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With respect to transmission electron microscopy (TEM), what does the term "contiguous portions" mean under AHERA?

Contiguous portions means areas directly adjacent to one another that are part of the same functional space. The intent of 40 CFR part 763.90(i)(6) is to prevent an LEA from artificially dividing up a large project so as to avoid the TEM requirement. For example, a local education agency (LEA) that has a 3,300 square foot gymnasium cannot artificially divide the gym into separate areas, and then conduct separate abatement in each area. These areas are obviously contiguous, thus, TEM is required. However, an abatement job in wing A of a building and an abatement job in a separate, non-contiguous wing are not contiguous portions of material.