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Alternatives Analysis Alternatives Analysis 1.0 Introduction The Syncarpha Northampton Community Solar Project is proposed on a parcel of land that features resource areas protected under the Massachusetts Wetland Protection Act, M.G.L. c. 131, §40, as well as the Northampton Wetlands Protection Ordinance, Chapter 337. The overall property features Bordering Vegetated Wetland (“BVW”) areas as well as a 200-foot Riverfront Area that surrounds Hannum Brook, a perennial stream that traverses the site generally from northeast to southwest. The site is currently an open meadow with a stand of white pine trees in the central location of the site. The meadow features a perimeter of mature tree and shrub growth which forms a visual barrier to the protected resources from the meadow portions of the site. Hannum Brook and the wetlands cannot be viewed from the meadow. The stand of white pine trees is outside of the jurisdictional limits of the Wetland Protection Act and the Northampton Wetlands Protection Ordinance. As a result of the design of the project, ground disturbances within the jurisdictional limits will be limited to the installation of the support tables for the solar panels, the installation of the fence line (a minor activity) and planting of trees (a minor activity). Based on 310 CMR 10.02(2)(b)2.b., the fencing within the jurisdictional area is considered a minor activity and not regulated provided that it does not constitute a barrier to wildlife movement. Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 2 Wetland Program Policy 17-1, page 4 indicates that “if fencing is proposed, the fence shall be at least 6-inches off the ground to provide for wildlife passage for the length of the fence. In addition, 310 CMR 10.02(2)(b)2.d allows the planting of “native species of trees, shrubs or groundcover…” within the jurisdictional area as a minor activity that is not regulated. The overall property will be divided into four individual lots. Parcels A and B will become two individual lots (2.9+ and 2.8+ acres, respectively) that will be retained by Syncarpha and have frontage on Park Hill Road. Parcel C will be donated to the City of Northampton (14.7+ acres) and Parcel D will be the site of the proposed solar facility (17.1+ acres). 2.0 Project Goals The proposed project has been approved by National Grid to provide up to 5.0 MW of power to the existing grid. The cost of the upgrades to the National Grid system is fixed at $1.4 Million and the cost of the land is also fixed. These fixed costs will not slide in scale as the proposed facility’s output changes. A smaller facility will not result in lower land costs or lower National Grid system improvements. In order for the project to remain economically feasible, it will be important to maintain a total output as close to 5.0 MW as Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 3 possible. The original layout provided approximately 4.0 MW of solar output. While that is below the original project goal due to the layout restrictions presented by the natural resource areas, the project proponents are comfortable with the total number of panels proposed for the project. To help reduce project construction costs to accommodate the reduction of solar output to below 5.0 MW, the project has been designed to be able to be built upon the existing land with minimal amounts of tree removal and grading of the existing topography. Placement of the system within the existing wooded perimeter helps to achieve this goal by minimizing land clearing and utilizing existing cleared areas of meadow. The original project sought approval for the installation of fencing and support structures for solar panels within the 100-foot buffer to the BVW and the 200-foot Riverfront Area. The project also includes the planting of trees in the regulated area to satisfy the requirements of the City of Northampton’s Significant Tree Ordinance. The support tables will be installed by pushing a three-inch diameter support pole into the ground, or through the use of a ground screw that will be three inches in diameter. This will occur at each corner of the support table. No excavation or soil removal will be required. In most instances, the existing vegetation will remain in place. The installation of these supports will not require any grading or alteration of the ground surface. The existing meadow grasses would be left intact and allowed to grow to the height of the low end of the panels (three to four feet). The panels will be placed on the completed support structures and will be a minimum of three to four feet above the ground surface. Once installed, the panels will produce shading impact to the ground directly below the panels themselves. The rows of panels are spaced approximately fifteen (15) to twenty (20) feet apart in order to eliminate shadows on the panels themselves, and this spacing provides a break from a completely shaded area that allows vegetation to remain intact under the panel structures. 3.0 Site Selection Before even approaching landowners in Northampton, Syncarpha conducted internal due diligence related to the interconnection feasibility of regions within the City of Northampton. Using the National Grid interconnection queue as well as three phase mapping, they selected parcels of land that were determined to have the greatest chance of receiving an Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 4 interconnection service agreement from National Grid with reasonable upgrade costs. Since solar has been so popular within the Commonwealth for the last 5 years, the grid (especially National Grid's service territory) has become extremely saturated -- pushing many distribution lines, feeders, and substation transformers to their absolute maximum capacities. As a result, just because a parcel of land is located near three phase power, solar developers can no longer automatically assume the site can be interconnected -- hence the aforementioned due diligence. Once interconnection feasibility was determined, Syncarpha then further eliminated sites based on certain environmental concerns. For example, they tried to avoid sites that would require substantial grading and clearing; sites with major wetlands concerns; sites within the 100- yr floodplain; etc. Taking all of that into consideration, they ultimately reached out to ten (10) landowners in Northampton via mailers and phone calls to gauge their interest in solar development. Based on that outreach, the only landowner that was interested (and they could reach commercial terms with) were Kenneth and John Burt, the current owners of the selected property. 