How Do The Availability of Outlets and End Use of Solids Affect Solids Management Alternatives? A Case Study for Millville Facility in New Jersey

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1 How Do The Availability of Outlets and End Use of Solids Affect Solids Management Alternatives? A Case Study for Millville Facility in New Jersey Tepe-Sencayir, Nalan 1 ; Abu-Orf, Mohammad 1 ; Burt, Floyd 2 1 AECOM 1700 Market Street, Suite 1700 Philadelphia, PA City of Millville, New Jersey ABSTRACT Thickened mixed primary and waste activated sludge of approximately 2% solids concentration from the Millville Wastewater Treatment Facility in Southern New Jersey are dewatered using two (2) belt filter presses (BFP) to approximately 18-20% total solids, before hauling to Atlantic County Utilities (ACUA) for processing via incineration. Plant process evaluation showed that the dewatering facility is not capable of handling current and future solids loads. Rather than just replacing the existing BFP with newer, larger units, The City of Millville decided on conducting a solids study aiming at evaluating plant solids processing and studying available end use options and outlets for the produced solids. Initially, the available and viable solids outlets within the state of New Jersey were evaluated along with the established residuals characteristics for these outlets. Once these outlets were identified, the required in-plant processing changes that should be practiced to produce solids characteristics matching the available outlets were investigated. These outlets were evaluated based on cost and reliability processing the City s generated solids. Eight in-plant solids processing alternatives, producing Class A, Class B or raw solids were identified based on the available outlets. Alternative configurations were then analyzed based on capital cost, operation and maintenance costs along with a qualitative comparison. This paper summarizes outcomes of the research on existing solids practices in NJ, particularly Southern New Jersey, technologies and alternatives for processing solids and recommended alternative for processing and accepting solids. Based on the available outlets and economic evaluation of alternatives, processing the solids to either Class A or B is not necessary. However, the plant needs to produce higher cake solids than currently practiced. KEYWORDS Solids management, dewatering, stabilization, end use, incineration INTRODUCTION Currently, the waste activated sludge (WAS) from the aeration basins is thickened to approximately 5% total solids concentration with two (2) gravity belt thickeners (GBT). The thickened WAS is then mixed with the primary solids in an aerated holding tank. The mixed solids are then dewatered using two (2) belt filter presses (BFP) with the goal of obtaining

2 approximately 20% cake solids before hauled and further processed by incineration at the Atlantic County Utilities (ACUA). A plant upgrade design (Phase I) is in progress to enable the plant to treat current plant flows (2.5 MGD) more reliably. A future upgrade will eventually be performed (Phase II) to accommodate projected future flow of 5 MGD. Table 1 summarizes solids production at the existing and future flow rates. Table 1 - Existing and Future Solids Production Solids Production (dry tons/day) Annual Average Day Existing (2.5 MGD) Max 30-day average Annual Average Day Future (5 MGD) Max 30- day average The City of Millville was interested in conducting a market study and technology evaluation for dewatering and stabilizing their current and future solids. AECOM Water was authorized to conduct a sludge study aimed at evaluating plant solids processing and studying available solids outlets. Initially, a review of residuals regulations of New Jersey State was conducted. A market study of the available solids outlets within the state and neighboring states was conducted since end-use practices and available outlets drive in-plant solids processing. The cost effectiveness of the required solids processes changes and the long term sustainability of the solids outlet were used as the main criteria for recommending changes to the plant s solids processing. Alternatives and technologies were developed and screened to match the available outlets. STATE REQUIREMENTS FOR RESIDUALS BENEFICIAL USE/PROCESSING The state regulations for residuals management are found at New Jersey s Standards for the Use or Disposal of Residuals (N.J.A.C. 7:14A-20) which are based on 40 CFR Part 503 regulations. The regulations cover requirements including, but not limited, land application, surface disposal, residual transfer stations, and reed beds. Landfilling or Surface Disposition New Jersey is a densely populated State with minimal land area available for commitment to waste disposition. Therefore, in general residuals landfilling in the state of New Jersey is prohibited; however, surface disposition of biosolids in landfills is available in nearby out-ofstate landfills. For instance, if the residuals are stabilized or digested, they will be acceptable at Waste Management landfills in Pennsylvania within 80 miles to the Millville Plant. The closest landfill operated by Waste Management that would accept the existing non-stabilized solids is located in Ohio. Even though, landfill of biosolids is allowed in the state of Delaware, the

