Township of Eureka, MN Article V Mineral Extraction Performance Standards

§ 165-13 Performance standards.

The following performance standards apply to all mineral extraction facilities in the Township:

A. Hours of operation. Mineral extraction facilities shall operate only between the hours of 7:00 a.m. and 5:30 p.m., Monday through Friday. A mineral extraction facility may be opened one hour before hours of operation to allow for staging. No Sunday or holiday operations will be allowed. The holidays are New Year's Day, Memorial Day, July Fourth, Labor Day, Thanksgiving and Christmas. When New Year's Day, July Fourth, Thanksgiving or Christmas fall on a Sunday, the following Monday shall be considered the holiday. When New Year's Day, July Fourth, Thanksgiving or Christmas fall on a Saturday, the previous Friday shall be considered the holiday.

(1) Operators are allowed extensions to the hours of operation for emergencies only. Operators must notify the Township Clerk or a Town Board member in advance of the proposed exception.

(2) The Town Board must approve other exceptions to the hours of operation, such as Saturday operation, government agency contracts and other evening work.

B. Source of minerals. Only minerals from the site shall be processed at the mineral extraction facility; subject, however, to the following exceptions:

(1) The operator may import off-site minerals onto the subject property for the purpose of mixing with minerals from the subject property provided the imported minerals on an annual basis do not exceed 25% of the minerals extracted from the subject property on an annual basis. Accessory uses may not exceed 25% off-site minerals used in conjunction with each specified accessory use; therefore, off-site minerals may not be aggregated to a single accessory use, allowing a specific accessory use to exceed 25% of off-site minerals used in conjunction with the specific accessory use.

C. Site security. Security must be sufficient to protect the community from attractive nuisances. The burden to design and install sufficient security is on the operator and owner who are expected to stay current with industry practices and to stay aware of all risks at the mining facility. If not already included in the security system put in place by the mine, fencing may be required by the Town Board around any section and/or the entire mineral extraction area. When used, fencing at a minimum must be three wires with posts a maximum of 12 feet apart and at least four feet high and in good repair. Berming, no trespassing signs, locked gates at access points, security cameras and lighting including motion sensitive units, and any other site security can also be considered by the Town Board to mitigate the need for fencing on certain areas. The Town Board may require fencing, signs and/or barriers around ponding areas and steeply sloped excavations.

D. Access. All mineral extraction facilities shall have direct access to a nine-ton or greater capacity road. The Town Board shall set minimum roadway improvements and maintenance obligations as a condition of the permit. The point of the mining site access shall be at least 300 feet from any intersection or residential driveway, or as determined by the Town Board under special circumstances. Circumstances will include, but not be limited to, topography, safety, traffic, and existing land use.

E. Haul routes. All trucks traveling to or from the mineral extraction facility shall utilize nine-ton or greater road capacity within the Township. Operators may be granted a special permit to utilize roadways temporarily posted under nine tons, provided adequate surety is provided to cover the costs of repairing any damage to roadways. The Town Board may allow a Level 1 permit holder to use roads that are not nine-ton. Level 2 and Level 3 permits will require any substandard roads utilized by the mineral extraction facility as haul routes to be brought up to a MnDOT standard for nine-ton paved roads. The operator will bear the cost of such an upgrade. The Township reserves the right to require road maintenance paid by the operator on any haul route within the Township or those bordering the Township. Traffic control to assure safety must be maintained. Trucks shall not queue on public roads while waiting to enter or exit facility. Turn lanes shall be constructed on public roads if deemed necessary by the appropriate road authority, at landowner and/or operator expense. Sufficient truck staging area shall be provided on mineral extraction facility property.

F. Roadway dust control. Operators will be responsible for dust control on all gravel roads utilized by trucks hauling to or from the mineral extraction facility. Dust control will be required when conditions warrant it and the number of one-way truck trips from the mineral extraction facility exceeds three per hour. The Township reserves the right to require the operator to pay for dust control on any haul route within the Township or those bordering the Township. An operator will consult with, and receive permission from, the Road Supervisor prior to adding gravel or grading a Township road.

G. Mineral extraction facility dust control. The Township shall require dust control in a facility when it is determined that airborne dust from extraction areas, processing activities, stockpiles or internal roadways creates a public nuisance or otherwise adversely impacts surrounding lands. Remedies to dust control may include watering, berming, landscaping and enclosures for processing equipment, and any other means deemed necessary by the Town Board.

H. Noise. Maximum noise levels at the facility will be consistent with the most current standards established by the Minnesota Pollution Control Agency (MPCA) and as deemed necessary by the Town Board.

I. Vibration. Operators shall use all available means deemed necessary by the Town Board to eliminate adverse impacts of vibration from equipment on adjacent properties.

J. Air quality/water quality. All activities on the subject property will be conducted in a manner consistent with operating permits issued by state and federal agencies. The Town Board may require other standards it deems reasonably necessary. Increased runoff must be retained on site with retention or detention ponds.

K. Accessory uses. Accessory uses must be identified in the permit. Accessory uses not identified in the permit are not allowed. The accessory uses of a concrete block production plant, a ready-mix concrete production plant, a concrete recycling plant asphalt production plant, or an asphalt recycling plant shall be strictly prohibited. The storage, stockpiling, sale and mixing of minerals that have been excavated off site are strictly prohibited, except for the mixing of minerals as provided in § 165-13B, as limited to minerals. Accessory uses will terminate when the principal use terminates. Accessory uses may not collectively account for more than 25% of the total mine operations based upon the volume of minerals extracted from the subject property, so that primary uses account for greater than 25% of the total mine operation as measured by volume.

L. Unauthorized storage. Any vehicles, equipment or materials not associated with the mineral extraction facility or not in operable condition may not be kept or stored at the facility.

M. Setbacks. No extraction activity may occur within 1,000 feet of any dwelling and within 50 feet of any adjacent property line, road right-of-way or public utility. Screeners, crushers, other processing equipment and manufacturing equipment may not be located closer than 1,000 feet from a dwelling nor closer than 100 feet from any adjacent property line, road right-of-way or public utility. Setbacks from an existing dwelling shall take precedence over setbacks for road right-of-way, adjacent property line and public utility. Grading plans affecting pipelines or power line corridors will be evaluated on a case-by-case basis. The Town Board may waive setback requirements when the common boundary area of an adjoining property is also a legal mining operation, the common boundary is not within 1,000 feet of a residence, and both property owners of adjacent mining operations have agreed to a common reclamation plan and have a written agreement with the Township establishing responsibility for reclamation. Any existing approved setback reduction in an existing approved interim use permit continues to have approved status.

N. Phasing. Phasing plans must be prepared for all mineral extraction facilities. The operator and landowner must follow the phasing plan approved by the Town Board. No more than 10 acres of land may be exposed to extraction at any one time. A maximum of 25 acres may be utilized at any one time for extraction, processing, staging and stockpiling. Areas where extraction has been completed shall be reclaimed according to the provisions of this chapter, except for that area currently being used in the maximum twenty-five-acre operational area.

O. Berming. Earthen berms shall be constructed along all road rights-of-way. In the instance where the setback from a residence applies under § 165-13M, then, in addition, earthen berms shall be constructed along the adjoining property line. Berms shall provide screening of the mining activity from the right-of-way and any adjoining property line on which a berm is required. A combination of berms and other screening which has no written objection from any owners of real property located within 1,000 feet of the proposed extraction activity may satisfy this requirement, subject to Town Board approval of the design. In the absence of such an alternate design, berms shall be a minimum of eight feet in height. All berms shall have a minimum slope of 3:1 and have a silt fence at the base on the side closest to adjacent property. The silt fence shall be maintained until vegetation is established; at which time it shall be removed.

P. Heights. The maximum height of any excavation, temporary crushing equipment, or temporary stockpiles located no less than 1,000 feet from the property line shall be a minimum of eight feet below the average height of the adjacent berms within the mandatory setback.

Q. Weed control. The operator shall be required to control noxious weeds and mow or harvest other vegetation to maintain reasonable appearance of the site.

R. Explosives. If the operator desires the use of explosives, a separate interim use permit shall be required for each incident to provide adequate public notice and input.

S. General compliance. The operator must comply with all other federal, state, regional, county and local laws and regulations applicable to the operation of the mineral extraction facility, including but not limited to mine safety and health rules, floodplain management regulations, shoreland management regulations and zoning regulations. No use or structure shall be operated or occupied in such an amount or to such a degree or intensity as to constitute a hazardous condition, or as to unreasonably interfere with the use of other property by any person of normal sensitivities or to otherwise create a public nuisance.

T. Additional regulations. The Township may impose additional regulations and requirements on the mineral extraction permit to protect the public health, safety, and welfare.

U. Reclamation. The operator must meet the following minimum standards and conditions regarding reclamation.

(1) Reclamation plan. The operator must submit a reclamation plan containing the following elements:

(a) Intent of reclamation;

(b) Methods and processes of reclamation;

(c) Initial condition of mining site;

(d) Limits of various operational areas;

(e) Phasing and timing of operations and reclamation including areas to be stripped of overburden;

(f) Grading plans, on-site topsoil replacement, seeding, mulching, erosion control and sedimentation control specifications;

(g) Final condition of site, including proposed contours and absolute elevation with respect to the average annual water table, and a potential development plan, if applicable;

(h) Relation of final site condition to adjoining landforms and drainage features;

(i) Relation of reclaimed site to planned or established uses of surrounding land;

(j) A plan for maintenance of reclaimed area; and

(k) A detailed cost estimate of reclamation.

(2) Reclamation timing. The timing of reclamation activities shall comply with the following:

(a) It is expected that reclamation will be occurring in phases. Reclamation shall also be completed in step with the opening of new excavation areas of the facility. As-built surveys, soil borings, water table elevation determination, or other testing may be required as part of the review to ensure phased reclamation is completed according to the approved reclamation plan.

(b) Reclamation shall proceed in a continuous manner throughout the duration of the mining operation and is subject to review and approval at each annual inspection and at the end of the permit period.

(c) Within three months after the termination of excavation operations or within three months after the expiration of the interim use permit, the operator or landowner shall dismantle buildings and structures incident to mining operation and shall grade the excavation site as well as complete all rehabilitation on the site as provided in the approved reclamation plan.

(3) Water accumulations. Excavations in a Level 3 mine, resulting in the continued exposure of substantial water areas after reclamation must meet the following requirements (all other levels of mines shall not result in water table exposure):

(a) The water depth must not be less than three feet measured from the average annual water table elevation as measured by piezometer or monitoring well unless a plan for creation of a wetland or marsh has been approved.

(b) All banks shall be sloped to the water line at a slope which shall not be steeper than four feet horizontal to one foot vertical.

(c) All banks shall be surfaced with topsoil of a quality at least equal to the topsoil of land areas immediately surrounding and to a depth of at least four inches. All banks shall also be surfaced with sodding or seeding and mulching. Mulch must be properly anchored.

(d) All topsoil required by the subsection U(3)(c) above shall be planted with trees, shrubs, grasses, or native vegetation, or return to agricultural use.

(e) Slopes on reclaimed areas shall not be steeper than four feet horizontal to one foot vertical, except in cases where nonerodible conditions are present, and the Planning Commission approves the reclamation plan.

(f) In man-made groundwater lakes, the bottom contour shall be gradually sloping from the shoreline to the deepest portion of the water body at a maximum slope of six feet horizontal to one foot vertical for at least 100 feet from the shoreline toward the center of the water body. Beyond 100 feet horizontal distance from the shoreline, the slope of the bottom may be no steeper than three feet horizontal to one foot vertical.

(g) All groundwater lakes or wetlands created as part of the reclamation plan shall comply with state, county, and local laws, regulations, ordinances, requirements, and guidelines, including Minnesota Department of Natural Resources guidelines for surface water creation.

(4) Grading and backfilling. Excavations not resulting in surface water creation after reclamation, but which must be graded or backfilled, shall meet the following requirements:

(a) Fill of soil shall be inspected and certified as being clean (free of volatile organic compounds, contaminants, noxious weed seeds and heavy metals) before being used for reclamation; only organic soil shall be used for topsoil.

(b) Fill of soil shall consist of nonnoxious, nonflammable, noncombustible solids.

(c) The graded or backfilled area shall not collect or permit stagnant water to remain therein.

(d) The peaks and depressions of the area shall be reduced to a gently rolling topography in substantial conformity to the land area immediately surrounding and which will minimize erosion due to rainfall.

(e) Graded or backfilled areas shall be surfaced to a depth of at least four inches with topsoil of a quality at least equal to the topsoil of immediately surrounding areas.

(f) Topsoil required by Subsection U(4)(f) above shall be planted with trees, shrubs, grasses, or native vegetation, or return to agricultural use; and inspected to be free of noxious weeds.

(g) Slopes on reclaimed areas shall not be steeper than four feet horizontal to one foot vertical, except in cases where non erodible conditions are present, and the Planning Commission approves the reclamation plan.

(h) All reclamation areas which are planned for building purposes shall have a final elevation at least 10 feet above the normal ordinary groundwater level. If public sewer is not available, plans for on-site septic systems must be considered. If the area is backfilled for purposes of future development, the soil must be compacted, and subsequently tested and approved by a licensed soils engineer.

(i) Drainage. Reclamation shall proceed in a manner that preserves natural and storm drainage entering and leaving the premises. Said drainage shall be altered to the least extent necessary for carrying out reclamation and related activities. Natural and storm drainage shall not be altered in a manner that adversely affects public roads or neighboring uses.

(j) Cover and planting. The reclamation area shall be planted with grass, trees, shrubs, or other vegetation to prevent erosion and provide screening and improved aesthetics. Technical assistance and soils data should be obtained from the county agricultural agent, appropriate state and federal officials, conservation districts, and the nearest soil conservation service officer.

(k) Topsoil. Topsoil that is stripped or removed must be stockpiled and set aside on the site for re-spreading over the reclaimed area unless the quantity is sufficiently in excess of need that the Town Board approves plans for its removal.

(l) Removal of structures. All buildings and other structures not otherwise allowed per the development agreement shall be removed from the property and the property shall be restored in conformance with the reclamation plan within three months after expiration of a mining permit or termination of a mining operation or within three months after a mining operation has been abandoned for six months.

(m) Best practices for preservation and restoration of soil. In order to protect the environment and the public's health, safety, and welfare, applications shall incorporate best practice standards into the design, operation, and reclamation of mineral extraction facilities. A list of best management practices for the preservation and restoration of soil is available through the Minnesota Department of Natural Resources at: https://www.dnr.state.mn.us/water_access/bmp/soil_retention_bmp.html. The Town Board reserves the right to supplement these standards as appropriate.

(5) Soil and Water Conservation District and watershed review and recommendations. As a part of the original application for an interim use permit, the operator shall submit grading plans, phased reclamation plans and water control plans to the Dakota County Soil and Water Conservation District and to the governing bodies of the Township's watersheds for review and recommendations. Said recommendations on the phased reclamation, grading, soil, and water retention plans shall be reviewed annually by the Town Board and may be included as conditions of the interim use permit.