Cost Summary...21 Table 3-3. Wetlands Option Site 3 Life Cycle Cost...21 Table 4-1. Life Cycle Cost Comparison...27 Table 4-2. Summary of Advantages and Disadvantages...28 Process Water Recycling Project ii

5 List of Figures Figure ES-1. Existing Treatment Plant Flow Diagram... 1 Figure ES-2. Mechanical Settling Plant Flow Diagram... 2 Figure ES-3. Constructed Wetlands Flow Diagram... 2 Figure 1-1. Existing Treatment Plant Flow Diagram... 1 Figure 1-2. Mechanical Settling Plant Flow Diagram... 2 Figure 1-3. Constructed Wetlands Flow Diagram... 3 Figure 2-1. Alternative 3 Process Flow Diagram...11 Figure 2-2. Alternative 3 Site Plan Figure 2-3. Alternative 3 Site Plan Figure 3-1. Wetlands Option Site 3 Process Flow Diagram...23 Figure 3-2. Wetlands Option Site 3 Site Plan...25 Appendices A. Alternative 3 Mechanical Settling Detailed Opinion of Probable Construction Cost B. Wetlands Option Site 3 Gravel Filter Detailed Opinion of Probable Construction Cost Process Water Recycling Project iii

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7 Executive Summary This study presents a life cycle cost comparison of two Alternatives for recycling water from the adsorption clarifier flush water, filter backwash water, and filter to waste water from the Paradise Irrigation District (PID) Water Treatment Plant (WTP). Currently these flows are gathered in storage ponds, where the clarified water is decanted and discharged to Magalia Reservoir, see Figure ES-1. Because of this discharge, PID maintains a National Pollutant Discharge Elimination System (NPDES) Permit through the California Central Valley Water Quality Control Board (Regional Board). The current Permit expires in Raw Water Storage Tank WW EQ Tank Sludge Ponds Solids to Landfill Raw Water Pump Station Adsorption Clarifiers Filters Treated Water Tank Distribution Magalia Reservoir Figure ES-1. Existing Treatment Plant Flow Diagram Recycling these flows allows PID to let the permit expire, with the added benefit of saving water. Two previous reports, prepared by Lee & Ro and Brown and Caldwell studied four Alternatives for recycling these flows and narrowed the options to two, herein referred to as Alternative 3 and the Wetlands Option Site 3. The two Alternatives are: Alternative 3: Flocculation and sedimentation of the wash water stream clarification sized to equalize flush water from the clarifiers. Wetlands Option Site 3: Reconstruction of the existing North and South Sludge Ponds and constructing a gravel filter (constructed wetland ). Alternative 3, shown in Figure ES-2, recommended installing the following facilities sized for flow of 6.3 million gallons per day (mgd): Flocculation basins High rate sedimentation clarifiers with tube or plate settlers Mechanical dewatering of residual solids Washwater return pump station Yard piping to accommodate the new processes Process Water Recycling Project ES-1

Floc Basins Clarifiers Raw Water Storage Tank WW EQ Tank Dewatering Solids to Landfill Raw Water Pump Station Adsorption Clarifiers Filters Treated Water Tank Distribution Magalia Reservoir Figure

8 Floc Basins Clarifiers Raw Water Storage Tank WW EQ Tank Dewatering Solids to Landfill Raw Water Pump Station Adsorption Clarifiers Filters Treated Water Tank Distribution Magalia Reservoir Figure ES-2. Alternative 3 Plant Flow Diagram The Wetlands Option Site 3 includes the following: Reconstruction of the existing North and South Sludge Ponds Refurbishment of the existing wash water return pumps Installation of a constructed wetlands (gravel filter) Yard piping to accommodate the constructed wetlands Construction of a Sludge Drying Bed to increase drying capacity of the plant. Solids to Landfill Sludge Drying Bed Sludge Ponds Raw Water Storage Tank WW EQ Tank Wetlands / Gravel Filter Raw Water Pump Station Adsorption Clarifiers Filters Treated Water Tank Distribution Magalia Reservoir Figure ES-3. Wetlands Option Site 3 Flow Diagram Table ES-1 compares the life cycle costs between the mechanical settling and gravel filter option. Because of the large capital costs of the Wetlands Option Site 3, its life cycle cost is over 60% greater than that of Alternative 3. Process Water Recycling Project ES-2

9 Table ES-1. Life Cycle Cost Comparison Cost Item Alternative 3 Mechanical Settling Wetlands Option Site 3 Capital Cost $5,100,000 $8,900,000 Contingency (30 percent) $1,500,000 $2,700,000 Subtotal $6,600,000 $11,600,000 General Conditions (10 percent) $660,000 $1,200,000 Subtotal $7,300,000 $12,800,000 Overhead and Profit (15 percent) $1,100,000 $1,900,000 Subtotal $8,400,000 $14,700,000 Escalation to Mid-Point of Construction (6.1 percent) $510,000 $900,000 Total Capital Cost $8,900,000 $15,600,000 Annual Cost Present Worth $850,000 $730,000 Total Life Cycle Cost $9,800,000 $16,400,000 Note: The cost estimates are provided for budgeting and comparative purposes and represents a planning-level effort based on our best knowledge of current bid climate and installed costs for similar projects. Additional project details identified during planning, preliminary engineering, and design may increase or decrease the opinion of probable construction cost. Although the life cycle cost analysis heavily favors Alternative 3, non-monetary factors should also be considered when selecting the preferred Alternative. A summary of non-monetary benefits for both Alternatives is presented in Table ES-2. Based on the comparison of the non-monetary factors considered above, including impact to space, operations, and flexibility, Alternative 3 is preferred. Recommended Project The Wetlands Option Site 3 alternative is not financially viable from a capital and life cycle cost standpoint, and ties the plant staff to a regime similar to current labor intensive sludge handling operations. Based upon the lower capital and life cycle costs, and greater non-monetary benefits, AECOM recommends Paradise Irrigation District proceed with a recycled flush and back wash water treatment process similar to Alternative 3 of the Lee & Ro report. Process Water Recycling Project ES-3

