Magellan Rochester Terminal Expansion Project Findings of ... · p-ear2-155b. Printed on recycled paper containing at least 30% fibers from paper recycled by consumers. STATE OF MINNESOTA

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Printed on recycled paper containing at least 30% fibers from paper recycled by consumers

STATE OF MINNESOTA MINNESOTA POLLUTION CONTROL AGENCY

IN THE MATTER OF THE DECISION ON THE NEED FOR AN ENVIRONMENTAL IMPACT STATEMENT FOR THE PROPOSED MAGELLAN ROCHESTER TERMINAL EXPANSION PROJECT EYOTA TOWNSHIP OLMSTED COUNTY, MINNESOTA

FINDINGS OF FACT CONCLUSIONS OF LAW AND ORDER

Pursuant to Minn. ch. 4410, the Minnesota Pollution Control Agency (MPCA) staff prepared and distributed an Environmental Assessment Worksheet (EAW) for the proposed Magellan Pipeline Company, L.P. Project. Based on the MPCA staff environmental review, the EAW, comments and information received during the comment period, and other information in the record of the MPCA, the MPCA hereby makes the following Findings of Fact, Conclusions of Law, and Order.

FINDINGS OF FACT

Project Description 1. Magellan Pipeline Company, L.P. (Magellan) proposes to expand its existing refined products

terminal at 1331 Highway 42 Southeast, Eyota Township, Olmsted County (Facility). The Facility has been in operation since 1966.

2. The existing Facility consists of the following components:

· Twenty regulated aboveground storage tanks (ASTs) which store refined petroleum products, ethanol, biodiesel and fuel additives. The ASTs have an accompanying secondary containment structure

· Two loading bays for offloading gasoline and diesel fuel to tanker trucks · Piping to transfer fuel products from the ASTs to the offloading bays · One biodiesel offloading area · One butane offloading area · One vapor combustion unit (VCU) to control air emissions when loading gasoline into tanker

trucks · One stormwater collection and infiltration basin · One potable water supply well (Unique Well ID 227374) · Two monitoring wells (Unique Well IDs 558143 and 558144) · One office building · One onsite septic system

3. Magellan proposes the following changes to the existing Facility (Project):

· Addition of a single 5 million gallon gasoline AST with secondary containment structure · One new water well · One new gasoline/diesel fuel loading bay

On the Need for an Environmental Impact Statement Findings of Fact Magellan Rochester Terminal Expansion Project Conclusions of Law Eyota Township, Olmsted County And Order

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· Additional pumps, above-ground piping, and a motor control center building · Relocation of the existing biodiesel offloading area · One vapor recovery unit (VRU) to capture gasoline vapors · Modifying existing traffic routes within the Facility · Modifying the existing Facility electrical infrastructure · Installation of underground piping to route stormwater collected from the new gasoline

AST’s secondary containment area to the existing stormwater collection and infiltration basin

4. Magellan plans to begin construction in May 2019 and complete construction within 18 months.

Magellan’s actual construction dates are dependent on completion of the environmental review process and approval of permits required for the Project.

5. Magellan has submitted a permit application to the MPCA for reissuance of the Facility’s Permit for

Storage of Liquid Substances at a Major Above Ground Storage Tank Facility. Magellan must obtain this permit from the MPCA before the Project proceeds. The Project will also require additional approvals from state and local units of government.

Procedural History

6. An EAW is a brief document designed to provide the basic facts necessary for the Responsible

Governmental Unit (RGU) to determine whether an Environmental Impact Statement (EIS) is required for a proposed project or to initiate the scoping process for an EIS (Minn. R. 4410.0200, subp. 24). The MPCA is the RGU for this Project.

7. Minn. R. 4410.4300, subp. 10(B) requires preparation of an EAW for the Project because it is the

construction of a facility on a single site designed for or capable of storing 1 million gallons or more of hazardous materials.

8. The MPCA provided public notice of the Project as follows:

a. The Environmental Quality Board (EQB) published the notice of availability of the EAW for public comment in the EQB Monitor on January 7, 2019, as required by Minn. R. 4410.1500.

b. The EAW was available for review on the MPCA website at: www.pca.state.mn.us/eaw. c. The MPCA provided a news release to media in southern Minnesota, and other interested

parties, on January 7, 2019.

9. The MPCA held a public meeting about the Project in the city of Eyota on January 23, 2019.

10. During the 30-day comment period ending on February 6, 2019, the MPCA received comments on the EAW from the Minnesota Department of Natural Resources (MDNR), Minnesota Department of Transportation (MnDOT) and one citizen.

11. Comments received during the 30-day public comment period are included as Appendix A to these

Findings.

http://www.pca.state.mn.us/eaw


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12. The MPCA prepared written responses to the comments received during the 30-day public comment period. These responses are included as Appendix B to these Findings.

Criteria for Determining the Potential for

Significant Environmental Effects

13. The MPCA shall base its decision on the need for an EIS on the information gathered during the EAW process and the comments received on the EAW (Minn. R. 4410.1700, subp. 3). The MPCA must order an EIS for projects that have the potential for significant environmental effects (Minn. R. 4410.1700, subp. 1). In deciding whether a project has the potential for significant environmental effects, the MPCA must compare the impacts that may be reasonably expected to occur from the Project with the criteria set forth in Minn. R. 4410.1700, subp. 7. These criteria are:

A. Type, extent, and reversibility of environmental effects;

B. Cumulative potential effects. The RGU shall consider the following factors: whether the

cumulative potential effect is significant; whether the contribution from the project is significant when viewed in connection with other contributions to the cumulative potential effect; the degree to which the project complies with approved mitigation measures specifically designed to address the cumulative potential effect; and the efforts of the proposer to minimize the contributions from the project;

C. The extent to which the environmental effects are subject to mitigation by ongoing public

regulatory authority. The RGU may rely only on mitigation measures that are specific and that can be reasonably expected to effectively mitigate the identified environmental impacts of the project; and

D. The extent to which environmental effects can be anticipated and controlled as a result of other

available environmental studies undertaken by public agencies or the proposer, including other EISs.

The MPCA Findings with Respect to Each of These Criteria Are Set Forth Below

Type, Extent, and Reversibility of Environmental Effects

14. The first criterion that the MPCA must consider when determining if a project has the potential for significant environmental effects is the “type, extent, and reversibility of environmental effects” Minn. R. 4410.1700, subp. 7. A. The MPCA Findings with respect to this criterion are set forth below.

15. The types of environmental impacts that are reasonably expected to occur from the Project

include the following: · Surface water and groundwater quality · Spills · Groundwater appropriation · Air quality · Traffic


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16. Comments received during the EAW comment period raised the following additional

environmental issue: · Geologic hazards

17. With respect to the extent and reversibility of impacts that are reasonably expected to occur from

the Project, the MPCA makes the following Findings. Surface Water and Groundwater Quality 18. The Project will include construction of a 5 million gallon gasoline AST. The AST will not generate

wastewater during normal operation.

Construction Stormwater 19. The Project will result in the temporary generation of construction stormwater due to earthwork

activities associated with construction of the Project, such as excavating and grading.

20. A Minnesota Construction Stormwater General Permit (CSW Permit) is required when a project disturbs 1 acre or more of soil. This Project will disturb greater than 1 acre of soil; therefore, a CSW Permit is required for this Project. Magellan will apply for CSW Permit #MNR100001 for this Project. The CSW Permit will require Magellan to complete a Stormwater Pollution Prevention Plan (SWPPP). The SWPPP must propose erosion prevention and sediment control best management practices (BMPs) to control the discharge of sediment and/or other pollutants from the site.

21. Additionally, because the Project will result in land disturbance greater than 10,000 square feet,

Magellan is required to submit an Erosion Control and Runoff Plan to the Olmsted County Zoning Administrator for approval in accordance with the Olmsted County Zoning Ordinance (Section 10.20). The SWPPP and Erosion Control and Runoff Plan will include erosion prevention BMPs (e.g., temporary and permanent stabilization, stormwater diversion via ditches, sediment control BMPs (e.g., silt fence, berms), and other construction-related BMPs as required by the CSW Permit and Olmsted County Zoning Ordinance.

22. Also, as required by the CSW Permit’s Items 23.1 through 23.14, additional BMPs will be

implemented for areas of the Facility where construction stormwater may flow toward tributaries of South Fork Whitewater River which is impaired water for turbidity. These additional BMPs will include stabilizing exposed soils within 7 days of temporarily or permanently ceasing soil disturbance. In addition, when practicable, Magellan will leave a 50 foot undisturbed buffer around the identified wetlands during construction. If the construction requires encroachment upon the buffer, Magellan will install redundant (double) down gradient sediment control BMPs.

23. Construction stormwater is anticipated to primarily infiltrate into the ground; however, similar to

the Facility’s industrial stormwater discharges, during particularly wet periods, construction stormwater from the Facility may follow natural drainage courses through surrounding farm lands and along highway and railroad ditches to either an intermittent stream tributary to Bear Creek or intermittent streams tributary to South Fork Whitewater River.


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24. The CSW Permit for this Project also requires projects that create 1 acre or more of new

impervious surface to provide permanent treatment of stormwater runoff. This Project will create 1.7 acres of new impervious surface; therefore, permanent stormwater runoff treatment is required. The permanent treatment must control and treat 1 inch of runoff from each new acre of impervious surface created by the Project. Permanent treatment designs must first attempt volume reduction practices such as infiltration or harvest and reuse. If infiltration is not possible at the site due to poor soils, contamination, or other reasons outlined in the CSW Permit, other permanent treatment practices such as wet sedimentation basins or filtration systems are required. Magellan will use both the secondary containment area of its new AST as well as the Facility’s existing stormwater collection and infiltration basin to meet this stormwater collection and treatment requirement.

25. Proposed permanent stormwater management will be described further in the SWPPP and the

Erosion Control and Runoff Plan submitted to the Olmsted County Zoning Administrator for approval in accordance with the Olmsted County Zoning Ordinance (Section 10.20).

Industrial Stormwater

26. The Facility currently generates industrial stormwater from the water collected in its above ground

storage tank’s secondary containment areas as well as from impervious surfaces such as Facility roads. The Project will result in additional industrial stormwater being generated from the new gasoline AST.

27. Magellan is required to inspect industrial stormwater collected in its Facility’s existing AST’s

secondary containment basins for presence of a visible sheen prior to discharge. If a sheen is observed, the stormwater is routed through an oil/water separator prior to discharge; if no sheen is observed, stormwater is currently discharged to the ground surface. After implementation of the Project, if no sheen is observed, stormwater would be discharged to the Facility’s existing stormwater collection and infiltration basin. If the stormwater collection and infiltration basin were to overflow, the stormwater would flow to the wetland on the northeast side of the Facility site in the same manner as the Facility’s existing AST basins.

