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10.a Martin Marietta AOP 2023 - CC Packet1 | P a g e Date of Meeting: March 21, 2023 To: Mayor and City Council From: T.J. Hofer, Consultant City Planner Re: Annual Operators Permit (AOP) for Martin Marietta Mine Applicant: Christina Morrison Tiller Corporation, a Martin Marietta Materials, Inc. Company Zoning: Rural Residential - General (RR-G) Mining Overlay Owner: Christina Morrison Tiller Corporation, a Martin Marietta Materials, Inc. Company Future Land Use Mining Location: 16315 209th Street North PID 1903219220004 & 1903219220008 Review Deadline: April 2, 2023 BACKGROUND Tiller Corporation, a Martin Marietta Materials, Inc. Company, has applied for its 2023 Annual Operating Permit (AOP) for their existing sand and gravel mining operation located on Manning Avenue near 225th Street in Scandia. The site has been actively mined since 1966, and currently operates under Conditional Use Permits (CUPs) granted by the City on May 20, 2008. The Tiller mine site previously operated under a CUP issued by Washington County when the County exercised land use authority within New Scandia Township. Permitted activities included the mining and processing of aggregate, the production of hot-mix asphalt, and the recycling of concrete and asphalt products. 2 | P a g e The City’s Mining Ordinance specifies an AOP cycle that coincides with the active mining season. Applications are due by January 31 each year, to enable permits to be approved before the start of the mining season later in that year. The applications for the Scandia Mine Site since 2010 have included both the Tiller site and the adjacent former Dresel Mine to the southeast. Tiller purchased the Dresel site in 2009 and operates both sites. The City issued a CUP for mining and processing at the Dresel site on May 20, 2008. As the owner of both sites, Tiller is to comply with the conditions of both the Tiller and Dresel CUPs. Issues and compliance with each are discussed in this report. EVALUATION OF REQUEST The Applicant is requesting an Annual Operating Permit (AOP) for a mining and processing operation. The permit requirements are governed by Ordinance No. 103, Regulation of Mining and Related Activities, Chapter 4 of the Development Code. The Ordinance requires review of the following items for the AOP: 1. The operating conditions of the previous year and conditions required by the CUPs for the Tiller and Dresel sites. 2. Proposed operating conditions and any variation from the previous year. 3. Results of the annual inspection by the City. Conditional Use Permit Tiller Mine Site The City of Scandia approved a Conditional Use Permit for sand and gravel mining and processing at the Scandia Mine site for Tiller Corporation on May 20, 2008. The conditions included the items noted in the table that follows. Tiller’s performance is indicated in the table on the following pages. There were no issues identified in 2022 for the Tiller Mine site. Condition Deadline Specified in CUP Notes 1. Comply with CUP Ongoing In process--monitored by City staff and consultants 2. Comply with Rules and Regulations Ongoing In process--monitored by City staff and consultants 4. Permits from CMSCWD None specified CMSCWD Permit 08-003 for the Tiller mine remains in effect. The Watershed District Permit, P08-003, was revised in 3 | P a g e Condition Deadline Specified in CUP Notes 2019 to align the permit with the City’s annual review process and eliminate a 5- year term on the permit. The revisions to the permit were approved by District Managers during their February 13, 2019, Regular Meeting. 5. Monitoring Wells July 20, 2008 Three required monitoring wells were installed in 2008. One well was taken out of service and sealed in 2011 to accommodate reclamation activities (MW- 2). Monitoring results for the two active wells in 2022 were provided with the AOP application and reviewed by LRE Water, the City’s groundwater consultant. 6. Ground Water Monitoring July 20, 2008 The Ground Water Monitoring Plan was approved in the fall of 2008 and revised in 2013. The plan is on file with the City. In May 2022, Martin Marietta received authorization from MN DNR to increase its annual water appropriation from 20 MGY to 30 MGY for aggregate production and dust control. With the increased water appropriation, a short-term monitoring plan was developed and implemented to help evaluate aquifer recovery to pre-pumping water levels following pumping during periods of high use. Data collected in accordance with the short-term monitoring plan was submitted to the City in August 2022. 7. Excavation below water table May not begin August 20, 2008 Excavation into the water table began in 2009. The CUP permits mining into groundwater table to a depth of 50 feet. Excavation into the groundwater table has occurred as follows: 2013 — to a depth of 15 to 20 feet 2014 — no mining into groundwater table 4 | P a g e Condition Deadline Specified in CUP Notes 2015 — no mining into groundwater table 2016 — to a depth of 15 to 20 feet 2017 — no mining into groundwater table 2018 — no mining into groundwater table 2019 — to a depth of 15 feet 2020 — to a depth of 17 feet 2021 — no mining into groundwater table 2022 — no mining into groundwater table Water level data is collected on an ongoing basis and submitted to the City. Water level data was submitted with the AOP application. The review from LRE Water, water quality consultant for the City of Scandia, is discussed in this report in the Groundwater Monitoring section. 8. Production Well Records July 20, 2008 Production well records are being kept by Tiller and are available to the City. Water pumped at the site in 2022 was 5,810,150 gallons. The DNR Water Appropriation Permit for the site allows up to 30 million gallons to be used each year.28 MGY are approved for washing and 2 MGY are approved for dust control. 9. Ground Water Analysis - DRO (Diesel Range Organics) and GRO None specified Groundwater samples were analyzed for DRO. No gasoline is stored on site. If gasoline storage is added, GRO will be analyzed. Monitoring results were included with the application and reviewed by LRE Water. No DRO were detected in the samples in 2022. 10. Map of Index Well Sites July 20, 2008 Map was provided to the City on August 28, 2008. 5 | P a g e Condition Deadline Specified in CUP Notes 11. Asphalt Plant Setback from Lake Ongoing Setback has been maintained, as required by the CUP. 12. Lake Depth Ongoing Application indicates that the depth of excavation will not exceed fifty (50) feet below the water table, as per the CUP. Excavation depth to date has been less than 50 feet into the groundwater table through 2022. 13. Truck Signage and Roadway Cleaning July 20, 2008 Washington County has posted signs on Lofton and Manning Avenues per their County requirements. Tiller has posted signs on 218th Street and Lofton Avenue to restrict trucks from using 228th Street per City of Scandia requirements. During construction season, a “No Engine Breaking" sign is now being placed on Manning Trail North near the entrance to the site to address concerns of engine breaking on the road. Signage was in place during the City site visit in 2022. 14. Lofton/ Highway 97 Intersection July 20, 2008 Tiller restricts importing add-rock from Lofton Avenue during non-daylight hours per the CUP requirements. 15. 228th Street Signage July 20, 2008 Signage is posted at the Lofton Avenue North exit that restricts trucks from using 228th Street. 16-19. Updated Reclamation Plan July 20, 2008 Included in application materials; discussed below. 20. Letter of Credit/Security Due before AOP approval The financial guarantees are current. 21. AOP Application Submittal January 31, annually Application was submitted on January 31, 2021, and determined to be complete. 6 | P a g e Dresel Mine The City of Scandia approved a Conditional Use Permit for sand and gravel mining and processing for Dresel Contracting, Inc. on May 20, 2008. Tiller Corporation now owns and operates this site, and therefore must also comply with the conditions of the Dresel CUP. There were no issues identified in 2022 on the Dresel Mine site. Condition Deadline Specified in CUP Notes 1. Comply with CUP Ongoing In process--monitored by City staff and consultants 3. Comply with Rules and Regulations Ongoing In process--monitored by City staff and consultants 4. Permits from CMSCWD None specified CMSCWD Permit 08-003 for the Tiller mine remains in effect. The Watershed District Permit, P08-003, was revised in 2019 to align the permit with the City’s annual review process and eliminate a 5- year term on the permit. The revisions to the permit were approved by District Managers during their February 13, 2019 Regular Meeting. 5. Monitoring Wells July 20, 2008 Installed in May 2008. Groundwater Plan was updated to reflect changes to monitoring well MW-2 in 2013. The site complied with the plan in 2022. 6. Revise Proposed Conditions Plan Pit Elevations Monitoring July 20, 2008 The City previously approved a maximum mining depth of 922 feet AMSL at the Dresel site, ensuring three feet of separation between the floor of the mine and the water table surface during high water table conditions, based on monitoring results. LRE Water, water quality consultant for the City of Scandia, reviewed the submitted data and made recommendations which are included in this report under the Groundwater Monitoring section. 7 | P a g e Condition Deadline Specified in CUP Notes 7. Ground Water Monitoring Plan July 20, 2008 Approved in October 2008 and on file at the City. 8. Revise Site Plan include Index Wells July 20, 2008 Provided to City on August 28, 2008. 9. Identify Bench Mark Elevation July 20, 2008 Established at top of Well Casing MW-1. 10. Ground Water Analysis - DRO and GRO None specified Samples are analyzed for DRO when mining activity is occurring. No gasoline is stored on site. If gasoline storage is added, GRO will be analyzed. No DRO or other contaminants were detected in 2022 monitoring at the Dresel site. 11. Signage on 218th and Roadway Cleaning Ongoing Signage was installed and meets the CUP requirements; signage was in place during the 2022 site visit. 12. Truck Cleaning Ongoing Trucks must meet requirements for cleaning, per CUP. No issues were identified during the 2022 site visit. 13. Delineate Northern Wetland None specified Wetland report and delineation completed. Buffer marked by September 15, 2008. Complaint received regarding encroachment into a wetland in late 2014. Mitigation and replacement plan were completed and approved by TEP panel and wetland credits were successfully withdrawn from the BWSR Wetland Bank in 2016. 