10 Table ES-2 Summary of Advantages and Disadvantages Alternative 3 Mechanical Settling Advantages Similar to current operations. Less mechanical equipment. Less impact on plant site; less congested facilities layout. Less vulnerable to weather influences on residuals drying and disposal operations. Smallest footprint. Separate/new EQ tanks not required. Provides ability to handle the increased volume of clarifier flushes caused by periodic raw water quality events (algae blooms, fire damage in watershed) Allows for removal of existing EQ tank for maintenance without disrupting service by using one train temporarily for storage and pumping to remaining train in service. Wetlands Option Site 3 Disadvantages Reliant on existing washwater equalization tank for normal operations, which requires recoating and periodic maintenance. More mechanical equipment (flocculators, sludge collectors) than Sludge Ponds and Gravel Filter. Vulnerable to weather influences on residual drying operation (current condition). Less flexibility to accommodate future plant expansion. Process Water Recycling Project ES-4

11 Section 1 Introduction and Background 1.1 Background The operation of the Paradise Irrigation District (PID) Water Treatment Plant (WTP) results in a number of waste streams that require additional treatment. These flows include adsorption clarifier flush water, filter backwash water and filter-to-waste waters that are generated during the initial period when a filter is brought back on line after backwashing. Currently these flows are gathered in storage ponds, where the clarified water is decanted and discharged to Magalia Reservoir, see Figure 1-1. Because of this discharge, PID maintains a National Pollutant Discharge Elimination System (NPDES) Permit through the California Central Valley Water Quality Control Board (Regional Board). The current Permit expires in Raw Water Storage Tank WW EQ Tank Sludge Ponds Solids to Landfill Raw Water Pump Station Adsorption Clarifiers Filters Treated Water Tank Distribution Magalia Reservoir Figure 1-1. Existing Treatment Plant Flow Diagram As the permit renewal date approaches, PID is exploring methods of recycling the flushing and wash water streams and eliminating the need for the permit. Recycling this water has the added benefit of saving water, an opportunity especially important during drought years. Previous studies (Alternatives Evaluation Report, Lee & Ro, March 2014 and Constructed Wetlands Evaluation Report, Brown and Caldwell, March 2014) examined several options for treating these streams and returning them to the head of the plant. The recycled water must meet the requirements of the California Department of Public Health s Cryptosporidium Action Plan and Filter Backwash Recycling Rule. The plan requires that water recycled to the head of the plant has turbidity no greater than 2.0 NTU and is returned at a rate not to exceed ten percent of the flow through the main treatment plant. The Alternatives studied to date include: 1. Reconstruction of the existing North and South Sludge Ponds and constructing 2 million gallons of equalization basins. (Lee & Ro) 2. Flocculation and sedimentation of the washwater stream and 2 million gallons of equalization. (Lee & Ro) 3. Similar to Alternative 2, but with washwater clarification sized to equalize flush water from the clarifiers. (Lee & Ro) 4. No Project. Continue with existing washwater discharge to Magalia Reservoir. Process Water Recycling Project 1

12 Wetlands Option Site 3. Reconstruction of the existing North and South Sludge Ponds and constructing a gravel filter (constructed wetland ). (Brown and Caldwell) The Lee & Ro report recommended Alternative 3, while the Brown and Caldwell report outlined a concept for using the constructed wetlands concept (hereafter referred to as the Wetlands Option Site 3). The purpose of this study is to refine the capital costs for Alternative 3 and the Wetlands Option Site 3, and to estimate operations and maintenance costs over a twenty year life cycle. This study will enable PID to compare the total life cycle costs for the two Alternatives. Alternative 3, shown in Figure 1-2, recommended installing the following facilities sized for flow of 6.3 million gallons per day (mgd): Flocculation basins High rate sedimentation clarifiers with tube or plate settlers Mechanical dewatering of residual solids Washwater return pump station Yard piping to accommodate the new processes Floc Basins Clarifiers Raw Water Storage Tank WW EQ Tank Dewatering Solids to Landfill Raw Water Pump Station Adsorption Clarifiers Filters Treated Water Tank Distribution Magalia Reservoir Figure 1-2. Alternative 3 Plant Flow Diagram The Wetlands Option Site 3 includes the following: Reconstruction of the existing North and South Sludge Ponds Refurbishment of the existing wash water return pumps Installation of a constructed wetlands (gravel filter) Yard piping to accommodate the constructed wetlands Construction of a Sludge Drying Bed to increase drying capacity of the plant. Process Water Recycling Project 2

13 Solids to Landfill Sludge Drying Bed Sludge Ponds Raw Water Storage Tank WW EQ Tank Wetlands / Gravel Filter Raw Water Pump Station Adsorption Clarifiers Filters Treated Water Tank Distribution Magalia Reservoir Figure 1-3. Wetlands Option Site 3 Flow Diagram This report will discuss and document the improvements associated with Alternative 3 and bring the constructed wetlands approach to a comparable level of completeness. The report will present a comparative cost analysis of the capital and annual costs for each Alternative, using the same baseline unit costs (excavation, concrete, piping, etc.). 1.2 Cost Analysis Assumptions Assumptions associated with the cost analysis are shown in Table 1-1. The cost estimates presented in this Study is provided for budgeting and comparative purposes, and represents a planning-level effort, based on our best knowledge of current bid climate and installed costs for similar projects. Additional project details identified during planning, preliminary engineering, and design may increase or decrease the opinion of probable construction cost. Process Water Recycling Project 3

14 Table 1-1. Cost Analysis Assumptions Life Cycle Duration (2016 to 2035, years) 20 Discount Rate (annual percentage) 5% Inflation Rate (annual percentage) 3% Construction Contingency 30% General Conditions 10% Contractor Overhead and Profit 15% Escalation to Mid-Point of Construction (Two Years) 6.1% Staff Labor Rate (burdened per hour) (1) $42 Supervisory Labor Rate (burdened per hour) (1) $80 Projected population growth during life cycle (percent per year) (2) 1% Per capita water demand (gallons per day per user) (2) population (2) 27,365 Power Rates (per kwh) (1) Nov 1 to Apr 30 part peak/off peak (3) $0.162/ $0.133 May 1 to Oct 31 peak/part peak/off peak (4) $0.566/ $0.263/ $0.148 Annual Composite Power Rate (per kwh) $0.224 Annual Part Peak Power Rate (per kwh) $0.213 Chemical Consumption (gallons per year) (1) 330 Annual Chemical Cost (1) $8,000 Note: 1. from Jim Passanisi to Joe Huang, June 18, from George Barber to Joe Huang, Jun 20, Part peak is 8:30 am to 9:30 pm; Off peak is 9:30 pm to 8:30 am. 4. Peak is Noon to 6 pm; Part peak is 8:30 am to noon and 6 pm to 9:30 pm; Off peak is 9:30 pm to 8:30 am. Process Water Recycling Project 4

