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HomeMy WebLinkAboutBethel Heat Recovery Conceptual Design Report Rev B - Jan 2018 - REF Grant 708118Bethel Power Plant Heat Recovery System Upgrades Conceptual Design Report Prepared For: Prepared By: Coffman Project # 161426 Rev Description By Reviewed Approved Date A Draft, Issued for Review J. Zak M. Miller T. SlatonBarker 9/27/17 B Updated per Review Conf.J. Zak M. Miller T. SlatonBarker 1/18/18 AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 1 Rev B TABLE OF CONTENTS 1. PURPOSE ............................................................................................................... 2 2. SCOPE OF WORK ................................................................................................... 2 3. REPLACEMENT PIPE MATERIALS ......................................................................... 3 3.1 INSULATED PLASTIC PIPE .............................................................................................................. 3 3.2 INSULATED STEEL PIPE ................................................................................................................. 4 4. PIPELINE SUPPORTS ............................................................................................. 5 4.1 PIPELINE SUPPORT MODELING ...................................................................................................... 5 4.2 PILE SUPPORTS .............................................................................................................................. 5 4.3 SLEEPER SUPPORTS ....................................................................................................................... 5 4.4 HELICAL PILES .............................................................................................................................. 6 4.5 BURIED PIPE .................................................................................................................................. 6 5. VALVES & MAINTENANCE .................................................................................... 6 5.1 PIPELINE MAINTENANCE ............................................................................................................... 6 6. PIPE SIZING .......................................................................................................... 6 7. EXPANSION/CONTRACTION .................................................................................. 8 7.1 INSULATED PLASTIC PIPE .............................................................................................................. 9 7.2 INSULATED STEEL PIPE ................................................................................................................. 9 8. COST ESTIMATE ................................................................................................... 9 9. CONCLUSION ...................................................................................................... 10 9.1 CONSTRUCTION ........................................................................................................................... 10 9.2 OPERATIONS ................................................................................................................................ 11 9.3 ECONOMICS ................................................................................................................................. 11 10. APPENDICES: ...................................................................................................... 12 Appendix A: Conceptual Drawings Appendix B: Pipeline Calculations Appendix C: Cost Estimates Appendix D: Pricing Data AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 2 Rev B 1. PURPOSE Alaska Village Electric Cooperative (AVEC) has engaged Coffman Engineers (Coffman) to explore options to replace the heat recovery pipeline system in Bethel, Alaska, including piping, insulation and the support structure. The purpose of this report is to describe the methods used in the evaluation. This report builds on prior analysis (completed in 2017) that included a review of pipeline and foundation integrity, current and potential customer loads, heat output available from the power plant, and related engineering considerations. 2. SCOPE OF WORK The existing heat recovery system is an above ground insulated steel pipeline, approximately 2.3 miles in total length. System pumps are located in the heat exchanger module (installed in 2017), located on the AVEC power plant property. Each customer facility is equipped with a heat exchanger separating the recovered heating system from the facility boiler/heating loop. The system was originally constructed in 1976, and has been in operation for more than 40 years. The heat exchanger module, installed in 2017, represents a significant investment to ensure continued reliability of the system. The pipeline itself has not seen significant investment and is nearing the end of its useful life. There are many areas where the pipe and the pipe supports have either failed or the condition cannot be accurately verified with conventional means. A portion of the original system is currently out of service and isolated from the current operating system. This out of service section provided heat to four buildings. This report considers pipeline replacement options to obtain 20 years of additional service. In order to plan for anticipated capital constraints, the scope of work to replace the system has been broken into three phases. Plastic and steel piping are considered. See section 3. Figure 1. Phasing Plan AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 3 Rev B Phase 1 This phase will replace of the supply and return piping and piles from the new heat exchanger module at the power plant to the service connection to the hospital. 