A. INTRODUCTION B. LAND USE, ZONING, AND PUBLIC POLICY C. SOCIAL CONDITIONS

Transcription

1 Chapter 18: Mitigation Measures A. INTRODUCTION Chapters 3 through 17 of this document examine the potential for significant adverse impacts from the project alternatives. For any such impacts identified, mitigation measures are described in detail in those chapters. These measures are summarized in this chapter of the MIS/DEIS. B. LAND USE, ZONING, AND PUBLIC POLICY The new East Side subway could require acquisition of private property for use as a construction shaft site and staging area. If a privately owned site is selected, mitigation would be in the form of financial compensation to affected property owners. Specific mitigation measures (discussed later in this chapter) are proposed to ameliorate, to the extent possible, the traffic congestion, noise and vibration, and dust associated with construction of the new subway under Build Alternative 1. The mitigation measures associated with the new subway are described above. Similar to the new subway, the specific mitigation measures discussed later in this chapter for displacement as well as traffic, air quality, noise, and vibration would mitigate to the extent possible the disruptions associated with construction of the LRT under Build Alternative 2. C. SOCIAL CONDITIONS During construction of the cut-and-cover portions of the new subway, as well as during construction activities at the subway construction shaft site, dust suppression and noise and vibration mitigation measures would be employed to minimize these construction-related nuisances to surrounding community facilities. In addition, as discussed under Transportation, maintenance and protection of traffic plans would be implemented to minimize traffic disruptions to the extent possible and to ensure that pedestrian and vehicular access remains available to nearby community facilities at all times. In addition to the mitigation measures for the new subway, discussed above, similar dust suppression and noise and vibration mitigation measures would be implemented during construction of the LRT and maintenance and protection of traffic plans would be employed to minimize 18-1

2 Manhattan East Side Transit Alternatives MIS/DEIS traffic disruptions and maintain pedestrian and vehicular access to nearby community facilities at all times. The LRT component of Build Alternative 2 would not include shelters or structures near Straus Square, Seward Park, or Union Square Park, thereby avoiding any impacts to those parks. D. ECONOMIC CONDITIONS For any properties that would have to be acquired for the new subway including private properties used for a construction shaft site and any properties required for easements to allow new station entrances owners would be compensated at fair market value and relocation benefits would be provided for displaced businesses. For any necessary relocation, relocation assistance offices would be established to facilitate the appropriate activities. Relocation assistance would include the following guarantees:! As part of the preparation procedure during the acquisition stage, all site occupants would be personally interviewed to determine their specific relocation needs.! The acquisition and relocation assistance programs would be conducted in accordance with the requirements and standards of the federal Uniform Relocation Assistance and Real Property Acquisition Policies Act of 1970 as amended. This Act governs property acquisitions whenever they are carried out by the federal government or when property acquisition involves the use of federal funds.! All site occupants would be furnished a copy of New York State s informational booklet and would be fully informed of all benefits to which they may be entitled.! No site occupant would be required to move from his or her property without at least 90 days notice.! The relocation program would be carried out in an orderly, humane, and timely fashion.! Relocation assistance would be offered to all being relocated without discrimination. Significant economic impacts may occur for some marginal businesses in areas near cut-andcover construction work associated with the new subway. Mitigation for these impacts would be in the form of financial compensation to affected businesses. The mitigation measures associated with the new subway are described above. Relocation benefits and/or financial compensation would also be provided for businesses that are indirectly displaced as a result of construction activities associated with the LRT. This is most likely to occur for businesses along Canal Street near the construction work, but could occur in other locations as well. Build Alternative 2 could result in significant adverse impacts to nearby businesses along Canal Street during operation. Mitigation for these impacts would be in the form of financial compensation to affected businesses. 18-2

