ENVIRONMENTAL ASSESSMENT WORKSHEET

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2 ENVIRONMENTAL ASSESSMENT WORKSHEET Note to reviewers: The (EAW) provides information about a project that may have the potential for significant environmental effects. This EAW was prepared by the Minnesota Pollution Control Agency (MPCA), acting as the Responsible Governmental Unit (RGU), to determine whether an Environmental Impact Statement (EIS) should be prepared. The project proposer supplied reasonably accessible data for, but did not complete the final worksheet. Comments on the EAW must be submitted to the MPCA during the 30-day comment period, which begins with notice of the availability of the EAW in the Minnesota Environmental Quality Board (EQB) Monitor. Comments on the EAW should address the accuracy and completeness of information, potential impacts that are reasonably expected to occur that warrant further investigation, and the need for an EIS. A copy of the EAW may be obtained from the MPCA by calling An electronic version of the completed EAW is available at the MPCA Web site 1. Project Title:, Combined Wastewater Treatment System Expansion 2. Proposer: Rahr Malting Company, Inc. and Koda Energy, LLC 3. RGU: Minnesota Pollution Control Agency Contact Person Paul Kramer Contact Person Denise M. Leezer and Title President and Title Project Manager Address 800 West First Avenue Address 520 Lafayette Road North St. Paul, Minnesota Phone Phone Fax Fax Reason for EAW Preparation: EIS Scoping Mandatory EAW X Citizen Petition RGU Discretion Proposer Volunteered If EAW or EIS is mandatory give EQB rule category subpart number and name: Minn. R , subp.18 C and subp Project Location: County Scott City/Twp Shakopee SE 1/4 SW 1/4 Section 1 Township T115N Range R23W NE 1/4 p-ear1-04 TDD (for hearing and speech impaired only): Printed on recycled paper containing 30% fibers from paper recycled by consumers

3 Tables, Figures, and Appendices attached to the EAW: Exhibit 1 County map showing the general location of the project Exhibit 2 U.S. Geological Survey 7.5 minute, 1:24,000 scale map indicating project Exhibit 3 Aerial Photo showing all significant site features and the proposed project Exhibit 4 Site layout with the wastewater treatment system and Koda Energy identified Exhibit 5 Minnesota Department of Natural Resources (DNR) Natural Heritage and Nongame Research letter Exhibit 6 State Historic Preservation Office (SHPO) Cultural Resources letter Exhibit 7 Proposed wastewater treatment system Process Flow Diagram Exhibit 8 Proposed heat and power plant Process Flow Diagram Exhibit 9 Sensitive Receptor Map 6. Description: a. Provide a project summary of 50 words or less to be published in the EQB Monitor. Rahr Malting Company (Rahr Malting) and Koda Energy, LLC (Koda Energy) are proposing to expand the existing wastewater treatment system at Rahr Malting and construct a new heat and power plant adjacent to the existing Rahr Malting facility. The existing wastewater treatment system was designed to treat an average flow of 1.5 million gallons per day (MGD). The proposed expansion will increase the annual average discharge to MGD, and the average wet weather (AWW)/peak daily/peak hourly wet weather (PHWW) flow rates will increase to 2.41 MGD. The treated wastewater is discharged to the Minnesota River. Non-contact cooling water is discharged via the same outfall to the Minnesota River. Koda Energy is a limited liability corporation whose members include Rahr Malting and the Shakopee Mdewakanton Sioux Community. Koda Energy will use byproducts from Rahr Malting for up to 30 percent of its biomass fuel requirements to produce, on average, up to 17.8 Megawatts (MW) of electrical energy and 120,000 pounds/hour (lbs/hr) of steam. This combination of steam and electricity represents the total energy output. For example, the facility could produce more than 120,000 lbs/hr of steam, but then would concurrently produce less than 17.8 MW of electricity. Rahr Malting will purchase the steam for process heat. Koda Energy will either sell the electricity to Rahr Malting and/or will wholesale the power to an electric utility. b. Give a complete description of the proposed project and related new construction. Attach additional sheets as necessary. Emphasize construction, operation methods and features that will cause physical manipulation of the environment or will produce wastes. Include modifications to existing equipment or industrial processes and significant demolition, removal or remodeling of existing structures. Indicate the timing and duration of construction activities. Overview Rahr Malting is a manufacturer of barley malt. The barley malt product is sold to various beverage and malting food industries. Rahr Malting is a privately held company and the third largest commercial malting company in the United States. Rahr Malting is located on an 18-acre parcel in Shakopee, Scott County. The site is located on the northwest side of Shakopee, adjacent to and south of U.S. Highway