8-inch diameter steel piles will be installed at 20-foot spacing to support the replacement piping. Phase 2 This phase will replace the supply and return piping from the intersection of the phase 1 piping at the northeast corner of the powerplant property (see Figure 1) to the service connection for the correctional facility. The existing piles will be replaced with either new piles or pressure treated timbers on-grade. Both foundation systems are included in this analysis. Phase 3 This phase will replace the supply and return piping and piles from the hospital service connection to the termination of the recovered heat system near the courthouse. The replacement piping for this phase will be supported on steel piles with a 20-foot spacing. Branch Piping Branch piping replacement costs are included separately in this analysis because the cost of new branch piping may be negotiated between AVEC and each customer. 3. REPLACEMENT PIPE MATERIALS Two material options are considered to replace the existing insulated steel pipe of the recovered heat system. The first material is a plastic pipe and the second material is steel pipe. Regardless which material is selected, the pipe material will be delivered to the field pre-insulated with an outer covering (jacket). The insulation layer will be the same for each pipe material, a 3 lb/ft3 urethane foam. The jacket material will depend on which pipe material is selected. 3.1 INSULATED PLASTIC PIPE The plastic pipe being proposed is produced by Nupi and is a Random Copolymer Polypropylene (PP-RCT) material with a fiberglass reinforcement layer. The fiberglass layer reduces the amount of expansion and contraction by approximately 75% when compared to a monolayer of PP-RCT. The product name is Nupi Niron Clima SDR11. Similar restrained plastic pipe is available from a range of manufacturers. This material is suitable for relatively high temperature service (180oF @ 100PSI), as required for the engine jacket water heat recovery system. See Figure 2. AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 4 Rev B Figure 2: Nupi Niron PP-RCT Piping Sustained Pressure vs. Temperature (Niron D&I Manual 2016) The deadhead pressure of the system pumps (Figure 4) installed in the new heat recovery module is a system design pressure of 91 PSI is reasonable. Typical operating pressure is less than 75PSI. Therefore, the product appears to be suitable for this application from a pressure containment perspective. One major drawback to the PP-RCT material for an above grade, outdoor application is that the maximum unsupported pipe span is limited to 6-7ft, given the average system operating temperature of 180F. To overcome this limitation, a heavy gage corrugated metal pipe (CMP) was selected as the jacket. The jacket will be the primary support member for the system, allowing the plastic pipe to span 20-feet between piles. For the design of the jacket, the recommendations of the Corrugated Steel Pipe Design Manual (CSPDM) were followed. The CSPDM recommends to model CMP as a thin walled steel pipe for aerial applications. To be conservative the plastic pipe and the insulation are considered dead weight and offer no additional strength or stiffness to the insulated pipe. 3.2 INSULATED STEEL PIPE The steel pipe being proposed is ASTM A53 Grade B schedule 40 material with welded joints. In this case, the steel pipe can self-support across 20-foot spans. The steel inner pipe will be the primary load carrying member of the system. Since jacket strength is not a driving factor, a thin walled HDPE sleeve will be provided to protect the insulation. The insulated pipe was modeled with the HDPE jacket and the insulation considered as dead weight. The potential for corrosion is the largest concern with respect to a steel piping system. To mitigate this risk, the insulated steel pipe is priced with an industrial quality coating system to prevent corrosion. The coating system is a fusion bonded epoxy (FBE) or similar system, typically used in regulated pipeline systems transporting hydrocarbons, both above and below grade. While there are no known regulatory requirements for the design or construction of this recovered heat system, the technology developed for the regulated pipeline industry is considered applicable for this installation AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 5 Rev B and, if properly applied, will result in a coating system that protects the piping with little or no annual maintenance. The cost of this coating system is included in the cost estimates. An internal pipe wall coating is not anticipated as AVEC treats the circulated water with a corrosion inhibitor. Continued treatment and monitoring of the fluid is expected to continue for the life of the project. The existing uncoated steel piping system has been in operation for over 40 years with minimal internal corrosion noted. 