Section 60. Categories

Article 2. Categories of Facilities

For the purposes of this chapter, hazardous waste facilities are broken down into five basic categories: (i) containerized or enclosed storage; (ii) closed treatment process with spill containment; (iii) open treatment process with spill containment; (iv) any above ground treatment with no spill containment; and (v) disposal without complete treatment and all other treatment/disposal methods.

A. Category I—Containerized or enclosed storage.

1. Description. A facility which is designed to store waste in above ground tanks, or portable containers as defined in 40 CFR Part 264 Subparts I and J, and § 10.1-1433 of the Code of Virginia provided that the area where the waste is stored meets at least the "containment" requirements specified in 40 CFR Part 264 Subpart I. In general, this section requires that the base under the storage area be free of cracks or gaps and is sufficiently impervious to contain leaks, spills or accumulated precipitation. It also must have sufficient containment capability to hold 10% of the volume of the containers stored, or the whole volume of the largest container, whichever is greater, and must be able to contain any run-off which might be involved. Containment requirements will be considered on a case-by-case basis. For the purpose of siting criteria, a facility which uses tanks must also conform to these requirements in order to be classified in Category I.

Examples include but are not limited to such facilities as:

a. A warehouse for storing 55 gallon drums.

b. A tank to store materials for loading into an ocean-going incineration vessel.

c. A storage tank associated with a land based treatment facility.

2. Consequences of loss of control. Because of the fairly simple operations involved and the extensive spill containment requirements, the consequences of loss control, for the purposes of siting, would be:

—Fire or explosion, or both.

B. Category II—Closed treatment process—with spill containment.

1. Description. A facility which is designed to treat hazardous waste by any method which did not involve venting, evaporating or exhausting potentially toxic concentrations of materials to the atmosphere, as measured at the active portion of the facility, under any normal or abnormal operating conditions. This could include chemical processes, such as acid neutralization, where the hazardous constituents in the waste are converted to nonhazardous materials or are precipitated out for disposal as a solid. It might also involve a process which separates the liquid portion of the waste from the solids, such as a centrifuging, mechanical or carbon filtration, settling or flotation, encapsulation, absorption, etc. If improper mixing or misoperation of the unit could cause a pressure build-up which could vent potentially toxic concentration of material to the atmosphere through a relief valve or similar device, this unit would not qualify as Category II. Systems which vent internally into a flash tank or similar device, however, would not necessitate a Category III classification since in that situation they would not be venting into the atmosphere. Furthermore, in order to qualify for this category, all processes must be in an area that meets the "containment" requirements specified for Category I such that a leak or rupture anywhere in the system would be contained for controlled disposition in accordance with all appropriate regulations.

An example is, but not limited to:

—Treatment in tanks.

2. Consequences of loss of control. These types of facilities are similar to those in Category I with respect to the health or environmental impact of loss of control except that there are likely to be more operations involving handling, movement, mixing, pumping or otherwise processing the waste. This, combined with the probability that more complex systems, different kinds of equipment, piping and controls are involved in Category II, makes the probability of loss of control somewhat greater than in Category I. However, because of the extensive spill containment requirements necessary to be classified as Category II, the consequences of loss of control are minimized. For the purpose of siting they would be:

—Fire or explosion, or both.

C. Category III—Open treatment process—with spill containment.

1. Description. A facility which is designed to treat waste by heating or burning, distillation, or any other reaction of process which involves a need to vent or exhaust any material to the atmosphere under normal operating conditions and which could, with a reasonable degree of probability, if misoperated or through malfunction or any loss of control, discharge a potentially toxic concentration of material, as measured at the active portion of the facility.

Facilities which have the potential for discharging only steam, air, nitrogen, or other nontoxic materials could be classified as Category I or II, providing they meet all other requirements for those categories. Heated storage tanks or rail cars which use steam in an outer shell or coils, for example, could be classified as Category I, even if it was periodically necessary to vent steam to the atmosphere.

In order to qualify for Category III, all tanks, containers or ancillary storage devices associated with processes must be in an area which meets the "containment" requirements specified for Categories I and II above.

An example is, but not limited to:

—Incineration.

2. Consequences of loss of control. The major difference between processes in this category and those in Category II is the possibility of (i) air quality degradation of sufficient magnitude to have the potential for causing health hazards, or (ii) environmental problems outside the facility from uncontrolled process discharges. Because it is so unlikely that any such discharge could be concentrated enough or last long enough to cause significant surface or groundwater degradation, this is not considered a consequence which would occur from loss of control. If, for some reason, there was a reasonable possibility that an airborne discharge from a facility could cause off-site surface or groundwater degradation, the facility would have to be classified in Category IV or V.