28. Industrial stormwater generated from the new AST’s secondary containment structure will be

managed in the same manner as the existing AST structures. Industrial stormwater generated from other areas of the Facility, such as roads, typically infiltrates into the ground. There is potential that, during particularly wet periods, stormwater may follow natural drainage courses through one of the identified wetlands and then through surrounding farm lands and along highway and railroad ditches to either an intermittent stream tributary to Bear Creek or intermittent streams tributary to South Fork Whitewater River.

29. During the occasions when stormwater leaves the Project site, the MPCA does not expect the

stormwater to contain significant pollutants due to Magellan’s permanent stormwater collection and infiltration basin, and the other BMPs within Magellan’s SWPPP. If problems occur, Magellan will develop improved BMPs.


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30. Industrial stormwater collected within the new AST’s secondary containment basin is expected to be similar in quality as the stormwater currently collected within the Facility’s existing tanks’ secondary containment basins.

Industrial Wastewater

31. The Project will result in the generation of additional industrial wastewater of two types:

petroleum contact water and hydrostatic test water.

32. Petroleum contact water means discharges from petroleum loading and transfer areas such as the truck loading bays, lab drain, and manifold piping. The addition of a third loading bay as part of this Project will result in an increase in the quantity of petroleum contact water collected from approximately 12,000 gallons per year to approximately 18,000 gallons per year. The composition of the additional petroleum contact water is expected to be consistent with the existing petroleum contact water collected from the loading bays.

33. After collection within sumps under the loading bays, loading bay petroleum contact water is pre-

treated through an oil/water separator and then temporarily stored in aboveground storage tank 339 at the Facility. Magellan contracts with West Central Environmental Consultants to transport the petroleum contact water stored in tank 339 to an off-site, licensed facility located in Fridley, Minnesota for treatment and disposal. The additional petroleum contact water from the third loading bay will be managed in a similar manner.

34. The Facility’s National Pollutant Discharge Elimination System/State Disposal System (NPDES/SDS)

Permit MN0059820 authorizes the discharge of hydrostatic test water used to test structural integrity of the Facility’s above ground storage tanks and onsite piping. Hydrostatic testing of the new AST and associating piping will require approximately 5 million gallons of water. After the hydrostatic test, if the hydrostatic test water is determined to comply with the effluent limits specified within the NPDES/SDS Permit, it may be discharged to the ground (outside of the containment areas and using controls to prevent erosion and scouring). Hydrostatic test water associated with this Project may either be discharged in accordance with the NPDES/SDS Permit or managed in another legal and authorized manner (for example, disposed of off-site or pumped back to the source).

35. With respect to the reversibility of surface water quality and groundwater quality impacts that are

reasonably expected to occur from the Project, if water quality impacts were to occur, they would be temporary, lasting during the storm event. Magellan then would modify the operation and management of the Project and the BMPs to reduce future impacts to waters Therefore, the water quality impacts that are reasonably expected to occur from the Project are found to be reversible.

36. The MPCA finds that information presented in the EAW and other information in the

environmental review record are adequate to assess potential impacts to the quality of surface water and groundwater quality that are reasonably expected to occur from the Project.


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37. The MPCA finds the Project, as proposed, does not have the potential for significant environmental effects based on the type, extent and reversibility of impacts related to surface water and groundwater quality, which are reasonably expected to occur.

Spills 38. The Project will include construction of a single 5 million gallon gasoline AST with associated piping

to transfer gasoline to the new truck load out bay.

39. The Facility is subject to the United States Department of Transportation (DOT) requirements including emergency response planning regulations found in 49 CFR 194 and hazardous waste spill planning requirements found in 49 CFR 265. The Facility has existing plans to comply with these requirements, which aim to minimize any unplanned release of hazardous waste that could result in potential threats to human health or the environment during design, construction, maintenance, and operation of the Facility.

40. The Facility is also subject to the U.S. Environmental Protection Agency’s (EPA’s) requirements to

prepare a Spill Prevention Control and Countermeasure (SPCC) Plan which meets the requirements found in 40 CFR 112. The Facility’s SPCC Plan outlines worst case spill planning, contracting with spill response organizations, and providing plans/coordinating with local first responders. Magellan is required to update its SPCC Plan as part of this Project.

41. Magellan will extend the Facility’s existing secondary containment berm to encompass the new AST.

The new berm will be approximately 6 feet high and will be designed to contain the volume of the new AST tank contents plus sufficient freeboard for precipitation (either 110% of the volume of the AST or the amount necessary for a 25-year, 24-hour storm, whichever is greater). The secondary containment area will be constructed with a minimum of 12 inches of compacted clay and have a maximum permeability rate of 1x10-7 centimeters/second. Magellan will perform soil percolation tests after clay compaction to verify the soil permeability rate. The results of the permeability testing will be certified by a registered professional engineer. In addition, a cover layer will be installed over the compacted clay to prevent its drying/cracking and erosion. The proposed AST’s secondary containment will conform to the standards in Minn. R. 7151.5400, subp. 5.

42. The new AST will be constructed to meet API Standard 650, Welded Tanks for Oil Storage, which is

incorporated by reference in Minn. R. 7151.2100, aboveground storage of liquid substances. The AST’s floor will be designed with a release prevention barrier (concrete ring wall with under tank leak detection and an impermeable synthetic material liner) consistent with API Standard 650 Appendix I and the Facility’s existing AST Permit number 50148.

43. Magellan will label the new AST with the substance stored, capacity, and a unique identification

number. 44. Magellan will apply a tank floor coating or liner, in accordance with API Standard 652, to protect

the topside of the AST floor. Magellan will install an impressed current cathodic protection system inside the ring wall and above the underfloor of the synthetic liner, in accordance with API Standard 651, to protect the underside of the AST’s floor.


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45. Magellan will design the new AST’s overfill protection system in accordance with the requirements of the Facility’s existing AST Permit and API Standard 2350.

46. Magellan will conduct maintenance activities on the new AST in accordance with API Standard 653,

the Facility’s AST permit requirements, and maintenance program requirements of DOT 195. Generally, API inspections will occur on a 5 to 20 year inspection cycle determined in accordance with inspector recommendations, Minnesota AST permit requirements, and API 653 Section 6.4.2.

47. If a spill over 5 gallons were to occur, Magellan will notify the Minnesota State Duty Officer and

comply with Minn. Stat. 115E. Magellan will respond to any spills as required in its Facility Response Plan, Emergency Response Action Plan, and SPCC Plan. Magellan will update its SPCC Plan, which incorporates the requirements of Minn. Stat. 115E Oil and Hazardous Substance Discharge Preparedness, to include the new AST and other Facility changes associated with the Project.

48. Drainage from the new (third) gasoline/diesel loading bay will flow into an oil-water separator with

an automatic overflow to a water tank designed to handle the single largest compartment of a tank car or tank truck (9,000 gallons).

49. The Facility has a SPCC Plan which meets the requirements found in 40 CFR 112. The Facility’s

plans outline worst case spill planning, contracting with spill response organizations, and providing plans/coordinating with local first responders.

50. The MPCA finds that any spills that occur would be either be captured by the new AST’s secondary

containment structure, or if it occurred in the loading day, would be captured in the bay’s sump and treated in its oil/water separator. These materials would then be re-introduced into the Facility or handled by appropriate waste disposal methods, such as removal to a treatment facility, or a disposal facility as described in the SPCC Plan.

51. With respect to the reversibility of impacts from spills from the Project, the MPCA finds that any

impacts that are reasonably expected to occur will be reversible due to the design, operation, and emergency response requirements that the Facility is subject to.


environmental review record are adequate to assess potential impacts of spills that are reasonably expected to occur from the Project.

53. The MPCA finds the Project, as proposed, does not have the potential for significant environmental

effects based on the type, extent and reversibility of impacts related to spills, which are reasonably expected to occur.

Groundwater Appropriation

54. There is currently a single water supply well at the Facility site (Unique Well ID 227374). The well is

used only for potable water and for restroom facilities. The well was constructed in 1966 and is registered with the Minnesota Department of Health.


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55. Magellan pumps less than 10,000 gallons of water per day and less than 1 million gallons of water per year from its existing well. This level of water use does not require a Water Appropriation Permit from the MDNR. Magellan does not plan to increase its water use from this well.

56. Magellan plans to construct one additional water supply well at the Facility site. The new well

would be approximately 700 feet deep and be in the Jordan Aquifer. The water from the new well would be used to conduct hydrostatic testing of the proposed new 5 million gallon gasoline AST. The well could also be used for future testing of other tanks at the Facility or for emergency response purposes.

57. The new well would have a maximum capacity of 285 gallons per minute and use a maximum of 5

million gallons of water per year. This level of water use from the new well requires a Water Appropriation Permit from the MDNR because it is over the permitting threshold of 10,000 gallons of water per day or 1 million gallons of water per year.

58. On September 17, 2018, Magellan applied to the MDNR for a Temporary General Water

Appropriation Permit (Permit No. 1997-005) and for a preliminary well assessment of the proposed well.

59. The MDNR is the permitting authority for appropriating waters of the state in Minnesota. The

MDNR Water Appropriations Permit allows for a reasonable use of water if the use does not negatively impact surrounding wells or other water resources.

60. The purpose of a MNDR Water Appropriation Permit is to ensure water resources are managed so

that adequate supply is available for long-range seasonal requirements for domestic, agricultural, fish and wildlife, recreational, power, navigational, and water quality.

61. The MDNR Water Appropriation Permit balances competing management objectives, including

both the development and protection of water resources. Minn. Stat. § 103G.261 establishes domestic water use as the highest priority use of the State’s water when supplies are limited. If a well interference arises, the MDNR has a standard procedure for investigating the matter. If the MDNR finds a commercial operator is causing interference, the operator must correct it.

62. Unauthorized pumping or use of the well or other water resources is subject to enforcement under

Minn. Stat. § 103. Upon completion of an investigation, a permit for water appropriation may be limited, amended, or denied in accordance with applicable laws and rules for the protection of the public interests and the sustainability of Minnesota’s water resources.

63. On November 30, 2018, the MDNR provided Magellan with preliminary approval to construct a

new water well at the Facility site. The MDNR’s approval indicated that the requested water appropriation is unlikely to have any impact on nearby calcareous fens (type of wetland), is expected to have a low potential for causing interference with nearby domestic water supply wells, and has a low potential for impacts to nearby streams.

64. Magellan will need to receive the Water Appropriation Permit from the MDNR before it can pump

water from the new well.


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65. Due to the MDNR oversight and permitting of water appropriations, the MPCA does not expect significant adverse impacts to water appropriation. However, if the MDNR determines there is well interference based on concerns or well interference claims, the operator must fix the causes of the interference. Thus, the impacts to water appropriations would then be reversed. The MPCA finds that any water appropriation impacts that may occur from the Project are reversible.


environmental review record are adequate to assess potential impacts to groundwater appropriation that are reasonably expected to occur from the Project.