15 Section 2 Alternative 3 Mechanical Settling 2.1 Description The preliminary configuration of Alternative 3 treatment process would consist of coagulant addition and mixing, and flocculation followed by plate settlers. The residuals from the plate settlers will be dewatered by means of belt filter press or centrifuge. The washwater treatment process in this Alternative is sized for the instantaneous flow of flush water from the adsorption clarifiers (ACs). This flush water accounts for 50 to 78 percent of the total washwater generated depending on the time of year and the modes of operation. Currently raw water is used to flush the adsorption clarifiers. With Alternative 3 the adsorption clarifiers would be flushed with water treated by the washwater treatment process, instead of raw water. Thus, the treatment unit capacity is sized for the adsorption clarifier flush rate (6.3 mgd). With the majority of the recycled water being treated the need for additional equalization would be eliminated and there would be no need for two one-million gallon equalization tanks as required for Alternatives 1 and 2. The Lee & Ro report stated the California Department of Public Health (CDPH) has reviewed this concept and has indicated that they have no objection to flushing the clarifiers with treated flush water and washwater. This report assumes this statement is still correct. Flushing water from the adsorption clarifiers (ACs) is recycled back to the AC units during the flush cycle, basins were sized using less conservative values for flocculation time and for loading rates for the plate settlers when compared to basins sized for treating recycle flows to less than 2 NTU for recycling to the head of the plant. The loading rates assumed (0.5 gpm per square foot of plate settler area) are still within range of manufacturer recommended values for sizing plates and/or tube settler systems; however, longer flocculation times and lower loading rates are typically recommended under cold water conditions. During times when the adsorption clarifiers are not being flushed the new washwater clarifiers would treat filter backwash water and filter to waste water at a much lower rate of flow. This treated water would be returned to the main raw water pipeline. Figure 2-1 shows a process flow diagram for Alternative 3. Site plans showing the location of the Alternative 3 facilities and modifications required inside the filter gallery are shown on Figures 2-2 and 2-3. As part of this Alternative, a new 16-inch treated washwater pipeline would be routed from the new washwater clarification treatment area to the filter gallery. Once in the gallery this pipeline would be mounted adjacent to the 36-inch clarified water pipeline. From the new treated washwater pipeline automatic valves would control the flow of flush water to each individual adsorption clarifier. This Alternative would include the use of the existing equalization (EQ) tank, which is now 20 years old and in of need of rehabilitation. To be sure future maintenance could be provided at the EQ tank, piping from the return pumps at the washwater sedimentation tanks would be configured to allow the basins to be operated in series. Under this approach the first basin would provide equalization and the second basin clarification. Maintenance would have to be completed during periods of low flow (i.e., winter) when only one basin would be needed to meet clarification requirements. To accommodate the large differences in flow rate between the clarifier flush water and the treatment of filter wastewaters there would be two small pumps and two large pumps in the wet well at the end of the treatment units. Each of the larger pumps would be sized for the full clarifier recycle flow. If the operators wanted to increase the clarifier flushing rate for aggressive flushing at 11 mgd, they would be able to turn on Process Water Recycling Project 5

16 both of the larger pumps. The wet well would be sized to accommodate the fairly rapid changes in treated recycle flow rates. Table 2-1 presents a summary of the design criteria. Table 2-1. Alternative 3 Mechanical Settling Design Criteria Units AC Flush Equalized BW Future Winter Washwater Flow Washwater Flow mgd Recycle Flow gpm 4, Number of Process Trains in Service no. 2 1 Flow per Process Train gpm 2, Flocculation Basin Type -- Horizontal Plug Flow Horizontal Plug Flow Stages per Process Train no. 3 3 Flocculation Cell Dimensions (Each) Side Length ft Width ft Water Depth ft Volume per Train gal 38,800 38,800 Detention Time min High Rate Sedimentation Basin with Plate Settlers Number of Basins no 2 2 Basin Dimensions (Each) Length (3) ft Width ft Side Water Depth (4) ft Volume per Train gal 67,000 67,000 Detention Time min Plate Settlers Loading Rate gpm/sf Efficiency Projected Horizontal Pate Area per Basin sf 5,500 5,500 Plate Angle degrees Actual Plate Area sf 9,500 9,500 Plate Settler Width (5) ft Plate Settler Length (5) ft Number of Plates (5) no Notes: 1. Basin length based on quiescent zone of 20 feet, and a sludge hopper zone equal to 8 feet. 2. Side water depth assumes a chain-in-flight type collector is used 3. Basin length based on 2-inch plate spacing, two plate pack rows per basin, quiescent zone of 14 feet, and a sludge hopper zone equal to 8 feet. 4. Side water depth assumes a low profile type sludge collector is used for the plate settler basin alternative. Additional depth is required for chain-in-flight type collectors. 5. Plate settler dimensions and number of plates would be verified with manufacturer during design. Process Water Recycling Project 6

17 2.2 Dewatering The Lee & Ro report examined the quantity of residuals produced by the washwater treatment process and evaluated mechanical dewatering either by belt filter press or centrifuge. The decision on which method will be used is deferred until preliminary design of the project, and is not within the scope of this study. These two methods have similar capital costs, with the centrifuge option slightly higher. Thus, capital costs for the centrifuge option will be carried forward into the life cycle cost analysis. Tables 2-2 and 2-3 summarize the design criteria for each method. Table 2-2. Belt Filter Press Preliminary Design Criteria Criteria Current Buildout Residuals Production (1) (lb/day) Solids Flow at 0.5% concentration (gpd) 4,500 15,500 Number of 1.0 meter Belt Filter Presses 1 1 Belt Filter Press Hydraulic Loading Rate (gpm/meter of belt width) Belt Filter Press Solids Loading Rates (dry lb/hour/meter of belt width) Dry Polymer Feed Rate (pound/dry ton solid) Cake % Solids Hours of Operation per Day at Average Annual Residuals Production (2) (hr/day) Hours of Operation per Day at Maximum Month Residuals Production (2) (hr/day) Solids Storage Tank Size Diameter (ft) Height (ft) Volume (gal) 56,000 56,000 Additional Solids Storage in Clarification Basins (gal) 7,200 7,200 Note: 1. Current solids flow based on calculated average annual residuals production from 2011 through Future daily solids flow is based on maximum month, and is used for sizing dewatering facilities. 2. Hours of operation assumes press operation three days a week. Process Water Recycling Project 7