4. PIPELINE SUPPORTS Based on a prior geotechnical investigation of the subsurface conditions along the pipeline route (Golder, 2016) two types of supports are being proposed for this system. Phase 1 and Phase 3 piping will be supported on driven piles. Phase 2 piping is evaluated with two different foundation types: driven piles and wood sleepers at grade. Helical piles were evaluated as well, as discussed in Section 4.4. If pressure treated timber sleeper supports are used, a limited number of driven piles will still be required in certain areas (expansion loops, valve boxes). Support spacing for all three phases is set a 20-feet due to material limitations. Increasing pile spacing would result in additional cost of heavier wall or larger diameter piping or additional horizontal piping support members. We would expect these costs to offset the savings associated with fewer piles. 4.1 PIPELINE SUPPORT MODELING To determine the maximum support spacing, the insulated steel pipe and insulated plastic pipe were analyzed using structural modeling software. In addition to the self-weight of each pipe and the contents of the carrier pipe, each pipeline was modeled with a full snow load. Wind and seismic were not included in the pipe modeling, as the vertical loading from snow and the pipe weight are the controlling load case. To be conservative, the insulated plastic pipe system was modeled as simply supported spans from one support to the adjacent support. This approach does not directly match the anticipated field conditions but provides a conservative approach to system design. For the plastic pipe, it is anticipated that each pipe segment (40-foot) will be supported by a minimum of three piles. There will be a pile at each end and one near the center. Having the pipe span over a center support increases its structural capacity beyond how it was modeled. The welded steel pipe was modeled as continuous over all supports. The only break in continuity is at each service connection. See appendix A for the calculations. 4.2 PILE SUPPORTS The driven piles will consist of 8-inch diameter schedule 80 steel piles at a maximum spacing of 20- feet. Based upon the location and depth of permafrost in the area, typical piles will need to be driven to a depth of 40-feet. In phase 3, in the vicinity of the KCC dorm and the cultural center, the piles will need to be driven to a depth of 75-feet due to swampy conditions. All piles will extend above ground approximately three to five feet to support the pipeline. Piles will extend higher where needed, such as at expansion joints and as to account for surface elevation changes. 4.3 SLEEPER SUPPORTS In phase 2 of the project there is an opportunity to use pressure treated timbers installed directly on the ground surface to support the pipeline, due to relatively dry surface conditions. Each timber will have the organic layer removed below it and a well graded gravel backfill installed to minimize the movement the pipeline will experience. The pipeline will be attached to the timber sleepers. Each timber will be staked to the ground to prevent lateral movement of the pipeline. Additional sleepers will also have a soil anchor where determined appropriate by design conditions and terrain. The AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 6 Rev B timber sleeper foundation is likely to require increased maintenance compared to a pile foundation to readjust pipeline alignment after jacking and/or settling. 4.4 HELICAL PILES The geotechnical report recommends helical piles to be installed in the thawed areas where a driven of a 6-inch diameter steel shaft with a single 16-inch diameter helix with an embedment of 20-feet. Helical piles were not considered in this phase of the project due to uncertainty in the installation costs. Quotes from STG ranged from $3,800 to $5,500 per pile depending on installation conditions. Estimated costs for driven piles at 40-foot depth $3,800. Once the project has proceeded to a detailed design, helical piles can be more fully evaluated as an installation option. 4.5 BURIED PIPE The entire pipeline system is above grade, except for the two branches that serve the correctional center (jail) and the courthouse. Buried piping is routed below the active layer, and is contained within additional blueboard insulation in order to minimize heat dissipation to the surrounding soils. Coordination with geotechnical engineer is required to finalize the trench detail for these segments to minimize impact to the permafrost and obtain the best long-term performance. 5. VALVES & MAINTENANCE Branch valves are provided at each customer branch connection. Valves will be located in an insulated, pile-supported enclosure, see Appendix A. Exposed valves and branch connections are also feasible, but are expected to result in a less robust installation, reducing reliability and increasing maintenance costs. 