3 Chapter 18: Mitigation Measures E. VISUAL AND AESTHETIC CONSIDERATIONS During construction, the construction staging site required for the new subway would be potentially incongruous with the surrounding neighborhood, no matter which site is selected. This site would be surrounded by a barrier, reducing its visibility to the surrounding neighborhood. Under Build Alternative 1, entrances to the proposed new East Side subway extension would be sited within buildings, to the extent possible, to minimize effects to the visual character of the study area. Overall, the new subway would not result in significant adverse impacts to visual character. In addition to the mitigation discussed above for the new subway, Build Alternative 2 would also incorporate mitigation measures related to the new LRT. Under Build Alternative 2, design elements to minimize visual intrusions (e.g, shelters at LRT stops, overhead wires) would be incorporated into this alternative to help mitigate the effects of these components. The stations, where possible, would be adjacent to the sidewalk at either side of the street, and designed to function as extensions of the curb line rather than as raised or freestanding platforms. Similar to city bus stops, they would have a minimum of street equipment and furniture, and a maximum amount of transparency. Where island platforms are required, they would be as narrow as possible and designed like the traffic islands of Broadway and Park Avenue, with a minimum number of visual obstructions (railings, light and power poles) and a maximum number of visual amenities (landscaping, seating etc.). To address potential concerns about visual impacts of the LRT on Union Square Park as well as Straus Square and Seward Park, the LRT stops there would not include any shelter or other street furniture. It would also be possible to terminate LRT service one block east of Union Square Park so that light rail vehicles do not stop at Union Square Park at all. This mitigation option would make connections to the subway station beneath the park slightly more difficult for riders. Another option to avoid a terminus at Union Square would be to continue LRT service to the west. This is discussed below under section L, Other Issues. F. HISTORIC RESOURCES The studies undertaken for this MIS/DEIS identified potential significant adverse impacts to historic resources related to both Build Alternative 1 and Build Alternative 2. As project plans proceed with selection of a preferred alternative and preparation of a Final Environmental Impact Statement (FEIS), ongoing consultation will be undertaken with the State Historic Preservation Office at the New York State Office of Parks, Recreation and Historic Preservation (SHPO) and with the federal Advisory Council on Historic Preservation. This ongoing consultation is mandated by Section 106 of the National Historic Preservation Act of

4 Manhattan East Side Transit Alternatives MIS/DEIS With the new East Side subway extension proposed as part of Build Alternatives 1, two buildings near the northeast corner of 125th Street and Lexington Avenue that were determined eligible for the State and National Registers of Historic Places would require underpinning because the subway would pass beneath them and would be relatively shallow. For these buildings, a construction protection plan would be prepared by qualified engineers and implemented by qualified personnel, including an independent engineer authorized to stop work if damage is found at the buildings. This plan would be submitted to SHPO for review and approval prior to the start of construction. At all other locations, appropriate care would also be taken to ensure that the construction not result in any structural impacts to buildings. In addition, one of the possible shaft and staging sites being considered the site located between 65th and 66th Streets contains a potential historic resource. If this resource is determined eligible for Register listing or is found to merit NYCL status, another site could be selected or appropriate mitigation could be developed through consultation with SHPO in order to avoid an adverse effect. For the shaft and staging site that is selected, a construction protection plan for any nearby resources would be prepared by qualified engineers and implemented by qualified personnel. This plan would be submitted to SHPO for review and approval prior to the start of construction. As project plans proceed after selection of a preferred alternative, to avoid potential contextual impacts on historic resources from operation of the proposed project stemming from the addition of new elements such as signs, stairways, vents, and other features related to the new subway or light rail system, project components would be carefully designed, and proposed plans would be submitted to SHPO for review during the ongoing consultation process. Proposed plans would be submitted to SHPO for review during the ongoing consultation process for this alternative. In addition, as project plans are finalized, additional locations of cut and cover construction or areas that could be affected by additional project elements not previously considered would be surveyed for potential historic impacts in consultation with SHPO and LPC. In summary, as project plans proceed with selection of a preferred alternative and preparation of a Final Environmental Impact Statement, the ongoing consultation process with SHPO and the Advisory Council on Historic Preservation will continue, and a Memorandum of Agreement and/or a Programmatic Agreement will be executed by New York City Transit, the Metropolitan Transportation Authority, the Federal Transit Administration, SHPO, and, if necessary, the Advisory Council on Historic Preservation, outlining the process and measures to be undertaken to avoid any adverse impacts to historic resources. As noted above for Build Alternative 1, above, as project plans proceed with selection of a preferred alternative and preparation of a Final Environmental Impact Statement, the ongoing consultation process with SHPO and the Advisory Council on Historic Preservation will continue. The steps described above for that process would also occur for Build Alternative 2, if it (or its LRT component) is included in the preferred alternative. In addition to the concerns noted above for the East Side subway extension, Build Alternative 2 would have the following mitigation issues, raised by its LRT, related to historic resources. 18-4

