Federal Register / Vol. 45, No. 98 / Monday. May 19, 1980 / Rules and Regulations

orrecycled, management practices, environmental emissions that attend use

orrecycling, health and environmental effects resulting from use andrecycling and other specific data are veryuseful.

We-also invite commenters to submit specificproposed standards or suggestions forhow standards might be developed. For example, where wastes might be burned as a supplemental fuel in industrial boilers, proposals on fuel ratios, burning temperatures, emission control requirements and residue disposal requirements would be useful. Obviously, the more specific and constructive the suggestions, the morehelpful they will be in our rulemaking.

C. Section261.3 (Definition of HazardousWaste)

This section is a new provision which does not have a direct counterpart in the proposed regulations. It has been added for purposes ofclarification and in
response to questions raised during the
comment period'concerning waste mixtures and whenhazardous wastes become subject to and cease to be subject to the Subtitle C hazardous
waste management system.

If amaterial is ahazardous waste within the meaning ofthis section it
must be managed in accordance with EPA's Part 262 through 265 standards and itsPart 122 through 124 permitting requirements unless covered by one of the exclusions in those regulations or

one ofthe Part 261 special management provisions (§§ 261.5 and 261.6).

1. Whatis a HazardousWaste? Paragraph (a)of this section defines what a hazardous waste is. It provides that a solid waste is a hazardous waste ifit is not excluded under § 261.4(b) and it either (1) is listed as a hazardous
waste in Subpart D. (2) is a waste mixture containing one or more hazardous wastes listed in SubpartD or (3)exhibits one or more characteristics ofhazardous waste identified in Subpart C. A listed waste or a solid waste mixture containing a listed waste which isgenerated by a particular facility may be excluded under the rulemaking procedures prescribed in §§ 260.20 and 260.22 (see section VIIl.C., below). In that event,it will be considered a hazardous waste only ifit exhibits one

or more of the characteristics.

Except for waste mixtures, all these provisions were contained inEPA's December 18, 1978 proposal (see §§ 250.10 (b) and (d)(2), 250.13 and 250.14). The waste mixtures provision is

a clarification which has been added in
response to inquiries about whether mixtures ofhazardous and nonhazardous wastes would be subject
to Subtitle C requirements. This is a very real issue inreal-world waste management, since many hazardous
wastes are mixed with non-hazardous wastes orother hazardous wastes during storage, treatment, ordisposal.

Although it was not expressly stated in the proposed regulation. EPA intended waste mixtures containing listed hazardous wastes to be considered a hazardous waste and managed accordingly. Without such a rule, generators could evade Subtitle C requirements simply by commingling listed wastes with nonhazardous solid
waste. Most ofthese waste mixtures would not be caught by the Subpart C characteristics because they would contain wastes which were listed for

reasons other than that they exhibit the characteristics (e.g., they contain carcinogens, mutagens or toxic organic materials). Obviously, this would leave

a major loophole in the Subtitle C management system and create inconsistencies in how wastes mustbe managed under that system.

EPArecognizes that designating all waste mixtures containing listed wastes

as hazardous wastes under Subtitle C may create some inequities. For example, this approach may result in

some waste mixtures which contain only very small amounts oflisted hazardous wastes or which commingle waste in a way which renders them nonhazardous (e.g., neutraliiation) having to be managed under Subtitle C. We have tried to address this problem by establishing provisions foramending this paragraph to exclude waste mixtures produced by individual facilities, ifthey can show that the mixture (oreach constituent listed hazardous waste) isnot hazardous, based on the criteria for which the consistuent hazardous wastes were listed. Because this is a rulemaking procedure, itwill, as a practical matter. only be useful forfacilities which routinely mixwastes in relatively constant proportions. With a regulated community potentially numbering in the hundreds ofthousands, we simply do not have the resources toprocess petitions for exempting "one-shot" waste mixtures. Moreover, in most of these one-time cases, it seems likely that the burden ofhaving to manage a waste mixture as a hazardous waste could be easily avoided by carefully segregating hazardous and non-hazardous waste.

We know ofno other effective regulatory mechanism for dealing with waste mixtures containing listed hazardous wastes. Because the potential combinations oflisted wastes and other wastes are infinite, we have been unable to devise any workable, broadly. applicable formula which would distinguish between those waste mixtures which are and are not hazardous. Ifany members ofthe public have suggestions for other approaches,

we would appreciate having them brought to our attention forfuture rulemaking.

Waste mixtures containing only
wastes which meet the characteristics

are treatedjust like any other solid wastei.e., they willbe considered hazardous only ifthey exhibit the characteristics. EPA recognizes that this may not be an altogether satisfactory regulatory approach. While it would no doubt encourage some desirable mixing ofwastes, it would also allow some wastes (principallywastes caught by EPA's extraction procedure) to escape regulation merely bybeing mixed with otherwastes orother materials.We know ofno solution to this problem which does not create major inconsistencies in the way wastes are determined to be hazardous under Subpart C ofthisregulation. Again, if the public has suggestions forother ways ofdealing with this issue,we would like toreceive them.

2. WhenDoesa WasteBecome a HazardousWaste?Paragraph (b) provides three simple rulesfor determining when a solid waste becomes a hazardous waste and therefore mustbe managed under Subtitle C.Ithas been provided in response tocomment requesting clarification on this issue.

Paragraph (b) states that a solid waste which is a hazardous waste because itis listed in Subpart D mustbegin to be managed as a hazardous wastewhen it first meets the Subpart D listing description. Most ofthehazardous wastes listedin §§ 261.31 and 261.32 of Subpart D are process residues, emission control dusts, orwastewater treatment sludges, and thepoint in time when they are created is generally welldefined. For those used materials which

are listed as hazardous wastes inthose sections or §261.33 (e.g., spent solvents), the point at which they meetthe listing description is somewhat less welldefined, butgenerally occurs when their intended usehas ceased, and theybegin
to be accumulated or stored for disposal,

re-use or reclamation.

In the case of awaste mixture containing alistedhazardous waste, paragraph (b)requires that the waste mixture be managed as a hazardous waste as soon as the listed waste is added to it. The listed waste, ofcourse, must be handled as a hazardous waste prior to thattime.

Finally, paragraph (b)provides that a solid waste is a hazardous waste 3309J5F