67. The MPCA finds that the Project, as proposed, does not have the potential for significant

environmental effects based on the type, extent, and reversibility of impacts related to water appropriations that are reasonably expected to occur.

Air Quality

68. The Project will result in the addition of one 5 million gallon gasoline AST and a VRU at the Facility.

The VRU would be used to capture gasoline vapors from the Facility’s two existing and proposed new third tanker truck loading bay. The proposed new AST, VRU, and associated piping would be the major new sources of air emissions associated with the Project.

69. The Project’s new stationary air emission sources would result in the generation of the following

criteria air pollutants: volatile organic compounds (VOC). The Project would also result in the generation of the following hazardous air pollutants (HAPs): 2,2,4 trimethylpentane, benzene, ethyl benzene, hexane, toluene, and xylenes.

70. Magellan has applied for an Option 1 capped air emission state permit (Capped Permit) as allowed

under Minn. R. 7007.1140 to replace the Facility’s existing air emission permit. The Capped Permit will restrict the Facility’s potential air emissions to levels below federal permitting thresholds. The Capped Permit will also allow the Facility to make future changes as long as its actual air emissions levels remain below the Facility-wide Option 1 permit thresholds (90 tons per year for criteria pollutants, 9.0 tons per year for a single HAP, and 20 tons per year total for all HAPs).

71. Magellan currently operates under Synthetic Minor Air Emissions Permit No. 10900013-003. This

permit contains requirements to limit the Facility potential to emit (PTE) to levels below the major source thresholds (i.e., 100 tons per year) for Title V air permitting (40 CFR 70.2). Magellan’s new state capped permit will also require actual emissions to remain below Title V air permitting thresholds.

72. Magellan estimates that the Project will result in the following change in the levels of actual air

emissions at the Facility:


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Pollutant Pre-Project Actual Emissions (tons/year)

Post-Project Actual Emissions (tons/year)

Change (tons/year)

VOC 12.28 89.55 77.27 CO 5.7 1.34 -4.36 NOx 2.3 0.55 -1.75 2,2,4 Trimethylpentane 0.1 0.71 0.61 Benzene 0.11 0.8 0.69 Ethyl Benzene 0.01 0.09 0.08 Hexane 0.19 1.42 1.23 Toluene 0.16 1.15 0.99 Total Xylenes 0.06 0.44 0.38 Total HAPs 0.6 4.61 4.01

73. The Facility is currently a minor source under federal Prevention of Significant Deterioration (PSD)

regulations in 40 CFR 52.21 because the Facility-wide PTE is and will remain less than 100 tons per year for all regulated pollutants. The existing Facility’s air permit restricts the PTE of regulated PSD pollutants to less than 100 tons per year. After the Project, the Facility-wide emissions have the potential to be greater than 100 tons per year for VOC and the Facility would become a major PSD source. However, by applying for a capped permit, Magellan is proposing to maintain VOC emissions below the major source threshold and remain a minor PSD source.

74. The Facility’s proposed new gasoline AST will be subject to federal New Source Performance

Standards, specifically 40 CFR Part 60 Subpart Kb (Standards of Performance for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for which construction, reconstruction, or modification commenced after July 23, 1984). As such, the tank will be constructed with the controls that meet the emission control requirements specified in Subpart Kb. These emission controls include an internal floating roof equipped with dual rim-seals, guide-poles equipped with ‘no visible gap’ controls, and gaskets and bolts on other appurtenances as required by the regulation.

75. The Facility’s new gasoline/diesel truck loading bay, including the associated VRU and existing VCU,

is subject to 40 CFR Part 60, Subpart XX (Standards of Performance for Bulk Gasoline Terminals) that requires:

a. Operation of vapor collection equipment to collect VOC displaced from tank trucks during product loading

b. Emission limits from the vapor collection equipment (35 milligram (mg) VOC/Liter (L) gasoline loaded) which will be achieved with the VRU and backup VCU Vapor tightness certification for tank trucks

c. Pressure standards for pressure-vacuum vents on a vapor collection system d. Monthly inspections for equipment leaks

76. The proposed new VRU with the VCU backup will be subject to a more restrictive emissions rate to

reduce the air emissions below the 35 mg VOC/L gasoline loaded standard (40 CFR 60.502(b)), to 10 mg VOC/L gasoline loaded in order for the Facility to maintain actual emissions rates under the thresholds to qualify for an Option 1 capped air emission state permit.


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77. The Facility is currently subject to 40 CFR Part 63 Subpart BBBBBB National Emission Standards for Hazardous Air Pollutants (NESHAPs) for Source Category: Gasoline Distribution Bulk Terminals, Bulk Plants, and Pipeline Facilities; Subpart BBBBBB). Subpart BBBBBB is applicable to area (minor) source gasoline distribution bulk terminals and the Facility is, and will remain, an area (minor) source for HAPs. Subpart BBBBBB affected facilities include gasoline storage tanks, gasoline loading racks, and equipment leaks.

78. Subpart BBBBBB requires the Facility to reduce HAPs emissions to 80 mg VOC/L gasoline loaded

into cargo tanks and limit the loading of gasoline in cargo tanks demonstrated to be vapor tight (must be tested annually and meet a maximum allowable pressure/vacuum change of 3 inches of water in 5 minutes) using Reference Method 27 or equivalent. The proposed VRU will be designed to meet a more restrictive emissions rate of 10 mg VOC/L gasoline loaded in order for the Facility to meet the requirements for an Option 1 capped air emission state permit. The back-up VCU will continue to meet the 35 mg VOC/L standards of Subpart BBBBBB. All storage tanks used for the storage of gasoline are subject to Subpart BBBBBB gasoline storage vessel requirements. The tanks are required to meet the requirements of Table 1 of the Subpart – which includes installing a floating roof, and complying with the existing storage vessel requirements.

79. Subpart BBBBB also regulates fugitive emissions from piping components in gasoline service. This

equipment is inspected according to the provisions of 40 CFR 63.11089 requiring a monthly leak inspection of all equipment in gasoline service. Detection method is by sight, sound, and smell. A log book of all inspections is maintained at the Facility. Each detection of a liquid or vapor leak is recorded and repaired according to the timeline prescribed in 40 CFR 63.11089(c).

80. Magellan was required to conduct air dispersion modeling to demonstrate that the maximum

modeled concentrations for CO and NO2 meet all applicable standards. The NO2 and CO source at the Facility is the existing VCU which is being redesignated as a backup control device with the addition of a VRU with this Project. The EAW modeling was conducted with AERMOD (v16216r) and the MPCA processed 5 year AERMET dataset for Rochester, Minnesota.

81. The Project emission increases were modeled for comparison to the NO2 and CO Significant Impact

Levels (SIL). The results demonstrate that the Project’s CO air impacts are insignificant and the NO2

results required further analysis. NO2 did not pass the SIL, therefore the Project plus the existing Facility, nearby sources, and representative background concentrations were modeled and compared to the National Ambient Air Quality Standards (NAAQS).

82. Applying MPCA best practices from the “Air Dispersion Modeling Practices Manual” and available

tools, the nearby NOX sources were identified and a representative NO2 background concentration was selected for the 1 hour and annual NO2 NAAQS analysis. The VCU was modeled assuming it was operating at its full PTE hourly emission rate for 8,760 hours of the year for the 1 hour and annual average modeling analysis. In reality, the VCU will only be operational when the VRU is undergoing maintenance. NO2 is a pollutant that can be emitted both directly, but also form chemically in the atmosphere from the combination of NO emitted from a source and available ozone in the ambient air. For the NAAQS analysis, the EPA Tier 2 AERMOD option, ARM2, was selected which applies a default conversion ratio to the NOX emitted from that modeled sources. The MPCA modeling manual recommends a minimum ratio of 0.5 and a maximum of 0.9,


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therefore, those were the values entered in the model input files. The modeling was done to predict if the Facility would be in compliance with 1 hour and annual NO2 NAAQS. The modeling results demonstrated that the proposed Project would not exceed the NAAQS.

83. Magellan also quantified the quantity of air toxics emitted from the Facility’s storage tanks, tank

cleaning and landing activities, loading/unloading activities, equipment fugitives, and natural gas combustion. MPCA’s Risk Assessment Screening Spreadsheet (RASS) quantifies the potential acute health hazard, subchronic health hazard, chronic health hazard, and lifetime excess cancer risk from the Project’s emissions. Magellan completed the RASS using modeled maximum air concentrations from site specific AERMOD modeling for all pollutants in the RASS that are emitted from the post Project Facility.

84. The Air Emissions Risk Analysis (AERA) conducted for the Project included assessments for short

and long term exposures for both carcinogenic and non-carcinogenic outcomes and was found to be complete and technically accurate. The AERA results included a modeled benzene concentration that was above the chronic inhalation health benchmark. The largest contributor to the benzene concentration was the VCU. The VCU was modeled as a worst case operational scenario that results in an annual total facility emission rate of 152 tons per year. The currently permitted VCU is being replaced by a VRU with this permit action. The VRU has significantly lower VOC emissions (including benzene) than the existing VCU, such that operation of the VRU does not result in a modeled result above inhalation health benchmarks. Magellan’s current operational plan includes the VRU in continuous use and the VCU in place as a back-up unit. Without specific permit conditions requiring the VRU as primary operation, the MPCA confirmed the Facility will need to operate the VRU or proportionally curtail throughput to comply with the capped permit annual VOC emission limit of 90 tons per year. Reporting requirements for the emission estimates of the Facility are annual. Furthermore, the lower VRU emissions of VOCs will be confirmed by performance testing. Due to this additional information from the proposed and approved permitting structure, the air toxics emissions for the Facility are likely to result in air concentrations below all inhalation health benchmarks.

85. With respect to the reversibility of air quality impacts that are reasonably expected to occur from

the Project, air emissions would continue while the Facility remains in operation, and would cease only if the equipment associated with the Project were to be taken out of operation (including removal of gasoline from the AST and associated piping). The MPCA finds that any air quality impacts that may occur from the Project are reversible.

86. The MPCA finds that the information presented in the EAW and other information in the

environmental review record is adequate to assess potential impacts to air quality that are reasonable expected to occur from the Project.


environmental review record is adequate to address the concerns related to air emissions. The impacts of air emissions that are reasonably expected to occur from the proposed Project have been considered during the review process and methods to prevent significant adverse impacts have been developed.


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88. The MPCA finds the Project, as proposed, does not have the potential for significant environmental effects based on the type, extent, and reversibility of impacts on air quality that are reasonably expected to occur from the Project.

Traffic 89. The Facility currently has a single vehicle access point at Minnesota State Highway 42 which is on

the east side of the site. Highway 42 includes turn lanes to avoid impeding other traffic. The Project will not result in any additional access points or changes to this or any other nearby roads.