4 The Rahr Malting wastewater treatment system currently has a National Pollutant Discharge Elimination System (NPDES)/State Disposal System (SDS) Permit for the discharge of non-contact cooling water and wastewater. Rahr Malting treats 66 percent to 75 percent of its process wastewater in the existing wastewater treatment system and discharges to the Minnesota River under the conditions included in the permit. Non-contact cooling water is discharged via the same outfall to the Minnesota River. The remaining 25 percent to 33 percent of Rahr Malting s process wastewater is discharged to the city of Shakopee wastewater collection system for treatment at the Metropolitan Council Environmental Services Blue Lake Wastewater Treatment Facility (MCES Blue Lake Facility). As of January 1, 2008, the MCES Blue Lake Facility will no longer accept process wastewater from Rahr Malting. Because the MCES Blue Lake Facility will no longer be available to accept the process wastewater, Rahr Malting is proposing to expand its existing wastewater treatment system to treat all process wastewater on site. The MCES Blue Lake Facility will continue to treat sanitary wastewater from Rahr Malting and Koda Energy after completion of the proposed wastewater system expansion. Rahr Malting currently purchases electricity from Xcel Energy. Koda Energy is proposing to build a combined heat and power biomass plant that will provide, on average, 120,000 lbs/hour of steam to Rahr Malting and 17.8 MW of electricity that may either be sold to Rahr Malting or will be sold wholesale to an electric utility. A natural gas pipeline, owned by Rahr Malting delivers natural gas to the facility. Koda Energy is a limited liability corporation whose owners include Rahr Malting and the Shakopee Mdewakanton Sioux Community, a federally recognized Indian Tribe. Koda Energy will purchase dry biomass malt byproducts from Rahr Malting to meet a portion of Koda Energy s biomass fuel requirements. The fuel handling system is designed for a fuel mix of 35 percent oat hulls, 35 percent wood shavings and 30 percent byproducts from Rahr Malting. Koda Energy will obtain well water (up to 146,000 gallons per day) from wells owned by Rahr Malting under an existing DNR water appropriation permit. Koda Energy will discharge up to 72,000 gallons per day of boiler blowdown, cooling tower blowdown, and reverse osmosis reject water to the Rahr Malting wastewater treatment system. The proposed wastewater treatment system expansion and the proposed heat and power plant will be built next to each other on property owned by Rahr Malting and will impact the same geographic area. A covered conveyor will transfer malt byproducts from Rahr Malting to the truck loading station at Koda Energy. A pipe from wells owned by Rahr Malting will deliver well water to Koda Energy. A discharge pipe from Koda Energy will deliver boiler blowdown, cooling tower blowdown, and reverse osmosis reject water to the Rahr Malting wastewater treatment system. Trucks delivering fuels to the Koda Energy truck unloading station will enter and exit on haul roads owned and maintained by Rahr Malting. Phased and Connected Two projects are considered phased actions if they are to be undertaken by the same proposer, will have environmental effects on the same geographic area, and are substantially certain to be undertaken sequentially over a limited period of time. Minn. R , subp. 60 (2005) According to the Environmental Quality Board (EQB), A Citizen s Guide: An Introduction to Environmental Review, only one and not all of a group of owners need to be involved in both projects as long as that owner s stake is substantial in order for two projects to be considered phased actions 3

5 under environmental review rules. The MPCA staff, working with the EQB staff, has determined that an ownership stake of 49 percent is considered a substantial ownership. Based on the EQB s Guidance, the MPCA concluded that there is sufficient common ownership in this case to qualify as a phased action. The MPCA staff also concluded that the proposed Rahr Malting and Koda Energy project would have environmental effects on the same geographic area. The fact that the environmental effects from the two projects may be of different types does not preclude the projects from qualifying as phased actions. The applicable rule, Minn. R , subp. 60, does not require that the environmental effects from two projects be of the same type in order for the projects to be phased actions. The rule simply requires that two projects have environmental effects on the same geographic area. Finally, permit applications have been submitted for both projects and the two projects are occurring simultaneously. Thus, the MPCA staff concluded that the two projects are substantially certain to be undertaken sequentially over a limited period of time. Two projects are "connected actions" if a responsible governmental unit determines one project would directly induce the other; one project is a prerequisite for the other and the prerequisite project is not justified by itself; or neither project is justified by itself. Minn. R , subp. 9b (2005) The boiler blowdown, cooling tower blowdown, and reverse osmosis reject water from Koda Energy will be discharged at a rate of 50 gallons per minute (gpm) - 72,000 gallons per day - to the Rahr Malting wastewater treatment system (with an existing annual average flow of 1.43 MGD and a permit limit of 1.5 MGD daily average). Although Koda Energy has asserted that it would simply find another means of disposing of its boiler blowdown, cooling tower blowdown, and reverse osmosis reject water, the MPCA staff must base its determination on the projects as they are proposed. Rahr Malting needs to amend the current NPDES/SDS Permit for the wastewater treatment system to accommodate the additional flow from Koda Energy. Although it is not the sole criteria for the proposed expansion at Rahr Malting, the wastewater treatment system expansion must consider the discharge of wastewater from Koda Energy in its design. As proposed, the proposed heat and power plant is dependent on the proposed wastewater treatment system expansion to dispose of Koda Energy s wastewater. The projects are, therefore, connected actions under Minnesota s environmental review rules. Malting Process/Existing Wastewater Treatment System The malting process involves receiving, cleaning, grading, and storage of barley. The facility includes five (5) malt houses for germination, seven (7) kilns for drying, storage, cleaning, and loading for shipment of malted barley. Current facility annual production is approximately 22,000,000 bushels of barley received, 24,000,000 bushels of malted barley shipped, and 50,000 tons of related by-products shipped. Malting barley or other grain involves sprouting the grain by either spraying with water or steeping in water under controlled conditions. After the grain is appropriately sprouted, the grain is dried in a kiln; which stops the grain from sprouting further and achieves the desired color and flavor. The malting process requires large quantities of water for spraying and steeping, large amounts of process heat for drying the grain, and large amounts of electricity for operating grain handling and other process equipment. 4