14-17. Updated Reclamation Plan July 20, 2008 The Reclamation Plan was previously revised as part of a combined Reclamation Plan submitted for the Tiller Site. 18. Letter of Credit/Security Before AOP approval Financial guarantees are current. 8 | P a g e Condition Deadline Specified in CUP Notes 21. AOP Application Submittal January 31, annually Application was submitted on January 31, 2021, and determined to be complete. Proposed Operating Conditions, Deviations from Previous Year, and Ordinance Requirements Site Operations - Background Information The Tiller mine site includes several parcels, as indicated on the Site Plan. Excavation activities in 2010-2011 removed material between the Tiller site and the former Dresel Mine site, merging the two sites into one. Marietta mined only the Tiller site in 2022. No mining activities occurred on the Dresel site in 2022. The mining operation includes removal of overburden; excavation of sand and gravel; crushing, washing, screening, stockpiling of sand and gravel; recycling of concrete and asphalt products; the production of hot-mix asphalt; and reclamation activities. The overburden is removed from areas to be mined and stockpiled on the site for use in reclamation activities. The operator brings portable crushing, washing, and screening plants to the site periodically and these are used to process and stockpile materials. The operator produces and sells asphalt throughout the construction season and delivers add-rock materials to sites as needed to produce the required mixes and materials. Mining into the groundwater table began at the site in 2009. This activity has been described in the previous mining plans for this site and was evaluated in the Environmental Assessment Worksheets completed for the Tiller site in 1987 and 1999. The CUP allows mining into the groundwater to a maximum depth of 50 feet. Mining into the groundwater table occurred in 2013, 2016, 2019, and 2020 to a depth of 15-20 feet. Mining into the groundwater table did not occur in 2014, 2015, 217, 2018, 2021, or 2022. The asphalt plant at the site is equipped with a bag-house air pollutant collection device and operates under a Minnesota Pollution Control Agency (MPCA) Air Emissions Permit. Storage tanks at the site (for fuel and asphalt cement) are regulated by the MPCA. The main access routes to and from the site are Manning Avenue (County Road 15) and Lofton Avenue (County Road 1). Both Manning and Lofton are paved. The haul road from Manning Avenue is paved through the site to the hot-mix asphalt plant and loading area. 9 | P a g e Annual Activity The application submission included the data required by the ordinance regarding annual activity on the site, as follows: 2021 2022 Amount of material removed from the site (in tons) 430,000 378,000 Amount of add-rock brought onto site (in tons) 77,000 92,000 Recycled asphalt and concrete brought to the site (in tons) 35,000 41,000 Average number of trips to and from the site each day (in trips/day) 225 214 The application anticipates that mining and processing will continue at the site in 2023. The level of activity will depend on market demand for the site products. The Site Plan identifies the Potential Mining Areas for 2023, which are within the approved mining limits. Potential areas for reclamation are also identified on the Site Plan; these are discussed later in this report. Ground Water Monitoring The approved Groundwater Monitoring Plan for the site is on file with the City. The City’s groundwater consultant, LRE Water, reviews the groundwater monitoring results each year for the AOP and provides comments to the City. LRE Water did not note any concerns with the 2023 application as it relates to groundwater quality and quantity. Below are the 2023 Groundwater Monitoring Data Review Comments from LRE Water: • The 2022 groundwater monitoring was completed in accordance with the approved monitoring plan. • Groundwater samples were collected from the monitoring well and piezometers, pond, production well and potable well on 9/14/22. These were analyzed for Diesel Range Organics (DRO) as outlined in the monitoring plan. DRO was not detected above the method detection limit in any of the samples. These results and the other groundwater chemistry results indicate no groundwater quality concerns. • The groundwater flow direction across the site is generally to the north and is consistent with previous submittals. 10 | P a g e • From October 2021 through October 2022, groundwater levels across the site declined from approximately 1.4 feet in piezometer PZ-6 to approximately 3.6 feet in monitoring well MW-1. The most recent levels measured on October 2022 are still approximately 4 to 5 feet higher than the lowest levels measured in 2010. The decrease in water levels observed in since the fall of 2020 is the result of local and regional changes in precipitation, and unrelated to mining operations and pumping by the production well. This is shown by the annual precipitation data that is plotted with water levels on the attached hydrograph (Figure 1). The water levels and precipitation show similar trends over time. Figure 1 is included in the attachments for this staff report. In 2022, the applicant received an increase from the MNDNR to allow the groundwater appropriations to be increased from 20 million galls per year (MGY) to 30 MGY. LRE Water noted the following regarding aquifer pumping tests that were performed: The 2022 AOP required a short-term monitoring plan be developed and implemented this year to evaluate potential for regional impacts from groundwater pumping associated with aggregate washing at the Site. The plan was in response to the MN DNR’s approval of the increase in groundwater appropriations from the Site production well from 20 million gallons per year (MGY) to 30 MGY on May 26, 2022. The plan was implemented by Martin Marietta with assistance from their consultant, Sunde Engineering. The plan included the following activities: A pumping test that was completed during a period of highest production well use. The production well was pumped at approximately 475 to 500 gallons per minute (gpm) beginning on 6/13/22. Water levels were monitored in the production well, PZ-3 and the staff gage in the pond using pressure transducers and data loggers, and measured manually periodically. Monitoring continued through 7/1/22. (Note that the Production Well had to be shut off periodically when the sedimentation basins were full; however, this did not interfere with the test and results.) Summary of results: The results from the plan provided the information necessary to evaluate the aquifer’s response to pumping at the site at the highest pumping demand, and assess any regional impacts. 11 | P a g e Water levels in the production well declined approximately 5 to 7 feet when pumping for approximately 12 hours at rates of approximately 475 to 500 gpm. When the pump shut off, water levels recovered to their pre-pumping levels quickly, and before the next pumping cycle began. Groundwater levels at PZ-3 (located approximately 300 feet from the production well) appeared to have less than 0.5 feet of decline, if any, during the pumping phases. Water levels in the pond were not influenced by pumping. The observed groundwater level declines and rate of groundwater level recovery indicate a very prolific aquifer. Based on the information to date, there no concerns to the resource when pumping at the rates necessary to meet the facility’s peak demands under normal operations. The data files and data plots from the test are not included in this email; however, they are on file with the City or can be obtained from LRE Water or Martin Marietta. Recommendations provided by LRE Water include the following: • Continue the annual sampling for water quality parameters as outlined in the monitoring plan. • Continue to map the area(s) of excavation into the water table. Operating Conditions - Mining Ordinance Requirements, Section 7 1. Setbacks The AOP application indicates that the minimum setbacks are maintained as follows: • 50 feet from the adjoining property line • 200 feet from any existing occupied structure not owned by operator or owner • 100 feet from residential property subdivided into lots of 5 acres or less • 100 feet from any road right-of-way The setbacks meet the requirements of Chapter 154 7.1 Setbacks. The City’s 2022 inspection indicated that the setbacks were maintained and still meet City requirements. 12 | P a g e 2. Fencing The application indicates that the majority of the site is fenced with 3-strand wire fencing, except where prohibited due to topography, heavy vegetation and wetlands. There are locking metal gates at both entrances. The fencing meets the intent of the City’s Ordinance. City staff reviewed the fencing during the site visit in 2022 and verified that it meets the requirements of the Ordinance and CUP. 3. Hours of Operation The site is operated from 7 am to 7 pm Monday through Friday, except holidays. The applicant is required to obtain the City’s permission for any extended hours in accordance with procedures set in Chapter 154, Section 7.3: “(3) Hours of Operation. Those portions of the mining operation consisting of excavating, stockpiling, processing, or hauling shall be conducted only between the hours of 7:00 a.m. and 7:00 p.m., Monday through Friday, unless other hours or days of operation are specifically authorized by the City.” Tiller requested, and the City approved, eight extended hours requests in 2022. The requests were for improvement projects on CSAH roads and county roads through Washington County. In 2021, there were four requests granted. Requests for extended hours vary from year to year, depending on projects and weather. 4. Screening The mine is screened from surrounding areas by berms, wooded areas, and farm fields. A number of trees have been planted over the years of the mining operation to augment the screening. Processing and stockpiling operations are conducted in recessed portions of the site to minimize visibility. 5. Dust Control Major haul roads are hard-surfaced or covered with asphalt millings as dust control measures. The application indicated that Tiller used a water truck to control dust on unpaved portions of the site, and calcium chloride was applied to minimize dust generated by trucking activity. These actions were first implemented in 2019, and have been continued as needed since then. Tiller plans to continue such practices as needed in 2023. The CUP does not require additional dust control efforts. 