5.1 PIPELINE MAINTENANCE Provisions for inline inspection (ILI) are not included in this cost estimate. Butterfly valves are used throughout, which matches the existing design, but would not allow passage of an inline inspection ce or inspection activities would happen from outside the pipe. Some inspection methods, such as ultrasonic testing, would require removal of the jacket and insulation. Cathodic protection is not anticipated for this system. Active or passive cathodic protection systems can be considered for buried piping segments, which only occur on branch segments serving the jail and the courthouse. However, it is likely more cost effective to use plastic piping for any buried segments. 6. PIPE SIZING The existing recovered heat system consists of approximately 12,000 lineal feet (2.3 miles) of piping. All mains being Previously completed energy modeling analysis provided an estimate of building heat loads for current and future customers. The modeling results indicate that the size of mains and many branches identified future customers. Minimum sizing recommendations for schedule 40 steel pipe, sized to meet the estimated peak demand at each customer facility is shown in Figure 3. Steel piping of the same nominal pipe size has a smaller wall thickness and larger inside diameter compared to the plastic pipe that is suitable for this AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 7 Rev B service. Pipe sizing should be reviewed and adjusted depending on final material selection, system diversity assumptions, and spare capacity for any future expansion that is not currently modeled. Figure 3 - Minimum Steel Pipe Sizing for Recovered Heat Mains The total system friction loss including piping, AVEC heat exchangers, customer heat exchangers should be compared to the pumping capability of the three new system pumps: 950 GPM @ 130ft of head, with 102ft of head loss attributable to the distribution system. Additional head is available because the total pump capacity (2850 GPM) is 15% higher than the calculated peak flow rate of 2405 GPM. The pump curve is shown in Figure 4 for reference. AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 8 Rev B Figure 4 - Recovered Heat System Pump Curve (typical of 3 parallel pumps) Plastic piping suitable for this application has a significantly thicker wall than comparable steel pipe. For example, 10-inch Nupi Clima SDR11 plastic pipe has a wall thickness of 0.89-inches, and an inside diameter of 8.05-inches. For reference, ANSI Schedule 40, 8-inch steel pipe has an inside diameter of 7.98-inches. In a typical application in the size range required for this system, plastic piping would be selected one pipe size larger than steel pipe, which is a conservative way to equalize friction loss between the two material options. During detailed design, pipe sizing can be refined and may be reduced by one pipe size in some locations without having detrimental system impacts. Branch pipe sizing is assumed to be 4-inch for all branches, except the hospital. This method over- sizes some of the branches. However, if multiple customers are connected under one construction project, using a single pipe size will reduce risk and waste during construction. These reductions will be reflected in the bid prices and are expected to offset the higher material cost. If individual customers are connected, pipe sizing should be reviewed and adjusted to meet that cust 7. EXPANSION/CONTRACTION Control of the expansion and contraction of the recovered heat system is critical to keep from damaging the valve boxes and keeping the pipe joints on the supports. The expansion and contraction of the pipeline will be based on the installation temperature, lowest expected temperature (typically during a pipeline shutdown) and the operating temperature of the system. For the pipeline, the following design conditions have been determined to apply: AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 9 Rev B Design Temperatures Low Temperature: -40°F Installation Temperature: 40°F Operating Temperature: 180°F Table 1: Design Temperatures The pipeline will be designed to accommodate expansion corresponding to a temperature differential of 140°F and contraction corresponding to a temperature differential of 80°F. Two methods are proposed to control the expansion and contraction of the system. Both methods depend on the natural ability of the pipe to flex at bends in the pipe. Where bends happen naturally along the pipe, they will be used as a natural spot to allow the pipeline to grow and contract. Where there are long straight sections or where there are no bends between two valve boxes, an expansion loop will be required. The expansion loops will consist of elevated sections of pipe that are offset vertically from the main alignment. Horizontal expansion loops can be considered in areas that have adequate space available within the easement. Limited numbers of pipe anchors or guides may be required so that pipe expansion is directed into the desired section of piping Expansion loops are built from the same material and jointing method as the rest of the pipeline. Offset distance, guides, and anchoring are designed to control movement in order to prevent damage to valve boxes, piping, joints, and supports, and to ensure that pipe supports remain aligned on the foundation system under all foreseeable scenarios. 