90. The Facility currently receives approximately 100 tanker trucks per day. The Project will result in an

approximate increase of 15 additional tanker trucks per day.

91. According to MnDOT, average annual daily traffic (AADT) is 3,150 vehicles at Highway 42 and 5,300 vehicles at U.S. Highway 14. The additional vehicle trips associated with the Project will result in an approximately 1% increase in truck traffic on these roads.

92. With respect to the reversibility of traffic impacts that are reasonably expected to occur from the

Project, the MPCA finds that if the Project were to cease operation, traffic levels to and from the Facility would return to pre-Project levels. The MPCA finds that any traffic impacts that may occur from the Project are reversible.


environmental review record is adequate to address the concerns related to traffic. The impacts from traffic that are reasonably expected to occur from the proposed Project have been considered during the review process and methods to prevent significant adverse impacts have been developed.


effects based on the type, extent and reversibility of impacts related to traffic, which are reasonably expected to occur.

Public Comments on Impacts Related to Geologic Hazards 95. According to the Geologic Atlas of Olmsted County (Plate 3), surficial geology at the Project site

consists of till, described as an “unsorted, unstratified drift deposited by a glacier; a mix of sand, silt, and clay (typically loam to clay loam).” Depth to bedrock at the Facility is less than 50 feet, as mapped in Plate 2 of the Geologic Atlas of Olmsted County. Stratigraphy reports from the Minnesota Well Index indicate till, consisting primarily of clay, overlies the bedrock. The commercial water well at the Facility (Unique ID 227374) extends 288 feet in depth and terminates in the St. Peter Sandstone Aquifer. The stratigraphy log from this well indicates bedrock lies 22 feet below the ground surface.

96. The uppermost bedrock at the Facility is the Prosser Formation, a thin-bedded limestone and

dolomite layer that is part of the Galena Group, or Upper Carbonate Aquifer. The Prosser Formation and underlying Cummingsville Formation, a fine-grained limestone with calcareous


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shale, comprise the Upper Carbonate Aquifer and total approximately 130 feet in thickness. The Decorah, Platteville, and Glenwood Formations, a group of limestones and shales, underlie the Upper Carbonate Aquifer for approximately 70 feet, followed by 100 feet of the St. Peter Sandstone.

97. No surface karst features (sinkholes or springs) have been identified at the Project or Facility site

over the 50 years of operation. The nearest karst feature is a sinkhole located 0.96 miles southwest of the Project site. The Facility site has low to moderate probability of sinkholes due to the carbonate bedrock beneath the surficial till layer.

98. Low permeability clay and silt soils are present above the bedrock layer. This surficial till layer

results in a lower sensitivity to pollution transport than other locations in Olmsted County, with estimated contamination travel times in the range of several years to a decade.

99. A geotechnical study conducted by Kleinfelder in October 2017 corroborated geologic data

obtained from the Geologic Atlas of Olmsted County and confirmed there are no surface karst features present at the Project site. The study, which consisted of seven borings, found sand and clay glacial soils underlain by limestone bedrock. Depths to bedrock observed in the soil borings range from 19 to 35 feet.

100. Groundwater was observed in only one boring (ST-B-1) at a depth of approximately 28 feet.

Perched water was observed in Boring LT-B-3 at a depth of approximately 20 feet. The study concluded the proposed AST can be constructed using conventional grading and construction techniques. The AST will also include a secondary containment structure as required by Minnesota Pollution Control Agency (MPCA) regulations to contain 110% of the volume of the new AST. This will mitigate the potential for any release from the AST reaching the ground or sub-surface geology.

101. Magellan does not plan to construct the tank or other components directly on or in contact with

bedrock. However, in the unlikely event that structures will be constructed directly on or in contact with bedrock, exploratory probes will be conducted to check for voids and cavities. In the event that voids or cavities are found, Magellan’s geotechnical consultant has indicated that standard construction practices in the karst region will be followed, such as removing the bedrock around the void and filling the void with rock and concrete such that a solid base is formed and the void eliminated.


environmental review record is adequate to address the concerns related to geologic hazards of the Project. Impacts to geology that are reasonably expected to occur from the proposed Project have been considered during the EAW process and methods to prevent significant adverse impacts have been developed.

103. The MPCA finds that the geologic risks of the Facility site have been adequately assessed in the

EAW and response to comments and appropriate design and operational requirements will be taken into account for karst. The Facility’s AST and other structures will not be located on or next


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to any known sinkholes. The AST has been designed to prevent spills from occurring and capture and contain them in the event that one did occur.


effects based on the type, extent and reversibility of impacts related to geology, which are reasonably expected to occur.

Cumulative Potential Effects

105. The second criterion that the MPCA must consider when determining if a project has the potential

for significant environmental effects is the “cumulative potential effects.” In making this determination, the MPCA must consider “whether the cumulative potential effect is significant; whether the contribution from the project is significant when viewed in connection with other contributions to the cumulative potential effect; the degree to which the project complies with approved mitigation measures specifically designed to address the cumulative potential effects; and the efforts of the proposer to minimize the contributions from the project.” Minn. R. 4410.1700 subp.7.b. The MPCA Findings with respect to this criterion are set forth below.

106. The EAW, public comments, and MPCA follow-up evaluation did not disclose any related or

anticipated future projects that may interact with this Project in such a way as to result in significant cumulative potential environmental effects.

107. The EAW addressed the following area for cumulative potential effects for the proposed Project:

Air Quality

108. The MPCA considered the cumulative potential effects for the Project on air quality. This analysis included consideration of background concentrations for the area and the impacts from the Project. The MPCA makes the following findings on the cumulative potential effects for the Project on air quality.

109. Operation of the Project will generate air emissions. Magellan conducted air dispersion modeling

to evaluate cumulative effects. This evaluation considered background conditions and the Project impacts. See Findings 80 through 85 above. Based on the modeling, the MPCA expects that the anticipated increase in air emissions will not result in significant cumulative potential effects.

Cumulative Effects – Summary 110. Based on information on the Project obtained from air modeling, permit application processes,

information presented in the EAW, and consideration of potential effects due to related or anticipated future projects, the MPCA finds no potential for significant cumulative effects from the Project.


effects related to cumulative potential effects that are reasonably expected to occur.


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The Extent to Which the Environmental Effects Are Subject to Mitigation by Ongoing Public Regulatory Authority

112. The third criterion that the MPCA must consider when determining if a project has the potential for significant environmental effects is "the extent to which the environmental effects are subject to mitigation by ongoing public regulatory authority. The RGU may rely only on mitigation measures that are specific and that can be reasonably expected to effectively mitigate the identified environmental impacts of the project." Minn. R. 4410.1700, subp. 7.C. The MPCA Findings with respect to this criterion are set forth below.

113. The following permits or approvals will be required for the Project:

Unit of Government Permit or Approval Required MPCA Capped Air Emission State Permit (Option 1)

NPDES/SDS Permit MN0059820 (Modification) 2018 NPDES/SDS General Construction Stormwater Permit #MNR1000001 Aboveground Storage Major Facility Permit #50148 (Reissuance) Prevention and Response Plan (Incorporated within SPCC Plan)

EPA SPCC Plan MDNR Water Appropriation Permit - Temporary Projects General Permit 1997-0005

(Construction Dewatering and Hydrostatic Testing) Olmsted County Erosion Control and Runoff Plan Review

Conditional Use Permit (CUP) Olmsted County Emergency Response Plan Review

Eyota Township CUP Application Review

114. MPCA Capped Air Emission State Permit – Option 1. Magellan must receive an air emission permit from the MPCA before Project construction can begin. The permit will contain operational and air emission limits, including requirements for use of air pollution control equipment, that will help prevent or minimize the potential for significant environmental effects from the Project.

115. MPCA NPDES/SDS Permit MN0059820. Magellan must receive a modification of its NPDES/SDS

permit before it can discharge any wastewater associated with the Project. The NPDES/SDS permit will contain wastewater testing and pollutant discharge limits that will help prevent or minimize the potential for significant environmental effects from the Project.

116. MPCA 2018 NPDES/SDS General Construction Stormwater Permit #MNR1000001. Magellan must

receive a construction stormwater permit for the Project. The CSW Permit will require Magellan to complete a SWPPP. The SWPPP will contain erosion prevention and sediment control BMPs to control the discharge of sediment and/or other pollutants from the site, which will help prevent the potential for significant environmental effects from the Project.

117. MPCA Aboveground Storage Major Facility Permit #50148. Magellan must receive an AST permit

before it starts construction of its proposed new gasoline tank. The purpose of this permit is to prevent pollution to the waters of the state, including surface waters and groundwater, by leaks and spills of liquid substances from AST systems located at the Facility, through implementation of appropriate release prevention, detection, and containment measures.


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118. MPCA Prevention and Response Plan. Magellan must update its Prevention and Response Plan. The plan outlines worst case spill planning, contracting with spill response oganizations, and providing plans/coordinating with local first responders. The plan will be incorporated into the Facility’s SPCC Plan.

119. EPA SPCC Plan. Magellan must update its SPCC Plan to reflect the Facility changes associated with

the proposed Project. The plan outline worst case spill planning, contracting with spill response oganizations, and providing plans/coordinating with local first responders.

120. MNDR Water Appropriation Permit - Temporary Projects General Permit 1997-0005. Magellan

must receive its water appropriations permit from the MDNR before it begins pumping any water from its new well or conducting any dewatering necessary at the construction site.

121. Olmsted County Approvals. Magellan must obtain approval for a CUP, Erosion Control and Runoff

Plan, and Emergency Response Plan from Olmsted County. The CUP will address local zoning, environmental, regulatory, and other requirements needed to avoid adverse effects on adjacent land.

122. Eyota Township CUP Application Review. Magellan must submit its Olmsted County CUP

application to Eyota Township for review. 123. The above-listed permits/approvals include general and specific requirements for mitigation of

environmental effects of the Project. The MPCA finds that the environmental effects of the Project are subject to mitigation by ongoing public regulatory authority.

The Extent to Which Environmental Effects can be Anticipated and Controlled as a Result of Other Available Environmental Studies Undertaken by Public Agencies or the Project Proposer, Including Other EISs 124. The fourth criterion that the MPCA must consider is “the extent to which environmental effects

can be anticipated and controlled as a result of other available environmental studies undertaken by public agencies or the project proposer, including other EISs,” Minn. R. 4410.1700, subp. 7.D. The MPCA Findings with respect to this criterion are set forth below.

125. The MPCA reviewed the following documents as part of the environmental impact analysis for the

Proposed Project: · Data presented in the EAW · AST permit application · Air quality permit application · Air dispersion modeling report · Facility’s current NPDES/SDS permit (industrial wastewater permit) · Kleinfeld’s Geotechnical Study of the Facility (October 2017) · Permits and environmental review of similar projects

126. This list above is not meant to be exhaustive. The MPCA also relies on information provided by Magellan, persons commenting on the EAW, staff experience, and other available information obtained by staff.