4.0 Avoidance 4.1 Use all available upland areas for PVS arrays and other project components The original project featured a panel layout that was entirely within the meadow area without removing any of the perimeter tree line. This layout resulted in panels and fencing being placed within the Riverfront Area and within the 100-Foot buffer to the BVW. This layout resulted in the placement of 37,195 square feet of panels within the Riverfront Area. Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 5 The total land area within the fence line in this area was 113,653 square feet. No other project components (access drives, transformer pads, utility poles, duct banks, etc.) would be placed within the Riverfront Area. The revised layout has shifted several support tables out of the Riverfront Area and relocated them to the south and east perimeter of the project site. This will result in the increased removal of trees in the southeast corner of the site. Approximately forty-five (45) trees over twelve (12) inches in diameter would need to be removed, including eleven (11) additional “significant trees” that are over twenty (20) inches and will require replacement under the Northampton Ordinances. The shift in layout results in the reduction in panel placement in the Riverfront Area to 16,468 square feet. The area within the fence line will be reduced to 58,912 square feet. For the purposes of the permit, the disturbed area should be limited to the area that will be directly under the Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 6 panels only since no other disturbances are proposed within the fence line. As with the original proposal, no other project elements are proposed within the resource areas. The revised panel layout provides the utilization of the maximum area of upland for the proposed panels. 4.2 Review alternative interconnection locations and types available to the solar facility for connecting the solar PV system to the grid. The interconnection for the solar facility will include the placement of electrical duct banks within the existing gravel road structure and will not result in any new disturbance within the resource area. The three-phase power will need to be extended from Glendale Avenue at the site of the interconnection of the solar facility to the north, along Glendale Avenue to Park Hill Road and down to the end of the pole line on Park Hill Drive. This will all be with overhead wires. The City of Northampton seeks to eliminate as many new poles as possible and has requested that the interconnect from the site to the las pole on Park Hill Road be located underground. An alternate route would provide a shorter run of three phase power by connecting to the existing pole line that originates at the solar facility to the north. This would require crossing of Hannum Brook and the placement of utility poles in the BVW and the Riverfront Area. This would not be an environmentally feasible alternative. A second alternate route would be to run the interconnect to the east along Park Hill Road and connect to the three-phase power located along Oliver Street in Easthampton at the solar facility Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 7 to the south. This represents a longer underground run which would be much costlier and may require additional upgrades to the National Grid system. The proposed interconnect appears to provide the most environmentally feasible alternative. 4.3 Reduce the size of the array through elimination of some panels, the use of fewer, more efficient panels that generate a greater amount of electricity or reducing the spacing between panels and tables while maintaining project viability. The size of the PVS array was originally reduced to fit within the confines of the existing meadow and remain in areas that presented minimal risk of impacts to the resource areas. The use of 345- watt panels provides for the use of fewer panels than the less expensive 300 to 310-watt panels that are in use on many arrays. Panel spacing between rows has been minimized to the extent practicable to prevent shadows on adjacent rows of panels. Any additional reduction in the space between the rows of panels would result in shadow impacts and would reduce the efficiency of the overall array. The revised layout of the panel system retains the use of the 345-watt panels and does not change the row spacing across the various locations on the overall site. The placement of the panels in the southeast corner and the shifting of the maintenance road to the south allows for the relocation of many panels from the resource area to the upland areas. 