3 Delaware Solid Waste (DSWA) would not accept any out-of-state wastes, and biosolids are considered a waste. Land Application of Class A or Class B Biosolids New Jersey Department of Environmental Protection (NJDEP) regulations provide six different land application programs which are grouped in two scenarios based on the level of quality, pathogen reduction and vector attraction reduction (VAR) requirements achieved (NJDEP, 1998). These programs are summarized in the Table 2. Once prepared based on one of the programs, residuals must be land applied in conformance with two scenarios. Table 2 - Summary of NJDEP Land Application Programs Scenario 1 (EQ Quality) Scenario 2 (Non-EQ Quality) Land Application Programs LLAMA* Required Pathogen Reduction Requirements VAR Requirements** Site Restrictions Program 1 No Class A Option 1-8 No Program 2 Yes Class A Option 9 or 10 No Program 3 Yes Class B Any Yes Program 4 Yes Class A Option 1-8 No Program 5 Yes Class A Option 9 or 10 No Program 6 Yes Class B Any Yes * Letter of Land Application Management Approval ** Options per Part 503 Regulations Scenario 1: Exceptional Quality (EQ) residuals available as marketable products. EQ residuals meet pollutant, pathogen reduction and vector attraction reduction criteria (Program 1) such that the risks of managing them are matching with those of managing other types of fertilizers or soil amendments. Under this scenario, approvals for the residual land application site are not required and additional public notice is not required other than the public review and comment procedures for the NJ Pollutant Discharge Elimination System (NJPDES) permit of the EQ residuals producer. Scenario 2: Non-EQ residuals applied to land that has been evaluated by the Department and approved by Letter of Land Application Management Approval (LLAMA). The use of non-eq residuals (Programs 2 through 6) at agronomic rates and under specific restrictions provides the benefits but does not exceed the risks of EQ residuals or other commercial agricultural soil additives. The LLAMA will detail site specific restrictions applicable to non-eq residual and to the site where application will occur. Considering the high population density and public resistance, the land application of biosolids in New Jersey has been challenging. Therefore, NJDEP implemented more stringent regulatory requirements to address residual products that may, or have been found to, create a nuisance. The

4 Department requires site specific approvals or other product specific restrictions in order to control odors. As a result, it is required to present information that new residual products will meet marketable residual product standards and that the product will not exhibit nuisance characteristics (NJDEP, 2005). Biosolids generators that would land apply in NJ are mostly EQ biosolids producers. The use of Non-EQ biosolids is estimated to be less than 3% of overall residuals production and is regulated stringently for land application. In-state beneficial use of sewage residuals has been falling after year 2000 due to increased program enforcement by DEP and due to the limited amount of available land on which biosolids can be applied. Several factors limit the potential for expanding the land application of biosolids in New Jersey, which include public opposition due to odors, perceived public health concerns, and nuisance. Other factors include perceived liability concerns of landowners, and the type of crop grown. Other Beneficial Use Beneficial uses of biosolids are not limited to the production of fertilizers or soil amendments. In recent years the most common method was the use of biosolids as landfill cover or top soils, particularly in Northern New Jersey. NJDEP encourages the beneficial use of marketable residual products or stabilized residuals as a supplement to the final soil overlying the final landfill cap or daily cover. The use of stabilized residuals or other marketable residual products can improve the productivity of the final soil cover of certain completed landfills, and thus aid in re-vegetation and ultimate reclamation efforts without creating environmental harm. Any alternate material other than clean soil proposed for use as daily, intermediate or final cover material at a sanitary landfill is subject to the approval of the Solid Waste Division of NJDEP. If possessing soil-like properties, additional laboratory testing for the alternate material may be required depending on the material and its intended use. These tests include, but not limited to, solids content, percent volatile solids, grain size analyses, and moisture content. For material intended for use in the topsoil layer in a final cover, tests to provide nutrient content are also required. A demonstration of the biosolids use as cover may also be requested as part of the approval process. Land application of Class A or Class B biosolids is decreasing since 2003, but the use as landfill cover in Northern New Jersey is significantly increasing. Unfortunately, there is no landfill in the Southern New Jersey that has an approved protocol for the use of biosolids, mostly as daily cover or top soil. This is due to lack of practice or knowledge from landfill owners resulting in refusal to accept biosolids as a daily cover. Southern counties should investigate this alternative and learn from the experience of northern counties. This practice can be beneficial to both sewage authorities and landfill owners. All residuals incinerators require permits from Air Quality Permits from NJDEP s Air Pollution Control Program to control air pollution emissions. Treatment Works Approval from the Division of Water quality is required all residuals handling and processing equipment prior to the incineration. In addition, for new and expanded residuals incinerators, an environmental