18 Table 2-3. Centrifuge Preliminary Design Criteria Criteria Current Buildout Residuals Production (1) (lb/day) Sludge Flow at 0.5% Solids (gpd) 4,500 15,500 Number of Centrifuges 1 1 Hydraulic Loading Rate (gpm) Cake % Solids Hours of Operation per Day at Average Annual Residuals Production (2) (hr/day) Hours of Operation per Day at Maximum Month Residuals Production (2) (hr/day) Clarified Solids Storage Tank Size Diameter (ft) Height (ft) Volume (gal) 56,000 56,000 Additional Sludge Storage in Clarification Basins (gal) 7,200 7,200 Note: 1. Current clarified solids flow based on calculated average annual residuals production from 2011 through Future daily clarified solids flow is based on maximum month, and is used for sizing dewatering facilities. 2. Hours of operation assume centrifuge operation three days a week. 2.3 Annual Costs Components of the annual costs are the following: Power to pump the treated washwater back to the head of the plant. Power for dewatering. Chemical usage for the washwater treatment. Chemical usage for the dewatering process. Maintenance of the equipment Power costs for pumping assume pumping an average of 8.5 percent of plant demand (based upon historical production of AC flushes and filter backwash water) at 50 feet of total dynamic head (30 feet of static head and 20 feet of dynamic head losses). As this pumping may occur at any time of day or year, the composite power rate was used. Power costs for dewatering assumes centrifuge use operating at 60 hp for 1.7 hours per day at part peak hours. As this usage can occur any time of year, the composite part peak power rate was used. Chemical usage for washwater treatment was assumed to be the triple that of current usage to account for a possible larger chemical dosage for the mechanical settling and additional polymer feed to dewatering. Present day usage was prorated to projected water demand. Process Water Recycling Project 8

19 Maintenance costs for the equipment were assumed to be proportional to the projected plant flow, with a current baseline of 100 hours each of regular staff labor and supervisory labor. Table 2-4 summarizes the annual costs and calculates a present worth of the annual costs based upon the 5 percent annual discount rate and 3 percent inflation. Table 2-4. Alternative 3 Annual Cost Summary Year Pumping Costs Dewatering Costs Chemical Costs Maintenance Costs Total Annual Cost Present Value 2016 $ 9,400 $ 5,300 $ 21,600 $ 11,900 $ 48,200 $ 46, $ 9,400 $ 5,300 $ 21,800 $ 12,000 $ 48,500 $ 45, $ 9,400 $ 5,300 $ 22,000 $ 12,100 $ 48,800 $ 45, $ 9,600 $ 5,500 $ 22,200 $ 12,200 $ 49,500 $ 45, $ 9,600 $ 5,500 $ 22,400 $ 12,300 $ 49,800 $ 44, $ 9,900 $ 5,500 $ 22,700 $ 12,500 $ 50,600 $ 44, $ 9,900 $ 5,500 $ 22,900 $ 12,600 $ 50,900 $ 43, $10,100 $ 5,800 $ 23,100 $ 12,700 $ 51,700 $ 43, $10,100 $ 5,800 $ 23,400 $ 12,800 $ 52,100 $ 43, $10,100 $ 5,800 $ 23,600 $ 13,000 $ 52,500 $ 42, $10,300 $ 6,000 $ 23,800 $ 13,100 $ 53,200 $ 42, $10,300 $ 6,000 $ 24,100 $ 13,200 $ 53,600 $ 41, $10,500 $ 6,000 $ 24,300 $ 13,400 $ 54,200 $ 41, $10,500 $ 6,000 $ 24,600 $ 13,500 $ 54,600 $ 40, $10,800 $ 6,200 $ 24,800 $ 13,600 $ 55,400 $ 40, $10,800 $ 6,200 $ 25,100 $ 13,800 $ 55,900 $ 40, $11,000 $ 6,200 $ 25,300 $ 13,900 $ 56,400 $ 39, $11,000 $ 6,400 $ 25,500 $ 14,000 $ 56,900 $ 39, $11,200 $ 6,400 $ 25,800 $ 14,200 $ 57,600 $ 39, $11,200 $ 6,400 $ 26,000 $ 14,300 $ 57,900 $ 38,700 Net Present Worth $850, Life Cycle Cost The annual and capital costs for Alternative 3 are presented in Table 2-5. A more detailed capital cost table is presented in Appendix A. As the centrifuge option is the more expensive of the two dewatering methods, these costs are included in Table 2-5. These costs are essentially identical to those presented in the Lee & Ro report. This report assumes the unit quantities presented in that report are correct. The unit costs have been modified to AECOM s understanding of current prices. The cost estimates are provided for budgeting and comparative purposes and represents a planning-level effort, based on our best knowledge of current bid climate and installed costs for similar projects. Additional project details identified during planning, preliminary engineering, and design may increase or decrease the opinion of probable construction cost. Process Water Recycling Project 9

20 Table 2-5. Alternative 3 Life Cycle Costs Cost Item Total Cost Alternative 3 Treatment Train $3,400,000 Residual Dewatering $1,700,000 Subtotal $5,100,000 Contingency (30 percent) $1,500,000 Subtotal $6,600,000 General Conditions (10 percent) $660,000 Subtotal $7,300,000 Overhead and Profit (15 percent) $1,100,000 Subtotal $8,400,000 Escalation to Mid-Point of Construction (6.1 percent) $510,000 Total Capital Cost $8,900,000 Annual Cost Present Worth $850,000 Note: Total Life Cycle Cost $9,800,000 These cost estimates are provided for budgeting and comparative purposes and represents a planning-level effort, based on our best knowledge of current bid climate and installed costs for similar projects. Additional project details identified during planning, preliminary engineering, and design may increase or decrease the opinion of probable construction cost. Process Water Recycling Project 10