5 Chapter 18: Mitigation Measures Construction of the LRT s below-grade maintenance and storage yard would require underpinning of the Essex Street Market building, which has been determined eligible for the State and National Registers of Historic Places. For this building,a construction protection plan would be prepared by qualified engineers, reviewed and approved by SHPO, and implemented by qualified personnel, including an independent engineer authorized to stop work if damage is found at the buildings. At all other locations, appropriate care would also be taken to ensure that the construction not result in any structural impacts to buildings. As project plans proceed after selection of a preferred alternative, to avoid potential contextual impacts on historic resources from operation of the project stemming from the addition of new project elements, project components would be carefully designed, and proposed plans would be submitted to SHPO for review during the ongoing consultation process. For example, efforts would be made to design light rail components, such as platform areas, that are compatible with adjacent historic resources. Proposed plans would be submitted to SHPO for review during the ongoing consultation process for this alternative. In addition, as project plans are finalized, additional areas that could be affected by additional project elements not previously considered would be surveyed for potential historic impacts in consultation with SHPO and LPC. G. ARCHAEOLOGICAL RESOURCES BUILD ALTERNATIVES 1 AND 2 Studies undertaken for this MIS/DEIS identified that significant adverse impacts on archaeological resources could result from both the new subway (Build Alternatives 1 and 2) and the new LRT (Build Alternative 2). As described above, as project plans proceed with selection of a preferred alternative and preparation of a Final Environmental Impact Statement (FEIS), ongoing consultation will be undertaken with the State Historic Preservation Office at the New York State Office of Parks, Recreation and Historic Preservation and with the federal Advisory Council on Historic Preservation. As part of the consultation process, additional work will be performed where the potential for significant impacts to archaeological resources has been identified for the project components selected as the locally preferred alternative. For the alternative selected as locally preferred, further archaeological research in the form of a full Stage 1A investigation will be undertaken for all areas considered potentially sensitive for archaeological resources. SHPO and LPC (in correspondence dated December 10, 1998 and October 20, 1998, respectively) have concurred that a Stage 1A investigation is appropriate for these areas. This analysis will be completed prior to the FEIS. In addition, for the selected alternative, areas of potential disturbance that have not yet been specifically located (such as areas to be affected by ventilation shafts for the new subway or by electrical substations for the LRT) will be defined. Archaeological research in the form of a Stage 1A report will then be performed for those areas to determine their potential sensitivity as well as potential significance. Should the location or the depth of disturbance change from that in this study, further research into the potential for archaeological resources in the selected locations will be conducted to avoid significant impacts on archaeological resources. At any locations identified as potentially significant, if feasible, project elements would be relocated to avoid the impact. Otherwise, appropriate mitigation measures (such as archaeological testing or excavation and data recovery) will be developed through ongoing consultation with 18-5