5 assessment report is required which is reviewed by both divisions. Unlike land application, incinerator owners may accept customers without the Department s case-by-case determination as long as emission permit is not violated. of residuals is an integral and necessary part of the State's residuals management strategy. Incinerators provide significant volume and mass reduction, operate in all seasons, except when scheduled and un-scheduled maintenance are needed, and without nuisance, and do not require significant land commitment for processing. The end product, ash, can be landfilled, utilized as daily cover or beneficially used elsewhere. BIOSOLIDS MANAGEMENT TRENDS in NEW JERSEY A number of facilities were contacted and available data on the NJDEP website was reviewed to obtain information on the current biosolids management practices in New Jersey. According to the most recent data published by NJDEP (2006) as shown in Table 3, almost 23% of residuals was incinerated and almost same amount of residuals was processed out-of-state. Only 8.59% and 2.27% was beneficially used as Class A and Class B, respectively. Less than 1% was processed through Reed Beds. The remaining 44% percent of residuals was beneficially used in a non-traditional manner as an alternate landfill cover component. There are a number of landfills with approved protocol for the use of biosolids in Northern New Jersey; however, landfills in the south have not realized this route of beneficial use yet. Table 3 - Residuals Production in NJ and Processing Methods in 2006 Dry metric tons Percentage 63, % Class A Beneficial use 23, % Class B Beneficial use 6, % In-state Ben Use 121, % Reed Beds and other % In State Use Subtotal 215, % Out of State Ben. Use 49, % Out of State Use 13, % Out of State Use Subtotal 62, % TOTAL 278, % Figure 1 presents in-state biosolids beneficial use trend from 2001 through Class A and Class B beneficial use indicate use as fertilizer and soil amendment. The part of biosolids categorized as other is mainly using biosolids as landfill cover component.

6 Figure 1 Distribution of Beneficial Use of Biosolids in New Jersey 60% Percentage of Overall Sludge Production 50% 40% 30% 20% 10% 8.5% 3.4% 25.6% 8.6% 3.4% 17.0% 7.7% 2.5% 13.7% 19.4% 2.5% 11.2% 38.1% 2.2% 9.2% 43.6% 2.3% 8.6% 0% Years Class A Class B Other (Mostly as landfill cover) State Current Biosolids Practices Figure 2 presents the residuals management and end use modes for different counties in NJ and some of the smaller municipalities that manage biosolids on their own. The City of Millville is located in Cumberland County where centralized residuals processing is not available. This presents a challenge to small cities such as Millville when managing and processing residuals, requiring them to rely on out-of-county disposition methods. The county owned treatment plant is currently practicing land application of Class B liquid biosolids by a method called subsurface injection. The largest residuals producer in the County, Landis Sewage is also producing Class B biosolids and land applies the biosolids on city owned farmland, woodland and utility easement. Conversely, Burlington County took full responsibility of biosolids management for municipalities located in the county. A composting facility producing Class A compost was constructed to process dewatered cake solids and other organic material. The facility always reserves capacity for local municipalities and the remaining capacity is contracted by the contract operator (currently WeCare Organics, Inc.). The municipalities that don t practice dewatering generally transfer their solids to the facility of Mount Holly Municipal Utility to be dewatered and subsequently hauled to the composting facility. Only Pemberton Township in Burlington County is land applying the digested biosolids on the township owned land.