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27 Section 3 Constructed Wetlands Option Site Description Brown and Caldwell (BC) issued a report documenting how constructed wetlands could be used to treat the backwash water and AC flush flow. The report proposed a one-acre area hybrid vertical/horizontal flow basin with pea gravel media over a rock underdrain located between the existing North and South Sludge Ponds. The basin would take decant water from the rehabilitated Sludge Ponds, removing the requisite amount of solids to reach the turbidity goal of less than 2 NTU. The BC report noted that gravel does not require vegetation to be planted; thus, the constructed wetlands is in effect a gravel media filter, operating similarly to a trickling filter in a wastewater treatment plant. Figure 3-1 shows a process flow diagram of the proposed treatment train. Because the gravel filter is in-line after the Sludge Ponds, this treatment scheme is similar to Alternative 1. The gravel filter replaces the 2 million gallon equalization basin from Alternative 1. In Alternative 1, as with this gravel filter option, most of the solids from the backwash water and the clarifier flush will settle in the Sludge Ponds. With most of the solids settling in the Sludge Ponds, the gravel filters will not have a treatment function, but serve as equalization. The filter proposed in BC s report actually has a larger footprint than the Alternative 1 basin because the gravel media will take up 60 percent of the volume of the basin, leaving 40 percent of void volume for water. Based upon the foundation of BC s report, this study will expand upon the concept and better define the required facilities for such a treatment approach. This report will also estimate efforts in operations and maintenance to establish a life cycle cost. 3.2 Permitting The CDPH has not permitted a gravel filter like that proposed for PID. However, in discussions with the Redding office, CDPH did not express concern with the means of treatment, so long as the process produces water in compliance with the Cryptosporidium Action Plan, that is, less than 2 NTU and can be modulated to be less than 10 percent of plant flow. 1 Nevertheless, PID will install the gravel filter at its own risk in case the scheme does not provide the performance needed to treat the water to less than 2 NTU. This risk is low as the current Sludge Ponds return decanted water meeting the turbidity criteria most of the time. 3.3 Scope of Facilities The BC report did not contain much detail regarding the Wetlands Option Site 3. This lack of detail caused an underestimation in the effort required to support the gravel filter. To flesh out the concept, this analysis examined the following details: Siting of the gravel filters within the water treatment plant site. 1 Telephone conference between Reese Crenshaw, CDPH, and Joseph Huang, AECOM, May 21, Process Water Recycling Project 17

28 Concepts to allow maintenance and cleaning of the gravel filters. Rehabilitation of the North and South Sludge Ponds to allow continued operation through the life cycle of the project. Sludge drying operations. The site between the North and South Sludge Ponds, where BC sited the gravel filter, does not have the room to accommodate a treatment basin with a surface area of one acre. The area between Pine Needle Drive and Skyway has space for a basin 270 feet long and 180 feet wide, divided into two cells (see Figure 3-2). Because of the area limitations of the plant site, the basin will require vertical walls to maximize the volume of the basin. The basins should have a water volume of two million gallons. After filling with pea gravel, the void volume remaining will be 40 percent of the total volume. Thus the required pea gravel depth is 15 feet. The gravel in each filter cell will be supported by a two foot deep bed of larger gravel. Within the gravel underdrain bed, perforated PVC pipe will be installed to collect the filtered water. The basin will be split to two parallel cells to enable cleaning and maintenance on one cell while keeping the other cell in service. New pipelines will be installed from the North and South Sludge Ponds to the Gravel Filter. Each pipeline will have fittings and valves to allow the operators to take a cell or the entire filter out of service. A 12-in diameter PVC return line will take the filtered water back to the head of the plant. This pipe size will allow flow by gravity, eliminating the need to pump back to the plant. A flow meter and flow control valve on the return pipeline will modulate the flow back to the plant and limit it to less than 10 percent of the treatment plant flow. The North and South Sludge Ponds walls will be lined with reinforced shotcrete with a reinforced concrete slab on the bottom, and split into two cells each. The Lee & Ro Report estimated receiving time of 97 days for each North Pond cell and 107 days for each South Pond cell. The accumulated sludge dries by evaporation and is then removed by the plant staff to ready the cell for the next receiving cycle. Plant staff has noted that even at current flow rates, dewatering of the sludge in the Sludge Ponds is insufficient for transport to the landfill. To this end, an additional sludge drying bed is considered as part of the Wetlands Option Site 3 alternative. The sludge drying basin is sized at 500,000 gallons, which is sufficient to receive sludge from both cells of either North or South Sludge Pond for a year. Thus, the plant can have one cell of a Sludge Pond in service, and one cell drying. At the end of the drying cycle, prior to receiving water again, the sludge will be removed to the proposed sludge drying basin where it will dry further. At the end of a year, most likely in October prior to the start of winter rains, the sludge drying basin will be cleaned and the dry sludge removed and hauled to a landfill. The sludge drying basin will have an inclined bottom to allow easy access for trucks and other cleaning vehicles. This basin can be located between the North and South Sludge Ponds as shown in Figure 3-2. The Lee & Ro report recommended improvements to the existing washwater pumping station to improve reliability. These improvements include increasing the size of the suction piping from the adsorption clarifiers and filters to the pump station, and installing a fourth pump. Other features of the gravel filter alternative include the following: A ramp into each cell will facilitate truck and loader access for removal and placement of media. Handrail will be provided around the perimeter of each basin. The existing fence along Pine Needle Drive will need to be relocated to encompass the basin. Table 3-1 presents a summary of the design criteria for the Wetlands Option Site 3 alternative. Process Water Recycling Project 18

29 Table 3-1. Wetlands Option Site 3 Design Criteria South Units North Ponds North and South Sludge Ponds Ponds Number of Cells ea 2 2 Surface Area (to normal high water level), each cell sf 10,700 11,800 Sludge Storage Volume, each cell gal 154, ,000 Side Water Depth ft Operating Water Depth (excludes 9-inches freeboard and 2.5 feet of sludge accumulation gal Operating Volume, each cell gall 261, ,000 Surface Loading Rate at 1,200 gpm (1) gpm/sf Detention Time at 1,200 gpm (2) min Horizontal Velocity at 1,200 gpm (3) ft/min Percent Solids in Sludge Ponds 3 3 Days of Storage at Average Annual Solids Production of 190lb/day days Days of Storage a Buildout Average Annual Solids Production of 400 lb/day days Gravel Filters Units Number of Cells no. 2 Length, each cell ft 270 Width, each cell ft 90 Side Water Depth ft 18 Depth of Pea Gravel ft 15 Pea Gravel Effective Size in 3/8 Depth of Gravel Underdrain ft 2 Underdrain Gravel Effective Size in 1 ½ Volume of Filter, each cell million gal 2.7 Void Volume of Pea Gravel percent 40 Void Volume of Filter, each cell million gal 1.1 Sludge Drying Bed Units Length ft 120 Width ft 135 Depth at Lowest Point ft 12 Bottom Slope percent 10 Effective Volume gal 500,000 Notes: 1. Surface loading rate based on the average surface area at mid depth of the normal operating range. Target surface loading rate to be less than 0.3 gpm/sf (MWH s Water Treatment Principles and Design, 3rd. Edition, 2012). 2. Recommended detention time for conventional sedimentation basins is 120 to 240 minutes (MWH s Water Treatment Principles and Design, 3rd. Edition, 2012). 3. Recommended range for horizontal velocity 0.5 to 3.0 feet/min (MWH s Water Treatment Principles and Design, 3rd. Edition, 2012). Process Water Recycling Project 19