6. Noise The Applicant must comply with all Federal, State, and City noise standards. 7. Depth of Excavation 13 | P a g e The CUP requires that the depth of excavation shall not exceed fifty feet below the water table (865 feet above mean sea level) on the Scandia Mine site and may not be lower than 922 feet above mean sea level (amsl) on the former Dresel Mine site. In 2022, excavation into the groundwater table did not occur. Excavation into the groundwater table is not anticipated in 2023. If excavation into the groundwater table occurs in 2023, it would occur within the 2023 Potential Mining Area as depicted on their submitted site plan. 8. Site Clearance Site clearing activities did not occur in 2022. If clearing activity occurs, it will occur within the 2023 Potential Mining Areas as depicted on Figure 2, Site Plan. 9. Appearance/Condition The City’s site inspection in 2022 confirmed that the site and facilities are maintained in a neat condition. 10. Sanitary Facilities The application indicates that the site is served by individual sanitary facilities that meet the requirements of the City’s Ordinance and the Mine Safety and Health Administration. City staff inspection confirmed that the City’s requirements were met in 2022. 11. Waste Disposal The application indicates that waste generated by the operation is disposed of in accordance with Federal, State, and City requirements. The City’s site visit in 2022 confirmed that the Applicant is meeting the requirements of the CUP. 12. Water Quality Monitoring Plan The CUP required that Tiller Corporation complete a plan for groundwater monitoring within 60 days of approval of the 2008 CUP (July 20, 2008). The approved groundwater monitoring plan was completed and is on file at the City. Tiller submitted monitoring results for 2022 with its application for the 2023 AOP. LRE Water reviewed the groundwater monitoring activities and found that no DRO (diesel range organics) were detected in the samples in 2022. 13. Fuel and Chemical Storage The application describes fuel and chemical storage at the site. The applicant notes that these materials are stored in accordance with Federal and State standards and County requirements. On-site fuel storage consists of a 200-gallon above-ground storage tank which is located within a steel secondary containment area and a 1,000-gallon above- ground double-walled tank located next to the standby electrical generator. When 14 | P a g e processing and/or reclamation crews are present, an additional 1,000-gallon double- walled tank is brought to the site and used to fuel the respective equipment. All asphalt cement storage tanks are above-ground. These tanks consist of two 40,000 gallon tanks and two 32,000 gallon tanks. There is also a 20,000 gallon above-ground used oil storage tank. The used oil is utilized as an alternative fuel supply for the asphalt plant. All tanks containing asphalt cement and used oil are located within a concrete secondary containment area. All tanks are registered with MPCA’s Storage Tank Program. MPCA Site ID 51999 is for the asphalt plant and MPCA Site ID 55016 is for the sand and gravel operation. City staff reviewed the facilities with Tiller staff at the 2022 site visit. Small amounts of chemicals utilized by the QM Lab are regulated by Washington County under the United States Environmental Protection Agency (EPA) rules. EPA ID Number MND 981 953 417 has been issued for the site which is classified as a Very Small Quantity Generator. 14. Contingency Response Plan The application indicates that the site operates under a Spill Prevention, Control and Countermeasure Plan (SPCC) Plan that was submitted and is on file at the City. The applicant notes that the mine operator will comply with other such reasonable requirements that the City may find necessary to adopt for the protection of health, safety and welfare and/or prevention of nuisance. 15. Processing The CUP application describes the operation of permanent processing equipment on the site and indicates that the equipment is operated in accordance with Federal, State, and City air quality, water quality, and noise standards. The equipment is screened from view from other properties and adjacent roads. The CUP requires that the asphalt plant and related structures be set back at least 100 feet from the shore of the proposed lake on the site. The site visit in 2022 verified that the processing facilities meet the setback requirements of the CUP, and no violations of permits were reported in 2022. 16. Recycling Recycling at the site is permitted by Chapter 154. Asphalt production used approximately 52,000 tons of recycled asphalt products (RAP) in 2022. 41,000 tons of RAP was brought into the site in 2022; at year-end there were 48,000 tons of RAP on the site. Processed RAP is used in asphalt production and recycled concrete is sold in various aggregate products. A Solid Waste Storage Facility license that authorizes the storage of unprocessed concrete, concrete products, and brick and a Recycling Facility license that authorizes the storage and processing of recycled asphalt products are issued to Tiller by Washington 15 | P a g e County. General and Specific Conditions are established for each license and are reviewed on an annual basis and may include an annual inspection completed by the County. 17. Trucking Operations The application indicates that the site has access to County Road 15 (Manning Trail N.), County Road 91 (Lofton Avenue N.), and 218th Street North. These are hard-surfaced roads. The operator reported that the average number of trucks traveling to and from the site per day in 2022 was approximately 214 trucks per day. The proposed conditions for the 2023 AOP are the same as those included in previous AOPs, which require that Tiller inform all contractors about the following requirements related to trucking operations, and monitor compliance with the requirements by all of its contractors: • Engine braking is prohibited in Scandia • Lofton Avenue is restricted to daytime use only • Loads are required to be covered Last year, a “No Engine Breaking” sign was installed on the northbound lane of Manning Trail North near the entrance to the site to alert truck drivers entering the site. This sign will be up during construction season and removed during the off-season. 18. Asphalt Plant The site operates a permanent hot-mix asphalt plant that was in operation at the time the City adopted its mining ordinance. The plant operates under an air quality permit issued by the MPCA and must meet federal, state, and city air, water, and noise standards. The City received no complaints regarding the operation of the asphalt plant in 2022. Reclamation Plan - Mining Ordinance Requirements, Section 8 Section 8.2 of Chapter 154 requires the “restoration shall proceed concurrently and proportional to actual mining operations and will be subject to review and approval at each annual inspection and the end of the permit period." This section is included in the ordinance to ensure that large areas of the site are not left in an unreclaimed state, encouraging erosion, dust, and weed establishment. The mining operation is making an ongoing investment in reclamation, to avoid potential problems that may occur at the end of the mining operation if a large investment is needed in reclamation, and the applicant’s resources are limited at that point, or the applicant abandons the site. Section 8.4 of the City’s Mining ordinance requires the following for reclamation areas: • All banks must be graded or backfilled 16 | P a g e • Graded or backfilled areas shall be surfaced with soil of a quality at least equal to the topsoil of areas immediately surrounding, to a depth of at least four inches • The topsoil shall be planted with trees, shrubs, legumes, or grasses • Slopes shall not be steeper than 4:1 Reclamation activities in 2022 included the placement of overburden and suitable fill material in the west half of the mining area, north of the Tiller Mine/Dresel Mine common mining border. The completed and ongoing reclamation areas are indicated on Figure 2, Site Plan. Ongoing reclamation activities are anticipated north and south of the Tiller Mine/Dresel Mine common mining border and primarily along the east half of the mining area during 2023. These areas are shown on Figure 2, Site Plan as “2023 Potential Reclamation Activity”. Some of the areas shown as potential reclamation will also see active mining during 2023. Once mining is complete, reclamation may advance into these areas during 2023. Reclamation completed meets the requirement of the CUP. Comments Watershed District Comments The Carnelian-Marine-St. Croix Watershed District reviewed the 2022 AOP application and has no concerns. The CMSCWD permit runs until completion of mine activities, with some exceptions as identified in the permit. The permit requires the applicant to complete the following activities on an annual basis: 1. Provide a copy of the annual AOP performance submittals for the City of Scandia, to the watershed for review. 2. Coordinate a site inspection by the CMSCWD Administrator 3. Reimburse CMSCWD for all expenses associated with implementation of the permit. City Engineer The City Engineer did not provide comment. Public Works Director The Public Works Director did not provide comment. Site Inspection City staff completed a site visit to the Tiller Corporation Scandia Mining Operation on December 8, 2022, including documenting conditions on the site. The site visit reviewed activities and site conditions based on the CUP and 2022 AOP, and discussed expected activity in 2023. 17 | P a g e ACTION REQUESTED The City Council can: 1. Approve the AOP 2. Approve the AOP with conditions 3. Deny the application if it is found that the request is not consistent with the Comprehensive Plan, CUP, AOP Criteria, and Mining Ordinance, and is not in the best interest of the community 4. Table the request if the Council needs additional information to make its decision. STAFF RECOMMENDATION Staff recommends approval of the Tiller Corporation 2023 AOP for sand and gravel mining and related processing at the Scandia Mine, 22303 Manning Avenue North, with the following conditions: 1. The applicant shall comply with the conditions of the Conditional Use Permit for sand and gravel mining and processing at the Scandia Mine site approved on May 20, 2008. 2. The applicant shall comply with site operation hours of 7 a.m. to 7 p.m. Monday through Friday, except holidays, unless the applicant requests and receives the City’s permission for extended hours in accordance with procedures set forth in Chapter 154. 