7 Figure 2 - Residuals Management and End Use in the State of New Jersey by Counties Sussex Co. UA Composting Wayne Twp. Northwest Bergen Co. UA - Lincoln Park - Fairfield SA and Par-Troy - Musconetcong SA- Composting Passaic Valley SC Beneficial Use (Land application, landfill cover) Somerset Raritan Valley SA - Joint Meeting of Union and Essex Counties - Pelletization Stony Brook Reg. SA Burlington County - Composting Pemberton Twp Land application Middlesex Co UA Beneficial Use (Landfill cover) Bayshore Reg. SA Camden Co. MUA No county owned facility (Composting offline) Ocean Co. UA Pelletization Gloucester Co. UA Atlantic Co UA - Buena Borough - Composting Cumberland Co. UA and Landis SA Anaerobic Digestion Liquid Sludge Land Application Cape May Co. MUA -Composting Lower Twp - High ph/high Temp

8 Cape May County Municipal Utilities (CMCMUA) also operates a composting facility. The product, CapeOrganic, contains fully processed biosolids which has been composted and blended with hogged wood chips. The main use of the compost is to enrich topsoil, either through in situ incorporation, or in a stand-alone blending operation. Other uses include topdressing of athletic fields and other turf areas, landscaping uses, uses by nurseries, and for side slope stabilization and erosion control at landfills and construction sites. Another successful marketable biosolids fertilizer producer in Southern New Jersey is the Ocean County Utilities (OCUA). Fertilizer Manufacturing Division (FMD) of OCUA receives thickened digested biosolids from three county owned plants. The facility has a pelletilization system where the biosolids are thermally dried, producing pellets that are used as organic fertilizer which exceeds EPA s Exceptional Quality Standards. The award winning product, called OceanGrow, is sold to golf courses, landscape contractors and garden centers. It is important to note that successful marketing efforts with dedicated personnel are the main reasons behind the county s success with their beneficial use program. As mentioned earlier, Atlantic County operates an incinerator; however, Buena Borough in the County has a composting facility which produces about 4,500 cubic yards (CY) annually. The facility is relatively small-sized with a design flow of 0.4 mgd. First the compost was intended to being sold, but the borough had difficulty selling the product. Now, the compost is given away to public. The largest biosolids producer, Middlesex County, currently produces lime stabilized Class A biosolids that is used at the Middlesex landfill as a daily cover and a top soil for closures. In 1990 s, they were working with agricultural contractors for land application at farms. However they abandoned this method due to public complaints and requirements of regular inspections. The Passaic Valley Sewerage Commissioners (PVSC) operates a large treatment plant in Newark, NJ that treats the domestic and industrial wastewaters of northeastern New Jersey. This area consists of 47 municipalities in portions of Passaic, Bergen, Essex, and Hudson counties. The facility utilizes pure oxygen-activated sludge process with Zimpro wet air oxidation for residuals treatment. Class A dewatered product is taken by a contractor for use as landfill cover and land application in other states. Joint Meeting of Essex and Union Counties (JMEUC) facility is producing anaerobically digested lime stabilized biosolids. The anaerobic digestion process is not operated in a manner to achieve EPA s pathogen reduction or vector attraction reduction requirements. Those requirements are achieved via lime-stabilization. Anaerobically digested biosolids is dewatered by high solids centrifuges. Dewatered cake is conveyed to the onsite lime stabilization process prior to the truck loading area. The stabilized biosolids are transported to eastern Virginia by rail for land application. Synagro, JMEUC Contractor, is responsible for coordinating all shipments of biosolids from the plant site to the permitted agricultural sites in Virginia. As seen in Figure 2, there are also a number of county owned or regional incinerators that are utilized for sludge management. Incinerators produce an ash product that also needs to be managed. In many cases, the ash is landfilled or beneficially used as landfill cover or any alternative use approved by NJDEP.