30 3.4 Annual Costs Components of the annual costs are the following: Power to pump the AC flush water and filter backwash water back to North and South Sludge Ponds. Labor for cleaning the Sludge Ponds and Sludge Drying Bed. Chemical usage for the washwater treatment. Power costs for pumping assume pumping an average of 8.5 percent of plant demand (based upon historical production of AC flush and filter backwash water) at 120 feet of total dynamic head (100 feet of static head and 20 feet of dynamic head losses). As this pumping may occur at any time of day or year, the composite power rate was used. Labor costs for cleaning the Sludge Ponds assume 100 hours each of standard and supervisory labor prorated to percentage of current flow. 100 hours corresponds to the current time devoted by the staff for cleaning out the existing Sludge Ponds annually. Chemical usage for washwater treatment was assumed to be the same as the current usage. Present day usage was prorated to projected water demand. As there is no major mechanical equipment associated with this option, except for existing washwater pumps, maintenance costs for the equipment was considered negligible for this study. Costs for cleaning or replacing the media in the gravel filter are not included in this study. The frequency of this cleaning or replacement is unknown as this time. If, as anticipated, a large majority of solids settle out in the Sludge Ponds the gravel filter will need infrequent cleaning, if any at all, during the window of this analysis. Cleaning of the gravel would most likely consist of replacement of the media as providing the quantity of water for backwashing this large a basin is impractical. The cost of replacement media, based on the capital cost analysis, is $1,500,000. Table 3-2 summarizes the annual costs and calculates a present worth of the annual costs based upon the 5 percent annual discount rate and 3 percent inflation. 3.1 Life Cycle Cost The annual and capital costs for this Option are presented in Table 3-3. A more detailed capital cost table is presented in Appendix B. The capital costs include the gravel filter, rehabilitation of the existing North and South Sludge Ponds, a Sludge Drying Bed, and piping to support the process water flow. The cost for the filter and drying bed construction do not include shoring or other special excavation methods that site restrictions may require. The cost estimates are provided for budgeting and comparative purposes and represents a planning-level effort based on our best knowledge of current bid climate and installed costs for similar projects. Additional project details identified during planning, preliminary engineering, and design may increase or decrease the opinion of probable construction cost. Process Water Recycling Project 20

31 Table 3-2. Wetlands Option Site 3 Annual Cost Summary Year Pumping Costs Cleaning Costs Chemical Costs Total Annual Cost Present Value 2016 $22,400 $ 11,900 $ 7,200 $ 41,500 $ 39, $22,600 $ 12,000 $ 7,300 $ 41,900 $ 39, $22,800 $ 12,100 $ 7,300 $ 42,200 $ 39, $23,100 $ 12,200 $ 7,400 $ 42,700 $ 38, $23,300 $ 12,300 $ 7,500 $ 43,100 $ 38, $23,500 $ 12,500 $ 7,600 $ 43,600 $ 38, $23,700 $ 12,600 $ 7,600 $ 43,900 $ 37, $24,000 $ 12,700 $ 7,700 $ 44,400 $ 37, $24,200 $ 12,800 $ 7,800 $ 44,800 $ 37, $24,400 $ 13,000 $ 7,900 $ 45,300 $ 36, $24,600 $ 13,100 $ 7,900 $ 45,600 $ 36, $24,900 $ 13,200 $ 8,000 $ 46,100 $ 35, $25,100 $ 13,400 $ 8,100 $ 46,600 $ 35, $25,300 $ 13,500 $ 8,200 $ 47,000 $ 35, $25,800 $ 13,600 $ 8,300 $ 47,700 $ 35, $26,000 $ 13,800 $ 8,400 $ 48,200 $ 34, $26,200 $ 13,900 $ 8,400 $ 48,500 $ 34, $26,400 $ 14,000 $ 8,500 $ 48,900 $ 33, $26,700 $ 14,200 $ 8,600 $ 49,500 $ 33, $26,900 $ 14,300 $ 8,700 $ 49,900 $ 33,300 Net Present Worth $730,000 Table 3-3. Wetlands Option Site 3 Life Cycle Cost Cost Item Total Cost Gravel Filter Train $8,900,000 Contingency (30 percent) $2,700,000 Subtotal $11,700,000 General Conditions (10 percent) $1,200,000 Subtotal $12,800,000 Overhead and Profit (15 percent) $1,900,000 Subtotal $14,700,000 Escalation to Mid-Point of Construction (6.1 percent) $900,000 Total Capital Cost $15,600,000 Annual Cost Present Worth $730,000 Note: Total Life Cycle Cost $16,400,000 These cost estimates are provided for budgeting and comparative purposes and represents a planning-level effort based on our best knowledge of current bid climate and installed costs for similar projects. Additional project details identified during planning, preliminary engineering, and design may increase or decrease the opinion of probable construction cost. Process Water Recycling Project 21

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37 Section 4 Summary and Conclusions 4.1 Comparison of Life Cycle Costs Table 4-1 compares the life cycle costs between the mechanical settling and gravel filter option. Because of the large capital costs of the Wetlands Option Site 3, its life cycle cost is over 60% greater than that of Alternative 3. Table 4-1. Life Cycle Cost Comparison Cost Item Alternative 3 Mechanical Settling Wetlands Option Site 3 Capital Cost $5,100,000 $8,900,000 Contingency (30 percent) $1,500,000 $2,700,000 Subtotal $6,600,000 $11,600,000 General Conditions (10 percent) $660,000 $1,200,000 Subtotal $7,300,000 $12,800,000 Overhead and Profit (15 percent) $1,100,000 $1,900,000 Subtotal $8,400,000 $14,700,000 Escalation to Mid-Point of Construction (6.1 percent) $510,000 $900,000 Total Capital Cost $8,900,000 $15,600,000 Annual Cost Present Worth $850,000 $730,000 Total Life Cycle Cost $9,800,000 $16,400,000 Note: These cost estimates are provided for budgeting and comparative purposes and represents a planning-level effort, based on our best knowledge of current bid climate and installed costs for similar projects. Additional project details identified during planning, preliminary engineering, and design may increase or decrease the opinion of probable construction cost. 4.2 Non-Monetary Considerations Although the life cycle cost analysis heavily favors Alternative 3, non-monetary factors should also be considered when selecting the preferred Alternative. A summary of non-monetary benefits for both Alternatives is presented in Table 4-2. Process Water Recycling Project 27

