WTC site damage assessment map, Sept 21, 2001

NYC 9/11 Public Portal Document

Environmental Impacts

Implementation of any of the proposed action alternatives at WTC site would result in the construction of buildings, installation of utilities, demolition and repair of existing structures, removal of debris fi-om the collapsed subway system, repair of roadways, and construction of pedestrian walkways and bridges. Collapsed buildings would be demolished and replaced. Short-term impacts on community noise levels during construction/demolition activities would include noise fi-om construction equipment and noise from construction vehicles/delivery vehicles traveling to and from the proposed construction site. Construction-related equipment noise levels generally range from 76 dB for hoist operations and 85 dB for backhoe operations to a maximum of 100 dB for pneumatic hammers. Noise levels related to the proposed construction activities at a given receptor would vary widely, depending on the phase of construction. Some anticipated construction activities would include demolition, street and concrete removal, site clearing, tunneling and excavation, foundation installation, etc. Some increased noise levels would be anticipated to be perceptible to the nearby residential neighborhoods and schools located adjacent to WTC area during the construction period.

To minimize the potential impacts of construction noise to surrounding areas, tunneling, pavement breaking, excavation, demolition, and similar activities would be limited to daylight hours as described by the New York City Noise Code, when occasional loud noises are more tolerable. There would be an avoidance of construction and operating noise levels above those required by the Noise Code (65 dBA Leq daytime and 55 dBA Leq nighttime). In addition, there would be an avoidance of operating noise levels constituting a significant impact under CEQR (noise level increases greater than 3 dBA). Extended disruption of normal activities is not considered likely because projects would be performed on a staggered schedule since project planning and design for individual projects would not be performed concurrently. Since this is the case, there would be relatively short-term noise exposure periods anticipated to impact any one receiver during the various construction periods. No significant impacts related to construction noise would be anticipated as a result of the implementation of the proposed alternatives. After the construction period, operating noise levels would be consistent with pre-project conditions and would not exceed CEQR significance criteria.

3.5 CULTURAL RESOURCES

Historic Structures. The area impacted by the WTC disaster contains numerous historic and architecturally significant buildings (Figure 3-9). The WTC is located in Manhattan’s Financial District. The 1970-77 construction of the WTC post-dates the majority of the buildings in lower Manhattan. These range from early religious structures just east of the WTC including Richard Upjohn’s Trinity Church and St. Paul’s Chapel (the oldest house of worship in Manhattan), to skyscrapers chronicling the development of the building type; historically significant early 20'** century commercial office buildings; American financial icons such as the American Stock Exchange and the New York Stock Exchange; and Federal Hall National Memorial where George Washington was inaugurated into office as the first President of the United States.

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