6 Table 1: Steeping Discharge (1,000 gallons/batch) House No. 1 No. 2 No. 3 No. 4 No. 5 Overflow First Drain Spray Second Drain Third Drain Fourth Drain Fifth Drain Total In 1997, an NPDES/SDS Permit authorized Rahr Malting to construct a wastewater treatment system to treat process wastewater from the company s barley malting operation. The wastewater treatment train includes fine screens, an equalization tank, a sequencing batch reactor (SBR), a solids holding tank, an effluent equalization tank, effluent filter, and re-aeration basin. Sanitary wastewater from Rahr Malting discharges to the municipal sanitary sewer and does not mix with the process wastewater. Previously, waste activated sludge was discharged to the MCES Blue Lake Facility, but is currently dewatered and subsequently land applied. The system is currently treating an average of approximately 1.43 MGD with an influent Five-Day Carbonaceous Biochemical Oxygen Demand (CBOD 5 ) strength of 630 milligrams per liter (mg/l). The limit of 68 kilograms per day (kg/day) average of CBOD 5 (150 lbs) in the existing permit represents the amount gained from a 1997 trading agreement between the MPCA and Rahr Malting. The proposed increase of CBOD 5 to 96.5-kg/day average represents nonpoint source (NPS) load reduction units that Rahr Malting obtained during the term of the existing permit. Rahr Malting operates and maintains four (4) deep wells and one well of 180-foot depth on site. The combined permit capacity for water withdrawal for these wells is 1.14 billion gallons per year. These wells provide all necessary process water. Municipal water is also available and services the domestic needs of various office complexes, etc. Wastewater Treatment System Expansion (Proposed Project) Proposed Wastewater Treatment System Expansion Rahr Malting is proposing to expand the wastewater treatment system. The proposed expansion will include the installation of a membrane bioreactor (MBR) to run in parallel with the existing SBR system. The annual average wet weather design flow will increase from 1.5 MGD to MGD with an AWW/PHWW rate of 2.41 MGD. The MPCA staff concluded that the freeze on TSS will serve as a freeze on mercury, since mercury primarily associates with solids in effluents; therefore, a nondegredation review for mercury is not required. The proposed MBR system is being designed to treat an average daily flow of 1.5 MGD and a peak instantaneous flow of 2.25 MGD. The flow rates for the proposed wastewater treatment system expansion were determined from review of the malting process, available flow equalization, and planned flows from the proposed heat and power plant. The proposed wastewater treatment system expansion will be located adjacent to the existing wastewater treatment system on undeveloped land. 5

7 The proposed wastewater treatment system expansion consists of a biological treatment system (activated sludge process) in addition to the MBR filtration system. Activated Sludge Process The activated sludge process is an aerobic, biological process that uses the metabolic reactions of microorganisms to remove substances exerting an oxygen demand. By definition, activated sludge is the suspension of concentrated micro-organisms in wastewater. Wastewater enters a reactor basin where micro-organisms are brought into contact with organics in the influent. The organic matter serves as a carbon and energy source for microbial growth and is converted into microbial cell tissue and oxidized end product (like carbon dioxide and water). Contents of the reactor basin are referred to as mixed liquor suspended solids (MLSS). When the MLSS is discharged from the reactor basin, a means to separate the micro-organisms from the treated wastewater is provided. Usually gravity settling is used. Filtration, as proposed in the MBR, can also be used. The concentrated microbial solids are then recycled back to the reactor basin to maintain the concentrated microbial population for degradation of the incoming organic materials. Because the micro-organisms are continually synthesized in this process, a means must be provided for wasting some of the generated microbial solids. This wasting can occur either from settling basin(s) and/or the activated sludge reactor basin itself. The process wastewater from Rahr Malting will be pumped from the existing screening process wet well and will be split between the two activated sludge systems (MBR and SBR). The new MBR treatment system will consist of three concrete reactor tanks and three membrane tanks. Each reactor tank has interior dimensions of 44 feet by 67.5 feet by 23 feet. Three positive displacement blowers, with a capacity to supply 3,060 standard cubic feet per minute (SCFM) at 11-pound force per square inch gauge (psig), will provide aeration to the tanks. Two blowers will operate and one will be on standby. Each tank will contain fine bubble diffusers for the transfer of oxygen to the wastewater. The MLSS will flow by gravity to the membrane tanks. Membrane Filtration Membranes are materials that can separate particles and molecules from liquids. The membranes are hollow strands of porous polymer fibers that prevent the passage of certain contaminants while allowing water molecules to flow to the inside of each strand. This selective filtration is possible because the surface of each membrane fiber consists of billions of microscopic pores that block the passage of all particles larger than the size of the pores, creating a physical barrier to contaminants. Water is drawn through the pores with the use of a slight suction, much like that required when sipping liquid through a straw. The proposed membrane system is composed of hollow-fiber membrane modules submerged on racks in three concrete tanks. Each membrane tank has inner dimensions of 14 feet in length by 13 feet in width by 8 feet, 3 inches in height. The membrane system contains 160 membrane modules; the modules are housed on 10 racks (16 modules per rack). Water is drawn through the membranes by a suction developing filtrate pump. There are three filtrate suction pumps each with a capacity to pump gpm at 25 feet total dynamic head. Particles greater than 0.1 microns (µm) are filtered out of the water. Mixed liquor is returned back to the activated 6