6 Manhattan East Side Transit Alternatives MIS/DEIS SHPO so that no significant adverse impact would occur. A Memorandum of Agreement and/or a Programmatic Agreement will be executed by New York City Transit, the Metropolitan Transportation Authority, the Federal Transit Administration, the SHPO, and, if necessary, the Advisory Council on Historic Preservation, outlining the process and measures to be undertaken to avoid any significant adverse impacts to archaeological resources. H. TRANSPORTATION TRAFFIC TSM ALTERNATIVE During construction of the TSM Alternative, maintenance and protection of traffic plans would be implemented to preserve pedestrian, vehicular traffic, and bicycle flows through the construction areas. In some locations, bus stops would be temporarily relocated one or two blocks away until construction in that area is complete. Once operational, the TSM Alternative would result in some significant impacts to vehicular traffic, primarily along the First and Second Avenue routes of the semi-exclusive bus lanes, and to a lesser extent at some intersections of parallel north-south avenues with major crosstown streets. Detailed traffic mitigation analyses were undertaken for all locations where significant impacts or significant worsenings were projected, with the following conclusions:! Signal phasing and/or timing modifications would be sufficient to mitigate significant impacts at all of the impacted locations with the few exceptions listed below.! 23rd Street and Park Avenue: Extend current No Stopping parking regulations over the entire northbound Park Avenue curb lane, south to 22nd Street, and designate the curb lane for right turns only.! 59th Street and First Avenue: Reduction of the bus lane treatment to a one-lane operation in the vicinity of this location. Two bus lanes cannot be provided due to the number of traffic lanes needed to accommodate right-turning volumes toward the Queensboro Bridge and general northbound through traffic.! 59th-62nd Street and Second Avenue: Due to the extremely high level of congestion that prevails at this major entry point to the Manhattan Central Business District, a two-lane bus treatment cannot be accommodated with standard traffic engineering improvements. Options include 1) discontinue the bus lanes at 59th Street and, in all likelihood, several blocks north; 2) implement a one-lane bus lane treatment as well as a highly intensive enforcement program to eliminate all gridlock at this location (this, like similar existing traffic enforcement measures, would be the responsibility of the Police Department and the city s Department of Transportation); 3) consider building an underpass for through traffic to bypass this highly congested section of Second Avenue. All of these measures would need to extend at least as far north as 62nd Street, if not as far north as 64th-66th Streets since the bridge-induced backup often persists that far uptown. Discontinuing the bus lane treatment would offer no transit relief in this section, and therefore should be viewed only as a last resort. Reducing the bus lane treatment to one lane would not offer the same level of transit benefit as would a two-lane New York Bus Lane 18-6

7 Chapter 18: Mitigation Measures and would require a far more intensive deployment of enforcement agents, but could mitigate traffic impacts associated with the bus lane treatment. Construction of an underpass, similar to the underpasses existing along First Avenue at 42nd Street and along Park Avenue near 34th Street, could afford measurable traffic relief and bus travel time benefits, but its feasibility in light of possible infrastructure issues would need to be addressed.! 62nd-64th Street and Second Avenue: Reduction of the bus lane treatment to a one-lane operation.! 96th Street and First Avenue: Deployment of one or more enforcement agents during the PM peak period to avoid gridlocked conditions. The enforcement agents would be used to ensure that green signal time that is currently unused by traffic because of the gridlocked conditions can be made usable in the future. This is a location at which enforcement agents have historically been deployed. Successful operation of the bus lane treatment would require consistent deployment of this mitigation in the PM peak period. For the new subway under Build Alternative 1, construction work that affects existing subway service would be carefully timed to minimize necessary track outages to the extent possible and to limit those disruptions to subway service to nights and weekends. Maintenance and protection of traffic plans would be implemented to preserve pedestrian, vehicular traffic, and bicycle flows through areas affected by cut-and-cover construction work for subway stations and the area around the access shaft site. Similar to Build Alternative 1, for construction of the new subway and LRT under Build Alternative 2, maintenance and protection of traffic plans would be implemented to preserve pedestrian, vehicular traffic, and bicycle flows through the construction areas. In some locations along the LRT route, bus stops would be temporarily relocated one or two blocks away until construction in the area is complete. Construction work that affects existing subway service at Chambers Street would be carefully timed to minimize the necessary track outages to the extent possible. Once the LRT is operational, significant impacts to vehicular traffic are predicted because of the LRT component of Build Alternative 2 at a series of locations along the alignment (primarily along Water Street/Pearl Street and along 14th Street) and at several locations due to the diversion of traffic from the route of the LRT to other parallel routes (primarily Houston Street and 23rd Street). Detailed traffic analyses were conducted at all locations where significant impacts were identified. These studies concluded that signal phasing and/or timing modifications would be sufficient to mitigate significant impacts at most of the impacted locations. For several key segments along the LRT alignment, curb parking/standing/loading would need to be prohibited to provide sufficient capacity to accommodate traffic volume demands with the required amount of traffic capacity. This is particularly necessary along Water and Pearl Streets in Lower Manhattan and along 14th Street. 18-7

