OAR 340-043-0080
Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: General Provisions

(1)

Facilities permitted under either a WPCF or NPDES permit shall not discharge wastewater or process solutions to surface water, groundwater or soils, except as expressly allowed by the permit.

(2)

Facilities subject to these rules shall not be sited in 100-year floodplains or wetlands. A buffer zone (a minimum of 200 feet wide) shall be established between waste disposal facilities and surface waters.

(3)

All chemical conveyances (ditches, troughs, pipes, etc.) shall be equipped with secondary containment and leak detection means for preventing and detecting release of chemicals to surface water, groundwater or soils.

(4)

Acid water accumulation in open pits resulting from the mining operation must be prevented by appropriate mining practices, by measures taken in the closure process, or be treated to control pH and toxicity, for the life of the pit.

(5)

Construction of surface impoundment liner systems shall conform generally to the principles and practices described in EPA/600⁄2-88⁄052, Lining of Waste Containment and Other Impoundment Facilities, September 1988.

(6)

The Department may require the permittee to hire a third-party contractor to perform the functions set forth below. Selection of the contractor shall be subject to Department approval:

(a)

Review and evaluate the design and construction specifications of all mined-materials disposal facilities permitted under this Division for functional adequacy and conformance with Department requirements. The Department shall not approve construction of the disposal facilities until the design and construction specifications have been evaluated;

(b)

Monitor the course of construction of all mined-materials facilities for compliance with the approved design and construction specifications. The third-party contractor shall regularly document the progress of construction and the Department shall require the permittee to take corrective action if construction does not satisfactorily conform to the approved design and construction specifications;

(c)

Provide on-site inspections during ongoing operations, including but not limited to the loading of the heap, to assure protection of the integrity of the liner system and other environmental protection measures.
[Publications: Publications referenced are available from the agency.]

Source: Rule 340-043-0080 — Guidelines for the Design, Construction, Operation and Closure of Chemical Mining Operations: General Provisions, https://secure.­sos.­state.­or.­us/oard/view.­action?ruleNumber=340-043-0080 (accessed May 26, 2025).

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

May 26, 2025

Rule 340-043-0080's source at or​.us