APPENDIX A

Minnesota Pollution Control Agency

Magellan Rochester Terminal Expansion Project

Environmental Assessment Worksheet (EAW)

LIST OF COMMENT LETTERS RECEIVED 1. Jan Blevins, Email received, February 5, 2019. 2. Rebecca Horton, Minnesota Department of Natural Resources, Email with comment letter received,

February 5, 2019. 3. Heather Lukes, Minnesota Department of Transportation, Letter received, February 6, 2019.

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Minnesota Department of Natural Resources • Ecological and Water Resources 1200 Warner Road, St. Paul, MN 55106

February 5, 2019

Steve Sommer Project Manager 520 Lafayette Road North St. Paul, MN 55155

RE: Magellan Rochester Terminal Expansion EAW

Dear Steve Sommer,

The Minnesota Department of Natural Resources (DNR) has reviewed the Environmental Assessment Worksheet (EAW) for the Magellan Rochester Terminal Expansion Project. Regarding matters for which the DNR has regulatory responsibility or other interests, we offer the following comments for your consideration.

The Magellan Terminal is built on karst. Provided the nature of the project, and the karst environment, the DNR has concerns that new sinkholes could form, and that groundwater contamination could occur as a result of the project. DNR groundwater specialists reviewed the project location and EAW, and provided comments in the attachment (enclosed). The DNR recommends that these comments be considered to ensure that the project is developed in an appropriate manner so as to not cause pathways for contaminants to reach the groundwater.

With concern for water contamination in mind, the EAW states that industrial stormwater is inspected for the presence of visible sheen prior to discharge. Please describe how the site is configured so the industrial stormwater from the facility’s tank’s secondary containment area can be isolated to prevent water with a visible sheen going directly to the stormwater infiltration basin? What unique design allows the facility to control when water is routed through the Facilities oil/water separator before being discharged to the ground? Is there a redundant BMP control a bypass valve that will be installed with the new underground piping?

Pages 16 - 17: noted “Industrial stormwater generated from other areas of the Facility, such as roads, typically infiltrates into the ground. There is potential that, during particularly wet periods, stormwater discharged from the Facility may follow natural drainage courses through one of the identified PEMC wetlands and then through surrounding farm lands and along highway and railroad ditches to either an intermittent stream tributary to Bear Creek or intermittent streams tributary to South Fork Whitewater River”. The DNR recommends that additional/redundant BMPs be installed to prevent stormwater from leaving the facility and entering nearby waters.

Water Appropriations Permits:

• Magellan has applied for two DNR General Permits for Temporary Appropriation. These DNR WaterAppropriation Permits are required for construction dewatering that exceeds 10,000 gallons per day, orone million gallons per year, that is associated with the construction of the new AST, grading,installation of utilities, storm water facilities, vapor recovery unit, MMC, or road improvements.

• The use of more than 10,000 gallons of water per day, or one million gallons per year, for thehydrostatic testing of tanks or pipelines must be approved under a DNR Water Appropriation Permit.DNR General Permits for Temporary Appropriation are issued for periods of time that do not exceed oneyear in length.

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Minnesota Department of Natural Resources • Ecological and Water Resources 1200 Warner Road, St. Paul, MN 55106

• Magellan has also received a medium risk letter for the Well Construction – Preliminary Assessment File 2018-3446 for the new well.

On behalf of the DNR, thank you for consideration of these comments.

Sincerely,

/s/ Rebecca Horton Region Environmental Assessment Ecologist CC: Scot Johnson (Groundwater Specialist), Nicole Lehman (Area Hydrologist), Joe Richter (Appropriations Hydrologist) Attachments: MagellanRochesterEAW-GroundwaterSpecialis Comments.pdf

Magellan Rochester Terminal Expansion Project EAW Comments

John Barry, Hydrogeologist, DNR County Geologic Atlas Mapping Program

Scot Johnson, Groundwater Specialist, DNR Groundwater Technical Analysis Work Group

12/18/2018

DRAFT EAW Questions 10 and 11. Geology, soils, and topography/land forms and Water resources:

Geologic mapping and characterization, groundwater level response, dye tracing in the project vicinity, geophysical investigation results, and site-specific boring logs collected at the nearby site of a proposed ethanol plant illustrate that the Magellan Terminal is built on karst. EAW Figure 10 shows that the terminal location is on karsted bedrock.

The first bedrock unit in the vicinity is the Prosser Formation of the Galena Group. The Galena Group is well characterized as karst in Minnesota (Alexander and Lively, 1995; Alexander et al., 1996; Green et al., 1997, 2002; Runkel et al., 2003, 2014). Dendritic drainage patterns, shallow depth to soluble bedrock, and nearby sinkhole clusters and springs highlight the terminal vicinity as karst. Sinkholes have been mapped in the Prosser Formation within 1-mile of the proposed above ground storage tank.

The majority of wells in the immediate vicinity of the terminal show depth to bedrock in the thirty feet or less range. Two wells on-site, 558143 and 227374, log the depth to bedrock at 14 feet and 22 feet respectively. The 19 to 35 feet range of depth to bedrock reported from the tank site soil borings suggest a highly weathered karst bedrock surface. Material descriptions of the Prosser from boring logs collected at the site of a proposed ethanol plant roughly 3,500 feet south of the terminal by American Engineering Testing noted depth to the Prosser in the 10-20 foot range with fracturing described as very fractured to moderately fractured (AET, 2008).

Field-verified karst features, such as sinkholes, are direct evidence that karst processes are active both on the surface and in a karst aquifer in the subsurface. However, although there are no sinkholes on the land surface at the terminal location, this does not imply the absence of karst processes at land surface or karst hydrology in the subsurface. At a Prosser Formation quarry located roughly 1.6 miles west of the project area, vertical staining within exposed quarry walls illustrates surface water-groundwater pathways common in the Prosser Formation karst (Figure 1). Surface karst features are likely not expressed at the terminal because the Browerville till at the project site is slightly thicker than the other surrounding surficial materials and more effectively masks the subsurface karst.

Karst is well known for heterogeneity in geologic and hydrologic conditions over short distances. Therefore, thorough and detailed geologic investigations in karst should go beyond standard site characterization using soil borings and use geophysical techniques (Tennessee Department of Environment and Conservation, 2014).

Karst Concerns Magellan is proposing to expand the existing facility by constructing a field-erected, 5-million-gallon above-ground storage tank for additional gasoline storage and offloading capacity. Construction includes containment berms around the tank and underground containment drainage to a stormwater basin. Infiltration of stormwater in karst settings requires special considerations (MPCA, 2018).

Infiltrating large quantities of water in this geologic setting may increase the probability of sinkhole formation. Additionally, pollutants being carried by stormwater runoff in this setting may pass rapidly through the subsurface into groundwater. Increased impervious area within the facility footprint will increase volumes routed to the stormwater basin, increasing the potential for sinkhole development and rapid movement of contaminated stormwater into the Galena aquifer below. The Galena aquifer in the project vicinity responds very rapidly to recharge events, highlighting its connectivity to the land surface (Figure 2).

In addition, once filled with gasoline, the new storage tank will be quite heavy which requires assurances that the bedrock and construction fill materials be stable and not subject to subsidence. Due to the underlying karst, the geology underlying the containment structure should be thoroughly characterized to ensure that no voids or preferential pathways exist in the proposed location. Recommended additional information needed to make the EAW complete

1. The seven borings used to characterize the Magellan Terminal site are insufficient to fully characterize the karst setting. However, the soil boring may be valuable in designing and interpreting future on-site investigations. The soil borings should be labeled in EAW Figure 7 and the soil borings logs should be provided in EAW Appendix A.

2. The soil borings should be supplemented with surface geophysical characterization of the site

using electrical resistivity transects, gravity, and/or other surface geophysical methods to adequately characterize karst conditions at the terminal site. Bedrock anomalies detected by the surface geophysics may require exploratory soil borings to characterize and interpret them.

3. Additional details regarding the relationship of the grading, excavation and filling with gravel and clay to the karst bedrock below is needed. This should be shown on grading plan sheets and cross sections. The above-ground tank’s foundation design, testing and workflow should be described in more detail.

4. The Minnesota Springs Inventory shows spring and seep locations near the project location. Content related to springs and seeps should be added to the answer to EAW Question 11. The location of springs should be added to EAW Figure 10.

Figure 1. Quarry located approximately 1.6 miles west of the Magellan Eyota Terminal. Groundwater level response of a nearby Galena well shows rapid recharge characteristics consistent with karst (Figure 2). In addition, dye tracing within 5 miles of the terminal location has shown rapid groundwater velocities consistent with karst (Larsen, 2016; Barry, 2018).

Figure 2. Groundwater level of Galena well (817784), located approximately 3.6 miles southwest of the Magellan Eyota Terminal. .

Comment References

American Engineering Testing, 2008, Report of the Geotechnical Exploration and Review: Proposed Ethanol Plant, Eyota, Minnesota. Alexander, E.C., Jr., and Lively, R.S., 1995, Karst-aquifers, caves and sinkholes, in Lively, R.S., and Balaban, N.H., eds., Text supplement to the Geologic Atlas, Fillmore County, Minnesota: Minnesota Geological Survey County Atlas Series C-8, Part C, p. 10-18. Alexander, E.C., Green, J.A., Alexander, S.C., and Spong, R.C., 1996, Spring sheds, Plate 9, in R.S. Lively and N.H. Balaban, eds., Geological Atlas of Fillmore County, Minnesota: Part B, County Atlas Series published by the Minnesota Department of Natural Resources, Division of Waters. Barry, John D; Overbo, Alycia K; Green, Jeffrey A; Larsen, Martin R; Alexander, Scott C; Alexander Jr., E Calvin. (2018). Springdale Dye Trace Report Olmsted County, Minnesota 2017 Dye Trace Report. Retrieved from the University of Minnesota Digital Conservancy, http://hdl.handle.net/11299/200689.

Green, J.A., Alexander, E.C. Jr., Marken, W.G., and Alexander, S.C., 2002, Karst Hydrogeomorphic units, pl. 10 of Falteisek, J., ed., Geologic atlas of Mower County, Minnesota: Minnesota Department of Natural Resources, Division of Waters County Atlas C-11, pt. B, scale 1:100,000. Green, J.A., Mossler, J.H., Alexander, S.C., and Alexander, E.C., Jr., 1997, Karst Hydrogeology of Le Roy Township, Mower County, Minnesota, Minnesota Geological Survey Open File Report 97-2. 2 Plates, Scale 1:24,000. Larsen, Martin R; Green, Jeffrey A; Wheeler, Betty J; Kasahara, Sophie M; Alexander Jr., E. Calvin. (2016). Groundwater Tracing in Orion, Marion and Eyota Townships of Olmsted County, Minnesota. Retrieved from the University of Minnesota Digital Conservancy, http://hdl.handle.net/11299/184776.