7.1 INSULATED PLASTIC PIPE Plastic pipe typically expands and contracts a large amount when the temperature changes. The plastic pipe proposed for this project reduces this movement by a significant amount but still exceeds the thermal expansion rate of steel pipe. Per 100-feet of pipe, given a temperature change of 140°F, the PP-RCT pipe will grow by 3.3-inches. Expansion compensation joints, change in direction will need to be installed at intervals of less than 500-feet. Although expansion compensation will be sized to handle the full calculated movement of the plastic pipe, the insulation and jacketing are expected to provide some restraint, which in practice will reduce the movement of the composite arctic pipe. 7.2 INSULATED STEEL PIPE Steel pipe typically does not have as significant an issue with expansion and contraction as plastic pipe. Per 100-feet of pipe, given a temperature change of 140°F, the pipe will grow by 1.4-inches. For the recovered heat system, controlling the expansion/contraction between valve boxes will be critical. For straight sections between bends, expansion loops will need to be installed at approximately 1000- foot intervals. Elevating valve boxes to introduce offsets may be an effective way to address thermal expansion in areas where multiple valve boxes will be installed in close proximity, such as on the South Loop. 8. COST ESTIMATE A cost estimate using each of the replacement pipe materials was produced for each of the three project phases. Vendor quotes were obtained for the pre-insulated plastic pipe, pre-insulated steel pipe, associated pre-insulated fittings and driven piles. The cost for installation was estimated based AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 10 Rev B on an anticipated crew size and duration. The full estimates can be found in Appendix C. Pricing information from vendors can be found in Appendix D. Each phase and each branch were estimated independently. If multiple phases are constructed concurrently, general conditions and mobilization costs could be shared, thus reducing the total cost. pipe sizes for branches may be possible during detailed design. However, jacket size and thickness, as well as pile spacing needs to be considered as smaller diameter piping typically requires more supports at smaller intervals. Rough Order of Magnitude (ROM) Construction Cost Summary Table Pipe Length Plastic Pipe Steel Pipe [ft] [$] [$] Phase 1 680 $757,100 $675,000 Phase 2 with Piles 2,600 $1,560,200 $1,547,900 Phase 2 with Sleepers 2,600 $1,274,700 $1,270,200 Phase 3 6,840 $4,748,200 $4,619,200 Branch Lines Phase 1 YKHC Hospital (Branch A) 880 $413,200 $423,400 Phase 2 800 Building (Branch J) 200 $80,500 $77,200 Youth Facility (Branch I) 1,120 $376,900 $351,200 Correctional Facility (Branch K) 760 $376,400 $370,400 Phase 2 - All Branches 2,080 $833,800 $798,800 Phase 3 KCC Dorm (Branch B) 200 $70,600 $77,400 UAF Complex (Branch C) 80 $27,000 $30,600 Cultural Center (Branch D) 80 $27,000 $30,600 PATC Annex (Branch E) 40 $11,500 $14,400 Fire Station (Branch P) 80 $25,800 $29,500 PATC (Branch F) 40 $12,600 $15,500 City Hall (Branch G) 120 $38,200 $40,400 Courthouse (Branch H) 120 $38,200 $41,600 Phase 3 - All Branches 760 $250,900 $280,000 Table 2: Construction Cost Estimate Summary The cost estimates indicate that plastic and coated steel piping systems are comparable in price. Pricing for the two material options differs less than the margin of error of the estimates (+/- 30%). 9. CONCLUSION 9.1 CONSTRUCTION As shown in Section 8, the capital cost for a replacement pipeline is comparable for steel and plastic piping systems. Tradeoffs in material cost, freight, and installation labor costs balance out within 12% of the total estimated cost for all phases and nearly all branches. AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 11 Rev B Due to the limited width of the existing easements along the recovered heat right of way, the current design basis anticipates that construction of the new pipeline will require prior demolition of the existing pipeline, resulting in a significant downtime during construction. We anticipate that piles can be driven prior to demolition, so the downtime will occur during summer or fall, at a time that minimizes inconvenience for AVEC. During Phase 1 construction, temporary heat can be provided to the Phase 2 customers with temporary piping, while Phase 3 piping may need to be kept warm by supplying heat through a customer heat exchanger. Cost for temporary facilities are not currently included in the cost estimates, pending further clarification of the requirements. It is recommended that additional analysis occur once the replacement scope, pipe, and support structure are determined, to see if there are options to install the new system while the existing system is still operating. 