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6.4. RIA of the Supplemental Proposed Rule Applying Phase IV Land Disposal Restrictions to Newly Identified Mineral Processing Wastes

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After a lengthy legislative, regulatory and judicial history, numerous mineral processing waste streams lost their exemption from regulation under the Resource Conservation and Recovery Act (RCRA). The subject document is a regulatory impact analysis of a proposed rule to control those newly identified wastes.

The document considers four regulatory options.

The first, and preferred, option would establish UTS [Universal Treatment Standard] as the BDAT [Best Demonstrated Achievable Technology] treatment standard for all hazardous mineral processing wastes being disposed on the land. It also would establish a conditional exclusion for such wastes destined for reclamation and managed on the ground, thereby providing regulatory relief to the operators of mineral processing operations, who commonly both reintroduce materials to various parts of the production process and store such materials on the land. …

The second option also would establish UTS standards for all newly identified mineral processing wastes destined for land disposal, but make no changes to existing regulatory provisions. The third option is identical to Option 1 except that the conditional exclusion would apply only to spent materials. The fourth option has been advanced by the National Mining Association and would codify a very limited set of management controls for hazardous mineral processing wastes. (p. 1-5)

Options 1 and 2 receive the great bulk of the attention throughout the document.


Much of the modeling in the document bears on both the cost and benefit side of the analysis. First, 526 waste streams were identified at mineral processing facilities. Ibid., p. 3-11. EPA then pruned the list to 147, eliminating the others because they were legally exempt, already recycled, not hazardous and for other reasons. Ibid., p. 3-12. At a later step, the affected mineral processing facilities were identified. Ibid., p. 3-16. Minimum, expected and maximum compliance cost cases were devised. Ibid., p. 3-18.

EPA then totalled each of the estimated waste stream generation rates by costing scenario (i.e., minimum, expected, and maximum) to arrive at total waste generation rates by mineral commodity sector. (p. 3-18)

Costs are uncertain in another dimension as well:

Because the extent to which operators of mineral processing facilities are currently treating their hazardous wastes is largely unknown, EPA has performed analyses of regulatory impact using two different baselines. Under one, referred to … as “no prior treatment,” such wastes are assumed to be managed, untreated, in unlined surface impoundments and waste piles … This baseline is functionally equivalent to the assumption that the regulated community is not in compliance with existing Subtitle C [of RCRA] waste management standards. Under the other, alternative baseline, operators are assumed to be in full compliance with Subtitle C requirements. (p. 4-2)

Differences in estimated cost impact between the two baselines are both dramatic and simple. Under the no prior treatment baseline, the operator would be assumed to incur the expense … to treat the hazardous wastes to UTS levels for the first time … Under the prior treatment baseline, these costs would already have been incurred … Thus, impacts associated with applying UTS standards would be essentially zero. (p. 4-3)

There are two principal options, two baselines and three “costing” scenarios yielding twelve possible costs. A table of those costs is reproduced here. Ibid., Exhibit 7-1, p. 7-2.

Summary of Costing Analysis Results
(Results in $ Million per Year)

OptionCosting ScenarioBaseline Assumption
Prior TreatmentNo Prior Treatment
1 – Contingent
2 – ConventionalMinimum050.9

Enforcement costs are not considered.


The document discusses some benefits and, in a sense, quantifies other benefits. There is no monetization of benefits.
The quantified benefits are reductions in cancer and non-cancer health risks resulting from groundwater consumption.

… the daily groundwater consumption rate used for intake estimation was 1.4 liters … for a 70-kg adult. The intake frequency was assumed to be 350 days/year over a nine-year period for both cancer and noncancer risk calculations. (p. 5-11)

The epidemiological model is very complex. It involves assumptions about the content and transport of groundwater and about the dose-response reaction of receptors. In addition, the calculations are made assuming different baselines, different regulatory options, central tendency (CT) and high end (HE) dose-responses. Further, mean-release concentration estimates are refined where appropriate into sample-specific concentration estimates.

The aim of the exercise is to develop tables showing how risk is distributed before and after regulation, i.e., the lifetime risk of developing cancer. Loosely speaking, these tables characterize before and after density functions. A parallel measure, a hazard quotient, is presented for non-cancer illnesses.

Of particular concern to EPA are the numbers of facility-waste stream combinations at which risks exceed levels of regulatory concern under the baseline assumptions and regulatory options. In this analysis, an individual cancer risk level of 10-5 and a noncancer hazard quotient value of 1.0 have been selected as levels indicative of potential concern. (p. 5-22)

Under Option 1 [and the no prior treatment baseline and the mean-concentration model], the estimated numbers of facility-waste stream combinations with CT cancer risks greater than 10-5 is reduced only slightly, from 68 out of 98 to 62 out of 98. (p. 5-27)

The numbers of facility-waste stream combinations with CT noncancer hazard quotients greater than 1.0 decreases dramatically … Under the baseline case, 71 of 136 facility/waste stream combinations had CT hazard quotients greater than 1.0. Under Option 1, this number was reduced to zero. (p. 5-28)

Large shifts are seen in the distributions of facility-waste stream combinations from both CT and HE assumptions, indicating that substantial health benefits from reduced groundwater exposure to toxic contaminants may be realized. (p. 7-5)

Because benefits are not monetized, there can be no calculation of net benefits. Some benefits are quantified but in terms of probability distributions precluding cost-effectiveness calculations as well.

Other Impacts

The document considers regulatory flexibility, environmental justice and unfunded mandates. Regarding regulatory flexibility,

… the Agency had to consider that due to the statutory requirements of the RCRA LDR [Land Disposal Restriction] program, no legal avenues exist for the Agency to provide relief from the LDRs for small entities. (p. 6-5)

The document sees no problem with the rule regarding environmental justice:

Today’s rule is intended to reduce risks from mineral processing wastes, and to benefit all populations. It is, therefore, not expected to result in any disproportionately negative impacts on minority or low income communities relative to affluent or non-minority communities. (p. 6-5)

Neither is there a problem regarding unfunded mandates:

EPA has completed an analysis of the costs and benefits from today’s proposed rule and has determined that this rule does not include a federal mandate that may result in estimated costs of $100 million or more to either state, local or tribal governments in the aggregate. (p. 6-6)

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