8 Manhattan East Side Transit Alternatives MIS/DEIS PARKING TSM ALTERNATIVE With the TSM Alternative, the New York Bus Lanes would add a significant amount of curb parking/delivery/loading spaces within the overall study area in the AM and PM peak periods, but would reduce such spaces overall during the midday period and within specific segments of the study area during the AM and PM peaks. For several segments of the area, the net reduction in curb spaces is relatively small. For other areas, such losses are fairly significant but may be considered partially or fully offset by net gains during other periods of the day (local businesses, for example, may be able to schedule deliveries for time periods when curb space would become available under the New York Bus Lanes plan). Mitigation does not appear to be necessary for this alternative. With Build Alternative 2, the LRT system would create a net reduction of about 442 curb spaces areawide along the alignment. On some segments where a large number of spaces would be lost, parking lots nearby might be able to accommodate the loss of on-street metered spaces. For other segments, it may be beneficial to create new alternative spaces. This could include, for example, the approximately 175 spaces lost along Columbia Street and Avenue D. Mitigation, in terms of replacing lost spaces with new off-street parking lots will be examined in the Final EIS, if the LRT is part of the selected locally preferred alternative. The traffic and parking studies conducted for the TSM Alternative and the LRT component of Build Alternative 2 indicate that there are trade-offs between traffic level of service needs and local area parking needs. It is quite possible that future refinements of either of these alternatives, should one of them be selected as the locally preferred alternative, would reallocate a curb lane from its initial assumption as a traffic lane to a new designation as a curb parking/delivery lane if the need for the latter proves to be more significant than the former. It is also possible that modest sidewalk width reductions could preserve curb parking lanes along several blocks of the LRT alignment. I. AIR QUALITY To minimize air quality impacts during construction of any of the project alternatives, excavation and construction would be conducted with care and all appropriate fugitive dust control measures including watering of exposed areas and dust covers for trucks would be employed to minimize effects to nearby people or buildings. The traffic maintenance and protection plans would be designed to minimize, to the extent possible, the vehicular congestion and associated air quality problems. 18-8

9 Chapter 18: Mitigation Measures J. NOISE AND VIBRATION NOISE TSM ALTERNATIVE Once operational, the TSM Alternative would result in significant noise impacts according to FTA criteria at noise receptors on the Lower East Side, because of the relocation and reallocation of existing M15 and M22 bus service. There are no feasible mitigation measures for this impact. During construction, noise from activities at the access shaft and staging site would result in significant noise impacts at surrounding receptors. A barrier would be constructed around the site, but this would reduce noise levels only at street level. Similarly, plywood barriers would be constructed around only open excavation areas, but this would only partially reduce noise levels at these sites. To reduce the noise associated with blasting at cut and cover excavation sites, the contractor would be required to use modern blasting techniques such as timed multiple charges, blast mats, etc. which tend to lessen the severity of blasting noise levels. Where pile driving is required (at cut and cover excavation sites), if geological conditions are appropriate, vibratory rather than impact pile drivers would be used to lessen the noise levels produced from this activity. The analysis of noise from operation of the new subway assumes that the ventilation shafts and station entrances would be designed to attenuate noise levels in the underground tunnels by approximately 20 dba at the surface ventilation openings and surface station entrances. With these measures, no significant noise impacts would occur. The operation of new subway trains at the 36th-38th Street Yard in Brooklyn could result in significant noise impacts at nearby residences. Additional analysis of these potential noise impacts will be conducted for the FEIS. Possible mitigation measures would include construction of noise barriers at the edge of the yard. In addition to the mitigation measures for the new subway, described above, the LRT would also result in potential noise impacts associated with construction of cut and cover portions of the alignment. Mitigation measures would be the same as those described above for the subway. VIBRATION TSM ALTERNATIVE To avoid any architectural damage (e.g., cracked plaster) to extremely fragile buildings within 80 feet of the pavement-breaking operations, deep saw cuts would be made between areas of pavement breaking and the sidewalk areas in front of buildings. Deep saw cuts would create discontinuities in the soil nearest the pavement breaking, minimizing the transmission of vibrations from pavement-breaking operations to the foundations of nearby buildings. With this technique, 18-9