8 sludge tanks continuously using three pumps through a common manifold. Changes in effluent flow rates are provided using a variable frequency drive on the filtrate pumps and mixed liquor return pumps. Discharge The treated water from the MBR process will mix with the treated water from the SBR process prior to sampling. Some of the water is used for non-contact cooling before discharge to the common discharge outlet. The Rahr Malting wastewater treatment system will continue to discharge to the Minnesota River at river mile 25.3 after the proposed expansion. This section of the Minnesota River is considered impaired by Section 303(d) of the federal Clean Water Act. A water body is impaired if it does not meet one or more of the federal Clean Water Act s water quality standards. This reach of the Minnesota River is considered impaired for low dissolved oxygen levels, caused by high phosphorous levels in the river. The primary tool for addressing impaired waters is a pollution reduction plan called a Total Maximum Daily Load, or TMDL. A TMDL is the maximum amount of a pollutant a water body can receive without violating water quality standards. The TMDL process identifies all sources of the pollutant and allocates necessary reductions among the various sources. These reduction strategies form the basis of an implementation plan. In 1985/1987, a low dissolved oxygen TMDL study for the reach of the Minnesota River from Jordan to its confluence with the Mississippi River was developed. The proposed expansion increases the capacity of the existing wastewater treatment system and increases the volume of discharge. No flow limitations will be included in the proposed draft NPDES/SDS Permit. The calendar month average CBOD 5 concentrations will increase from 68 kg/day to 96.5 kg/day. The increase in CBOD 5 load from the wastewater treatment system is offset by the nonpoint sources reduction projects previously achieved by Rahr Malting. The mass ammonia limits will remain the same after the proposed expansion. The TSS mass limitations will remain the same after the proposed expansion. The monthly average phosphorus limit (2 mg/l) will be changed to a more stringent monthly average limit (1 mg/l) and the mass concentrations of phosphorus discharged to the Minnesota River will remain the same. Limits for ph and dissolved oxygen will also remain the same after the proposed expansion. With the NPS load reduction units previously obtained by Rahr Malting, the proposed effluent limits in the current draft NPDES/SDS Permit will not impact the requirements included in the current TMDL. Trading Agreement In 1995, Rahr Malting proposed to build its own wastewater treatment system. The Rahr Malting process water was being discharged to the MCES Blue Lake Facility. Because the reach of the Minnesota River from Jordan to its confluence with the Mississippi River is classified as impaired for low dissolved oxygen levels, any new discharge was required to comply with the requirements of the 1985 (amended 1987) Waste Load Allocation for the lower Minnesota River included in the TMDL. Rahr Malting agreed to install and maintain NPS best management practices (BMPs) and received credit for the pollution reductions. Rahr Malting agreed to come up with 150 NPS load reduction units upstream of its facility (one unit of trading credit was defined as the equivalent of one pound per day of CBOD 5 ). Rahr Malting agreed to spend $250,000 on projects that were approved by MPCA staff. The conditions of the agreement were specified in the NPDES/SDS Permit that was issued on January 8,