9 AVAILABLE SOLIDS OUTLETS FOR THE CITY OF MILLVILLE As discussed earlier, the City of Millville is producing non-stabilized dewatered cake. Meeting the requirements established by facilities accepting dewatered cake is essential, and these criteria are discussed for the available outlets in this section. Since the metal concentrations in the residuals are lower than the EPA s pollutant concentrations, it is acceptable by most of facilities accepting stabilized and un-stabilized solids based on pollutant criteria. A summary of end use methods and required residuals characteristics is presented in Table 4. Depending on the end use, required solids characteristics should be met and solids processing equipment should be upgraded as necessary. Table 4 - End Use Evaluation End Use Method Landfilling Applicability Required solids Characteristics Comments In New Jersey N/A - Landfilling is prohibited in NJ In Pennsylvania Applicable Class A or Class B, more than 20% solids Land Application Only stabilized or digested dewatered biosolids is accepted Class A Cake N/A Class A Outlets are not available Class A Pellets Applicable Class A Requires product marketing Class A Compost Applicable Class A Requires product marketing Class B Biosolids N/A Class B Very limited permitting Other Beneficial Use Landfill Cover Applicable Class A or Class B equivalent, less than 12% VSS content, low odor, high VAR, soillike characteristics Applicable Low metals, 16-30% Solids Site specific requirements may apply. Collaboration with landfill managers is required. There are incinerators accepting residuals, but availability and reliability of these outlets might be an issue

10 The available and viable solids outlets were identified and evaluated within the state of New Jersey and neighboring states. Outlets and end uses considered were within 150 miles from the city. The required solids characteristics for each viable outlet are shown in Table 5. Investigated outlets and end use options included incineration facilities, composting facilities, land application sites for either Class A (pellets or cake) or Class B cake, landfill facilities for use as a daily cover, and solids contractors. No pre-approved outlet has been identified for Class A and Class B cake land application in the area. There was only one NJDEP approved land application outlet which was accepting solely liquid residuals which was not a cost-effective method for the City. The reliability of each outlet is also included in terms of accepting long term contracts with the City of Millville. Both current and future hauling and end use costs were evaluated for the year of 2028 as shown in Table 6 - Existing and Future Hauling and End Use Costs Facility Gloucester County Utilities Atlantic County Utilities End use and hauling cost per wet ton in 2008 End use and hauling cost per wet ton in 2028 Annual Cost in 2028 $76.26 $ $1,550,707 $80.35 $ $1,633,969 GROWS (by Waste Management) $82.48 $ $1,677,284 Kent County Public Works $83.06 $ $1,688,989 Burlington County Composting Facility Somerset-Raritan Valley Sewerage Stony Brook Regional Sewerage $86.86 $ $1,766,265 $91.61 $ $1,862,859 $97.26 $ $1,977,755 Spectraserv, Inc. $ $ $3,658,496. As discussed earlier, the residuals are processed at ACUA facility at a rate of $64.28 per CY (including hauling) which translates to $80.35 per wet ton. For the existing solids production as listed in Table 1, the current annual cost of solids hauling and processing is estimated to be approximately $400,000. Hauling cost estimates are obtained from a contract hauler, Active Environmental Technologies for each site. The cost for each site is reported per wet ton. The range of hauling cost per wet ton is between $30 and $ Hauling costs were also estimated when City purchases a roll-off truck with hoist and two 30-CY dumpsters. Based on the quotes received from vendors, hauling biosolids by the City would cost $18.66 per wet ton plus the mileage ($0.8 per mile). In Table 6 - Existing and Future Hauling and End Use Costs

