40 CFR §265.256

1. (a)Ignitable or reactive waste must not be placed in a pile unless the waste and pile satisfy all applicable requirements of 40 CFR part 268, and:
   1. (1)Addition of the waste to an existing pile (i) results in the waste or mixture no longer meeting the definition of ignitable or reactive waste under § 261.21 or § 261.23 of this chapter, and (ii) complies with § 265.17(b); or
   2. (2)The waste is managed in such a way that it is protected from any material or conditions which may cause it to ignite or react.
2. (b)[Reserved]