9 The 1997 NPDES/SDS Permit limited the phosphorus discharge and required Rahr Malting to reduce CBOD 5 from nonpoint sources of pollution in the upper portions of the Minnesota River within five years. These NPS load reduction units offset the additional loads from the Rahr Malting wastewater treatment system. By the fall of 1999, four NPS sites and five projects with associated BMPs had been found, evaluated, approved, and constructed. The five projects exceeded the required 150 NPS load reduction units and resulted in a total of NPS load reduction units (an additional 62.8 lbs/day). In the proposed draft NPDES/SDS Permit for the proposed wastewater treatment system expansion, Rahr Malting will be given credit for the NPS load reduction units that were achieved as a result of the five projects. The NPS load reduction units will offset the proposed increase in CBOD 5 of 28.5 kg/day for the proposed expansion and will not impact the requirements of the 1985 (amended 1987) Waste Load Allocation for the lower Minnesota River. The proposed draft NPDES/SDS Permit will not authorize Rahr Malting to obtain additional NPS load reduction units above lbs CBOD 5 per day. No additional nonpoint load reduction units will be credited to Rahr Malting should future trades, required for replacement purposes, exceed the current NPS load reduction units. Proposed Combined Heat and Power Plant The proposed heat and power plant will include a fuel receiving building, fuel storage bins, fuel processing (grinders), fuel combustion, air pollution control equipment, and ash handling and disposal. Fuel receiving, handling, storage, and processing will generate truck traffic and airborne particulate matter (PM). Potential emissions of carbon monoxide (CO) and nitrogen oxides (NO X ) from fuel combustion will exceed 250 tons per year, designating the proposed facility a major source under U.S. Environmental Protection Agency (EPA) New Source Review Rules. Koda Energy will emit more than new source review significance levels for particulate matter under 10 microns (PM 10 ). Koda Energy will emit less than new source review significance levels of sulfur dioxide (SO 2 ), volatile organic compounds (VOCs), and hazardous air pollutants (HAPs). The proposed boiler will control NO X by firing finely ground fuel in suspension burners, air-staging with separated over-fire air (SOFA), and a selective non-catalytic reduction system (SNCR). A multicyclone and an electrostatic precipitator (ESP) will control particulate emissions and good combustion practices will control carbon monixide emissions. Ash handling and disposal will generate truck traffic and airborne particulates. Koda Energy will control particulate emissions from fuel delivery, handling and processing by enclosing emissions sources and providing fabric filter dust collection at transfer points. Dustless unloading and fabric filter dust collection will control particulate emissions from ash handling and unloading. Paving and street sweeping will control fugitive dust emissions from truck traffic. The proposed heat and power plant operations will include the following four (4) basic processes: 1. Fuel handling and processing fuel is delivered to Koda Energy, stored in one of ten fuel storage bins, conveyed to a set of four grinders, ground, and delivered to the fuel metering bin, which meters fuel to the boiler; 2. Fuel combustion the boiler burns fuel to produce steam; 8

10 3. Power generation a portion of the steam heats glycol in heat exchangers to provide process heat for Rahr Malting and another portion of the steam powers a condensing steam turbine for electrical power generation; and 4. Ash storage and removal ash from the combustion process is stored and then removed off site for disposal. Fuel Handling and Processing Trucks will deliver 70 percent of the fuels to a receiving building. Trucks will either be walking bottom beds, hopper trucks, or straight trucks. All unloading will occur indoors. Rahr Malting will pneumatically convey the other 30 percent of the fuels (malt byproducts) to the fuel delivery building. A baghouse will control particulate emissions from unloading operations and will maintain negative pressure during unloading to prevent dust from exiting the building. While the fuel delivery station can receive up to four trucks (100 tons) of fuel per hour, the fuel storage feed conveyor (30 tons per hour) and the proposed boiler firing capacity (21 tons per hour) ultimately limit fuel deliveries and processing to an average 8 trucks per day. The facility can store four days worth of fuel in the on-site fuel storage bins and can store up to two hours of fuel in the ground fuel metering bin. The fuel handling system is designed for a fuel mix of 35 percent oat hulls, 35 percent wood shavings, 30 percent byproducts from Rahr Malting natural gas, and liquid propane gas (LPG) will serve as backup fuels. (Additional biomass, such as energy crops, have been proposed to be blended into the proposed fuel mix, at a later time. Additional fuel requirements are discussed in Section 23.) Natural gas is the primary backup fuel fired with LPG used as a standby pilot fuel source. Northern Natural Gas will supply natural gas to Koda Energy through a service line owned and operated by Rahr Malting. Service connections to Minnegasco are also available. An enclosed conveyor system will deliver fuel to the proposed boiler. Fabric filters will control dust at all transfer points. A 30-ton per hour conveyor will deliver the fuel from the truck receiving building to one of ten fuel storage bins. Another set of conveyors will then deliver fuel from the storage bins to a set of four grinders in the grinder building. The grinders will reduce the fuel to a fine powder. A pneumatic system will convey the fuel from the grinders to the day metering bin. The day metering bin will feed the fuel to the boiler at the boiler firing rate. The Boiler (Fuel Combustion/Power Generation) A suspension boiler with a design heat input of million British thermal units per hour (MMBtu/hr) will burn the biomass fuel. The boiler will produce, on average, 120,000 lbs/hour of process steam for Rahr Malting and 17.8 MW of electricity. An outdoor two-cell evaporative cooling tower will provide cooling as required. The boiler is designed to burn up to 42,000 lbs/hour of biofuels. As a back-up fuel, the boiler can also burn up to 240 MMBtu/hr of natural gas. The boiler will control NO X with burner air staging, burner staging, SOFA, and a SNCR. An ESP will control PM. 9