5.0 Minimize 5.1 Evaluate the use of high efficiency panels (e.g. panels that track the sun) and locating panels in a manner that reduces the need for future vegetation management and wetland alteration. The use of panels that track the sun presents a significant increase in project cost ($0.05 to $0.10 per watt, or $250,000 to $500,000 for very little gain in efficiency. The reason for this is that for locations in Massachusetts, the angle of the sun is such that the increase in efficiency is very minor. In other parts of the country, this technology is more feasible. Another drawback to using the tracking panels is that the installation of those systems requires a flat site, which would Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 8 require more earthwork and more overall land disturbance for the project, as well as a dramatic increase in project costs. The final issue with the use of tracking panels is that the aerial requirement for these systems is typically 1.5x to 1.75x larger than the systems that use the stationary panels for the same power output. The overall footprint would grow dramatically to maintain the same output. The tracking panels are typically a good choice on very large flat locations in other parts of the United States. Future vegetation management within the resource areas will not be necessary. The existing tree line to the north and west of the site within the resource areas will not need to be trimmed or managed through the life of the project. Due to the way the project has been sited within the existing meadow, trees along the perimeter would not have required removal and would have been located far enough away from the panels such that ongoing maintenance would have been avoided. The existing meadow grass is such that mowing, if necessary, could be limited to once or twice per year, if at all. Often meadow grass will only grow to a certain height before falling over. The panels are typically placed higher than this. The layout as originally provided and as revised will minimize the need for future vegetation management. 5.2 Evaluate the extent to which selective canopy alteration is feasible to prevent shading of the PVS versus clear-cutting. Neither clear cutting nor selective canopy alteration within the resource areas has been proposed with the original layout or with the revised layout. It will not be necessary since the project is located within the meadow portion of the resource areas only. The original layout proposed to remove an area of trees within the central portion of the site (approximately 30,500 square feet) that was outside of the resource areas and entirely in an upland portion of the site. The revised layout requires that this same area be cleared as well as an additional 34,000 square feet in the southeast corner of the site, also entirely in an upland. 5.3 Evaluate the use of specialized tree clearing equipment from upland locations to reduce wetland alteration for selective tree removal. Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 9 As noted above, there is no cutting or trees, or selective canopy trimming proposed within any resource area. In order to remove the trees in the upland areas described above, equipment will be able to be located entirely within upland areas to complete this work. 5.4 Describe how access roads, wetland crossings and work in the buffer zone will minimize erosion or sedimentation. The access to the project site will be along an existing gravel road that crosses over Hannum Brook to the west of the solar facility. This gravel road currently sheds uncontrolled runoff to Hannum Brook during storm events and results in sedimentation along the length of the roadway through the resource area and buffers. The project proposes to stabilize this area through the installation of grassed drainage swales that will help to control the runoff by introducing vegetated flow paths and stone check dams to reduce velocities. All of this will be done within the existing Park Hill Road right of way. For the solar facility onsite, there are no proposed access roads within any resource areas or buffers. There are no proposed wetland crossings. The project has been designed to minimize disturbances to the existing ground by reducing the limits of grading to only areas adjacent to the roadway, maintaining large areas of existing vegetation in and around the resource areas and providing a perimeter silt fence along the project fence line in all resource areas. The resulting project design results in large uninterrupted vegetated buffers across shallow grades that will prevent sediments from reaching any resource area. 5.5 Demonstrate that ancillary structures related to construction of a solar installation or transmission of power in wetland resource areas are using best design and management practices; if fencing is proposed, the fence shall be at least 6-inches off the ground to provide for wildlife passage for the length of the fence. The proposed project does not feature any ancillary structures in any resource area of buffer zone. The perimeter chain link fence will be installed with a 6-inch gap at the bottom of the fence to allow wildlife movement back and forth through the fence line. Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 10 5.6 Apply the principles of Environmentally Sensitive Site Design and Low Impact Development Techniques (310 CMR 10.04) in the design and monitoring of stormwater controls both during construction and post-construction. The general principals of Environmentally Sensitive Site Design and Low Impact Development include the minimization of land disturbance, the use of land-based runoff controls located at the source and promotion of natural hydrologic features. The project promotes these goals through the use of elimination of pavement throughout the design, the use of sheet flow vegetated buffers from much of the access drive and the inclusion of small softly graded berms and depressions to collect and slow down runoff prior to releasing it to surrounding stabilized areas. In order to qualify and receive credit for Environmentally Sensitive Site Design, there are several criteria that a project must meet as follows: · The total impervious footprint must be less than 15% of the base lot area. The base lot area does not include Resource Areas protected by the Wetlands Protection Act. With only 3,011 square feet of impervious surface and approximately 13.8 acres of land outside of the natural resource areas, the project easily meets this criterion. · No alteration may occur in coastal wetland resource areas other than Land Subject to Coastal Storm Flowage. The project does not alter any land in any coastal resource areas. This criterion is clearly met. · No alteration may occur in BVW and IVW. The project does not propose any alteration in any BVW or IVW. This criterion is clearly met. · A minimum of 25% of the site must be protected as a natural conservation area. The natural conservation area must not include natural resource areas. The project would not meet this criterion for two reasons; there is not enough upland area remaining on the parcel after the ANR subdivision and land donation to the City of Northampton to meet this area requirement, and the project proponent will not be placing an EEA Conservation Restriction on portions of the property. This criterion cannot be met. Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 11 · Stream buffers must be incorporated into the design of any areas adjacent to perennial and intermittent streams on the site. This includes no work within 50 feet of the bank. The proposed project does not propose any work within 100 feet of the bank. This criterion is clearly met. · The amount of impervious surface shall not exceed 40% of the area of the buffer zone between 50 and 100 feet from any resource area, or the amount of existing impervious surface, whichever is greater. This project proposes no impervious surfaces within the buffer zone. This criterion is clearly met. · No work may be proposed within a buffer zone that: o Borders on an Outstanding Resource Water, o Contains NHESP mapped species o Contains slopes greater than 15% prior to any work The project does not contain any work in any of these areas. This criterion is clearly met. · Rooftop runoff must be disconnected. This project will not generate any rooftop runoff. The panels exhibit rooftop-like sheetflow runoff and discharge to pervious ground surfaces below. The ground below the panels are generally flat and the discharge will be directed in a sheetflow manner across vegetated surfaces. This criterion is clearly met. · Qualifying pervious areas are used to convey runoff from roads and driveways instead of curb and gutter systems. The project makes extensive use of the flat vegetated surfaces on the project site to allow runoff to sheetflow and infiltrate in a natural pattern. This criterion has been met. As the above analysis shows, while the project does not meet all criteria of the Environmentally Sensitive site Design credit, it only misses on a single one. While there will not be a conservation restriction placed on 25% of the upland area, the project proponent will be donating 14.66 acres of land to the City of Northampton that centers on Hannum Brook. 6.0 Mitigate Following all efforts to minimize impacts, the applicant must demonstrate that the mitigation measures are provided that: Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 12 · Assure alterations to wetland resource areas BVW will be mitigated pursuant to the requirements of 310 CMR 10.00 and 314 CMR 9.00 (i.e. the mitigation area corresponds to the areal extent of resource areas altered, including the canopy area of trees and shrubs to be removed or pruned within resource areas); The proposed project does not involve any BVW alteration. · Monitoring plans are designed to evaluate mitigation success; There are no proposed areas of BVW creation or enhancement; therefore, there are no proposed monitoring plans in place for those types of areas. During construction, there will be SWPPP monitoring and reporting at least every two weeks and after every rainfall of ¼ inch or greater. Long term monitoring of the site will be based on the overall stormwater management system and the operation of the facility. · To the extent practicable, native soils are undisturbed, or in the cases where topsoil is removed, a minimum of six inches of native topsoil, or a comparable compost-mulch mix is replaced to facilitate plant growth and adequate vegetation coverage to control stormwater runoff. All native soils and topsoil will be left in place. In areas where trees are to be removed from the upland portions of the site, the existing topsoil will be stockpiled and respreads. In areas in and adjacent to the natural resource locations, existing topsoil will not be removed or disturbed other than for the installation of the fence posts and the support table posts. Alternatives Analysis Northampton Community Solar Project Park Hill Road, Northampton, Massachusetts September 2018 Page 13 · Post-construction tree and shrub maintenance plans related to avoiding future shading of panels are developed; and, The project has been designed around the natural resource areas such that tree and shrub maintenance will not be necessary. Mowing once or twice a year to maintain the meadow in its current conditions will be sufficient to ensure that shading of panels will not occur in the areas of the natural resource locations. · Use of seed mixes and plantings are comprised of species native or naturalized to Massachusetts. It is not expected that any seed mixes will be necessary in the natural resource areas. In the upland areas where trees have been removed and adjacent to the newly graded roadways, the project will utilize a flat pea/red top/perennial ryegrass mix that should minimize ongoing vegetation management. 7.0 Conclusion The proposed project revisions represent the most practicable alternative with the least adverse effect on the interests of the Wetland Protection Act for the development of a ground mounted photovoltaic solar facility on the property. The relocations of panels from the Riverfront Area and 100-foot BVW buffer to the southeast corner of the property reduces the impact to the protected areas by utilizing the maximum amount of upland area for the development of the facility. This represents a 56% decrease in the panel area and a 48% decrease in the fenced in area within the Riverfront Area. The project impacts (all area under the panels) have decrease from 5.5% of the total onsite Riverfront Area to 2.4%. In addition to the Riverfront Area impact reduction, the impact to the 100-foot BVW buffer has been eliminated. There are no panels or appurtenant structures proposed within the 100-foot buffer to the BVW. In several location, the fence line will run just inside the 100-foot BVW buffer.