Minnesota Pollution Control Agency, 2018, Minnesota Stormwater Manual webpage, last updated August 17, 2018. https://stormwater.pca.state.mn.us/index.php?title=Karst.

Runkel, A.C.; Tipping, R.G.; Alexander, E. Calvin, Jr.; Green, Jeffrey A.; Mossler, J.H.; Alexander, S.C.. (2003). RI-61 Hydrogeology of the Paleozoic bedrock in southeastern Minnesota. Minnesota Geological Survey. Retrieved from the University of Minnesota Digital Conservancy, http://hdl.handle.net/11299/58813.

Runkel, Anthony C.; Steenberg, Julia R.; Tipping, Robert G.; Retzler, Andrew J.. (2014). OFR14-02, Geologic controls on groundwater and surface water flow in southeastern Minnesota and its impact on nitrate concentrations in streams. Minnesota Geological Survey. Retrieved from the University of Minnesota Digital Conservancy, http://hdl.handle.net/11299/162612.

Tennessee Department of Environment and Conservation, 2014, Appendix B: Stormwater Design Guidelines for Karst Terrain, http://tnpermanentstormwater.org/manual/27%20Appendix%20B%20Stormwater%20Design%20Guidelines%20for%20Karst%20Terrain.pdf.

http://hdl.handle.net/11299/200689

http://hdl.handle.net/11299/184776

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APPENDIX B


Magellan Rochester Terminal Expansion Project

Environmental Assessment Worksheet (EAW)

RESPONSES TO COMMENTS ON THE EAW 1. Comments by Ms. Jan Blevins. Email received February 5, 2019. Comment 1-1: Commenter expressed concern regarding the Project’s impacts on quality and quantity of water in private wells and aquifers in the project area. The commenter stated, “Reference to Minnesota Statues 103G.287 Groundwater This statute must be strictly adhered too. Established water levels must be maintained, along with water quality that will protect our ecosystems and the future generations to meet their needs regarding drinkable and obtainable water. I request that a baseline for water quality and quantity is established via water testing and water level measuring of the surrounding wells within a mile of this proposed site. Testing for gasoline range organics, diesel range organics which include hydrocarbons. Reasoning: If wells become contaminated, the private well owners will have some verification that this project contributed to the contamination which would require that Magellan would be responsible for providing them with a new well based on Minnesota Law at no cost to the well owner. During such time they (the families and farms in the area) have no clean water to drink Magellan would provide families and farm operations with clean water as needed at no cost to the families impacted. Any change in water quantity or quality (based on testing) that impacts a family within this area should require immediate action immediately to correct the situation. This may be a new well and/or equipment that would provide a filtering systems for potable water a drinking water source while the loss of water quantity or quality is corrected. If Magellan is successful in their request the DNR should be required to monitor wells during the drilling and use of the proposed well to be certain that they are not changing the flow of the aquifers above their target aquifer and also have not caused a private well owner to lose their supply of water in their well.” Response: Regarding groundwater quantity, the Minnesota Department of Natural Resources (MDNR) is the responsible governmental unit for issuing water appropriation permits. Minnesota Statues 103G.287 allows the MDNR to issue water appropriation permits only if they determine that the groundwater use is sustainable. The MDNR conducted a preliminary well assessment for Magellan’s well and concluded the well is unlikely to have any impact on the Dover calcareous fens, potential for domestic well interference appears low, and that potential for impacts to the two nearest MDNR public waters appears low (EAW Appendix B). In addition, the MDNR informed Magellan that if the use of the proposed well deprives nearby homes of their domestic water supply as a result of a valid well interference complaint(s) that is affirmed by the MDNR, then use of the well must stop until Magellan establishes a new water supply for the affected homes. EAW, item 11.b.iii. provides additional information regarding the Magellan’s proposed water appropriation. Regarding groundwater quality, the EAW provided information regarding previous investigations that have been completed at the Facility site to determine if there has been any historical groundwater contamination. As indicated in item 12.a. of EAW, these studies did not find evidence of soil or groundwater contamination at the Facility site. Further, the Project would result in construction of a 5 million gallon gasoline above ground storage tank (AST). This size gasoline tank requires a major AST

Magellan Rochester Terminal Expansion Project Responses to Comments on the Eyota Township, Minnesota Environmental Assessment Worksheet

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permit from the MPCA before it may be constructed. The AST permit contains design, construction, and operation requirements to minimize any releases and emergency response requirements in case a release occur (see item 12 of EAW for details). These requirements protect against contamination of groundwater and nearby wells.

With respect to the request for a baseline study of groundwater availability and quality, this request is beyond the scope of the EAW. Comment 1-2: Commenter stated, “With our aquafers not regenerating and at rate that will sustain our water supply I question DNR’s decision to allow a pump and dump of 5 million gallons of our drinking water to just test a tank. ‘Freshwater’ is presently looking at conducting a study in regard to groundwater recharge for the southeastern Minnesota region and perhaps this well permit should be on hold until we know what impact this will have on our drinking water supply for the community and what impact this new well will have. SE Minnesota is one of the areas that have declining groundwater levels. Groundwater is being used faster than it is being replenished by precipitation.” Response: Please see response to comment 1-1. Comment 1-3: Commenter requested the following, “Test the soil surrounding the tank farm for pollution as a baseline. This would be to consider existing conditions and to watch for any impact the activity during construction and tank farm usage would have on the wetlands on our property. Our property includes a Calcareous Fen which was discovered by Jeanette Leete with the DNR when the ethanol plan was being considered. It is not registered but should be. We do not want this negatively impacted by pollution and too much draw from the well which would impact the ground water supply. This fen is slated to be refurbished in the future and we had discussed this with the DNR at a trail meeting.” Response: Previous studies of the Facility site have not detected soil contamination. Also as indicated in response to comment 1-1, the MDNR assessed the potential impact of Magellan’s well on known calcareous fens in the Project area (Dover 13 and Dover 7) and determined that a single well pumping for 14 days and more than 2 miles away is unlikely to have an impact on the Dover calcareous fens. The MDNR’s review did not indicate that there are any calcareous fens on your property, however the EAW contains sufficient information to evaluate the Project’s effects on nearby surface waters, including wetlands. Comment 1-4: Commenter requested the following, “Require that the pipeline feeding this tank farm has been thoroughly tested to be certain it can handle the additional pressure and the increased flow and share those results with the community and neighbors. You stated that this was not part of the project but it is under the phased and connected actions.” Response: The Project does not include increasing the maximum allowable operating pressure or capacity of the existing mainline pipeline that supplies gasoline to the Facility. Therefore, the operation of the pipeline is not a connected or phased action. Magellan adheres to pipeline safety regulations as administered by the Minnesota Office of Pipeline Safety and U.S. Department of Transportation Pipeline Hazardous Materials Safety Administration.


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Comment 1-5: Commenter stated the following, “I request that you verify that the products that are going into this 5 million gallon tank are going to be used nearby. It is my understanding from some haulers that they haul into Iowa and up to the Twin Cities. In order to prevent more traffic and pollution at this site this product should be piped to those areas rather than hauled via truck transport. This would mean they do not need this large of tank at this site. Consider reduction of the tank size so that it lessons all hazards of increased traffic for the community.” Response: The purpose of the Project is to increase the terminal’s overall efficiency, storage capacity and truck-loading capabilities to meet Magellan’s customers’ needs for additional gasoline supply in southeastern Minnesota, northeastern Iowa, and southwestern Wisconsin. Magellan has refined products terminals in other locations within Minnesota and Iowa, including the Minneapolis/St. Paul area that provide regional trucking companies access to refined products while reducing travel distances to their desired locations. Comment 1-6: Commenter stated the following, “I request that you reduce the size of this 5 million gallon tank to a size that would be safer for this community and the HazMat team and fire departments would have the capability of extinguishing a fire with foam if such a catastrophe happened. It is my understanding that there isn’t enough foam in Southern Minnesota to put this size of fire out per the Rochester HazMat team that was attending your meeting. This leaves the community with evacuation concerns, air pollution, health risks, and many other undesirable impacts.” Response: Minnesota’s EAW rules (Minn. R. 4410) do not provide the preparer of an EAW (i.e., the Responsible Governmental Unit) with the authority to dictate the size of a proposed project. The EAW process assesses a proposed project’s potential for significant environmental effects and informs the permit process. In response to your concern regarding fire catastrophes, Magellan has existing plans (Spill Prevention Control and Countermeasure, Facility Response Plan) that are required by the AST permit which include mandatory coordination with local first responders. It also has agreements with specialized contractors to provide support in the event of an emergency. In the unlikely event of a tank fire, those specialized contractors, which include petroleum fire-fighting experts as well as toxicologists and air quality experts, are equipped to quickly respond and provide the necessary resources and support from across the nation. In addition, Magellan is in discussions with the local first responders to help ensure availability of fire-fighting equipment. Comment 1-7: Commenter stated the following, “Prior to this tank being constructed the community should be aware of the risks and require that there is a plan in place shared with the community and neighborhood for housing evacuated citizens and many other considerations.” Response: The EAW provided information regarding potential environmental risks of the Project and a pubic meeting was held on January 23, 2019, to provide meaningful community engagement about this proposed Project. Comments regarding fire safety are outside the scope of the EAW. Please contact the city of Eyota Fire Chief regarding any questions on this issue.


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Comment 1-8: Commenter stated the following concerns regarding hydrostatic testing, “The amount of water being drawn in this 14 day period to test the tank could impact both the wetlands, streams and the springs that feed the Whitewater River. With all the well drilling that has occurred in this area the springs and streams have disappeared. There were many trout streams that are now gone because DNR has approved so many wells without really knowing what they have to give out. Provide a plan for how the wetlands, streams and ground water adjacent to the area will be protected not only during this water draw and release but future activities that may impact these areas.” Response: As indicated in response to comment 1-1, the MDNR has completed a preliminary well construction assessment for the Project’s proposed well. The MDNR’s assessment did not reveal any anticipated significant impacts on nearby surface waters, including wetlands, streams, and springs. If Magellan wishes to increase is water appropriation in the future, they would be required to apply for another water appropriation permit from the MDNR. The MDNR would, at that time, make an assessment of the proposed water appropriation on nearby surface and groundwater impacts before granting the water appropriation permit. Magellan will take measures to protect water quality during the release of hydrostatic testing water, see response to comment 1-9 for details. Comment 1-9: Commenter stated the following additional concerns regarding hydrostatic testing, “The water that will be used to test this tank should be hauled off site. Our farm is certified organic and our organic dairy farmer does not want this water to cross his hayfield because of the possible pollution. This would include the metal filings, welding/sandblasting residue, bacterial that resides in the steel and will gest washed out. This must be tested and communicated to those that will be impacted. This should not be released across our renters hay field.” Response: To protect water quality, the National Pollutant Discharge Elimination System/State Disposal System Permit MN0059820 (NPDES/SDS Permit) will require Magellan to meet the following conditions specific to hydrostatic test discharges:

· The Permittee shall employ Best Management Practices to minimize sediment withdrawal and transport. However, in no case, shall sediment levels in the discharge cause or contribute to violation of a water quality standard.