11 Ash Handling and Removal Based on the design fuel mix, at maximum capacity the boiler will generate 8,970 tons per year of ash. The ash is composed of 95 percent fly ash and 5 percent bottom ash. A pneumatic dense phase conveying system will transport 2,100 lbs/hr of ash from the boiler bottom ash hopper, the dust collector (multi-cyclone) ash hoppers, and the ESP ash hoppers to an ash storage bin. A dustless ash unloader will use a fine water mist to condition the ash and prevent particulate emissions. Koda Energy is exploring beneficial uses for the fly ash produced by the biomass boiler. Until a beneficial use is found, one truck per day of ash will be sent to a landfill for disposal. Construction will require the delivery and storage of structural steel and prefabricated large equipment and machinery. Construction will involve the use of heavy equipment to excavate up to 10,000 cubic yards of soil, remove inappropriate fill, and move and erect large machinery and equipment. Construction will also involve welding, grinding, cutting, drilling, hammering, and other activities that generate noise. The Koda Energy construction schedule anticipates 365 days for construction, which will begin as soon as the proper permits are issued. Construction activities will have the potential to increase emissions of fugitive dust, contaminate stormwater runoff with PM, and increase noise. Koda Energy will comply with the Stormwater Pollution Prevention Plan (SWPPP) and will mitigate stormwater runoff. Potential Environmental Issues Potential Air Quality Impacts Koda Energy will emit the following criteria pollutants: NO X, CO, PM, PM 10, VOCs, and SO 2. HAPs, including hydrochloric acid, will also be emitted. Air dispersion modeling assessed the impacts of criteria pollutants upon fish, wildlife, and ecologically sensitive resources. (Criteria pollutant impacts on fish, wildlife and sensitive resources are discussed in Section 11. Air impacts are discussed in Section 23.) The biomass boiler will increase total air emissions on the site. Oxides of nitrogen, PM and CO will exceed significance levels for federal Prevention of Significant Deterioration permitting. Koda Energy proposed Best Available Control Technology (BACT) for these pollutants. The biomass-fired boiler will use SOFA and SNCR to control NO X emissions. A multicyclone and an ESP will control PM emissions. Koda Energy will also emit potential HAPs that may impact nearby fish, wildlife and ecologically sensitive resources. An Air Emissions Risk Analysis (AERA) was prepared to assess the potential human health impacts. A mercury study was prepared as part of the AERA process. (HAP impacts on fish, wildlife and sensitive resources are discussed in Section 11. Air impacts are discussed in Section 23.) Construction will generate traffic. The proposed wastewater treatment system expansion will not significantly increase traffic after construction, but the proposed combined heat and power plant will increase truck traffic by about six trucks per day and will increase employee traffic by up to ten cars per day. No new parking areas will be required. (Section 21 discusses traffic impacts and Section 22 discusses vehicle related emissions.) The proposed wastewater treatment system expansion is an insignificant activity under Minn. R , subp. 3(I). 10

12 Potential Water Quality Impacts Construction may impact surface water runoff. Both components of the project will require an MPCA General Permit for Construction Activity (see Section 16). Project activities upon completion of construction are similar to those already present at Rahr Malting and are compatible with the current SWPPP. (Specific activities to address surface water runoff are discussed in Section 17.) The proposed expansion will discharge to the Minnesota River, an impaired waterway that does not meet current water quality standards. This proposed expansion increases the capacity of the existing wastewater treatment system and increases the volume of discharge. No flow limitations will be included in the proposed draft NPDES/SDS Permit. The daily carbonaceous BOD (biological oxygen demand) concentrations will increase from 68 kg/day to 96.5 kg/day. The increase in CBOD 5 load from the wastewater treatment system will be offset by the NPS reduction projects previously achieved by Rahr Malting. The mass ammonia limits will remain the same after the proposed expansion. The mass TSS limitations will remain the same after the proposed expansion. The monthly average phosphorus limit (2 mg/l) will be changed to a more stringent monthly average limit (1 mg/l) and the mass concentrations of phosphorus discharged to the Minnesota River will remain the same. Limits for ph and dissolved oxygen will also remain the same after the expansion. (Wastewater impacts are discussed in Section 18.) As discussed in Section 12, the proposed wastewater treatment system expansion will not involve the physical or hydrologic alteration of any surface waters. The proposed project will increase water use by about seven percent. This is within Rahr Malting s current water appropriation permit (discussed in Section 13). Fish, Wildlife, and Ecologically Sensitive Resources. While fish, wildlife, and ecologically sensitive resources do not exist on the proposed project site, they do exist in areas adjacent to the project. Rahr Malting requested a Natural Heritage Database review from the DNR to identify the presence ecologically sensitive resources in the vicinity of the project. Based on the type of rare plant or animal species or other significant natural features identified and their location, the proposed project is not expected to adversely affect these resources. Solid Wastes, Hazardous Wastes, Storage Tanks The proposed project will involve the generation of solid wastes during construction and during ongoing operations. The proposed project will generate sludge and ash. Rahr Malting has obtained a permit for the land disposal of sludge and Koda Energy is exploring beneficial uses for the ash. Koda Energy will have a 15,000-gallon urea tank to provide reagent for the Selective Noncatalytic Reduction system to control NO X inside the boiler building. Solid wastes, hazardous materials and storage tanks are discussed in Section 20. Odors, Noise, and Dust Project construction has the potential to generate noise and dust. (Section 24 discusses measures to reduce noise and dust during construction and measures to control ongoing odors, noise and dust.) Visual Impacts The construction of large buildings has visual impacts both during construction and operation. Construction will occur on an industrial site and the new buildings will be smaller than existing 11

13 buildings. A visibility analysis evaluated the impacts on the Minnesota River Valley. (This is discussed in Sections 23 and 26.) Indirect Impacts Malt byproducts, produced on site, will provide approximately 30 percent of the fuel for the proposed heat and power plant. These are currently shipped off site (North Dakota or Duluth) as a low-grade amendment to animal feed. Oat hulls, from local processing facilities will provide approximately 35 percent of the fuel. These are also currently shipped offsite as a low-grade amendment to animal feed. Sawdust and wood shavings available within a 50-mile radius will provide another, approximately 35 percent of the fuel. These are currently used for animal bedding, fuel, or mulch. By using locally produced food processing byproducts and wood residues instead of shipping materials to distant markets, the proposed project will reduce total truck miles traveled by over 860,000 miles per year. Greenhouse Gas Emissions Greenhouse gas emitting fuels account for a significant amount of Minnesota s electrical power. In 2003, according to the Department of Energy Information Administration, coal accounted for 65.3 percent of Minnesota electrical energy while other fossil fuels accounted for an additional 4.6 percent. Renewable fuel sources such as hydroelectric, wind, solid waste, landfill gas, and wood accounted for 5.1 percent. Nuclear energy provided 25 percent of Minnesota s electrical power. Koda Energy uses biomass, which is considered carbon neutral, to replace natural gas that is currently used to produce 120,000 lbs/hr of steam. Koda Energy will also produce up to 17.8 MW of electricity, replacing electricity currently produced by 70 percent fossil fuels (and 25 percent nuclear and 5 percent renewable). If this proposed expansion does not go forward, Rahr Malting will continue to burn natural gas to produce steam and will continue to purchase electricity produced in large part by fossil fuels. c. Explain the project purpose; if the project will be carried out by a governmental unit, explain the need for the project and identify its beneficiaries. Rahr Malting is proposing to expand the wastewater treatment plant to treat additional process wastewater. The proposed wastewater treatment system expansion will eliminate discharge to the MCES Blue Lake Facility. Rahr Malting will benefit from this project through lower wastewater treatment costs. Koda Energy will generate up to 17.8 MW of baseload electricity while delivering 125 MMBtu/hr (120,000 lbs steam) of process heat to Rahr Malting. Koda Energy will produce enough heat from biomass to replace all of the natural gas needed for Rahr Malting s processes. Cogeneration is a highly efficient process, converting more fuel to energy than either electricity or steam generation alone. d. Are future stages of this development including development on any outlots planned or likely to happen? Yes No If yes, briefly describe future stages, relationship to present project, timeline and plans for environmental review. e. Is this project a subsequent stage of an earlier project? Yes No If yes, briefly describe the past development, timeline and any past environmental review. 12

14 7. Project Magnitude Data Total Project Area (acres) 18 or Length (miles) 0 Number of Residential Units: Unattached 0 Attached 0 Maximum Units Per Building: 0 Commercial/Industrial/Institutional Building Area (gross floor space): total square feet Indicate area of specific uses (in square feet): Office 0 Manufacturing 0 Retail 0 Other Industrial < 4.3 Acres Warehouse 0 Institutional 0 Light Industrial 0 Agricultural 0 Other Commercial (specify) 0 Building height 140 If over 2 stories, compare to heights of nearby buildings 280 Table 1 Proposed Project Magnitude Data Rahr Malting Wastewater Treatment Expansion and Koda Energy Combined Heat and Power Plant Total Area (acres) ~ 4.3 Residential Units Commercial/Industrial/Institutional Building Area (floor space in square feet) N/A Approximately 85,000 Maximum Building Height (feet) above grade 140 The Rahr Malting site covers 18 acres and includes 46 buildings ranging in height from approximately 25 feet to 280 feet. The existing wastewater treatment system occupies 37,900 square feet. The proposed wastewater treatment system expansion will increase the total area to 56,000 square feet. The tallest proposed building height is 25 feet above existing grade. The proposed heat and power plant will occupy 2.3 acres on property leased from Rahr Malting. The tallest building will be 140 feet and the tallest structure (the boiler exhaust stack) will be 220 feet. No new property will be acquired or developed for the proposed wastewater treatment system expansion or the proposed heat and power plant. The proposed project will be built within the footprint of the Rahr Malting property. 13