3. The applicant shall continue to observe groundwater levels during the year. If levels continue to rise, there is the potential for the water table surface to be above the depth of the excavation and outside of the limits of the proposed lake. If this occurs, maps submitted for the 2023 AOP shall identify the general areas where excavation depth is below the water table. 4. The applicant shall provide the approximate depth of the excavation below the water table in future annual reports to confirm the excavation did not go below the 865.87 feet amsl threshold. 5. The applicant shall continue to provide the production well records for the site to the City so the pumping records can be compared to past and future groundwater level trends at the site. The applicant should measure the water level in the production well under non- pumping conditions during monitoring periods. 6. Requests for operating hours or haul routes outside those specified in the Conditional Use Permit shall be accompanied by a proposed truck haul route for approval by staff. 18 | P a g e 7. The applicant shall inform its contractors about the following requirements related to trucking operations, and monitor compliance with the requirements by all of its contractors: • Engine braking is prohibited in Scandia • Lofton Avenue is restricted to daytime use only • Haul loads are required to be covered 8. The applicant shall regularly monitor the entrances and exits to the site, and work with their hauling contractors and truck drivers to maintain compliance with traffic laws. 9. The reclamation activities shall meet the requirements of the Conditional Use Permit, including soil and planting requirements. 10. If the applicant has knowledge that a crash or traffic violation occurs involving a truck hauling for Tiller, Tiller shall contact the City to report the incident immediately. The applicant shall report actions it will take to respond to the incident. 11. The applicant shall pay all fees and escrows associated with this application. 12. This Annual Operating Permit shall expire on March 31, 2024. Attachments A. Resolution 03-21-23-05 Approving the AOP for Martin Marietta Mine B. Location Map C. Application D. Applicant’s Narrative E. Comments from David Hume of LRE Water CITY OF SCANDIA, MINNESOTA RESOLUTION 03-21-23-05 RESOLUTION APPROVING THE 2023 ANNUAL OPERATING PERMIT FOR THE SAND AND GRAVEL MINE AND PROCESSING FACILITY AT THE SCANDIA MINE SITE WHEREAS, Tiller Corporation, a Martin Marietta Materials, Inc. Company, operates a sand and gravel mining and processing operation and asphalt hot-mix plant located on approximately 435 acres at Manning Avenue North, on property legally described as: See Attachment A WHEREAS, the site has been actively mined since 1966, and has operated under a previous Conditional Use Permit granted by Washington County, when the County exercised land use authority within New Scandia Township. Permitted activities include the mining and processing of aggregate, the production of hot-mix asphalt, and the recycling of concrete and asphalt products; and WHEREAS, an Environmental Assessment Worksheet (EAW) was prepared for this mining facility in 1987, a second EAW was completed in 1999 for a proposed expansion of the facility; and WHEREAS, the scope of operations and mining limits proposed in the current permit application to the City are consistent with the scope of the operations and mining limits reviewed in the 1999 EAW; and WHEREAS, Ordinance No. 103, Chapter 4 of the Development Code of the City of Scandia, Minnesota, adopted September 20, 2022 (hereinafter referred to as “the ordinance”) replaced the requirements of the ordinances adopted by the City of Scandia on August 28, 2007, which replaced the ordinances adopted by Washington County and the former New Scandia Township and required the issuance of a new Conditional Use Permit and Annual Operating Permits for continued operation of existing mining operations; and WHEREAS, the City approved a Conditional Use Permit for the mining and processing operations on May 20, 2008; and WHEREAS, Tiller Corporation, Inc. submitted an application for an Annual Operating Permit to the City of Scandia, which was found to be complete for review January 31, 2023; and WHEREAS, the Scandia City Council reviewed the application at its regular meeting on March 21, 2023. NOW, THEREFORE, BE IT HEREBY RESOLVED BY THE CITY COUNCIL OF THE CITY OF SCANDIA, WASHINGTON COUNTY, MINNESOTA, that the Annual Operating Permit for Tiller Corporation for a sand and gravel mine and processing facility at the Scandia mine site is approved, subject to the following conditions: 1. The applicant shall comply with the conditions of the Conditional Use Permit for sand and gravel mining and processing at the Scandia Mine site approved on May 20, 2008. 2. The applicant shall comply with site operation hours of 7 a.m. to 7 p.m. Monday through Friday, except holidays, unless the applicant requests and receives the City’s permission for extended hours in accordance with procedures set forth in Chapter 154. 3. The applicant shall continue to observe groundwater levels during the year. If levels continue to rise, there is the potential for the water table surface to be above the depth of the excavation and outside of the limits of the proposed lake. If this occurs, maps submitted for the 2023 AOP shall identify the general areas where excavation depth is below the water table. 4. The applicant shall provide the approximate depth of the excavation below the water table in future annual reports to confirm the excavation did not go below the 865.87 feet amsl threshold. 5. The applicant shall continue to provide the production well records for the site to the City so the pumping records can be compared to past and future groundwater level trends at the site. The applicant should measure the water level in the production well under non-pumping conditions during monitoring periods. 6. Requests for operating hours or haul routes outside those specified in the Conditional Use Permit shall be accompanied by a proposed truck haul route for approval by staff. 7. The applicant shall inform its contractors about the following requirements related to trucking operations, and monitor compliance with the requirements by all of its contractors: • Engine braking is prohibited in Scandia • Lofton Avenue is restricted to daytime use only • Haul loads are required to be covered 8. The applicant shall regularly monitor the entrances and exits to the site, and work with their hauling contractors and truck drivers to maintain compliance with traffic laws. 9. The reclamation activities shall meet the requirements of the Conditional Use Permit, including soil and planting requirements. 10. If the applicant has knowledge that a crash or traffic violation occurs involving a truck hauling for Tiller, Tiller shall contact the City to report the incident immediately. The applicant shall report actions it will take to respond to the incident. 11. The applicant shall pay all fees and escrows associated with this application. 12. This Annual Operating Permit shall expire on March 31, 2024. FURTHER, BE IT RESOLVED, that any significant variation from these plans and conditions of approval shall require an application to amend this Annual Operating Permit. Adopted by the Scandia City Council this 21st day of March, 2023. Christine Maefsky, Mayor ATTEST: Anne Hurlburt, Interim City Administrator Attachment A Section 1. The Southeast 1/4 of Section 7, in Township 32 North, of Range 20 West; and that part of the Southwest 1/4 of the Southwest 1/4 of Section 8, in Township 32 North, of Range 20 West, described as follows: Commencing at a point in the North line of said Southwest 1/4 of the Southwest 1/4 of said Section 8, 22 rods East of the Northwest corner thereof, thence West along said North line to the Northwest corner of said Southwest 1/4 of the Southwest 1/4, thence South along the West line of said Southwest 1/4 of the Southwest 1/4 to the Southwest corner thereof, thence East along the South line of said Southwest 1/4 of the Southwest 1/4 a distance of 42 rods to a point, thence Northwesterly in a straight line to the point of beginning; and also a strip of land 2 rods wide on the North side of said Southwest 1/4 of the Southwest 1/4, commencing 22 rods East of the Northwest corner thereof and extending to the Northeast corner thereof. That part of the South Half of the Northeast Quarter of Section 7, Township 32 North, Range 20 West, Washington County, Minnesota, described as follows: Commencing at the Northwest corner of said South Half; thence Easterly along the North line of said South Half a distance of 1223.40 feet to the point of beginning; thence Southerly, parallel with the West line of said South Half, a distance of 1319.60 feet to the South line of said South Half; thence Easterly along said South line a distance of 1423.65 feet to the Southeast corner of said South Half; thence Northerly along the East line of said South Half a distance of 1317.76 feet to the Northeast corner of said South Half; thence Westerly along the North line of said South Half a distance of 1422.96 feet to the point of beginning. Subject to 228th Street North along North line. Section 2. That part of the Southeast Quarter of the Southwest Quarter and of the South Half of the Northeast Quarter of the Southwest Quarter of Section 7, Township 32, Range 20, Washington County, Minnesota lying easterly of the centerline of County Road 15A as said centerline is described in Book 312 of Deeds on pages 19 and 20. Subject to County Road 15A. Subject to easements of record. Section 3. The North One-Half of the Southwest Quarter (N 1/2 of SW 1/4) and the Southeast Quarter of the Northwest Quarter (SE 1/4 of NW 1/4) all in Section 8, Township 32, Range 20. Except: All that part of the Northeast Quarter of the Southwest Quarter (NE 1/4 of SW 1/4) of Section 8, Township 32, Range 20, Washington County, Minnesota lying East of the centerline of County State Aid Highway No. 1 (Lofton Avenue). Section 4. That part of the Southeast Quarter of the Southwest Quarter (SE 1/4 of SW 1/4) of Section 8, Township 32, Range 20 lying West of the public highway as the same now runs over and across said tract, except the North 2 rods thereof; and that part of the Southwest Quarter of the Southwest Quarter (SW 1/4 of SW 1/4) of Section 8, Township 32, Range 20 described as follows, to wit: Beginning 22 rods East of the Northwest corner of said Southwest Quarter of Southwest Quarter (SW 1/4 of SW 1/4); thence Southeasterly in a straight line to a point 42 