9.2 OPERATIONS There is no discernable difference in operational costs between the two proposed pipe materials. The potential for steel corrosion is the largest concern between the two proposed pipe materials. To mitigate the corrosion risk for steel piping, an industrial quality coating system is included in the cost estimates. It is expected that for a 20-year life, there should be no significant corrosion issues on a steel pipe system that is properly coated, installed and maintained. Pumping energy is expected to be similar between the two systems. Plastic pipe is selected with a larger nominal diameter in order to keep the inside diameters approximately equal, resulting in equivalent friction loss comparable between the two options. Maintenance for either system is expected to be minimal. Repair of plastic and steel piping systems would each require a temporary shelter for repairs in inclement weather. Another factor to consider is the limited pressure and temperature range of the plastic pipe. Care will need to be taken to keep water temperature and pressure within manufacturer requirements. The longevity of the pipe will be reduced if temperatures and pressures are elevated during operation. 9.3 ECONOMICS The economic value of the project is evaluated below, based on projected heat sales. The sales price is assumed to be consistent across all customers, at $21 per million BTU (MMBtu). The connected load (Alternatives Analysis and Energy Modeling Report, March 2017). AVEC Bethel Heat Recovery System Upgrades Jan 18, 2018 Conceptual Design Report Page 12 Rev B Projected Annual Sales and Payback by Phase Phase 1 Phase 2 Phase 3 South Loop Expansion Peak Connected Load [MMBtu/hour] 12,000 16,100 20,400 24,600 Connected Heat Demand [MMBtu/year] 38,600 50,900 61,800 77,200 AVEC provided Heat [MMBtu/year] 38,600 50,700 60,200 71,700 AVEC Sales @ $21/MMBtu [$] $ 810,000 $ 1,060,000 $ 1,260,000 $ 1,510,000 Marginal Sales Increase per Phase [$] $ 250,000 $ 200,000 $ 250,000 ROM Estimated Construction Cost* [$] $ 675,000 $ 1,548,000 $ 4,620,000 N/A Simple Payback [Years] 0.8 6.2 23.1 N/A *Note: Construction Cost listed for Mains only, branch piping costs are excluded. Table 3: Projected annual sales and simple payback by project phase continued ability to serve its recovered heat customers in operation. Continued operation of the existing system is feasible at this time, in which case any capital investment would not provide a positive value for AVEC. Although annual revenue will vary based on fuel costs and weather, Table 3 clearly shows that a phased approach is appropriate for upgrading the recovered heat pipelines, with phasing established to ensure that the piping serving the largest customers and those customers nearest to the powerplant is replaced on a priority basis. The expanded hospital is by far the largest customer, with more heat sales than all other identified customers combined. Replacing piping to the hospital shows a payback of 0.8 years. Phase 2 appears to provide a reasonable payback period. A more detailed economic evaluation may be warranted , fuel cost projections, and the estimated remaining of life of the existing pipeline. Phase 3 appears not to be an economic project as the marginal increase in heat sales would not pay off the cost of construction within a reasonable timeframe. 10. APPENDICES: Appendix A: Conceptual Drawings Appendix B: Pipeline Calculations Appendix C: Cost Estimates Appendix D: Pricing Data Anchorage, Alaska 995034831 Eagle Street Anchorage, Alaska 995034831 Eagle Street Anchorage, Alaska 995034831 Eagle StreetRECOVERED HEAT SYSTEM SITE PLAN / SHEET INDEX Anchorage, Alaska 995034831 Eagle StreetENLARGED PLAN Anchorage, Alaska 995034831 Eagle StreetENLARGED PLAN Anchorage, Alaska 995034831 Eagle StreetENLARGED PLAN ENLARGED PLAN Anchorage, Alaska 995034831 Eagle StreetENLARGED PLAN ENLARGED PLAN ENLARGED PLAN Anchorage, Alaska 995034831 Eagle StreetENLARGED PLAN Anchorage, Alaska 995034831 Eagle StreetENLARGED PLAN Anchorage, Alaska 995034831 Eagle StreetENLARGED PLAN - BRANCH K ENLARGED PLAN - BRANCH I Anchorage, Alaska 995034831 Eagle StreetENLARGED PLAN - BRANCH A Anchorage, Alaska 995034831 Eagle StreetINSULATED PIPE DETAIL HALF SHELL DETAIL COUPLING BAND PIPE SUPPORT DETAIL @ JOINT CUSTOM FITTINGS TYPICAL PILE ELEVATION PIPE SUPPORT ELEVATION @ MID-SPAN PIPE SUPPORT PLAN @ MID-SPAN PIPE SUPPORT ELEVATION @ COUPLING BAND PIPE SUPPORT PLAN @ COUPLING BAND Anchorage, Alaska 995034831 Eagle Street Anchorage, Alaska 995034831 Eagle StreetINSULATED VALVE BOX PLAN - BRANCH VALVES ONLY INSULATED VALVE BOX PLAN - BRANCH & MAINLINE VALVES INSULATED VALVE BOX SECTION PIPE COLLAR DETAIL REMOVABLE LID DETAIL Anchorage, Alaska 995034831 Eagle StreetSLEEPER SUPPORT OPTION, TYPICAL PLAN SLEEPER SUPPORT OPTION, TYPICAL ELEVATION SLEEPER SUPPORT SECTION Anchorage, Alaska 995034831 Eagle StreetTRENCH SECTION Anchorage, Alaska 995034831 Eagle StreetEXPANSION LOOP PLAN (PHASE 1 AND 3) EXPANSION LOOP ELEVATION (PHASE 1 AND 3) Anchorage, Alaska 995034831 Eagle StreetEXPANSION LOOP PLAN (PHASE 2) EXPANSION LOOP ELEVATION (PHASE 2) QuoteSls Order:Attn: QuoteSls Order: QuoteSls Order: QuoteSls Order: QuoteSls Order:Attn: QuoteSls Order: QuoteSls Order:Attn: QuoteSls Order: QuoteSls Order: