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HomeMy WebLinkAbout2019-01-28 PACKET 06.2. STAFF REPORT CASE: MP19-002 ITEM: 6.2 PUBLIC MEETING DATE: 1/28/19 TENTATIVE COUNCIL REVIEW DATE: 2/20/19 APPLICATION APPLICANT: Aggregate Industries – North Central Region, Inc. REQUEST: 2019 Mining Permit to continue their mining operations on Lower Grey Cloud Island (Nelson Mine). SITE DATA LOCATION: 11250 Grey Cloud Trail South ZONING: I-4, Commercial Excavation District GUIDED LAND USE: Transition Planning Area LAND USE OF ADJACENT PROPERTIES: CURRENT GUIDED NORTH: Mooers Lake Mooers Lake EAST: Rural Residential Rural Residential SOUTH: Mississippi River Mississippi River WEST: Mississippi River Mississippi River SIZE: Stripping and Mining Area = approximately 9 acres DENSITY: RECOMMENDATION Approval, based on the findings of fact and subject to the conditions stipulated in this staff report. COTTAGE GROVE PLANNING DIVISION Planning Staff Contact: John McCool, Senior Planner; 651-458-2874; jmccool@cottage-grove.org Application Accepted: 1/2/2019 60-Day Review Deadline: 3/3/2019 City of Cottage Grove Planning Division  12800 Ravine Parkway South  Cottage Grove, MN 55016 Planning Staff Report Aggregate Industries – Annual Mining Permit Planning Case No. MP2019-002 January 28, 2019 Proposal Aggregate Industries – North Central Region, Inc. has submitted their annual mining permit ap- plication to continue mining and processing aggregate materials in the Nelson Mine located at 11250 Grey Cloud Trail. The aggregate materials will be incorporated into various products in the Twin Cities metropolitan area and are used for ready mix concrete and/or asphalt in the construction of highways and buildings, etc. The 2019 Mining Operations Plan proposes the following:  Mining and processing approximately 800,000 to 850,000 tons of aggregate materials.  Clear cutting and stripping topsoil on approximately nine acres northwest of the existing dredge location.  Dredging at an average depth of 90 feet and in some areas to a depth of 125 feet below the normal water level.  Processing, washing, screening, and loading aggregate materials onto barges and trucks.  Operating 24 hours per day seven days a week. Location Map A copy of Aggregate Industries – Nelson Plant 2019 Operation Plan is attached. Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 2 of 11 Review Process Application Received: January 2, 2019 Acceptance of Completed Application: January 2, 2019 Tentative City Council Date: February 20, 2019 60-Day Review Deadline: March 3, 2019 Ordinance Requirements City Code Title 3-10 requires that an annual mining permit must be reviewed by the Planning Commission within 60 days after the completed application has been accepted by the City. The Planning Commission’s recommendation is forwarded to the City for final action. The purpose of the annual mining permit is to:  Ensure the restoration of the mined area is consistent with existing and planned land use patterns and to promote appropriate reuse of the mined areas;  Ensure conformity of mining operations with the City’s Critical Area and Comprehensive Plans;  Control the effects of noise, dust, erosion, traffic, drainage, ground water pollution, and other factors related to mining in general. Background In 1950, property owners Paul K. and Mary Schilling entered into a lease agreement with the J. L. Shiely Company (now known as Aggregate Industries) to mine sand and gravel on Lower Grey Cloud Island. Supplemental lease agreements have been negotiated over the years. In 2001, Ag- gregate Industries signed a new lease with the property owner, allowing mineral extraction on the Island for 20 years. Aggregate Industries projects that sand and gravel resources within the existing Nelson Mine could be mined for another 15 to 20 years. Aggregate Industries has tempo- rarily suspended the preparation of an Environmental Impact Statement for mining the area directly south of the eastern end of Lower Grey Cloud Island. This area was referred to as the “Mississippi River backwaters” adjacent to the main island. Aggregate Industries estimated that underwater mining the backwaters area would add an additional 20 years based on current market trends, geologic variations, and aggregate resources. Several studies and reports were prepared in the 1970s to serve as a guide in reviewing annual mining permit applications and reclamation plans. On October 12, 1982, the Lower Grey Cloud Is- land Reclamation Concept Plan was approved by a City of Cottage Grove Reclamation Commit- tee. A mining plan prepared by B.B. Chapman in 1982 is part of that document. A copy of this plan is shown below. With some exceptions, the proposed 2017 Operations Plan generally replicates landforms and topography as approved in 1982. Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 3 of 11 1982 Reclamation Plan In 2000, the property owners of the Nelson Mine site had a development concept plan prepared. The purpose of this concept plan was to show the landowners’ desired future uses within their property ownership. The plan proposed a commercial marina in the vicinity of the existing processing plant, mixed residential uses, commerical, and public open spaces. The concept plan is shown below. 2000 Concept Plan Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 4 of 11 In the 2019 Mining Permit application submittal, Aggregate Industries included a future land use plan for potential development that PAS Associates Limited Partnership and Aggregate Industries had Westwood Professional Services prepare. A copy of this plan is shown below. Future Land Use Plan by PAS Associates Limited Partnership, July 18, 2017 Dredge Operations A dredge is used to excavate raw aggregate materials. This dredge is of a “twin-clamshell” design and is one of the largest machines of its type. The dredge is a 100-foot by 100-foot by 60-foot high floating dredge that weighs approximately 550 tons. Assembly of the dredge was completed in 1995, and the dredge was equipped with sound-absorbing equipment in 1996. The dredge is used to reach sand reserves below the water surface. Its de-sanding capability and initial crusher that crushers rocks to smaller than six inches in size allows the operator to reclaim up to 400 tons of sand per hour without unnecessary re-handling. The dredge can mine 1,200 tons of aggregate material per hour at 60 feet below the water surface. This year’s mining plan continues to extract aggregate materials below the water surface that is between 90 to 125 feet. Mining Operations After the material is excavated by the dredge, the mined aggregate is transported by a conveyor system that is about 2.2 miles long to the processing plant located at the northwest side of Lower Grey Cloud Island. The processing operations include crushing, washing, sorting, and stockpiling aggregate materials by size. These materials are then loaded onto barges or trucks. Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 5 of 11 Most of the material is transported by barge up the Mississippi River to distribution yards in St. Paul and Minneapolis. Last year, approximately 720,000 tons (approximately 99.7 percent) of the materials were transported by barges. Approximately 2,000 tons (0.3 percent) were transported by truck along Grey Cloud Trail and 103rd Street to Highway 61. The trucks generally travel on Grey Cloud Trail to 103rd Street, east to Hadley Avenue, north to 100th Street, and then to U.S. Highway 61. The barge fleeting facility can store approximately 18 barges. A single barge can carry between 1,200 to 1,300 tons. A summary of the Nelson Mining operations since 2000 is attached. Planning Considerations Proposed Mining Operations The 2019 Operation Plan does propose to remove trees and brush from an area that is approxi- mately nine acres located west side of the existing dredging operation. Stripping of topsoil two to five feet in depth will be conducted in an area that is approximately nine acres in area. This area is located northwest of the existing dredging operation. Loaders, scrapers, and haul trucks will stock- pile this material for later reclamation or immediately be placed on a reclaimed area. The conveyor system will continue to be used for transporting the aggregate materials from the dredge to the processing plant. The conveyor system and dredge are electrically operated and ap- proximately 2.2 miles long. Sounds emanating from these activities have not been cause for any complaints from neighboring property owners. The site of the temporary concrete ready mix plant and temporary concrete bridge casting pro- duction plant was in the northwest corner of the Nelson Mine. This temporary facility was approved by the City in 2014 and removed from the site in 2017. Aggregate Industries will finish restoration of this area in a couple years. This area will be used for additional product storage and will be filled with 3 to 5 feet of waste sand or dredge sand before it is reclaimed. Depositing fill materials within the floodway and floodway fringe (below the 700-foot mean sea level eleva- tion) is prohibited. The 2019 Operation Plan is shown on the next page and a copy of this plan is attached to this planning staff report. Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 6 of 11 Proposed 2019 Operations Plan Like previous operation plans, the applicant is required to take appropriate measures to ensure there is no erosion to stockpiles or earth-berms. At the base of each slope, a channel must be con- structed to control runoff. The channeled water shall be diverted to a sedimentation basin before being allowed to enter any natural drainage system. Erosion control measures must be im- plemented within a reasonable amount of time for the stockpile and berm. Environmental Impact Statement Process The applicant is not proposing to mine within the Mississippi River backwaters or river channel dur- ing their 2019 operations. The 2019 Operation Plan does not show the once proposed dredging below the water surface of the Mississippi River, but this area is south of the southeast tip of Lower Grey Cloud Island. Because of potential environmental impacts mining in the backwaters might have, Aggregate Industries had filed an Environmental Impact Statement application with the City in May 2008. The City hired Barr Engineering to provide consulting services to prepare an EIS that complies with State environmental rules and the National Environmental Policy Act. The draft EIS document was scheduled to be completed in late 2012. Aggregate Industries has suspended the preparation of an EIS. If the preparation of the EIS proceeds, the Planning Commission will have the opportunity to review the EIS document in the future if Aggregate Industries decides to pursue mining in the backwaters. The City’s review of their 2019 Mining Permit application does not include any approval to mine within the backwaters or main river channel. Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 7 of 11 Reclamation Plan The 2019 Operations Plan shows most of the Nelson Mine perimeters have been reclaimed or are undisturbed buffers. In 2019, site preparation for reclamation will be approximately nine acres of land located along the east slope of the pit area. This reclamation will be prairie seeding. Approxi- mately 65 acres of land centrally located within the Nelson Mine area will be prepared for reclama- tion. Reclamation of this relatively large area will take several years to complete. Reclamation will continue in creating a large lake and peninsula centrally located within the Nelson Mine. Stabilization and establishing slopes along the perimeter of water bodies will continue. These areas will also be re-vegetated with native seed mix. Periodically, a prescribed burn might take place on previously established native prairies to control the growth of undesirable brush and tree species. Waste-sand will continue to be deposited north of the conveyor system and along the south em- bankment of the larger water body in the mined area for the next two to three years. Stabilizing the shoreline around all water bodies within the mine area will also continue. In 2010, Aggregate Industries and Great River Greening initiated the reclamation oak savanna plots within the Nelson Mine. Areas previously disturbed by mining were graded to establish rolling terrain and pot-hole lakes to mimic the original native prairie of this area. Some of the reclaimed ground was seeded with native prairie species and 60 oak saplings were planted and mulched in the oak savanna plots. Fencing was placed around the plots to delineate and deter the deer from these protected groves. In 2011, another 68 oak saplings were planted in three new groves. In 2013 and 2014, competing woody vegetation was removed from the fenced areas and fencing was repaired. In 2013 and 2015, Aggregate Industries monitored the oak groves and initiated preventive measures to ensure their establishment. These measures included watering, insecticide spraying, gopher control, and removal of competing sumac and grape ivy. An inspection of these oak sa- vanna plots in the fall of 2013 and in July 2014 found many dead oak plantings. As a condition ap- proving the annual mining permit for 2016, all the dead oak trees within the designated oak savan- nah groves must be replaced with new tree plantings and watered during dry weather conditions to promote their survival. In 2015, maintenance of the existing oak plantings continued, and prairie establishment work took place. This included prairie hand seeding bare spots on ten acres of the Interlachen Prairie. To identify mining and restorations operations between 2018 and the 2019 Operation Plans, both plans are shown on the next page. Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 8 of 11 2018 Operations Plan 2019 Operations Plan Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 9 of 11 Historic Sites and Landmarks Mining activities will continue to avoid and preserve the sensitive historic, cultural, and important natural features (remnant oak savanna) of the island. Archaeological surveys of recorded historic sites were completed in 2009 and 2010. The results of these surveys and reports concluded that Aggregate Industries can proceed with future mining operations. These sites have been marked with a 50-foot boundary around the perimeter of the Burial Mound Group 21WA9. All future mining activities will be conducted outside the designated archaeological areas. Meeting Notices A meeting notice was mailed to 18 property owners who are within a half-mile of the mine. These notices were mailed on January 16, 2019. City Department Review Aggregate Industries’ 2019 mining permit application was distributed to other City departments. No comments or recommendations were received. Recommendation It is recommended that a variance be granted to the ordinance requirement limiting mining op- erations between 6:00 a.m. to 10:00 p.m. to allow the dredge to operate 24 hours per day, seven days per week. This approval is based on the following findings of fact: A. The city has allowed the dredge to operate 24 hours per day seven days per week since 1995 when the dredge was first installed. B. Since the electric dredge has been operation, only one noise complaint was received by the city. That complaint was received in 1996. The applicant was contacted and the prob- lem was resolved in a timely manner. C. Residents are encouraged to immediately contact Aggregate Industries of any noise issues so that the problem can promptly be identified and mitigated in a timely manner. D. The variance relating to the hours of operation will be evaluated annually. It is also recommended that the 2019 Mining Permit for Aggregate Industries – Nelson Plant be approved, subject to the following conditions: 1. The provisions as stipulated in Title 3, Chapter 10 of the City’s Codes (Mining, Sand, and Gravel Operation) shall be complied with, except as modified below. 2. The applicant is responsible for removing any materials that their equipment and/or trucks may have spilled onto any public roadway. This material shall be cleaned up immediately. 3. The outer limits of their mining operations must be a minimum of 100 feet from abutting pub- lic right-of-way, private property, or any archeological sensitive area. Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 10 of 11 4. City approval of the 2019 Mining Permit does not approve their ability to mine within the required 200-foot setback from the Mississippi River, within the Mississippi River itself, or in the vicinity of archeological sensitive areas. 5. Bituminous/asphalt, concrete, and street sweepings originating within the geographical boundaries of Cottage Grove may be temporarily stockpiled on the site for processing (e.g. crushing, screening, etc.) and/or reuse. Bituminous/asphalt materials are prohibited from being buried on the premises. 6. The applicant may operate the mining operation 24 hours a day, 7 days a week. Upon noti- fication by neighboring residents that the night-time operations (i.e. between the hours of 10:00 p.m. and 6:00 a.m.) are disturbing, the applicant agrees to voluntarily cease operation during night-time hours until such time the noise source is identified and appropriate correc- tions are made. 7. Aggregate Industries must install erosion control devices at the base of any slope where erosion is evident. A drainage swale must be constructed at the base of any eroding slope to control run-off and divert it to a sedimentation basin before entering any natural drainage system. Erosion control measures must be implemented within a reasonable amount of time. 8. Archeological and landmark sites as identified in the burial mound group known as 21WA9 and the recorded Grey Cloud Townsite 21WA48 on Lower Grey Cloud Island must be protected and undisturbed. 9. All archeological, landmark sites, and existing burial mounds must be protected from being damaged or adversely impacted from vehicles or equipment traveling in the vicinity of these historic sites. 