For the purposes of siting, the consequences of loss of control in Category III are:

a. Fire or explosion, or both.

b. Air quality degradation from process exhaust or venting as a result of loss of control.

D. Category IV—Above ground treatment—no spill containment.

1. Description. A facility which is designed to treat or store hazardous waste by any process or method which, with a reasonable degree of probability, through misoperation or any loss of control, could cause off-site surface or groundwater degradation.

These facilities need not meet the "containment" requirements specified for facilities in the three categories above in order to be classified in this category.

"Above ground" in this category means that the hazardous waste is all contained at or above the level of the ground where it is located. This qualification is based on providing a reasonable opportunity to see or become aware of a leak without depending on groundwater analysis. For example, this category could include a metal tank which rested directly on a cement pad (i.e., without support legs) even though part or all of the cement pad was actually below the ground, so long as the bottom of the tank was above ground level. If the bottom of the tank were below ground level resting directly on a manmade or earthen support such that the bottom of the tank could not be routinely inspected externally for leaks, the unit would qualify for Category V. In this latter example, if the tank were in a pit but was elevated from the base of the pit in such a manner as to allow routine inspection of the bottom to detect leaks it could be classified in Category IV. The use of underground piping by itself would not cause necessarily a facility to be classified in Category IV or V.

An example is, but not limited to:

—Land treatment.

2. Consequences of loss of control. In this category, there is no requirement for containment under treatment or storage units in the facility which might contain hazardous waste, and therefore, a spill or rupture could cause ground or surface water degradation. The restrictions included in this category would, however, minimize the possibility for leaks to go undetected for a significant length of time.

For the purpose of siting criteria, the consequences of loss of control are:

a. Fire or explosion, or both.

b. Airborne contamination, in the case of facilities which have the potential as described under Category III above.

c. Ground or surface water contamination.

d. Soil contamination.

E. Category V—Disposal without complete treatment and all other treatment/disposal methods.

1. Description. This category includes any disposal of hazardous waste by placing it in a facility where it will receive no further treatment or any treatment or storage method which does not meet the intent of one of the four categories above.

Facilities in this category would include all land disposal methods which did not involve destroying the waste or otherwise eliminating its hazardous characteristics before disposal.

This category would also include the use of such facilities as impoundments, lagoons, evaporating ponds, underground tanks, or other underground units as part of a treatment, storage or disposal process, providing that they are intended to contain hazardous waste. For this purpose, the term "underground" means that all or part of a unit is buried such that it cannot be routinely inspected for leaks or defects.

An example is, but not limited to:

—Land disposal.

2. Consequences of loss of control. These facilities have the highest degree of risk of surface or groundwater degradation because of the possibility for a leak to go undetected for a significant period of time. For disposal of units in this category there is also the added consideration of the risks associated with perpetual care of material which might be hazardous for many years. Facilities in this category could also be most prone to loss of control caused by floods.

For the purposes of siting criteria, the consequences of loss of control are:

a. Fire or explosion, or both.

b. Airborne contamination from evaporation or from sources described in Category III above.

c. Ground or surface water contamination.

d. Soil contamination.

F. General. Most facilities include several types of operation. For the purposes of classifying a proposed facility, the operation within the facility which is characterized by the highest category number shall determine which category shall characterize the facility. For example, if a facility had an operation which included both drum storage of waste under conditions that would meet Category I requirements and subsequently had on-site waste incineration step, the facility would fall in Category III because incineration is in a higher category than container storage. Another example might be a waste treatment facility with a completely enclosed neutralization process in which sulfuric acid contaminated water was mixed with lime. In this process, venting is not a significant part of the process. The result would be gypsum and water, neither of which would necessarily be hazardous material. If this process were fed from enclosed storage tanks the facility would be classified in Category II, assuming it met all the other requirements, because the enclosed neutralization process is in a higher category than enclosed storage. This would be true even if the gypsum were dried and piled on the ground and the water, after the acid was neutralized, was put in a pond prior to discharge into a river through a permitted waste water treatment facility, assuming that neither the gypsum nor the water would be classified as hazardous because of some other contaminant. If, however, in this latter example, the process generated a gas which needed to be vented to the atmosphere or which could be vented by a relief valve in an overpressure situation, the facility would have to be classified as Category III. Additionally, if the acid contaminated water was fed into this neutralization process from a pond (surface impoundment), the facility would be classified in Category V.

In making its determination of which category is appropriate for a proposed hazardous waste facility, the board shall consider the intent of each category as well as the specific descriptions above.

Historical Notes

Derived from VR672-01-5 § 2.2, eff. April 30, 1986; amended, Volume 21, Issue 20, eff. July 13, 2005.

Statutory Authority

§§ 10.1-1434 and 10.1-1436 of the Code of Virginia.