rods East of the Southwest corner of said Southwest Quarter of Southwest Quarter (SW 1/4 of SW 1/4); thence East to the Southeast corner of said Southwest Quarter of Southwest Quarter (SW 1/4 of SW 1/4 ), thence North to the Northeast corner of said Southwest Quarter of Southwest Quarter (SW 1/4 of SW 1/4), thence West to the point of beginning, except the North 2 rods thereof said tract. Except: That part of the North 320.00 feet of the South 620.00 of the Southeast Quarter of the Southwest Quarter of Section 8, Township 32, Range 20, Washington County, Minnesota, lying Westerly of the center line of County State Aid Highway No. 1, as the same is now laid out and traveled, said center line is described as follows: Beginning at a point on the South line thereof distant 37.30 feet Westerly of the Southeast comer thereof (for the purposes of this description, the South line of said Southeast Quarter of the Southwest Quarter is assumed to bear South 89 degrees 38 minutes 18 seconds West); thence Northerly along a curve concave to the West, having a radius of 2864.81 feet and a central angle of 7 degrees 12 minutes 48 seconds, a distance of 360.67 feet, the chord of said curve bears North 14 degrees 39 minutes 10 seconds West; thence North 18 degrees 15 minutes 34 seconds West, tangent to said curve, a distance of 282.59 feet; thence Northerly along a tangential curve, concave to the East, having a radius of 1980.97 feet and a central angle of 20 degrees 29 minutes 54 seconds, a distance of 708.72 feet to the North line of said Southeast Quarter of the Southwest Quarter, and there terminating. And lying Easterly of the following described line: Commencing at the Southwest corner of said Section 8; thence Easterly along the South line of said Section 8, a distance of 1714.61 feet to the point of beginning of the line to be described; thence Northeasterly, deflecting to the left 83 degrees 54 minutes 52 seconds, a distance of 623.51 feet to the North line of the South 620.00 feet of said Southeast Quarter of the Southwest Quarter, and there terminating. Also except: That part of the Southeast Quarter of the Southwest Quarter of Section 8, Township 32 N, Range 20 W, described as follows: Commencing at the Southwest corner of said Section 8, thence Easterly along the South line of Section 8 a distance of 1714.61 feet which is the point of beginning of this description; thence Northeasterly deflecting to the left 83 degrees 54 minutes 52 seconds a distance of 301.70 feet to the North line of the South 100 feet of the Southeast Quarter of the Southwest Quarter of Section 8; thence Easterly along said North line a distance of 757 feet, more or less, to the center line of County State Aid Highway No. 1; thence Southeasterly along said center line a distance of 305 feet, more or less, to the South line of Section 8, thence Westerly along said South line a distance of 862 feet, more or less, to the point of beginning, according to the United States Government Survey thereof and situate in Washington County, Minnesota, GVWX15 GVWX4 GVWX3 ?@A@95 ?@A@97 ST91 ST52ST50 Map Document: \\arcserver1\GIS\SCANDVAL_TW_MN\ESRI\Pro\Scandia_MN_Aerial\Scandia_MN_Aerial.aprx | Username: jenibr | Date Saved: 1/12/2023 2:29 PMSource: Washington County, MNDot 0 3,700 Feet City Limits Parcels !ILegend Aerial Map City of Scandia, Minnesota January 2023 Subject Property Sunde Engineering, PLLC. 10830 Nesbitt Avenue South • Bloomington, Minnesota 55437-3100 Phone: (952) 881-3344 • Fax: (952) 881-1913 • E-Mail: info@sundecivil.com January 2023 APPLICATION FOR 2023 ANNUAL OPERATORS PERMIT Scandia, MN Consulting Civil Engineers Martin Marietta Page 1 2023 Annual Operators Permit Application January 2023 APPLICATION FOR ANNUAL OPERATORS PERMIT Martin Marietta SAND AND GRAVEL MINING OPERATION CITY OF SCANDIA WASHINGTON COUNTY, MINNESOTA January 2023 I. INTRODUCTION The following Annual Operators Permit (AOP) application is submitted on behalf of Tiller Corporation, a Martin Marietta Materials, Inc. company (herein collectively referred to as “Martin Marietta”) in compliance with the City of Scandia’s Ordinance No. 103 and Chapter 4 of the Development Code: Mining and Related Activities Regulations, Section 6, adopted by the City of Scandia on August 28, 2007. Martin Marietta acquired Tiller in April 2021. Martin Marietta operates a gravel mining and processing operation including an asphalt plant within the City of Scandia. The site has been actively mined since at least 1966. Prior to the incorporation of Scandia in 2006, New Scandia Township and Washington County were the permitting authorities. The City of Scandia adopted two resolutions on May 20, 2008 issuing Conditional Use Permits (CUPs) for the site which is now comprised of the Tiller Mine and Dresel Mine. II. ANNUAL REPORT A. Operating Conditions The site operates in accordance with operating conditions regulated by Section 7 of the Scandia Ordinance 103. 1. Setbacks: No mining, stockpiling or land disturbance activities, with the exception of screening and reclamation activities, are proposed to take place within the setback areas. Minimum setback areas are maintained as follows: a) 50 feet from an adjoining property line b) 200 feet from an occupied structure existing on May 20, 2008. c) 100 feet from any contiguous property subdivided into residential lots of 5 acres or less d) 100 feet from any road right-of-way. 2. Fencing: The majority of the site is fenced with 3 strand wire fencing except where prohibited due to topography, heavy vegetation and wetlands. There are locking metal gates at all entrances to the site. Martin Marietta Page 2 2023 Annual Operators Permit Application January 2023 3. Hours of operation: The site is operated from 7:00 a.m. to 7:00 p.m. Monday through Friday except holidays. Extended hours may be required periodically for situations such as emergencies, accelerated work schedules or weather delays. In accordance with procedures set forth in Ordinance No. 103, extended hours were requested and approved on eight separate occasions in 2022. As part of the request for extended hours, Martin Marietta asked to be notified if the City received any complaints regarding the extended hours of operations. Martin Marietta did not receive any notice of complaints from the City or any members of the public as a result of the extended hours. Summary of the extended hours approved in 2022:  Monday, July 18th from 5 a.m. to 7 a.m. in order to produce the asphalt mix and store it in the insulated silos so that it would be ready-to-go for two large CSAH projects by 7 a.m.  Saturday, August 13th from 7 a.m. to 5:00 p.m. in order to provide asphalt mix to CSAH-26 project located in Center City, Chisago County. The extended hours were needed to keep the project on-schedule due to inclement weather.  Monday, August 15th from 5 a.m. to 7 a.m. in order to produce the asphalt mix and store it in the insulated silos so that it would be ready-to-go for a large order for CR-15 project by 7 a.m.  Saturday, August 20th from 7 a.m. to 5 p.m. to provide asphalt mix to the CR-15 project. The extended hours were needed to keep the project operating within the time constraints established for the road construction project and minimize impacts to the traveling public.  Monday, September 12th from 5 a.m. to 7 a.m. in order to produce the asphalt mix and store it in the insulated silos so that it would be ready-to-go for two CSAH projects by 7 a.m.  Monday, September 19th from 5 a.m. to 7 a.m. in order to produce the asphalt mix and store it in the insulated silos so that it would be ready-to-go for two CSAH projects by 7 a.m.  Saturday, September 24th from 7 a.m. to 5 p.m. in order to provide asphalt mix to CR-3 project. The extended hours were needed to keep the project operating on-schedule due to inclement weather.  Monday, October 10th from 5 a.m. to 7 a.m. in order to produce the asphalt mix and store it in the insulated silos so that it would be ready-to-go for CR- 15 project by 7 a.m. 4. Screening: Screening berms, wooded buffer areas and agricultural fields separate the mining activity from surrounding properties. A large number of trees have been planted in the past to screen site activities. Processing and stockpiling operations are conducted in recessed portions of the site to minimize visibility. 5. Dust control: Major haul roads are hard surfaced and some roads are covered with asphalt millings as dust control measures. A water truck is used to water unpaved portions of the site to control dust. During periods of increased trucking activity, calcium chloride or other approved dust suppressant is applied to provide additional dust control. These practices will continue throughout 2023. Martin Marietta Page 3 2023 Annual Operators Permit Application January 2023 6. Noise: All activities are conducted so as to be in accordance with all Federal, State and City noise standards. 7. Depth of excavation: Depth of excavation will not be lower than 922 feet above mean sea level (msl) for the property described in Resolution No. 05-20-08-02, approving the Conditional Use Permit Application of Dresel Contracting for Sand and Gravel Mining Processing. On the balance of the property, the depth of excavation below the water table will not be lower than 865.87 feet msl. 8. Site clearance: Site clearing activities did not occur in 2022. If clearing activity occurs, it will occur within the 2023 Potential Mining Areas as depicted on Figure 2, Site Plan. 9. Appearance/condition: All buildings, plants and equipment at the site are maintained in a neat condition. Weeds and other unsightly or noxious vegetation are controlled as necessary to preserve the appearance of the reclaimed areas. 10. Sanitary Facilities: The scale and asphalt plant area is served by an individual sewage treatment system. Portable sanitary facilities are provided in the operating areas as required by the Mine Safety and Health Administration. 11. Waste Disposal: Waste generated from the operation is disposed of in accordance with Federal, State and City requirements. 12. Water Quality Monitoring: A plan for groundwater monitoring was developed and approved in conjunction with the CUP permitting process. Groundwater monitoring was conducted in 2022. Water level data is summarized on Table 1 and water quality data is summarized on Table 2, included in the back of this application. 