Dioxin and dibenzofuran analysis data, Sep 2002

NYC 9/11 Public Portal Document

Final Report 125 Cedar Street, NYC, NY

The acceptable results of the sampling represent conditions found on the dates the samples were collected. Individual analytes specified earlier were again analyzed in accordance with the project specifications utilizing the following analytical procedures:

• Lead, EPA Method SW-846-6010B • PAHs, ASTM-6661-01, EPA Method SW-846-8270C • Dioxin, ASTM-6661-01, EPA Method SW-846-8290 • Mercury, EPA Method SW-846-7471A

SCOPE OF WORK

All work performed was conducted in compliance with general industry practices, applicable relevant and appropriate regulations, including, but not limited to the USEPA, USDOL, NYSDOL, NYSDEC, NYCDEP, NYCDOS, and NYCDOH. The scope of work entailed a thorough cleaning of visible dust accumulations from all surfaces within each apartment unit, except as noted within the Project specifications. Cleaning entailed the use of water to mist material prior to cleaning without generating water accumulations. All waste was subsequently double bagged and appropriately labeled prior to disposal. On occasion, equipment that proved to be difficult to clean via wet wiping techniques (i.e.: electrical equipment, fin tube radiators, appliances, etc.) was cleaned by using low pressure compressed air to dislodge settled dust prior to cleaning.

PRo.IEcr DESCRIPTION

Work Sequence

The following lists the sequence for cleaning of accumulated dust:

■ Mobilized equipment and personnel to job site (ATC and Action). ■ Collected and analyzed background wipe samples (ATC). ■ Posted warning signs to establish regulated work areas (Action). ■ Constructed engineering controls per Contract Documents and current regulations (Action). ■ Performed pre-abatement inspection of Contractor engineering controls (ATC). ■ Collected ambient air samples to monitor airborne fiber levels (ATC). ■ Performed required clean-up of settled dust (Action). ■ Performed oversight of Contractor work practi es (ATC) ■ Performed proper removal and disposal of generated waste from the work areas (Action). ■ Performed visual inspections to ensure no visible debris remaining in work areas (ATC).

ATC Project No. 15.22906.0002 Page 3

NYC-WTC 000107591