10 Manhattan East Side Transit Alternatives MIS/DEIS ground-borne vibration levels should be below 0.12 inches per second at the foundations of most buildings, and no damage is anticipated. Mitigation During Construction Mitigation measures for pavement-breaking operations are described above for the TSM Alternative. To limit the potential vibrations associated with pile driving, vibratory pile drivers would be used where possible, and earthmoving as well as pile driving operations would be scheduled so as not to occur at the same time period. To protect nearby structures during blasting, blasts would be contained through the use of rubber or steel cable blasting mats, earthen cover, or by utilization of the original overburden line drilling would be used to reduce ground vibration. Modern blasting techniques such as timed multiple charges, which lessen the severity of vibration levels, would be implemented. Vibration levels would be monitored in the foundations of nearby buildings (within 365 feet of immediate blasting operations ) during all blasting activities. Blasting activities resulting in peak particle vibration levels in excess of 0.12 inches per second as measured in the foundations of nearby structures would be immediately stopped until further precautionary measures are taken to reduce blasting-related vibration impacts. Work would not begin again until the steps proposed to stabilize and/or prevent further damage to the designated buildings were approved. In addition, the contractor would carry insurance to cover the expense of restoration caused by any damage that might occur despite this precaution. Also, special measures set forth by the New York City Landmarks Preservation Commission would be followed to protect historic resources from increased vibration levels from all construction activities. At any construction locations where historic resources and particularly older fragile buildings are located within specific distance criteria (365 feet for blasting, 135 feet for impact pile driving, 85 feet for vibratory pile driving, 80 feet for pavement breaking, 20 feet for bulldozing, 18 feet for heavy truck traffic, and 11 feet for use of jackhammers), construction contractors would be required to implement special vibration protection measures. These measures, to be included as part of the construction protection program for historic resources (discussed above), would likely include an inspection of the current foundation and structural condition of any historic buildings, use of a monitoring program to measure vertical and lateral movement and vibration to the historic structures during nearby construction activities; and issuance of stop work orders, as required, to prevent damage to the structures, based on any vibration levels that exceed 0.12 inches per second in lateral or vertical direction. Mitigation Measures During Operation To prevent significant vibration impacts during operation of the new subway at each new station and at three track crossover locations for the new subway proposed under Build Alternative 1, a 10 db reduction in vibration levels would be required. This could be achieved through the use of such options as ballast mats or resiliently supported ties