13. Fuel and Chemical Storage: All fuel and chemicals stored on site are stored in accordance with Federal and State standards. On-site fuel storage consists of a 200- gallon above-ground storage tank which is located within a steel secondary containment area and a 1000-gallon above-ground double walled tank located next to the standby electrical generator. When processing and/or reclamation crews are present, an additional 1,000-gallon double walled tank is brought to the site and used to fuel the respective equipment. All asphalt cement storage tanks are above-ground. These tanks consist of two 40,000 gallon tanks and two 32,000 gallon tanks. There is also a 20,000 gallon above-ground used oil storage tank. The used oil is utilized as an alternative fuel supply for the asphalt plant. All tanks containing asphalt cement and used oil are located within a concrete secondary containment area. All tanks are registered with MPCA’s Storage Tank Program. MPCA Site ID 51999 is for the asphalt plant and MPCA Site ID 55016 is for the sand and gravel operation. Small amounts of chemicals utilized by the QM Lab are regulated by Washington County under United States Environmental Protection Agency (EPA) rules. EPA ID Number MND 981 953 417 has been issued for the site which is classified as a Very Small Quantity Generator. Martin Marietta Page 4 2023 Annual Operators Permit Application January 2023 14. Contingency Response Plan: The site operates under a SPCC Plan which is on file with the City of Scandia. 15. Added Provisions: The operator will comply with other such reasonable requirements that the City may find necessary to adopt for the protection of health, safety and welfare and/or prevention of nuisance. 16. Processing: The site operates permanent processing equipment as defined by Ordinance No. 103 in accordance with all Federal, State and City air and water quality and noise standards. Processing equipment is screened from view from other properties and adjacent roads. Portable crushing equipment is placed on the floor of the facility and setbacks per Ordinance No. 103 are maintained between the processing equipment and the property lines. 17. Recycling: Recycling activity at the facility meets all applicable standards contained in Section 7.1 (1) of Ordinance No, 103. A Solid Waste Storage Facility license that authorizes the storage of unprocessed concrete, concrete products and brick and a Recycling Facility license that authorizes the storage and processing of recycled asphalt products are reissued annually to Martin Marietta by Washington County. General and Specific Conditions are established for each license and are reviewed on an annual basis and may include an annual inspection completed by the County. A copy of the Annual Report to Washington County is available upon request. 18. Trucking Operations: The site has access to County Road 15 (Manning Trail N.), County Road 91 (Lofton Avenue N.) and 218th Street North. These are hard-surfaced roads. 19. Asphalt Plants: The site operates a permanent asphalt plant and the plant was in operation at the time the City adopted its mining ordinance. Therefore, the plant may expand in the future subject to the setbacks set forth in Section 7.1(1) of Ordinance No. 103. The plant operates in accordance with all Federal, State, and City air, water and noise quality standards. B. Compliance with Conditions of the CUP 1. Updated Copy of Application Material: A completed bound book that includes all of the information and plans submitted to the City during the CUP process was previously submitted and is on file at the City. 2. Watershed District Permit: The Watershed District Permit, P08-003, was revised in 2019 to align the permit with the City’s annual review process and eliminate a 5- year term on the permit. The revisions to the permit were approved by District Managers during their February 13, 2019 Regular Meeting. 3. Monitoring Wells: All required monitoring wells have been installed. Martin Marietta Page 5 2023 Annual Operators Permit Application January 2023 4. Groundwater Monitoring Plan: A monitoring plan with protocols is on file with the City. In May 2022, Martin Marietta received authorization from MN DNR to increase its annual water appropriation from 20 MGY to 30 MGY for aggregate production and dust control. With the increased water appropriation, a short-term monitoring plan was developed and implemented to help evaluate aquifer recovery to pre-pumping water levels following pumping during periods of high use. Data collected in accordance with the short-term monitoring plan was submitted to the City in August 2022. 5. Excavation Below Water Table: In 2022, excavation into the groundwater table did not occur. In 2023, excavation into the groundwater table is expected to occur within the 2023 Potential Mining Area as depicted on Figure 2, Site Plan. Water level data is collected on an on-going basis and submitted annually to the City (see Table 1). 6. Production Well Records: Records of the production well are kept. They are summarized on Table 3. 7. Groundwater Analysis: Groundwater samples are collected and analyzed for DRO in accordance with the groundwater monitoring plan. Table 2 summarizes the results. DRO was not detected in any of the monitoring wells. Results have been supplied to the City. Currently, no gasoline is stored on site. If gasoline is stored on- site in the future, GRO will be added to the analyte list. 8. MN County Well Index: A figure which illustrates the site and MN County Index wells is on file at the City. 9. Setback from Proposed Lake: The asphalt plant and related structures will be setback at least 100 feet from the edge of the water body that will be created as part of mining operations. 10. Lake Depth: The maximum excavation into the water table will be no more than 50 feet. The maximum excavation elevation of 865 feet amsl has been established in previous AOP’s. 11. Truck Hauling Signs: Washington County has posted Lofton and Manning Avenues per the County’s requirements. Martin Marietta has posted signs on 218th Street per the City of Scandia requirements. 12. Lofton/Hwy 97 Intersection: Martin Marietta restricts importing add-rock from Lofton Ave. N. during non-daylight hours as defined in their CUP. 13. 228th Street Sign: Martin Marietta has posted a sign at the Lofton Ave. N. exit that restricts trucks from using 228th Street. Martin Marietta Page 6 2023 Annual Operators Permit Application January 2023 14. Reclamation and Sequencing Plan: A Reclamation Plan and Phasing Plan is on-file with the City. Current reclamation progress is indicated on Figure 2, Site Plan, submitted with this AOP application. C. Annual Activity 1. Amount of material removed from the site: Approximately 378,000 tons of material was removed in 2022. 2. Amount of add-rock brought onto the site: Approximately 92,000 tons of Class A, Class B, Class C and Class D add-rock were imported to the site in 2022. 3. Area reclaimed and type of reclamation: Reclamation activities in 2022 included placement of overburden and suitable fill material along the slopes of the mining area, north of the Tiller Mine/Dresel Mine common mining border . The completed and ongoing reclamation areas are indicated on Figure 2, Site Plan. Ongoing reclamation activities are anticipated north and south of the Tiller Mine/Dresel Mine common mining border and primarily along the east half of the mining area during 2023. These areas are shown on Figure 2, Site Plan as 2023 Potential Reclamation Activity. Some of the areas shown as potential reclamation will also see active mining during 2023. Once mining is complete, reclamation may advance into these areas during 2023. 4. Average number of trips hauling material to and from the site per day for the season: The average number of trucks travelling to and from the site per day in 2022 was approximately 214 trucks per day. 5. On July 19, 2022 the Scandia City Council adopted Resolution No. 2022-27 amending the Future Land Use Map to remove the Mining Overlay designation from PID 17.032.20.21.0005. This parcel, which is approximately 10-acres, was previously mined and reclaimed as part of the original Dresel Mine. The lot previously shared a common mining and reclamation border with the Dresel Mine. Martin Marietta intends to reserve the ability to perform reclamation and future screening berm removal work within the setback area that might be needed to accommodate future development on their property, as needed. D. Description of operating conditions planned for the coming year: During the 2023 mining season, the site will continue to operate as it has in the past. The mining operation includes the removal of overburden, excavation of sand and gravel, crushing, washing, screening, stockpiling, and recycling of concrete and asphalt products. Portable crushing, washing and screening plants are brought to the site periodically and material is excavated, processed, and stockpiled. Asphalt is produced and sold throughout the construction season and add rock materials are delivered to the site as needed. The 2023 production schedule anticipates mining and processing in 2023. The exact area of excavation will depend on the required gradation of the end products. Mining anticipated Martin Marietta Page 7 2023 Annual Operators Permit Application January 2023 during 2023 will occur within the 2023 Potential Mining Area and some of the Potential Reclamation Areas as indicated on Figure 2, Site Plan. Aerial Photo: Figure 1, Aerial Photo, is attached which includes a July 7, 2022 aerial photo and identifies the Mining Limit, the Tiller Mine property boundary and the Dresel Mine property boundary. Site Plan: Figure 2, Site Plan, is attached which illustrates the 2023 potential active mining area, reclamation area, stockpile and processing area, reclaimed area and the current limits of excavation into groundwater. Reclamation: Ongoing reclamation activities are anticipated north and south of the Scandia Mine/Dresel Mine common mining border and primarily along the east half of the mining area during 2023. These areas are shown on Figure 2, Site Plan as 2023 Potential Reclamation Activity. Operating Conditions for 2023: The 2023 production schedule anticipates mining and processing during 2023. Mining will occur within the 2023 Potential Mining Area as indicated on Figure 2, Site Plan. The exact area of excavation will depend on the required gradation of the end products. E. Inspection: The City conducts an annual inspection of the site. The last inspection occurred on December 8, 2022. III. CERTIFICATION I certify that the plans, specifications or reports for the above described facility were prepared by me or under my direct supervision and that I am a duly Registered Professional Engineer under the laws of the State of Minnesota. Kirsten Pauly Date: January 31, 2023 Reg. No. 