· Energy dissipation devices shall be used to disperse the discharge to as to prevent and/or reduce erosion, bottom scouring and sediment transport.

· All tanks and piping to be tested shall be free from contaminants such as excess product, wax, debris, and liquids. All product shall be removed from the tank or pipe and cleaned prior to hydrotesting.

· This permit does not authorize the discharge of any wastes generated through the cleaning, mechanical scouring or pigging process unless adequately treated (through sedimentation or filtration) to meet discharge effluent requirements through outfall WS 002.

· The discharge of hydrostatic test waters to which treatment chemicals, corrosion inhibitors or biocides have been added is prohibited unless the Permittee has received prior approval from the MPCA. On a case-by-case basis, approval may be given if it has been demonstrated that such treatment is necessary and that the use as prescribed will not result in environmental harm.”

Magellan will discharge the water through a geotextile lined straw bale structure as a best management practice to conform with the conditions of the NPDES/SDS Permit. In addition to the requirements


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identified above, Magellan must collect and analyze samples of the hydrostatic test water for the following parameters:

· Benzene · Total organic carbon · Oil and grease · pH · Total suspended solids · Xylenes

Magellan must submit effluent discharge reports to the MPCA. These reports are available by request from the MPCA. Comment 1-10: Commenter stated the following, “Contrary to your findings this area is a Karst area and should be treated as such. You may say where the tanks are is not a Karst area but that is only because over the years it has been filled in. The karst is immediately adjacent to this whole site should be considered Karst.” Response: The MPCA agrees that the Project is located in an area of Minnesota known for its karst landscape. The EAW correctly identified the nearest surface karst features to the Project as well as the sub-surface geology at and surrounding the Project site (Item 10.a.). Comment 1-11: Commenter requested the following requirements, “Test wells within the 1 mile radius of the project annually and share those results with the private well owners annually. Develop a pollution prevention plan for possible contamination and share that plan with the community and neighbors.” Response: The EAW contains sufficient information regarding the Project’s impact on aquifers and groundwater quality. With respect to pollution prevention planning for possible well contamination, the EAW documents multiple measures (including the Spill Prevention Control and Countermeasure Plan and the Facility Response Plan that Magellan will be required to implement to minimize or mitigate the effects to water resources (see EAW item 11.b.). Comment 1-12: Commenter stated the following, “I request that Magellan notify Eyota Township, Eyota and the neighboring residences of any negative activity that may occur and any results that may be impacting a neighboring well.” Response: This request to report “any negative activity” is unclear and outside the scope of the EAW. However, the MDNR does have a process to evaluate and respond to well interference complaints. As the MDNR indicated in its Preliminary Well Construction Assessment for the Project (see Appendix B of EAW), if the use of the proposed well deprives nearby homes of their domestic water supply as a result of a valid well interference compliant that is affirmed by the MDNR, the use of the well must stop until Magellan establishes a new water supply for the affected homes. Comment 1-13: Commenter stated the following, “I request that air monitoring is done periodically to verify that their control methods they are using are actually working and this should be shared with the neighbors and community.”


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Response: The EAW contains sufficient information regarding the Project’s impact on air quality. Magellan has applied for a state Option 1 Capped Air Emission Permit for the Project. Capped Permits require facilities to monitor daily production, usage records, and monthly calculations of actual emissions. The permit application also required Magellan to conduct air dispersion modeling for the Project (described on pages 29-31 of EAW). The modeling took into consideration representative background air quality conditions in the Project area. Under the Capped Permit, Magellan will be required to develop a written compliance plan including a list of actions, including monitoring, record keeping, and reporting requirements on a daily, monthly and yearly basis. This plan must be completed within 60 days of receiving the Capped Permit and a copy must remain on site at all times. The MPCA Commissioner may request a copy of the current compliance plan if necessary. Capped Permit holders must also submit an annual emission inventory report to the MPCA. Comment 1-14: Commenter requested the following, “Upgrades to the property that were promised the original land owner and never happened. This tank farm has been at that site for over 50 years and the original seller was promised that trees would be planted around the site so that it would not have such a negative view. The only trees at the site after 50 plus years are a few pines that stand about 3 feet tall. I request that Magellan plant trees on the North, West and South sides to show they have concern for what was promised by Williams and what would improve the landscape in this area.” Response: This comment regarding past promises made by a previous owner of the Facility is outside the scope of the EAW. However, as indicated in item 13.d. of the EAW, Magellan has indicated that it plans to plant 16 apples trees on the southern border of the Facility property. Comment 1-15: Commenter stated the following, “This is a highly volatile site with all the flammables. This industry should be held to the same standards of security as any other utility. I request they have a security plan implemented at this site that will protect the community from any possible terrorist activity. This plan should be put into action immediately.” Response: This comment regarding Facility security plans is outside the scope of the EAW. Comment 1-16: Commenter stated that, “Because of unassessed significant environmental concerns, I request that you conduct an Environmental Impact Study.” Response: Comment noted. 2. Comments by Ms. Rebecca Horton, Minnesota Department of Natural Resources. Email received February 5, 2019 Comment 2-1: The commenter stated the following, “The Magellan Terminal is built on karst. Provided the nature of the project, and the karst environment, the DNR has concerns that new sinkholes could form, and that groundwater contamination could occur as a result of the project. DNR groundwater specialists reviewed the project location and EAW, and provided comments in the attachment (enclosed). The DNR recommends that these comments be considered to ensure that the project is


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developed in an appropriate manner so as to not cause pathways for contaminants to reach the groundwater.” Response: Regarding the comment about the Facility being built on karst, please see the response to comment 1-10. This Project will result in an increase of impervious surface at the Project site from 7.9 to 9.6 acres (i.e., increase of 1.7 acres). This increase will be due to construction of the secondary containment area for the new gasoline AST. This change will result in a relatively small increase in industrial stormwater generated by the Project. The secondary containment area of the proposed AST and the existing stormwater collection and infiltration basin have adequate capacity to manage the increase in stormwater. The additional stormwater will be directed to the Facility’s existing stormwater collection and infiltration basin. Some of this additional stormwater would infiltrate into the soil under the existing stormwater basin and some will overflow into the wetland on the northeast side of the Facility site. In addition, some of the stormwater directed to the wetland would infiltrate and some would flow off site to the east to the intermittent steam tributaries to the South Fork Whitewater River. Some of the water flowing in the intermittent streams would also infiltrate into the ground. Therefore, stormwater infiltration will be dispersed and not occur in just one area. This stormwater management approach will help to minimize the formation of new sinkholes. Further, as indicated in item 10.a. of the EAW, according to the Geologic Atlas of Olmsted County (Plate 3), surficial geology at the Project site consists of till, described as an “unsorted, unstratified drift deposited by a glacier; a mix of sand, silt, and clay (typically loam to clay loam).” Depth to bedrock at the Facility is less than 50 feet, as mapped in Plate 2 of the Geologic Atlas of Olmsted County. Stratigraphy reports from the Minnesota Well Index indicate till, consisting primarily of clay, overlies the bedrock. The commercial water well at the Facility (Unique ID 227374) extends 288 feet in depth and terminates in the St. Peter Sandstone Aquifer. The stratigraphy log from this well indicates bedrock lies 22 feet below the ground surface. The uppermost bedrock at the Facility is the Prosser Formation, a thin-bedded limestone and dolomite layer that is part of the Galena Group, or Upper Carbonate Aquifer. The Prosser Formation and underlying Cummingsville Formation, a fine-grained limestone with calcareous shale, comprise the Upper Carbonate Aquifer and total approximately 130 feet in thickness. The Decorah, Platteville, and Glenwood Formations, a group of limestones and shales, underlie the Upper Carbonate Aquifer for approximately 70 feet, followed by 100 feet of the St. Peter Sandstone. No surface karst features (sinkholes or springs) have been identified at the Project site (EAW Figures 8 and 10). The nearest surface karst feature is a sinkhole located 0.96 miles southwest of the Project site (EAW Figure 8). Low permeability clay and silt soils are present above the bedrock layer. This surficial till layer results in a lower sensitivity to pollution transport than other locations in Olmsted County, with estimated contamination travel times in the range of several years to a decade6.


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The Project site has been used as a petroleum products terminal since 1966 and no known surface karst features (e.g., sinkholes) have formed at the Project site during that time. The MPCA has determined that the proposed Project is not expected to result in the increased formation of sinkholes that could lead to groundwater contamination due to the following reasons:

· The nearest known sinkhole to the Project site is approximately 1 mile away. · There is no history of sinkhole formation at the Project site over a period of over 50 years of

Facility operation. · The amount of additional stormwater to be generated by the Project will be relatively small. · The small amount of additional stormwater that will be generated by the Project will be

dispersed over several locations for infiltration. · The proposed gasoline AST will include secondary containment to capture any release that

would occur, so that it would not be able to infiltrate into any sub-surface karst features. · The carbonate bedrock beneath the surficial till layer and the layer of low permeability soils

above the bedrock layer in the Project area will slow stormwater infiltration. Comment 2-2: The commenter stated the following, “With concern for water contamination in mind, the EAW states that industrial stormwater is inspected for the presence of visible sheen prior to discharge. Please describe how the site is configured so the industrial stormwater from the facility’s tank’s secondary containment area can be isolated to prevent water with a visible sheen going directly to the stormwater infiltration basin? What unique design allows the facility to control when water is routed through the Facilities oil/water separator before being discharged to the ground? Is there a redundant BMP control a bypass valve that will be installed with the new underground piping?” Response: Magellan manages the release of the water collected in the secondary containment area in the following ways:

· The containment basin berms must be free of residual oil or other contaminants. · The bypass valve normally must be sealed closed, except during periods of supervised discharge. · If the accumulated water contains no visible oil sheen or film, Magellan opens the bypass valve

to release the water, and reseals the valve once drained. · If the accumulated water has a visible oil sheen of film, Magellan routes the water via a direct

pipeline to an oil/water separator, and reseals the valve once drained. While Magellan’s NPDES/SDS Permit allows for the discharge of the separated water, Magellan chooses to have this water disposed of with a licensed facility, as described in item 11.b.i of the EAW.