11 Facility Gloucester County Utilities Atlantic County Utilities End use and hauling cost per wet ton in 2008 End use and hauling cost per wet ton in 2028 Annual Cost in 2028 $76.26 $ $1,550,707 $80.35 $ $1,633,969 GROWS (by Waste Management) $82.48 $ $1,677,284 Kent County Public Works $83.06 $ $1,688,989 Burlington County Composting Facility Somerset-Raritan Valley Sewerage Stony Brook Regional Sewerage $86.86 $ $1,766,265 $91.61 $ $1,862,859 $97.26 $ $1,977,755 Spectraserv, Inc. $ $ $3,658,496, the cheapest hauling method by contract hauling, hauling by the City and hauling by the outlet facility, if available, was used. ALTERNATIVE CONFIGURATIONS Based on the available end use alternatives, solids processing alternatives at Millville facility were organized into two major categories: a) upgrading dewatering equipment to process future solids loads and to increase cake dryness, and b) adding a stabilization step to produce Class A biosolids. High cake dryness is required for incineration, landfill and composting. In addition to conventional dewatering technologies such as centrifuges and high solids belt filter presses, emerging technologies such as screw press and rotary press, and innovative technologies such as electrodewatering were investigated. Dewatering technologies that can be upgraded to produce Class A biosolids were also evaluated. Technologies producing Class A biosolids included ones that generate pellets such as belt dryers, and paddle dryers or cake such as screw press or digestion were considered.

12 Table 5 - Summary of Residuals End Use Options and Associated Costs Facility Atlantic County Utilities Burlington County Composting Facility Gloucester County Utilities GROWS (by Waste Management) Kent County Public Works Somerset-Raritan Valley Sewerage Spectraserv, Inc. Stony Brook Regional Sewerage End Use Mode Composting Landfilling Hi Temp/Hi ph Landfilling or beneficial use 1Based on 0.8 wet tons per cubic yard Location Pleasantville, NJ Colombus, NJ Thorofare, NJ Morrisville, PA Distance (miles) Accepted Solid Content Minimum Required Classification Tipping Fee per CY per wet ton 1 Hauling by facility? % Unstabilized $ $71.60 Yes % Unstabilized $52.32 $65.40 No Long Term Contract? Up to 5 years Up to 10 years % Unstabilized $44.80 $56.00 No No 80 >20% Class A or Class B $49.74 $62.17 Yes Up to 3 years Milford, DE % Unstabilized $48.00 $60.00 No Negotiable Bridgewater, NJ South Kearny, NJ Princeton, NJ 2 For the tipping fees of ACUA, existing 2008 rate minus $7 per CY hauling cost is used % Unstabilized $55.00 $68.75 No No 125 >20% Unstabilized $125.0 $ Yes % Unstabilized $60.00 $75.00 No Up to 15 years Up to 5 years

13 Table 6 - Existing and Future Hauling and End Use Costs Facility Gloucester County Utilities Atlantic County Utilities End use and hauling cost per wet ton in 2008 End use and hauling cost per wet ton in 2028 Annual Cost in 2028 $76.26 $ $1,550,707 $80.35 $ $1,633,969 GROWS (by Waste Management) $82.48 $ $1,677,284 Kent County Public Works $83.06 $ $1,688,989 Burlington County Composting Facility Somerset-Raritan Valley Sewerage Stony Brook Regional Sewerage $86.86 $ $1,766,265 $91.61 $ $1,862,859 $97.26 $ $1,977,755 Spectraserv, Inc. $ $ $3,658,496 After prescreening of technologies, eight different process configurations were established for Millville plant as listed below: Alternative 1: Replacing Existing Belt Filter Presses (BFPs) with Newer Machines Alternative 2: Replacing Existing BFPs by Centrifuges Alternative 3: Adding Electrodewatering (EDW) to the New BFP Units Alternative 4: Split PS and WAS Streams, dewater PS by BFP and dewater WAS by BFP followed by EDW Alternative 5: Split PS and WAS Streams, dewater PS by Rotary Press and dewater WAS by BFP followed by EDW Alternative 6: Replacing BFPs with Rotary Press Technology Alternative 7: Replacing BFPs with Screw Press Alternative 8: Constructing Anaerobic Digester followed by a Thermal Dryer (Class A) Alternative 5 where PS is dewatered by a 4 channel rotary press to about 30% and WAS is separately dewatered via the existing belt filter press followed by EDW to a targeted cake solids of 30% was not considered further. Even though both technologies are reported to have capability of dewatering more than 35% cake solids, there is no known outlet for un-stabilized