11 Chapter 18: Mitigation Measures Mitigation measures for the new subway are described above under Build Alternative 1. Mitigation measures for potential vibration impacts during construction of the LRT would be the same as those described above for the new subway. In addition, to prevent significant vibration impacts associated with the LRT under Build Alternative 2, high resilience fasteners would be used at crossover locations. K. HAZARDOUS MATERIALS BUILD ALTERNATIVES 1 AND 2 Both Build Alternatives 1 and 2 have the potential to expose hazardous materials in the soil and groundwater during construction activities. To eliminate any potential health concerns related to possible hazardous materials, prior to the commencement of construction, a thorough investigation would be undertaken for each location where cut-and-cover construction techniques would be utilized. This investigation would include on-site testing and reviews of the files of agencies that regulate the use, storage, disposal, or transport of hazardous materials, as well as regulatory records related to underground storage tanks, to identify more accurately the locations and extent of potential contamination. A thorough investigation for underground tanks would be made for each segment of the construction during preliminary engineering, and site-specific remediation plans would be made in accordance with all applicable federal, state, and local regulations. Based on this investigation, a site-specific Health and Safety Plan would be developed for each phase of the construction to limit the potential for worker and public contact with any contamination found in either the soil or groundwater. The provisions of the Health and Safety Plan would be mandatory for the contractors and subcontractors engaged in any on-site construction activities that have the potential to expose their personnel to the existing soils on the site. In addition, all on-site personnel would be required to follow all applicable local, state, and OSHA construction codes and regulations. During construction, any unusual conditions such as odors or discoloration of the soil that may indicate unexpected contamination would be specifically checked for at all times. Any contaminated materials encountered during construction would be handled, stored, and disposed of in accordance with all applicable federal, state, and local regulations and in compliance with the site-specific Health and Safety Plan. L. OTHER ISSUES: POSSIBLE WESTWARD EXTENSION OF LRT UNDER As described above, under Build Alternative 2, one of the possible mitigation measures to avoid the visual changes associated with an LRT terminus at Union Square Park would be to continue the light rail service westward past the park. Continuing the LRT westward across 14th Street to a terminus at or near Route 9A and the Hudson River would also improve the transit service provided, and provide access to the new Hudson River Park being developed along the riverfront. It would also eliminate the need for the M14 bus altogether. Riders who wished to travel the length of 14th Street could enjoy a one-seat ride, which otherwise would not be possible with the new LRT service

12 Manhattan East Side Transit Alternatives MIS/DEIS In most environmental areas, new LRT service would raise the same issues on 14th Street west of the park as in other parts of its route. As in Lower Manhattan and the Lower East Side, the new tracks in existing streets and the presence of overhead wires along the route would change the appearance of the area, but this change would not be considered significant given the developed and urban context of the project corridor. However, continuation of the LRT along 14th Street west of Union Square Park raises the potential for a number of significant adverse impacts, as described below. If an extension of the LRT is included in the preferred alternative, these impacts and possible mitigation will be detailed in the Final EIS. HISTORIC RESOURCES Using the same approach as for the rest of the LRT route, the area of potential effect along the light rail transit extension would include the buildings fronting onto 14th Street. Within this area are a number of known historic resources (these include a portion of the Greenwich Village Historic District as well as the New York County National Bank and New York Savings Bank, both at Eighth Avenue, and the Andrew Norwood House at 241 West 14th Street). Potential resources may also be located in this area. However, the LRT is unlikely to result in significant impacts on these resources, since all the buildings in the APE are within a densely developed, dynamic, and highly urbanized context and since 14th Street was historically the location of both trolley lines and horsecar lines. ARCHAEOLOGICAL RESOURCES Similar to the rest of 14th Street, it is highly likely that construction of the subway beneath 14th Street in combination with the extensive utility work there has disturbed or destroyed any potential archaeological resources that were once located there. It is possible, however, that some undisturbed areas may remain in some part of the LRT extension route. If so, further research would be performed (as described earlier for other potential archaeological resources to be affected by the project) to identify any resources and avoid or mitigate any impacts. TRANSPORTATION While the overall effect of extending LRT service westward would be to improve transportation services, because it would occupy a portion of heavily traveled 14th Street, an LRT extension west of Union Square Park has the potential to cause significant traffic impacts at various locations, both along 14th Street and along other streets as a result of diversions from 14th Street. These impacts could occur both during construction and operation of the LRT extension. In addition, the new LRT would also require elimination of some on-street parking on 14th Street. NOISE AND VIBRATION As with the other LRT segment, vibration mitigation would be required to eliminate the potential for impacts at any crossover tracks included in the westward extension of the LRT. HAZARDOUS MATERIALS The extension of the LRT, like the rest of the route, would introduce potential risk to workers, pedestrians, and residents from surface construction activities. To eliminate any potential con

13 Chapter 18: Mitigation Measures cerns, prior to construction, a thorough investigation would be undertaken and a site-specific Health and Safety Plan would be developed