Comment 2-3: The commenter stated the following, “Pages 16 - 17: noted “Industrial stormwater generated from other areas of the Facility, such as roads, typically infiltrates into the ground. There is potential that, during particularly wet periods, stormwater discharged from the Facility may follow natural drainage courses through one of the identified PEMC wetlands and then through surrounding farm lands and along highway and railroad ditches to either an intermittent stream tributary to Bear Creek or intermittent streams tributary to South Fork Whitewater River”. The DNR recommends that additional/redundant BMPs be installed to prevent stormwater from leaving the facility and entering nearby waters.”


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Response: Comment noted and although the MPCA believes that the proposed industrial stormwater best management practices (BMPs) (e.g., using the new AST’s secondary containment area, and existing stormwater collection and infiltration basin) are adequate, we will pass your recommendation on to Magellan. Comment 2-4: The commenter stated the following, “Magellan has applied for two DNR General Permits for Temporary Appropriation. These DNR Water Appropriation Permits are required for construction dewatering that exceeds 10,000 gallons per day, or one million gallons per year, that is associated with the construction of the new AST, grading, installation of utilities, storm water facilities, vapor recovery unit, MMC, or road improvements.” Response: Comment noted. Table 8-1 of the EAW reflects the MDNR water appropriations permits needed for the Project. Comment 2-5: The commenter stated the following, “The use of more than 10,000 gallons of water per day, or one million gallons per year, for the hydrostatic testing of tanks or pipelines must be approved under a DNR Water Appropriation Permit. DNR General Permits for Temporary Appropriation are issued for periods of time that do not exceed one year in length.” Response: Comment noted. Comment 2-6: The commenter stated the following, “Magellan has also received a medium risk letter for the Well Construction – Preliminary Assessment File 2018-3446 for the new well.” Response: Comment noted. This letter was included in the EAW as Appendix B. Comment 2-7: The commenter stated the following, “Geologic mapping and characterization, groundwater level response, dye tracing in the project vicinity, geophysical investigation results, and site-specific boring logs collected at the nearby site of a proposed ethanol plant illustrate that the Magellan Terminal is built on karst. EAW Figure 10 shows that the terminal location is on karsted bedrock. The first bedrock unit in the vicinity is the Prosser Formation of the Galena Group. The Galena Group is well characterized as karst in Minnesota (Alexander and Lively, 1995; Alexander et al., 1996; Green et al., 1997, 2002; Runkel et al., 2003, 2014). Dendritic drainage patterns, shallow depth to soluble bedrock, and nearby sinkhole clusters and springs highlight the terminal vicinity as karst. Sinkholes have been mapped in the Prosser Formation within 1-mile of the proposed above ground storage tank. The majority of wells in the immediate vicinity of the terminal show depth to bedrock in the thirty feet or less range. Two wells on-site, 558143 and 227374, log the depth to bedrock at 14 feet and 22 feet respectively. The 19 to 35 feet range of depth to bedrock reported from the tank site soil borings suggest a highly weathered karst bedrock surface. Material descriptions of the Prosser from boring logs collected at the site of a proposed ethanol plant roughly 3,500 feet south of the terminal by American Engineering Testing noted depth to the Prosser in the 10-20 foot range with fracturing described as very fractured to moderately fractured (AET, 2008).


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Field-verified karst features, such as sinkholes, are direct evidence that karst processes are active both on the surface and in a karst aquifer in the subsurface. However, although there are no sinkholes on the land surface at the terminal location, this does not imply the absence of karst processes at land surface or karst hydrology in the subsurface. At a Prosser Formation quarry located roughly 1.6 miles west of the project area, vertical staining within exposed quarry walls illustrates surface water-groundwater pathways common in the Prosser Formation karst (Figure 1). Surface karst features are likely not expressed at the terminal because the Browerville till at the project site is slightly thicker than the other surrounding surficial materials and more effectively masks the subsurface karst. Karst is well known for heterogeneity in geologic and hydrologic conditions over short distances. Therefore, thorough and detailed geologic investigations in karst should go beyond standard site characterization using soil borings and use geophysical techniques (Tennessee Department of Environment and Conservation, 2014).” Response: Please see the response to comment 1-10. In addition, item 10 of the EAW contains much of the information presented in this comment. The EAW and a geotechnical study conducted by Kleinfelder in October 2017 (Geotechnical Report, attached as Appendix C) contains sufficient information regarding the geology in and around the Project area. Comment 2-8: The commenter stated the following karst concerns regarding the Project, “Magellan is proposing to expand the existing facility by constructing a field-erected, 5-million-gallon above-ground storage tank for additional gasoline storage and offloading capacity. Construction includes containment berms around the tank and underground containment drainage to a stormwater basin. Infiltration of stormwater in karst settings requires special considerations (MPCA, 2018).

Infiltrating large quantities of water in this geologic setting may increase the probability of sinkhole formation. Additionally, pollutants being carried by stormwater runoff in this setting may pass rapidly through the subsurface into groundwater. Increased impervious area within the facility footprint will increase volumes routed to the stormwater basin, increasing the potential for sinkhole development and rapid movement of contaminated stormwater into the Galena aquifer below. The Galena aquifer in the project vicinity responds very rapidly to recharge events, highlighting its connectivity to the land surface (Figure 2).

In addition, once filled with gasoline, the new storage tank will be quite heavy which requires assurances that the bedrock and construction fill materials be stable and not subject to subsidence. Due to the underlying karst, the geology underlying the containment structure should be thoroughly characterized to ensure that no voids or preferential pathways exist in the proposed location.” Response: As indicated in response to comment 2-1, the quantity of new stormwater generated by the Project will be relatively small. In addition, as indicated in response to comment 2-1, stormwater infiltration will be dispersed over several areas. Stormwater infiltration from the Project is not expected to result in a significant effect on sinkhole formation. With respect to concerns about pollutants being carried by stormwater runoff, the Facility will be required to inspect industrial stormwater collected in its AST’s secondary containment structure for presence of a visible sheet prior to discharge. If a sheen is observed, as required by the Facility’s


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NPDES/SDS Permit, the stormwater will be treated by the Facility’s oil/water separator. Also, please see response to comment 2-2. The Geotechnical Report (Appendix C) corroborated geologic data obtained from the Geologic Atlas of Olmsted County. The Geotechnical Report concluded that no subsurface conditions were encountered with a potential for collapse or subsidence due to voids or solution cavities, and found sand and clay glacial soils underlain by limestone bedrock, with depths to bedrock observed in the soil borings from 19 to 35 feet. Magellan does not plan to construct tanks or other components of the Project directly on or in contact with bedrock. Should voids or cavities be found, Magellan’s geotechnical consultant indicated that standard construction practices in the karst region will be followed, such as removing the bedrock around the void and filling the void with rock and concrete such that a solid base is formed and the void eliminated.

Comment 2-9: The commenter recommended that the EAW contain the following additional information:

a. The seven borings used to characterize the Magellan Terminal site are insufficient to fully characterize the karst setting. However, the soil boring may be valuable in designing and interpreting future on-site investigations. The soil borings should be labeled in EAW Figure 7 and the soil borings logs should be provided in EAW Appendix A.

b. The soil borings should be supplemented with surface geophysical characterization of

the site using electrical resistivity transects, gravity, and/or other surface geophysical methods to adequately characterize karst conditions at the terminal site. Bedrock anomalies detected by the surface geophysics may require exploratory soil borings to characterize and interpret them.

c. Additional details regarding the relationship of the grading, excavation and filling with

gravel and clay to the karst bedrock below is needed. This should be shown on grading plan sheets and cross sections. The above-ground tank’s foundation design, testing and workflow should be described in more detail.

d. The Minnesota Springs Inventory shows spring and seep locations near the project

location. Content related to springs and seeps should be added to the answer to EAW Question 11. The location of springs should be added to EAW Figure 10.

Response: The MPCA does not believe additional study, such as electrical resistivity transects, gravity and/or other surface geophysical methods, or additional details of Project construction are required to determine if there is the potential for significant environmental effects. The EAW and the Geotechnical Report (Appendix C) contains sufficient information regarding the geology in and around the Project area and the potential for sinkhole formation. The Geotechnical Report found no subsurface conditions with a potential for collapse or subsidence due to voids or solution cavities.


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In preparing the EAW figures, Magellan used the MDNR’s Karst Feature Inventory Points data and did not use the MDNR’s Springs in Minnesota data. However, the MPCA compared the two data sets and found that the Karst Features Inventory Points contained all of the features identified in the Minnesota Springs Inventory dataset for the areas shown in the EAW figures. 3. Comments by Ms. Heather Lukes, Minnesota Department of Transportation. Letter received

February 6, 2019. Comment 3-1: MnDOT finds that the EAW is accurate but incomplete. There are potential state transportation system impacts that warrant further investigation before the project is commenced. These impacts are related to additional runoff onto MnDOT's right of way. Please have the applicant submit a table of peak runoff rates pertaining to MnDOT Right of Way existing and proposed conditions for the 2, 10, and 100 year Atlas 14, 24-hour storm events. Response: The design of the tank containment berm includes vegetation on the outer slopes to eliminate new impervious surface beyond the tank containment basin. The remaining construction will occur in areas that are currently impervious and will be impervious upon completion of the Project. The water quality volume associated with the new impervious surface of the tank containment basin will be discharged through a manually operated valve to control the flow rate to prevent erosion and discharge of sediment to the existing stormwater collection and infiltration basin. If the stormwater collection and infiltration basin overflows, stormwater flows to an onsite wetland before discharging off site. Therefore, the MPCA does not anticipate a significant increase in peak runoff rates as a result of the construction of the tank. Comment 3-2: There is a typo on page 33 of the EAW. On page 33 the sentence states "According to the Minnesota Department of Transportation (Mn DOT) average AADT is 3,150 vehicles on Highway 42 and 5,300 vehicles at US Highway 42." It should read 5,300 vehicles at US Highway 14. Response: Comment noted and correction made in attached errata sheet (Appendix D).

APPENDIX D


Magellan Rochester Terminal Expansion Project Environmental Assessment Worksheet (EAW)

ERRATA SHEET

Item 16. - Page 28: In the paragraph regarding PSD, the EAW incorrectly stated that, “… the Facility-wide PTE is and will remain less than 250 tons per year…”. Delete “250 tons per year” and replace it with “100 tons per year”. Item 18.b. – Page 33: There is a typo on page 33 of the EAW. On page 33 the sentence states "According to the Minnesota Department of Transportation (Mn DOT) average AADT is 3,150 vehicles on Highway 42 and 5,300 vehicles at US Highway 42." It should read 5,300 vehicles at US Highway 14.

Documents

Magellan Rochester Terminal Expansion Project Findings of ... · p-ear2-155b. Printed on recycled paper containing at least 30% fibers from paper recycled by consumers. STATE OF MINNESOTA