38 Table 4-2 Summary of Advantages and Disadvantages Alternative 3 Mechanical Settling Advantages Similar to current operations. Less mechanical equipment. Less impact on plant site; less congested facilities layout. Less vulnerable to weather influences on residuals drying and disposal operations. Smallest footprint. Separate/new EQ tanks not required. Provides ability to handle the increased volume of clarifier flushes caused by periodic raw water quality events (algae blooms, fire damage in watershed) Allows for removal of existing EQ tank for maintenance without disrupting service by using one train temporarily for storage and pumping to remaining train in service. Wetlands Option Site 3 Disadvantages Reliant on existing washwater equalization tank for normal operations, which requires recoating and periodic maintenance. More mechanical equipment (flocculators, sludge collectors) than Sludge Ponds and Gravel Filter. Vulnerable to weather influences on residual drying operation (current condition). Less flexibility to accommodate future plant expansion. Based on the comparison of the non-monetary factors considered above, including impact to space, operations, and flexibility, Alternative 3 is preferred. 4.3 Recommended Project The constructed Wetlands Options Site 3 is not financially viable from a capital and life cycle cost standpoint, and ties the plant staff to a regime similar to current labor intensive sludge handling operations. Based upon the lower capital and life cycle costs, and greater non-monetary benefits, AECOM recommends Paradise Irrigation District proceed with a recycled flush and back wash water treatment process similar to Alternative 3 of the Lee & Ro report. Process Water Recycling Project 28

39 Appendix A Alternative 3 Mechanical Settling Detailed Opinion of Probable Construction Cost

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41 Paradise Irrigation District PROJECT TITLE & LOCATION: PROJECT # PREPARED BY: J. Huang SHEET: 1 of 1 CONCEPTUAL DESIGN Paradise Irrigation District OPINION OF PROBABLE Process Water Recycling Project TASK: 20 CHECKED BY: D. Schottlander DATE: 6/27/2014 CONSTRUCTION COST ALTERNATIVE 3 - WASHWATER CLARIFICATION WITH PLATE SETTLERS SIZED FOR 6.3 MGD ITEM DESCRIPTION: QUANTITY MATERIAL COST LABOR COST MATERIAL AND LABOR (INCLUDE SPECIFICATION REFERENCE IF POSSIBLE) NUMBER UNIT UNIT COST TOTAL UNIT COST TOTAL UNIT COST TOTAL Division 2 Grading and Site Preparation 750 SY $ 2 $ 1,500 Excavation 1,440 CY $ 15 $ 21,600 Backfill 481 CY $ 24 $ 11,500 Aggregate Base Course 280 CY $ 50 $ 14,000 Off-Haul 1,150 CY $ 20 $ 22,400 Division 3 Slab on Grade (SOG) 371 CY $ 500 $ 185,500 Clarified Washwater Pump Station & Weir Walls 127 CY $ 870 $ 110,500 Polymer and Electrical Room Walls 48 CY $ 870 $ 41,800 Floc Basins and Sludge Pump Station Walls 139 CY $ 870 $ 120,900 Sedimentation Basin Walls 140 CY $ 870 $ 121,800 Elevated Deck Pump & Polymer Rooms & CWW Pmp Sta 67 CY $ 1,200 $ 80,400 Concrete Walkway 52 CY $ 1,200 $ 62,400 Division 5 Handrail 635 LF $ 35 $ 22,225 $ 15 $ 9,525 $ 50 $ 31,800 Misc Hose Racks, Supports, Access Hatches 1 LS $ 10,000 $ 10,000 Aluminum Stairs 2 LS $ 5,000 $ 10,000 Division 6 Flocculation basin redwood baffles 1,008 SF $ 25 $ 25,200 Division 7 Thermal and Moisture Protection Roofing 1 LS $ 6,200 $ 6,200 Division 8 Doors and Windows Overhead Coiling Door 1 EA $ 10,000 $ 10,000 Doors 4 EA $ 2,500 $ 10,000 Division 9 Protective Coatings 1 LS $ 33,800 $ 33,800 Division 10 Emergency Shower & Eyewash 1 EA $ 2,500 $ 2,500 Division 11 Polymer Blending Unit 2 EA $ 20,000 $ 40,000 Sump Pump 1 EA $ 2,000 $ 2,000 Washwater Paddle Flocculators 1 LS $ 176,300 $ 176,300 $ 52,890 $ 229,190 $ 229,200 Sed Basin Sludge Collectors & Cross Collectors 1 LS $ 119,863 $ 119,863 $ 35,959 $ 35,959 $ 155,821 $ 155,800 Clarified Washwater Return Pumps 1 LS $ 200,000 $ 200,000 Washwater Sludge Pumps 1 LS $ 55,000 $ 55,000 Static Mixer 1 LS $ 6,000 $ 6,000 Plate Settlers & Effluent Troughs with Support System 1 LS $ 202,100 $ 202,100 $ 60,630 $ 60,630 $ 262,730 $ 262,700 Division 15 4" SL from Sludge Room to Dewatering Process 450 LF $ 130 $ 58,500 6" D from Dewatering Process to 24" RW 50 LF $ 150 $ 7,500 Tie-in with 36" Raw Water Pipeline 1 LS $ 2,000 $ 2,000 $ 3,000 $ 3,000 $ 5,000 $ 5,000 Polymer Piping 1 LS $ 4,000 $ 4,000 WW Sludge Misc Piping and Valves 1 LS $ 19,000 $ 19,000 Misc Water Piping for PW & DW 1 LS $ 10,000 $ 10,000 HVAC 1 LS $ 30,000 $ 30, ACW from 24" ACW connection to Clarifiers 340 LF $ 250 $ 85,000 8" CWW from WW PS to RW Pipe 250 LF $ 170 $ 42,500 10" WW Recycle from Floc/Se 1 to Floc Sed LF $ 200 $ 45,000 16" CWW AC Flush Water Supply 450 LF $ 250 $ 112,500 24" BRW - Isolation BFV 1 EA $ 8,500 $ 8,500 16" BRW - Control BFV 1 EA $ 13,750 $ 13,800 16" BRW - Isolation BFV 5 EA $ 5,500 $ 27,500 16" AC Inlet Piping Valves (Pneumatically Actuated) 3 EA $ 13,750 $ 41,300 16" AC Inlet Piping Modifications and New Flushing Header 1 LS $ 150,000 $ 150,000 16" CWW-Flush / WW-Recycle 16" Isolation Value 1 EA $ 5,500 $ 5,500 10"CWW-Flush / WW-Recycle 16" Isolation Value 1 EA $ 1,000 $ 1,000

