OAR 340-043-0180
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Guidelines for Open-Pit Closure

(1)

Open pits that will be left as a result of the mining operation shall be assessed prior to, and following, mining operations for the potential to contaminate water to the extent that it might not meet water-quality standards due to buildup of acid or toxic metals.

(2)

If the Department finds that the potential for water accumulation in the pit(s) exists, the permit applicant shall submit a closure plan for the pit that will address contamination prevention and possible remedial treatment of the water. The closure plan shall, at a minimum, examine the following alternatives:

(a)

Avoidance, during mining, of acid-generating materials that can be left in place, rather than being exposed to oxidation and weathering;

(b)

Removal from the pit and disposal, during or after the mining operation, of residual acid-generating materials that would otherwise be left exposed to oxidation and weathering;

(c)

Protective capping in-situ of residual acid-generating materials;

(d)

Treatment methods for correcting acidity and toxicity of accumulated water;

(e)

Installation of an impermeable liner under ponded water to prevent groundwater contamination;

(f)

Backfilling of the pit(s) to the level necessary to, in conjunction with other appropriate control measures, prevent oxidation of residual acid-generating materials.

Source: Rule 340-043-0180 — Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Guidelines for Open-Pit Closure, https://secure.­sos.­state.­or.­us/oard/view.­action?ruleNumber=340-043-0180.

340–043–0000
Purpose and Policies 340–043–0010
Definitions 340–043–0020
Permit Required 340–043–0025
Permit Conditions on Assumption of Liability 340–043–0030
Permit Application 340–043–0040
Plan and Specifications 340–043–0050
Design, Construction, Operation and Closure Requirements 340–043–0060
Exemption from State Permit for Hazardous Waste Treatment or Disposal Facilities 340–043–0070
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Purpose 340–043–0080
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: General Provisions 340–043–0090
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Control of Surface Water Run-On and Run-Off 340–043–0100
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Physical Stability of Retaining Structures and Emplaced Mine Materials 340–043–0110
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Protection of Wildlife 340–043–0120
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Guidelines for Design, Construction, and Operation of Heap-Leach Facilities 340–043–0130
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Guidelines for Disposal of Mill Tailings 340–043–0140
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Guidelines for Disposal or Storage of Wasterock, Low-Grade Ore and Other Mined Materials 340–043–0150
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Guidelines for Heap-Leach and Tailings Disposal Facility Closure 340–043–0160
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Post-Closure Monitoring 340–043–0170
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Land Disposal of Wastewater 340–043–0180
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: Guidelines for Open-Pit Closure
Last Updated

Jun. 8, 2021

Rule 340-043-0180’s source at or​.us