A. Standard Hours and/or Days of Operation. No mechanical equipment shall be operated before the hour of 6:00 a.m. and no later than the hour of 7:00 p.m., six days per week. No mechanical equipment shall be operated on Sundays or legal holidays. These restrictions are not intended to preclude the service and maintenance of the machinery and equipment necessary for the mining operation.

The standard hours and/or days of operation may be reduced by the hearing examiner if determined to be in the best public interest, so long as the reduction does not conflict with or violate a city code, ordinance or adopted requirement or regulation.

The standard hours and/or days of operation may be modified for specific public works projects involving mixing of asphalt or concrete that is either:

A written request from the public agency whose project requires the work to be performed outside the standard hours and/or days of operation shall be made to the Auburn public works director. The request shall be in writing and be provided to the Auburn public works director not later than 10 days prior to the commencement of the project. The request shall include the name and location of the project, the proposed modifications to the standard hours and/or days of operation, and the estimated duration (subject to the weather) of the project, and a statement why the modification is in the best public interest and will facilitate the completion of the project.

If the request is determined by the public works director to be in the best public interest, that it will facilitate the completion of the pubic works project and will be consistent with any applicable city requirement the public works director shall, within five days of its receipt, approve the request.

B. Finished Slopes. The site plan shall illustrate which finished slopes are final and which ones are interim. Final finished slopes are those that will not be modified subsequent to the completion of mining. Interim slopes are those which will be modified subsequent to the completion of mining. Final finished slopes are not allowed to be altered unless for public safety and health reasons, once the mining has been completed and that portion of the mine rehabilitated. Interim finished slopes may be altered, pursuant to applicable city regulations, to accommodate the subsequent development of the site once the mining has been completed.

In the event that fills are necessary such fills shall be compactible to a minimum of 90 percent maximum density; said density shall be certified by a soil testing agency. No organic materials shall be permitted in fills.

C. Fences, Landscaping and Berms. Fences, landscaping and/or berms may be required to mitigate any impacts associated with the mining site.

D. Noise. Sound pressure levels, as measured on properties adjacent to property in the mining site, shall conform to the provisions of WAC 173-60-040, Maximum Permissible Environmental Noise Levels for Noise Originating in a Class C-EDNA (Industrial Area).

E. Blasting. Blasting shall be allowed pursuant to the permit requirements of the fire marshal’s office.

F. Rock Crushing. A rock crusher may be permitted if expressly allowed through the surface mining permit. The location of the crusher may be conditioned in order to mitigate any noise impacts.

G. Dust. Dust, dirt, fly ash, or other particulate matter shall not be emitted in quantities as to adversely affect adjacent property. Reasonable precautions shall be taken with storage, transportation, processing, roadways and other open areas so as to prevent the particulate matter from becoming airborne. It shall be sufficient cause to revoke a permit if the operator causes or permits untreated open areas located within a private lot or roadway to be maintained without taking reasonable precautions to prevent particulate matter from becoming airborne.

H. Setbacks. No excavation shall occur within 50 feet of an adjoining property unless a lesser setback is necessary in order to attain proper reclamation. The setbacks shall be determined at the time of permit issuance. When the mining is complete and the site reclaimed, the 50-foot setback may be modified at that time to provide for the subsequent development. This shall be reviewed pursuant to applicable city regulations.

I. Department of Natural Resources Permit. Prior to a surface mining operations permit being applied for the owner/operator shall submit evidence from the State of Washington Department of Natural Resources that the state considers the proposal as a surface mine and will require a permit and reclamation plan.

J. Paved Apron. A paved apron or similar device, wash pits or similar provisions may be required in order to prevent rocks, dirt, and mud being tracked onto public streets, the width and depth to be determined at the time of permit issuance.

K. Street Cleaning. All adjacent public streets shall be kept clear of rocks, dirt and mud. Street sweeping and washing may be required as a condition of permit issuance.

L. Traffic Control. Warning signs and/or flaggers may be required as a condition of permit approval.

M. Inspections. The city shall have the right to make inspections of any property at any reasonable time as deemed necessary to determine compliance with the permit and/or obtain surface and well water samples. The city shall notify, as deemed necessary, any operator of a proposed inspection, however, lack of such notification shall not be cause for denying the right to inspect. The operator shall have the option of accompanying the inspector.

N. Adjacent Wells or Aquifers. The mining operation shall not result in the degradation of groundwater quality in shallow, intermediate or deep aquifer zones, located beneath and beyond the boundary of the active area of the mining site, which serve as the source of potable supply for the city or private citizens, or possess water of sufficient quality and quantity to be developed for future potable and/or municipal supply purposes.

In the event that actual or potential groundwater quality degradation caused by mining operations is indicated on the basis of inspections, on-site release of hazardous materials, violations of water-quality provisions of other ordinances, or off-site groundwater quality degradation documented in on-site or off-site wells, the city shall have the right to require the operator of the mine to immediately cease that portion of the mining operations (subject operations) which in the city’s opinion caused the degradation and submit to the city a groundwater remediation plan prepared by a licensed engineer. At a minimum the plan shall:

The subject operations shall be suspended pending city review of the plan and determination of adequacy, both of which shall occur within 15 days of submittal. If the city does not approve the plan, require modifications, or if the mining operator fails to submit a plan, the subject operations shall remain suspended until the mining operator makes the revisions directed by the city and/or until the mining operator submits an acceptable groundwater remediation and monitoring plan. If the revised groundwater remediation and monitoring plan submitted by the mining operator is approved by the city, the subject operations shall be permitted to resume upon the date the city approves the plan. Such approval shall not occur later than 15 days after the revised plan has been submitted.

If subsequent to the city’s approval of the mining operator’s groundwater remediation and monitoring plan the city determines that the mining operator has failed to comply with all of the provisions of the plan, or that a plan has failed to immediately halt and/or remediate the groundwater degradation caused by the mining operation, the city may direct the mining operator to suspend subject operations, pending demonstration of compliance with the plan and/or approval by the city of a revised plan. Revised plans submitted to the city shall be reviewed for decision within 15 days of submittal. Once approved the city shall immediately notify the mining operator that subject operations may resume if in compliance with the approved plan.

Additional setbacks or limitations on the depth of excavation may be required to protect adjacent wells or aquifers.

O. Performance Bond. If a performance bond is required to guarantee the performance of these standards or any conditions attached to the permit it shall be submitted prior to the adoption of the ordinance. The value of the bond shall be determined as part of approval of the surface mining operations permit. The bond shall be written to the city of Auburn only, and shall not be canceled without the express written approval of the city of Auburn.

P. Importing of Materials. The importing of materials, e.g., sand or topsoil, may be permitted if needed as part of the mining activity. These imported materials could be used for preparing the mining site for reclamation or blending with the on-site materials to provide for a better fill or construction product that is then exported. The import of materials that are only to be stockpiled, and are not related to the mining activity, will not be permitted. (Ord. 6185 § 4, 2008; Ord. 5060 § 1, 1998.)