42 Paradise Irrigation District PROJECT TITLE & LOCATION: PROJECT # PREPARED BY: J. Huang SHEET: 1 of 1 CONCEPTUAL DESIGN Paradise Irrigation District OPINION OF PROBABLE Process Water Recycling Project TASK: 20 CHECKED BY: D. Schottlander DATE: 6/27/2014 CONSTRUCTION COST ALTERNATIVE 3 - WASHWATER CLARIFICATION WITH PLATE SETTLERS SIZED FOR 6.3 MGD ITEM DESCRIPTION: QUANTITY MATERIAL COST LABOR COST MATERIAL AND LABOR (INCLUDE SPECIFICATION REFERENCE IF POSSIBLE) NUMBER UNIT UNIT COST TOTAL UNIT COST TOTAL UNIT COST TOTAL CWW Misc Piping and Valves at Pumps 1 LS $ 27,000 $ 27,000 Floc/Sed Basin Interconnection Wetwell Gate 1 LS $ 7,500 $ 7,500 Equlization Tank 24" High Capacity Outlet Modifications 1 LS $ 12,000 Division 16 & 17 Electrical and Instrumentation (30 % of Div 2-15) 1 LS $ 779,280 $ 779,300 SUBTOTAL $ 3,377,000 CONTINGENCY 30% $ 1,013,000 SUBTOTAL $ 4,390,000 GENERAL CONDITIONS 10% $ 439,000 SUBTOTAL $ 4,829,000 OVERHEAD & PROFIT 15% $ 724,000 SUBTOTAL $ 5,553,000 ESCALATION TO MID-POINT OF CONSTRUCTION (2 YRS) 6% $ 339,000 TOTAL ESTIMATED CONSTRUCTION COST $ 5,892,000 TYPE OF ESTIMATE BASE TIME OF ESTIMATE BASIS OF ESTIMATE (FACTORS TO CONSIDER) ( X ) CONCEPT ( X ) CURRENT COST AT ENRCCI OF 9668 (Dec 2013) ( X ) LOCATION FACTOR ( ) LABOR AVAILABILITY ( ) 50% SUBMITTAL ( ) MID-CONSTRUCTION, (MONTH/YEAR / ) ( ) COMPLEXITY FACTOR ( ) SCHEDULE (OVERTIME) ( ) FINAL AT ENRCCI OF ( X ) PROJECT SIZE FACTOR ( ) MARKET (ECONOMY)

43 Paradise Irrigation District PROJECT TITLE & LOCATION: PROJECT # PREPARED BY: J. Huang SHEET: 1 of 1 CONCEPTUAL DESIGN Paradise Irrigation District OPINION OF PROBABLE Process Water Recycling Project TASK: 20 CHECKED BY: D. Schottlander DATE: 6/27/2014 CONSTRUCTION COST DEWATERING - CENTRIFUGE BUILDING & DEMOLITION OF EXISTING FILTER STRUCTURE ITEM DESCRIPTION: QUANTITY MATERIAL COST LABOR COST MATERIAL AND LABOR (INCLUDE SPECIFICATION REFERENCE IF POSSIBLE) NUMBER UNIT UNIT COST TOTAL UNIT COST TOTAL UNIT COST TOTAL Division 2 Demolition of exist. structure (walls & filters only) 300 CY $ 250 $ 75,000 Demolition of slab 150 CY $ 250 $ 37,500 Demolition of misc. other components 1 LS $ 50,000 $ 50,000 Excavation 200 CY $ 15 $ 3,000 $ 8 $ 1,600 $ 23 $ 4,600 Backfill 300 CY $ 32 $ 9,600 Division 3 Truck Off-Loading SOG 25 CY $ 560 $ 14,000 Dewatering Building SOG 35 CY $ 560 $ 19,600 Sludge Storage Tank SOG 24 CY $ 560 $ 13,440 Aggregate Base for Sludge Storage Tank 24 CY $ 60 $ 1,440 Division 5 Miscellaneous Metals and Supports 1 LS $ 15,000 $ 12,500 Division 8 Doors and Windows Doors and Windows 1 LS $ 15,000 $ 15,000 Division 9 Miscellaneous Coatings 1 LS $ 5,000 $ 5,000 Division 11 Truck Off-Loading Conveyor 1 EA $ 30,000 $ 30,000 $ 9,000 $ 9,000 $ 39,000 $ 39,000 Skid Mounted Centrifuge 1 EA $ 483,750 $ 483,750 $ 96,750 $ 96,750 $ 580,500 $ 580,500 Centrate Pump Station 1 LS $ 22,500 Division 13 Sludge Storage Tank 1 EA $ 60,000 $ 60,000 $ 18,000 $ 18,000 $ 78,000 $ 78,000 Division 15 Dewatering Building 900 SF $ 200 $ 180,000 Truck Off-Loading Canopy 675 SF $ 100 $ 67,500 Sludge Piping at Dewatering Building 1 LS $ 50,000 $ 50,000 Misc Piping 1 LS $ 50,000 $ 50,000 Polymer and Water Piping 1 LS $ 20,000 $ 20,000 HVAC 1 LS $ 25,000 $ 25,000 Division 16 & 17 Electrical and Instrumentation Electrical & Instrumentation (30 % of Division 3-15) 1 LS $358,044 $ 358,044 Didn't include Div 2 since that is associated with filter demo SUBTOTAL $ 1,728,000 CONTINGENCY 30% $ 518,000 SUBTOTAL $ 2,246,000 GENERAL CONDITIONS 10% $ 225,000 SUBTOTAL $ 2,471,000 OVERHEAD & PROFIT 15% $ 371,000 SUBTOTAL $ 2,842,000 ESCALATION TO MID-POINT OF CONSTRUCTION 6% $ 173,000 TOTAL ESTIMATED CONSTRUCTION COST $ 3,015,000 TYPE OF ESTIMATE BASE TIME OF ESTIMATE BASIS OF ESTIMATE (FACTORS TO CONSIDER) ( X ) CONCEPT ( X ) CURRENT COST AT ENRCCI OF 9668 (Dec 2013) ( X ) LOCATION FACTOR ( ) LABOR AVAILABILITY ( ) 50% SUBMITTAL ( ) MID-CONSTRUCTION, (MONTH/YEAR / ) ( ) COMPLEXITY FACTOR ( ) SCHEDULE (OVERTIME) ( ) FINAL AT ENRCCI OF ( X ) PROJECT SIZE FACTOR ( ) MARKET (ECONOMY)