21842         Tables Table 1: Scandia Groundwater Elevation Data Groundwater elevation levels are recorded in feet above mean sea level NM=Not Measured (due to obstruction) MW-2 Taken out of service 6/21/2011 PZ-4 Taken out of service 5/12/2020 914.99 = Apparent incorrect reading at time of field visit Date Scandia Production Well Scandia PZ-3 Scandia PZ-4 Scandia PZ-5 Scandia PZ-6 Scandia MW-1 Scandia MW-2 Scandia On- Site Pond 10/21/2022 916.45 916.57 917.94 915.16 917.21 919.23 9/14/2022 916.57 916.77 918.27 915.32 917.36 8/23/2022 916.60 916.90 918.49 915.42 918.25 919.41 7/18/2022 916.59 916.82 918.23 915.28 919.72 919.39 6/1/2022 917.11 917.17 918.35 915.81 920.00 919.62 5/13/2022 917.30 917.34 918.30 915.95 921.16 920.12 10/20/2021 917.89 917.95 919.48 916.57 920.81 919.30 9/8/2021 918.16 918.26 919.82 916.85 921.10 8/30/2021 918.27 918.31 919.79 916.93 921.16 920.78 7/27/2021 918.24 918.35 919.94 916.96 921.25 919.68 6/24/2021 NM 919.09 920.29 917.21 921.67 920.30 5/21/2021 NM 918.47 920.27 917.11 921.73 920.38 4/15/2021 918.88 918.95 920.47 917.61 921.86 920.34 10/23/2020 919.41 919.53 921.31 918.12 922.21 921.80 9/17/2020 919.63 919.75 921.58 918.29 922.64 922.12 8/27/2020 919.74 919.80 921.52 918.41 922.64 922.21 7/31/2020 919.26 918.85 920.74 917.91 922.08 6/22/2020 919.29 919.12 920.91 917.75 922.15 921.69 5/22/2020 919.08 919.17 920.02 916.01 921.47 4/23/2020 918.26 918.31 919.85 919.28 916.30 921.35 3/31/2020 918.94 918.97 920.39 920.38 917.64 921.74 10/31/2019 918.41 918.47 919.82 919.94 917.11 921.19 9/9/2019 918.10 918.13 919.75 919.63 916.79 920.99 8/30/2019 917.86 917.89 919.68 919.64 916.55 920.89 7/11/2019 917.73 917.48 919.15 919.20 916.20 920.26 5/10/2019 917.35 917.42 918.95 918.46 916.02 920.33 919.70 4/30/2019 917.23 917.31 919.04 918.4 915.93 922.47 10/24/2018 916.84 916.99 918.57 918.7 916.18 919.88 9/24/2018 917.12 917.17 918.82 918.44 915.83 920.08 8/30/2018 NM 916.95 918.52 918.41 915.62 919.89 7/26/2018 917.06 917.02 918.67 918.44 915.63 920.04 6/6/2018 NM 916.83 918.60 918.36 915.56 919.97 918.11 5/1/2018 917.13 917.2 918.36 918.46 915.88 920.08 918.23 4/25/2018 917.12 917.16 918.7 918.52 915.88 920.13 11/30/2017 917.53 917.61 919.06 919.12 916.29 921.44 919.17 10/31/2017 NM 917.52 919.26 919.21 916.20 920.57 918.91 9/28/2017 917.63 917.71 NM 919.23 916.44 920.53 8/24/2017 917.69 917.75 919.18 NM 916.41 920.53 7/20/2017 917.35 917.48 919.06 919.04 916.32 920.4 6/15/2017 917.35 917.48 918.76 918.67 916.11 920.2 5/16/2017 917.00 917.05 918.5 918.31 915.73 919.83 4/27/2017 916.89 916.95 918.34 NM 915.67 919.71 10/3/2016 916.35 916.39 917.86 917.56 915.13 919.17 917.24 9/27/2016 916.33 916.30 917.86 917.40 914.94 919.18 8/16/2016 915.97 916.00 917.50 917.28 914.75 918.79 7/6/2016 915.68 915.71 917.12 916.57 914.44 917.35 5/20/2016 914.40 914.09 915.63 915.17 913.00 916.66 10/5/2015 914.35 914.38 915.90 915.51 913.15 917.19 915.43 9/29/2015 914.34 914.33 915.88 915.38 913.05 917.18 8/11/2015 914.05 914.08 915.60 915.14 912.80 916.88 7/16/2015 913.77 913.80 915.38 914.90 912.57 916.69 6/18/2015 913.52 913.52 915.00 914.74 912.31 916.36 Page 1 of 3 Date Scandia Production Well Scandia PZ-3 Scandia PZ-4 Scandia PZ-5 Scandia PZ-6 Scandia MW-1 Scandia MW-2 Scandia On- Site Pond 5/18/2015 913.37 913.40 914.87 914.63 912.16 916.18 4/17/2015 913.39 913.42 914.88 914.75 912.23 916.23 10/9/2014 913.83 913.96 915.44 915.17 912.71 916.77 914.7 9/17/2014 914.00 914.06 915.49 915.12 912.81 916.79 8/19/2014 913.85 913.91 915.36 914.96 912.64 916.66 7/9/2014 913.64 913.69 915.18 914.58 912.41 916.48 6/18/2014 913.41 914.99 914.92 915.72 913.68 916.20 5/12/2014 913.03 913.08 914.56 913.93 912.84 915.85 4/22/2014 912.58 912.60 914.07 913.74 911.38 915.43 11/20/2013 912.88 912.89 914.35 914.20 911.70 915.74 10/25/2013 912.98 913.03 914.50 914.30 911.80 915.83 913.91 9/26/2013 913.00 913.05 914.52 914.29 911.81 915.88 8/27/2013 913.17 913.23 914.66 914.43 911.98 916.03 7/25/2013 913.19 913.29 914.75 914.41 912.06 916.09 6/25/2013 913.17 913.17 914.66 914.18 911.95 915.98 5/23/2013 912.92 912.94 914.45 913.92 911.62 915.79 913.99 4/25/2013 912.90 912.90 914.43 913.88 911.60 915.78 12/5/2012 912.93 912.99 914.45 914.28 911.70 915.83 10/25/2012 913.14 913.19 914.64 914.50 911.98 916.01 914.17 9/26/2012 913.25 913.29 914.78 914.57 912.03 916.16 9/5/2012 913.44 913.48 914.94 914.83 912.28 916.31 7/26/2012 913.71 913.74 915.22 914.89 912.50 916.52 6/26/2012 913.67 913.67 915.12 914.89 912.50 916.46 5/22/2012 913.37 913.38 914.92 914.61 912.22 916.25 4/23/2012 913.22 913.22 914.69 914.50 912.07 916.07 914.13 3/29/2012 913.26 913.27 914.78 914.53 912.09 916.14 11/10/2011 913.74 913.78 915.19 914.99 912.55 916.55 10/3/2011 913.78 913.83 915.27 915.00 912.60 916.62 914.74 9/8/2011 913.78 913.81 915.29 914.90 912.59 916.61 8/5/2011 913.71 913.72 915.24 914.56 912.44 916.55 7/13/2011 913.30 913.36 914.83 914.34 912.07 916.17 6/21/2011 913.13 913.19 914.65 914.14 911.97 915.99 916.13 6/6/2011 913.06 913.10 914.52 913.97 911.89 915.88 916.02 914.18 5/6/2011 912.70 912.74 914.16 913.69 911.53 915.53 915.68 4/7/2011 912.46 912.48 913.97 913.49 911.22 915.35 915.50 11/23/2010 912.29 912.32 913.84 913.47 911.02 915.18 915.32 10/19/2010 912.46 912.45 913.98 913.62 911.24 915.34 915.46 9/14/2010 912.37 912.38 913.91 913.55 911.11 915.23 915.36 8/9/2010 912.37 912.38 913.92 913.56 911.12 915.22 915.35 7/6/2010 912.47 912.46 NM 913.57 911.19 915.28 915.40 6/7/2010 912.39 912.41 913.94 913.65 911.17 915.30 915.43 4/27/2010 912.51 912.53 914.03 913.77 911.28 915.42 915.54 11/5/2009 913.14 913.15 914.70 914.37 911.89 916.07 916.14 10/21/2009 913.17 913.17 914.72 914.50 911.93 916.08 916.17 914.30 9/10/2009 913.28 913.30 914.85 914.55 912.04 916.22 916.31 8/6/2009 913.28 913.39 914.88 914.70 912.15 916.27 916.35 6/11/2009 913.55 913.58 915.08 914.83 912.36 916.49 916.60 5/18/2009 913.67 913.70 915.19 914.94 912.51 916.61 916.69 4/6/2009 913.79 913.81 915.35 915.04 912.60 916.78 916.86 10/30/2008 914.35 914.37 915.87 915.60 913.13 917.31 917.37 9/16/2008 914.51 914.57 916.06 915.81 913.28 917.48 917.54 8/7/2008 914.60 914.65 916.20 915.80 917.60 917.65 7/9/2008 914.54 914.58 916.13 915.68 917.55 917.61 6/9/2008 914.44 914.50 915.99 915.53 917.44 917.51 5/14/2008 914.29 914.34 915.38 917.29 917.37 5/6/2008 914.26 914.31 3/28/2008 914.07 914.11 2/22/2008 914.16 914.18 1/9/2008 914.30 NM 12/12/2007 914.48 NM 11/8/2007 914.70 914.74 Page 2 of 3 Date Scandia Production Well Scandia PZ-3 Scandia PZ-4 Scandia PZ-5 Scandia PZ-6 Scandia MW-1 Scandia MW-2 Scandia On- Site Pond 10/11/2007 914.64 914.68 9/11/2007 914.60 914.64 7/19/2007 914.77 914.82 6/13/2007 914.85 914.91 5/2/2007 915.06 915.11 9/6/2006 915.87 915.90 Page 3 of 3 Table 2 Water Quality Results Potable Well: Date Diesel Range Organics mg/L Total Suspended Solids mg/L Nitrogen, Ammonia mg/L Phosphorous mg/L 9/14/2022 ND 9/8/2021 ND 9/17/2020 ND 9/9/2019 ND 9/26/2018 ND 9/28/2017 ND 9/27/2016 ND 9/29/2015 ND 9/25/2014 ND 9/26/2013 ND 9/26/2012 ND 9/29/2011 ND 9/14/2010 ND 10/21/2009 ND ND 0.051 ND Production Well: Date Diesel Range Organics mg/L Total Suspended Solids mg/L Nitrogen, Ammonia mg/L Phosphorous mg/L 9/14/2022 ND 9/8/2021 ND 9/17/2020 ND 9/9/2019 ND 9/26/2018 ND 9/28/2017 ND 9/27/2016 ND 9/29/2015 ND 9/25/2014 ND 9/26/2013 ND 9/26/2012 ND 9/29/2011 ND 9/14/2010 ND 10/21/2009 ND ND 0.053 ND Page 1 of 4 PZ-3: Date Diesel Range Organics mg/L Total Suspended Solids mg/L Nitrogen, Ammonia mg/L Phosphorous mg/L 9/14/2022 ND 9/8/2021 ND 9/17/2020 ND 9/9/2019 ND 9/26/2018 ND 9/28/2017 ND 9/27/2016 ND 9/29/2015 ND 9/25/2014 ND 9/26/2013 ND 9/26/2012 ND 9/29/2011 ND 9/14/2010 ND 10/21/2009 ND ND 0.18 0.65 PZ-4: Taken out of service May 12, 2020 Date Diesel Range Organics mg/L Total Suspended Solids mg/L Nitrogen, Ammonia mg/L Phosphorous mg/L 9/9/2019 ND ND ND ND 9/26/2018 ND ND ND ND 10/20/2017 ND ND ND ND 9/27/2016 ND ND ND 0.074 9/29/2015 ND 16.0 ND 0.052 9/25/2014 ND 23.0 0.092 0.081 9/26/2013 ND 46.4 0.13 0.11 9/26/2012 ND 942 0.14 0.39 9/29/2011 ND 65.3 0.041 0.094 9/14/2010 ND 161 0.15 0.15 10/21/2009 ND 102 0.048 ND Page 2 of 4 PZ-6 Date Diesel Range Organics mg/L Total Suspended Solids mg/L Nitrogen, Ammonia mg/L Phosphorous mg/L 9/14/2022 ND 124 ND 0.10 9/8/2021 ND ND ND ND 9/17/2020 ND ND ND ND 9/9/2019 ND ND ND 0.10 9/26/2018 ND ND ND 0.18 9/28/2017 ND ND ND 0.072 9/27/2016 ND 134 ND 0.20 9/29/2015 ND ND ND 0.061 9/25/2014 ND ND 0.058 0.084 9/26/2013 ND ND 0.079 0.071 9/26/2012 ND ND 0.077 ND 9/29/2011 ND ND 0.071 ND 9/14/2010 ND 11.7 0.098 0.084 10/21/2009 ND 11.3 0.1 ND Pond Date Diesel Range Organics mg/L Total Suspended Solids mg/L Nitrogen, Ammonia mg/L Phosphorous mg/L 9/14/2022 ND ND ND ND 9/8/2021 ND ND ND ND 9/17/2020 ND ND ND ND 9/9/2019 ND ND ND ND 9/26/2018 ND ND ND ND 9/28/2017 ND ND ND ND 9/27/2016 ND 11.0 ND 0.061 9/29/2015 ND ND ND 0.96 9/25/2014 ND ND 0.096 ND 9/26/2013 ND ND 0.089 ND 9/26/2012 ND ND 0.078 ND 9/29/2011 ND ND 0.069 ND 11/5/2010 ND NA NA NA 9/14/2010 .11*ND 0.057 ND 10/21/2009 ND ND ND ND Page 3 of 4 *Upon Detection of Diesel Range Organics (DRO) above the reporting limit of 0.10 mg/l, the sample was further analysed for the presence of Polycyclic Aromatic Hydrocarbons (PAHs) which were not detected. As additional follow up, the pond was resampled for DRO in November, 2010 at the request of the City. Although not required, initial baseline data were obtained for all wells and results reported herein. Background data has been collected voluntarily for PZ-5, MW-1 and MW-2 in the past and is available upon request. Page 4 of 4 Table 3 Production Well Records Scandia Mine Pumping Records: 2022 Production Well Month Amount Pumped (Gal) January 0 February 0 March 0 April 0 May 53,750 June 2,910,575 July 2,096,700 August 474,125 September 165,000 October 90,000 November 20,000 December 0 5,810,150 Total Pumped in 2022: Water Appropriation Permit authorizes withdrawal of up to 30 million gallons per year. Figures TILLER MINE MINING LIMITS MINING LIMITS MINING LIMITS DRESEL MINE COMMON MINING BORDER Engineering, PLLC. Sunde Figure 1 Aerial Photo Annual Operators Permit Aerial image from Kespry Aerial Photo (collected via UAV on July 7, 2022) over active portions of Mine and 2021 FSA Aerial Photo from Minnesota Geospatial Image Service over remaining areas. PEMBgPEMBPEMBPEMBPEMCPSS1BPEMBPUBGPEMBPEMCPEMBPEMBPEMBPSS1BPEMCPEMCxPEMBPEMCPEMCPUBGPUBGPFO1CPEMCPSS1/3BPEM/SS1BPEMCPEMAPEMCPEMCPEMCPEMBPEMB SS1PSS1BPEMCPEMCPSS1BPEMCPEMCPUBG218TH ST. N.PSSIBPEMFPEMCPEMCMW-1PZ-5PZ-6PZ-3PRODUCTIONWELLSCALE HOUSEWELLSTOCKPILE ANDPROCESSINGAREA(Future Mining)RECLAIMEDAREARECLAIMEDAREARECLAIMEDAREAMININGLIMITSSCREENING