14 solids more than 30-35%. In addition, having three different dewatering technologies might pose an operational challenge to existing staff. Digestion would be essential in Class A biosolids production to avoid potential odor problems. One of the disadvantages of the digestion would be requirements of additional staff and full time operator attention, which would increase the operation and maintenance (O&M) costs. Moreover, the only prospective outlet for Class A sludge for now is Cumberland County Landfill. Prior proceeding with the design of facilities for Class A biosolids, approval would be required from both Cumberland County and NJDEP for the proposed characteristics of the cake and other design criteria. If the landfill can no longer accept the Class A biosolids for any reasons (potentially odor) in the future, no other outlets is available in the area. Based on this discussion, the processes for producing Class A biosolids (Alternative 8) was not further investigated. The City indicated that they would not install EDW units at this time due to high capital cost and structural modifications requirements. These two alternatives (Alternative 3 and 4) would be more viable upon Class A certification of the technology and when approved Class A outlets are found. For future reference, evaluations of these two alternatives were considered. COST ANALYSIS OF ALTNERATIVES The first part of this section summarizes the methodology used for the cost estimates. The next part provides details of capital and O&M cost for each alternative. Cost Estimating Methodology Capital and O&M costs were used to calculate the total present-worth value for each alternative. The following information was used to support the cost estimates: Vendor quotes and O&M cost estimates Operational cost estimates based on power and polymer addition requirements Assumptions on the disposal and hauling cost as necessary Conceptual layouts Planning level construction cost estimate Process flow diagrams For each alternative, a base line manufacturer has been selected. Budgetary quotes for major equipment items were obtained from manufacturers/vendors. Given the preliminary drawings provided by manufacturers/vendors, conceptual design layouts were developed. Approximate quantities for concrete, demolition, major yard piping, valves, etc. were calculated from the conceptual design layouts and used in planning level capital cost estimate. An allowance for electrical and instrumentation between 20 and 30% were used based on the nature of the upgrades and level of detail of the conceptual cost estimate line items. Contractor Overhead and Profit of 20% and contingency of 30% were also added to direct costs to reflect a planning level of detail.

15 Power and polymer addition requirements, along with annual maintenance cost estimate, were obtained from the manufacturers/vendors for O&M cost estimation. Contingency of 20% was used for the annual O&M cost estimate. A summary of capital and O&M costs for the several alternatives under considerations is shown in Table 7. Life cycle cost analysis (LCCA), consisting of capital and O&M present worth cost, was performed and compared among the six alternatives. A summary of the present worth analysis for each alternative is presented in Table 8. Based on the results of cost analysis, replacing existing BFPs with Rotary Press seems to be the most effective method followed by replacing BFP with centrifuge. As presented in Table 7, the most significant operational cost is end use and hauling cost, therefore, producing higher cake solids lowers the present value. DISCUSSION New Jersey is a densely populated state with minimal area committed for waste disposal; therefore, landfill disposition of biosolids is prohibited since it is considered a land-intensive method. This alternative is only permitted on a short-term basis under limited conditions. Even though NJDEP promotes beneficial use of biosolids, there is an increasing public resistance for land application of biosolids. Land application of Class A or Class B biosolids (in any form) is permitted in New Jersey, but the sites accepting new customers are limited. Most of generated Class A biosolids in NJ is either compost or pellet product. Unfortunately in-state land application of Class A or Class B biosolids in the form of cake solids is very limited. Current land appliers, other than the marketable biosolids producers, mostly use publicly owned sites such as county or city owned farms and woodlands. There is a concern within the City about not being able to use any City or County owned land for application of Class A or Class B biosolids. Therefore land application is not considered as a feasible option for the City of Millville at this point under these conditions. Preparing marketable products, such as fertilizers or soil amendments, is also practiced by some biosolids generators with varying degrees of failure and success. Our survey with marketable biosolids producers show that the Class A compost and pellets might be easier to find potential consumers in NJ. However, developing markets for biosolids products requires a careful strategy for marketing and educating customers. Marketing of the end product would require full-time staff attention or a private consultant as preferred by some Authorities. Use of biosolids or other marketable residual products in final landfill cover applications is the most preferred beneficial use method by the major biosolids producers in northern New Jersey. However there are no landfills currently accepting biosolids as daily cover in the southern New Jersey area. A protocol for biosolids use can be developed with the involvement of the landfill owners to utilize this alternative for the biosolids generated by Millville. Such protocol can be negotiated with the near-by landfills, owned by Cumberland County and Salem County. Prior to pursuing this track, it is required to collaborate with NJDEP to educate landfill managers regarding the benefits of using biosolids as a cover material. This practice can also benefit the landfill manager by reducing the cost of cover material.

