EPA review letter, 133-135 Greenwich Street

NYC 9/11 Public Portal Document

phase must be less than 20% of the total volume of the waste. National Association of Corrosion Engineers (NACE) Standard TM-01-69 as standardized in SW-846 shall be utilized to evaluate corrosion rate if the suspected corrosive hazardous waste is a liquid."

Edited as noted.

Section 5.4, Page 10:

31. The last paragraph on this page states that painted surfaces to be sampled will be sampled for TCLP lead, cadmium, and chromium. Since painted surfaces may contain other metal components such as arsenic and mercury, and Airtek will be running a TCLP analysis, Airtek needs to include all of the metals in its TCLP analysis to determine if the painted surfaces would cause the material to be classified as a hazardous waste. Revise this section and any other sections of the four parts submitted as part of this abatement and demolition project that mention the sampling of painted surfaces, accordingly.

Section Edited as noted.

Section 6.1. Page 11:

32. It may be inappropriate to state that the WTC dust has been sampled to the degree possible. Dust may also be potentially found in the interstitial spaces, and dust has been seen on windows, window sills, mattresses, the floor, etc. Additionally, since there is a large amount of debris currently covering the floors, in particular at 21-23 Thames Street, it is unknown how much dust may be within that debris and the floor beneath that debris. This section should be re-written to note that fact and if additional sampling of dust is to be conducted, this section should provide specific details on the sampling scheme.

Section Edited.

Section 6.2. Page 11:

33. Discuss the representability of the proposed sampling number. See comment number 20 above. Further, please clarify if Airtek is proposing one composite sample per deconstruction material that will consists of five grab samples.

Section Edited. Airtek is proposing one composite sample per deconstruction material, per building, however site conditions may dictate thatfurther sampling is advisable. The plan allows that the Environmental Consultant may make this determination. Where possible, each floor of the buildings will be represented in the sampling. A minimum of 5 grab samples will be compositedfor each material.

Section 6.0. Page 11:

34. Title of this section should be "Sampling Frequencies and Disposal" since disposal options are also discussed in this section.

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NYC-WTC-000134359