BERMLOCKINGGATEMININGLIMITSMININGLIMITSRECLAIMEDAREAHAUL RD. TOLOFTON AVE.DRESEL MINETILLER MINE2023 POTENTIALMINING AREA2023 POTENTIALMINING AREAHAULROADLOCKINGGATELOCKINGGATE SCREENING BERMMaintain 50'Wetland Setback2023 POTENTIALRECLAMATIONAREAMaintain 50'Wetland SetbackCURRENT LIMITSOF EXCAVATIONINTOGROUNDWATER2023 POTENTIAL RECLAMATION AREA -INCLUDES RECLAMATION OF A PORTIONOF THE GROUNDWATER PONDSTAFF GAUGEINSTALLED ATNORTH END OFGROUNDWATERPONDCOMMON MINING BORDERSHEET NO:DATE:DRAWN BY:CHECKED BY:SCALE:APPROVED BY:PROJECT NO.:REG. NO.:DATE:I HEREBY CERTIFY THAT THIS PLAN,SPECIFICATION, OR REPORT WAS PREPAREDBY ME OR UNDER MY DIRECT SUPERVISIONAND THAT I AM A DULY LICENSEDPROFESSIONAL ENGINEER UNDER THE LAWSOF THE STATE OF MINNESOTA.DESCRIPTION:INFORMATION:REVISIONDATEEngineering, PLLC.CONSULTING CIVIL ENGINEERS10830 NESBITT AVENUE SOUTHBLOOMINGTON, MINNESOTA 55437(952) 881-3344 TELEPHONE(952) 881-1913 FAXwww.sundecivil.comSundeKirsten Pauly 93-253KPGraphic12/28/16KP1 of 1Figure 2218421/19/2023SITE PLANTILLERCORPORATIONSCANDIA,MINNESOTAANNUALOPERATORS PERMITNOTES:1.TOPOGRAPHY WITHIN MINE LIMITS FROM 9/13/2021 UMV FLIGHT.REMAINING TOPOGRAPHIC INFORMATION FROM 2011 LiDARELEVATION, TWIN CITIES METRO REGION, MINNESOTA 2.SETBACKS. THE FOLLOWING MINING SETBACKS WILL BE MAINTAINED:·50' FROM PROPERTY LINE·200' FROM OCCUPIED STRUCTURES·100' FROM ANY CONTIGUOUS PROPERTY SUBDIVIDEDINTO RESIDENTIAL LOTS OF FIVE (5) ACRES OR LESS(NOT APPLICABLE)·100' FROM ROAD R-O-WPROCESSING AREA SHOWN REFLECTS CURRENTCONDITION. PROCESSING AREAS WILL CHANGEWITH THE PROGRESSION OF MINING. MULTIPLEPROCESSING OPERATIONS MAY BE LOCATEDTHROUGHOUT THE PROCESSING AREA ORAREAS. CERTAIN PROCESSING OPERATIONSREQUIRE EQUIPMENT TO BE PLACED NEAR THEVARIOUS MATERIALS NEEDED TO MAKE SPECIFICPRODUCTS AND OTHER PROCESSINGOPERATIONS NEED TO BE PLACED IN A MANNERTHAT AVOIDS CONFLICTS WITH THE ACTUALMINING.ADDITIONAL MINING MAY BE REQUIRED IN POTENTIALRECLAMATION AREAS. Mining Limit95098097094095096097098099093095 0 9 6 0 9 7 0970 9809909 8 0 9 9 0 1000 10109309409609801000950960970980940950960930940950960970980950950 960960 940950960950950960960950 960 970950960 9609 6 0 970 970980990940950 960 970 930 940 950 960 93 0 940950 9 6 0960960950950960960 96 0 960960960970970970980 980 9609709309509 9 094097098098099099099010001000100010101010 940 950960970980990 930940960940950930940 95096097098099010001010 950960970980980980980980990 9909909901000 100010001000 1010 10101010 9509609609609709709 8 0 980970970 97098098 0 980980 970980960 960970980 990940 950 96 0 960970970920930940950960970 970 970980980980980980980 980990990 990990990990990990 990 1000 10001000960970980980 99 0 990990990990 1000100 0960960970970 980 99010001010960 960970980 970 1000 95097 0 9 4 0 950 960930980990970 950950960 960940 95096093 0 W.E.933.322044Z 995.73022045Z 989.82011043E 692146.185N 120313.24022046Z 950.800MANNING AVENUE EAST 1223.25S 89°22'12" W 1422.96S 89°41'05" W 1287.61S 89°19'52" W 1277.99N 89°57'12" E 2649.44S 89°44'30" E 693.00N 89°52'27" E 983.08N 5°42'43" E 62 3 . 5 1 N 89°37'35" E631.03R = 2291.82 = 0°26'05" L = 17.39 R = 1909.86 = 9°57'32" L = 331.96 N 12°23' 4 6 " E 9 0 6 . 9 4 N 1°25'56" E 1420.46 N 0°35'31" W 1317.76 S 1°01'20" E 1325.79 S 41°53'22" W363.70 S 17°44'22" W428.16L = 331.96 = 9°57'32"R = 1909.86L = 331.96 = 9°57'32"R = 1909.86L = 331.96 = 9°57'32"R = 1909.86249.34 S 0°01'45" W 659.62 S 0°33'43" E 1319.60 1978.57 50' SETBACK4:1 SLOPESS 89°31'35"W65.46NSP CO. EASEMENTR = 1980.97 = 20°29'54" L = 674.38 963.2955.5958.5956.9964.4962.4969.7962.4958.2962.9961.3970950970960940972.8960.2973.8968.9966.3959.2951.3945.2942.6945.6962.4945.2940.8940.2944.2950.7954.4957.6958.3957.6953.7948.8962.3956.1961.9972.7994.9969.4969.6965.5981.3974.5930.4939.9956.8968.6974.4959.0928.2958.2962.9986.750' SETBACKGATELOFTON ROAD970980960950940920930950960990 980 970 960 950 940 930 920 940930920950960970980990960960950920 940930 916±100 FEETVARIESMINIMUM TOPSOIL ANDSEEDED TO ESTABLISHNATIVE VEGETATION6:1 SLOPE FOR AHORIZONTALDISTANCE OF 100'SLOPE VARIES- 4:1 MAX.146:1 SLOPE61VARIESSLOPE VARIES- 3:1 MAX.13TYPICAL SECTION EDGE OF WATER BODYDEPTHVARIES218TH ST. N.LOFTON AVE. N.10001000990980970970980990970980960950940920930950960990 980 970 960 950 940 930 920 940930920950960970980990960960950920 9409301000 9309409509609709809901000932934936938922924926928930940950960PROPOSED FUTURE LAKE CONFIGURATIONWATER ELEVATION AT 916+/-BOTTTOM OF LAKE AT 870-8904.ISHEET NO:DATE:DRAWN BY:CHECKED BY:SCALE:APPROVED BY:PROJECT NO.:REG. NO.:DATE:I HEREBY CERTIFY THAT THIS PLAN,SPECIFICATION, OR REPORT WAS PREPAREDBY ME OR UNDER MY DIRECT SUPERVISIONAND THAT I AM A DULY LICENSEDPROFESSIONAL ENGINEER UNDER THE LAWSOF THE STATE OF MINNESOTA.DESCRIPTION:INFORMATION:REVISIONDATET. , R. , S. #DRAWING: \\Kirstensoldpc\dwgs\a-Tiller - All\Tiller Scandia\Annual Operators Permit\AOP 2023\Figure 3 - 2023 AOP Mining and Reclamation Plan.dwg LAYOUT: C3 11x17Engineering, PLLC.CONSULTING CIVIL ENGINEERS10830 NESBITT AVENUE SOUTHBLOOMINGTON, MINNESOTA 55437(952) 881-3344 TELEPHONE(952) 881-1913 FAXwww.sundecivil.comSundeKIRSTEN PAULY 93-253 KPGraphic10/18/07 1 of 7Figure 3218421/19/2023 GL7,8 2032 93-253MINING ANDRECLAMATIONPLAN600300300TILLERCORPORATIONSCANDIA,MINNESOTAANNUALOPERATORS PERMIT From: Dave Hume <dave.hume@lrewater.com> Sent: Friday, March 10, 2023 5:18 PM To: TJ Hofer Cc: Anne Hurlburt; Christina Morrison Subject: Tiller 2023 AOP Application Review - LRE Water Attachments: Groundwater Elevations - All Wells (10-21-22).pdf Follow Up Flag: Follow up Flag Status: Flagged Hi, TJ. LRE Water (LRE) has reviewed the groundwater monitoring data in Tiller’s (Martin Marietta) 2023 AOP Application for the Tiller/Dresel Mine on Manning Ave. The well and pond hydrographs (attached) have been updated to include the 2022 water level data. Annual precipitation data from the National Weather Service for the Minneapolis- St. Paul area are also included on the graph. 2022 Groundwater Monitoring Data Review The 2022 groundwater monitoring was completed in accordance with the approved monitoring plan. Groundwater samples were collected from the monitoring well and piezometers, pond, production well and potable well on 9/14/22. These were analyzed for Diesel Range Organics (DRO) as outlined in the monitoring plan. DRO was not detected above the method detection limit in any of the samples. These results and the other groundwater chemistry results indicate no groundwater quality concerns. The groundwater flow direction across the site is generally to the north and is consistent with previous submittals. From October 2021 through October 2022, groundwater levels across the site declined from approximately 1.4 feet in piezometer PZ-6 to approximately 3.6 feet in monitoring well MW-1. The most recent levels measured on October 2022 are still approximately 4 to 5 feet higher than the lowest levels measured in 2010. The decrease in water levels observed in since the fall of 2020 is the result of local and regional changes in precipitation, and unrelated to mining operations and pumping by the production well. This is shown by the annual precipitation data that is plotted with water levels on the attached hydrograph (Figure 1). The water levels and precipitation show similar trends over time. Summary of the 2022 Aquifer Pumping Test Results The 2022 AOP required a short-term monitoring plan be developed and implemented this year to evaluate potential for regional impacts from groundwater pumping associated with aggregate washing at the Site. The plan was in response to the MN DNR’s approval of the increase in groundwater appropriations from the Site production well from 20 million gallons per year (MGY) to 30 MGY on May 26, 2022. The plan was implemented by Martin Marietta with assistance from their consultant, Sunde Engineering. The plan included the following activities: A pumping test that was completed during a period of highest production well use. The production well was pumped at approximately 475 to 500 gallons per minute (gpm) beginning on 6/13/22. Water levels were monitored in the production well, PZ-3 and the staff gage in the pond using pressure transducers and data loggers, and measured manually periodically. Monitoring continued through 7/1/22. (Note that the Production Well had to be shut off periodically when the sedimentation basins were full; however, this did not interfere with the test and results.) . Summary of results: The results from the plan provided the information necessary to evaluate the aquifer’s response to pumping at the site at the highest pumping demand, and assess any regional impacts. Water levels in the production well declined approximately 5 to 7 feet when pumping for approximately 12 hours at rates of approximately 475 to 500 gpm. When the pump shut off, water levels recovered to their pre-pumping levels quickly, and before the next pumping cycle began. Groundwater levels at PZ-3 (located approximately 300 feet from the production well) appeared to have less than 0.5 feet of decline, if any, during the pumping phases. Water levels in the pond were not influenced by pumping. The observed groundwater level declines and rate of groundwater level recovery indicate a very prolific aquifer. Based on the information to date, there no concerns to the resource when pumping at the rates necessary to meet the facility’s peak demands under normal operations. The data files and data plots from the test are not included in this email; however, they are on file with the City or can be obtained from LRE Water or Martin Marietta. 2022 Recommendations Continue the annual sampling for water quality parameters as outlined in the monitoring plan. Continue to map the area(s) of excavation into the water table. Please let me know if you have any questions, or need additional information. Thank you, Dave Hume, PG Sr. Project Manager & VP Midwest Operations Cell: 612-805-0919 Dave.Hume@LREwater.com LREWATER.COM **CONFIDENTIALITY NOTICE: This email message is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message. Thank you. U:\5028SCA01_Scandia Tiller Manning\Hydrogeo\Groundwater Elevations - All Wells (10-21-22).xlsxGW Elev All Wells1015202530354045910912914916918920922924Annual Precipitation (inches)Elevation (ft amsl)DateFIGURE 1GROUNDWATER AND POND ELEVATIONS WITH ANNUAL PRECIPITATION VS. TIME5/2008 - 10/21/2022TILLER (MARTIN MARIETTA) MINESCANDIA, MINNESOTAPZ-4PZ-5MW-1MW-2 (aband. June 2011)PZ-6Prod WellPZ-3PondAnnual PrecipitationNote: Annual precipiation from National Weather Service Mnneapolis‐St. Paul Areahttps://www.dnr.state.mn.us/climate/historical/acis_stn_data_monthly_table.html?sid=mspthr&sname