Environmental assessment section on physical resources, 2001

NYC 9/11 Public Portal Document

Particulate matter is emitted into the atmosphere from a variety of sources: industrial facilities, power plants, oil burners, construction work, and similar activities. Diesel- powered vehicles, especially heavy trucks and buses do emit particulates; particulate concentrations may therefore be locally elevated near roadways with high volumes of heavy diesel-powered vehicles. Projects involving construction or demolition may increase the level of air pollutants and may adversel” affect air quality.

Sources of air emissions are subject to emission standards and design requirements based on the location of the proposed sourt j, potential quantity of emissions and types of emissions. Federal, state and local regulations potentially governing the construction of the proposed projects include the following:

• Nat’onal and New York Ambient Air Quality Standards (NAAQS and NYAAQS) • New York State Air Toxic Ennssion Guidelines • Air Conformity (40 CFR Part 93) • New York City Air Pollution Control Code requirements

Environmental Impacts

There may be short-term air impacts during facility (buildings, utilities, bridges, parks, subways and walkways) repair, renovation, replacement, construction, tunneling, and demolition activities. The potential air emission sources during construction and demolition activities could include front-end loaders, trucks, and other predominately diesel-powered construction equipment. Since Lower Manhattan is classified as a severe non-attainment area for ozone and particulate matter, proposed federal actions must show conformity to the State Implementation Plan (SIP) before they can be implemented. The action proposed in this PEA. would need to produce less than the de minimis level of 25 tons per year (TPY) for each of the ozone precursors: NOx and VOCs—to ayoid a conformity determination. For all pollutants, an exceedance of the NAAQS constitutes a significant impact. In addition to the NAAQS, New York City has developed de minimis criteria to assess the significance of impacts on air quality that would result from proposed projects or actions being evaluated by the New York City Environmental Quality Review (CEQR).

Emissions produced during construction would consist of exhaust emissions from construction-related equipment and dust generated during soil disturbing activities. Typical pollutants emitted in the exhaust of construction equipment include CO, NOx, SO2, partier late matter (PM, PMio) and VOCs. Dust general^ during construction may consist of particles primarily larger than PMio; however, some dust ircy ;onsist of particles smaller than PMio- Mobile source emissions associated with traffic are not anticipated to increase during construction. Mobile and stationary sources of air emissions related to the construction period may affect air quality and compliance with the SIP. A Conformity Determination would be required under 40 CFR Part 93.153 if the anticipated air emissions during construction and operation are greater than 25 tons per year.

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