10. The applicant is responsible for obtaining all state and federal permits relating to their mining operations on Lower Grey Cloud Island. 11. The applicant’s current reclamation plan is titled “Future Land Use Plan.” The City has not provided any formal review or approval of the “Future Land Use Plan.” This concept plan is only an illustration of a development concept that the applicant and landowner have considered. The City’s approval of the 2019 Operations Plan does not guarantee approval or imply future approval of the Harbor Island Concept Plan in or the Future Land Use Plan as dated July 18, 2017 and prepared by Westwood Professional Services. 12. The Oak Savanna Reclamation Plan, Revised 9-3-2010, is still valid. If a prescribed burn is scheduled, the applicant must notify the City and property owners on Lower Grey Cloud Island a minimum of five business days before burning. A burning permit from the MN/DNR is required. All oak plantings within the designated oak savanna groves must be replaced with new oak trees and watered during dry conditions to promote their survival. 13. As the Oak Savanna Reclamation Plan is implemented, the applicant must continue to update the City on the effectiveness of the reclamation and restoration activities, particu- larly how many acorns are planted and how many oak seedlings are growing. If the sur- Planning Staff Report – Planning Case No. MP2019-002 Nelson Mining Plant – Annual Mining Permit January 28, 2019 Page 11 of 11 vival number of trees is low, then another tree planting alternative will need to be discussed. 14. Depositing fill materials within the floodway and floodway fringe (below the 700-foot mean sea level elevation) is prohibited. Prepared by: John McCool, AICP Senior Planner Attachments: 2019 Mining Permit Application Historic Summary of Mining Operations 2019 Operations Plan Map MINING OPERATIONS SUMMARY AGGREGATE INDUSTRIES – NELSON MINE SLOPE TOPSOIL TONS OF CLEARING STRIPPING MINING YEAR SEEDING PLANTINGS MATERIAL (Acres) (Acres) (Acres) RECLAMATION Control burn on approximately 14 acres of land near the 2019 Interlachen Hill area. Seeding of native grass species with 800,000 – 850,000 9 9 25 acres (approximate) 10 Proposed potential planting of diversified forbs. Initiate Siberian Elm se tree control and removal. Control burn on approximately 14 acres of land near the 2018 800,000 13 13 2.7 acres Interlachen Hill area. Additional foliar treatment of the 14 black locust root sprouts may be performed. Continued maintenance of tree groves and prairie invasive 14 acres 9 ac. re-seeding 2017 601,300 1.5 species control. Proposed 20-acre burn along eastern 9.6 2’ – 10’ depth 43 ac. Site Preparation side of lake. Foliar treatment of root sprouts where black locust trees 2016 543,486 7 – 10 7 – 10 27.5 acres 14.5 were removed. 10 acres Tree and shrub maintenance in the Oak Savanna and 2015 688,431 7 7 21.8 14 acre prescribed burn Prairie Reclamation Area. Removal of black locust trees. 42 small pin oaks, 2 large pin oaks, 2 large hackberrys, 10 2014 731,872 0 7 None 8.0 ninebark shrubs and 3 sand cherry shrubs 57.4 acres Monitor oak groves, water, insecticide spraying, gopher 2013 694,000 0 11 5.0 (approximately) control and remove sumac and grape ivy. Oak saplings monitored, protective devices maintained, 2012 783,800 0 11 22 acres 10.0 and install a gravity water system. 68 oak saplings planted and monitored, protective devices 2011 620,000 (est.) 7 10 22 acres 14.5 maintained, and a gravity water system installed. 60 oak saplings planted and several hundred acorns 2010 652,000 (actual) 6 21 22 acres 10.0 collected and sown. 2009 700,000 (est.) 0 13 12 acres Zero – Oak Savannah Plan 23.0 2008 865,911 (actual) 0 13 21 acres 100 trees 46.0 2007 1,400,000 (est.) 0 0 12.0 acres 380 trees 26.8 8.0 ac. 2006 1,700,000 (est.) 0 12.0 acres 380 trees 9.0 1.5’ – 5.0’ depths 11.0 ac. 2005 1,700,000 (est.) 0 12.0 acres 250 trees 17.6 1.5’ – 5.0’ depths 6.5 ac. 25 acres prepared for 1,250 tree seedlings 2004 1,600,000 (est.) 0 6.5 1.’-5.0’ depths reclamations (minimum height of 24”) 25 acres prepared for 6.5 ac. 1,250 tree seedlings 2003 1,600,000 (est.) 0 14.0 reclamation; (3.0’ avg. depth) (minimum height of 24”) 2 acres for topsoil and 7.4 ac. 1,250 tree seedlings 2002 1,600,000 (est.) 0 13 acres 10-13 seeding (2.5’ avg. depth) (minimum height of 24”) \\\\cocg-fs1\\groups\\CITYFILES\\19 CITYFILES\\002MP Aggregate Industries 2019-01-28\\MP19-002 Agg Ind History Table 2019-01-26.doc