16 Table 7 - Summary of Capital and O&M Costs Capital Costs Alt 1 BFP Alt 2 Centrifuge Alt 3 EDW Alt 4 EDW - Split Stream Alt 6 Rotary Press Alt 7 Screw Press Planning Level Construction Cost Opinion $1,710,800 $2,280,200 $9,101,300 $7,397,000 $1,693,900 $2,290,600 Annual Operation and Maintenance (O&M) Costs Daily Electricity and Polymer Consumption Electricity Consumption, kw-h/day 316 1,193 7,758 4, Polymer Consumption, lbs/day Electricity Cost, $0.095/ kw-h $30 $113 $737 $418 $37 $30 Polymer Cost, $1.52/day $148 $210 $148 $154 $148 $185 Daily End Use Cost (including hauling) Final Solids Concentration 21% 24% 35% 28% 24% 23% Total wet tons/day Hauling and Disposal Cost, $/w ton $69.80 $56.56 $56.56 $56.56 $56.56 $69.80 Daily Hauling and Disposal Cost $2,699 $1,914 $1,312 $1,640 $1,914 $2,519 Total Daily Operational Cost $2,877 $2,237 $2,197 $2,215 $2,099 $2,735 Annual Operational Cost $748,025 $581,578 $571,312 $345,561 $545,633 $710,981 Annual Maintenance and Part Replacement Cost $4,450 $12,000 $32,973 $31,523 $2,500 $3,000 ANNUAL O&M SUBTOTAL $752,475 $593,578 $604,285 $377,084 $548,133 $713,981 Contingency, 20% $150,495 $118,716 $120,857 $75,417 $109,627 $142,796 TOTAL ANNUAL O&M $902,970 $712,294 $725,142 $452,500 $657,760 $856,778

17 Table 8 - Summary of Present-Worth Analysis Alternative 1 New Belt Filter Press Alternative 2 Centrifuge Alternative 3 Electrodewatering (EDW) Alternative 4 EDW-Split Stream Alternative 6 Rotary Press Alternative 7 Screw Press Capital Cost Present Worth O&M Cost Total Present Worth Cost $1,710,800 $15,502,771 $17,213,571 $2,280,200 $12,229,119 $14,509,319 $9,101,300 $12,449,699 $21,550,999 $7,397,000 $7,768,817 $15,165,817 $1,693,900 $11,292,836 $12,986,736 $2,290,600 $14,709,706 $17,000,306 is a viable option for solids processing, however, a reliable outlet or incineration facility should be used since the City has to seek alternative routs due to unforeseeable shut downs of the incineration facilities. Thus, alternate outlets under these conditions are also needed to be identified and contracts should be negotiated with these outlets for accepting solids. CONCLUSIONS The study showed that the biosolids management option for a medium sized plant in southern New Jersey is very challenging due to the availability of outlets and state regulations. Alternatives producing Class A biosolids were not considered after conducting the market study since there are no viable Class A outlets. The most viable biosolids end uses were identified as incineration and composting facilities. Thus, producing drier cake solids and not stabilized biosolids becomes the main goal of the solids management program for the City of Millville. The dryness should not exceed 30% since finding outlets would be difficult above this range. Based on findings from this study, the City is considering conducting a pilot study of the top two alternatives, possibly side-by-side, prior to final selection and design. References NJDEP (1998) Technical Manual for Residuals Management. Trenton, NJ. New Jersey Administrative Code (N.J.A.C. 7:14A-20), Standards for the Use or Disposal of Residuals. NJDEP (2005) State Wide Solid Waste Management Plan Trenton, NJ.

18 NJDEP (2006) Sewage Sludge Production by Management Mode.. Trenton, NJ. AECOM (2009) Sludge Planning Study Report for City of Millville. Philadelphia, PA