15 8. Permits and approvals required. List all known local, state and federal permits, approvals and financial assistance for the project. Include modifications of any existing permits, governmental review of plans, and all direct and indirect forms of public financial assistance including bond guarantees, Tax Increment Financing and infrastructure. Proposed Wastewater Treatment System Unit of Government Type of Application Status MPCA NPDES/SDS Permit Modification Submitted, under review MPCA Plans and Specifications Review To be submitted MPCA NPDES General Stormwater Permit To be submitted (Construction Activities) MPCA NPDES General Stormwater Permit To be submitted (Industrial) Shakopee Building Permit To be submitted Shakopee Plat Amendment Approved Watershed District Approval Review and Comment To be requested Proposed Heat and Power Plant Unit of Government Type of Application Status MPCA Non-Contact Cooling Water To be submitted MPCA Air Permit/Prevention of Significant Pending Deterioration (PSD) MPCA NPDES General Stormwater Permit To be submitted (Construction Activities) MPCA NPDES General Stormwater Permit To be submitted (Industrial) Building Permit To be submitted DNR Water Appropriation Permit amendment To be submitted Shakopee Shakopee Plat Amendment Approved Review and Comment To be requested Watershed District Approval Combined Project Unit of Government Type of Application Status DNR Natural Heritage and Nongame Submitted, under review Database Review SHPO Concurrence on Findings of Cultural Completed Resource Impacts Watershed District Approval Review and Comment To be requested 14

16 9. Land use. Describe current and recent past land use and development on the site and on adjacent lands. Discuss project compatibility with adjacent and nearby land uses. Indicate whether any potential conflicts involve environmental matters. Identify any potential environmental hazards due to past site uses, such as soil contamination or abandoned storage tanks, or proximity to nearby hazardous liquid or gas pipelines. The Shakopee zoning plan classifies the entire 18-acre Rahr Malting site (which includes both project sites) as Zone 12-heavy industrial. The site is bordered: to the north by Zone Ag-agricultural (primarily the Minnesota River Valley, which is mostly trees); to the south by Zones 11-light industrial, R3-mid density residential, and R2-urban residential; to the east by zone B1 - highway business; and to the west by Zones Ag, B1, and 11. The site is also located in an industrial area based on Shakopee land development plans (Shakopee 2020 Comprehensive Plan 1999). Based on the zoning and land development plan, both projects are compatible with, and, therefore, do not conflict with, surrounding land uses. Rahr Malting has been located in Shakopee since The Rahr family has controlled the property for the past 70 years. Rahr Malting has added processing and storage equipment to the facility, as needed, to update and maintain the facility on several occasions since The proposed wastewater treatment system expansion and the proposed heat and power plant will both be located on the existing Rahr Malting site and do not require any expansion of the existing site. In the past, the proposed locations were used as staging and storage areas during previous projects and as haul roads, storage, and parking. The proposed locations are currently unoccupied (see Exhibits 3 and 4). The proposed wastewater treatment system expansion will be constructed directly adjacent to the existing wastewater treatment system. The proposed wastewater system expansion incorporates processes similar to what exists at the site. The proposed heat and power plant, including materials handling processes, will be located adjacent to Rahr Malting in an area that previously included haul roads, parking areas, storage, and office buildings. 10. Cover Types. Estimate the acreage of the site with each of the following cover types before and after development: Before After Before After Types 1-8 wetlands 0 0 Lawn/landscaping 6 6 Wooded/forest 0 0 Impervious Surfaces Brush/grassland 0 0 Other (describe) 2.3 (Industrial Space) Cropland TOTAL (Industrial Space) 15

17 11. Fish, Wildlife, and Ecologically Sensitive Resources. a. Identify fish and wildlife resources and habitats on or near the site and describe how they would be affected by the project. Describe any measures to be taken to minimize or avoid impacts. There is very limited habitat area on this existing industrial site. Industrial occupation for over 70 years has left very little pre-development habitat undisturbed. Existing cover (gravel haul roads and parking areas, metal storage, mown field) and soil types provide poor wildlife habitat. Rahr Malting has occupied this site since No original cover, very little original soil, and no undisturbed pre-development habitat exist. During the 70 years of occupation by Rahr Malting, construction activities have mixed considerable amounts of clayey sand and silty sand fill, aggregate, and gravel in with the original soils (HeB loamy fine sand). Truck, heavy equipment, and other vehicle traffic have compacted the soils. Recent activities on the proposed heat and power plant location included metal storage, storage buildings, a trucker s lounge, parking and roads. The Minnesota River Valley provides habitat to aquatic and terrestrial flora and fauna. The valley has floodplain wetlands, wet meadows, fens, and lakes. Wetlands are replenished by the river and by spring-fed streams draining the landscape. The Minnesota Valley National Wildlife Refuge is located on the Minnesota River, less than two miles downstream from Rahr Malting. Stormwater from Rahr Malting is treated in a settling basin and discharged to the Minnesota River. The process water discharged to the Minnesota River from the facility will meet tertiary treatment standards and will not increase loadings above existing permitted levels. Rahr Malting and a four-lane roadway (formerly Trunk Highway 169) buffer the proposed project site from the Minnesota River Valley. The Wilkie Unit of the Minnesota Valley National Wildlife Refuge is located on the Minnesota River, seven miles downstream from the proposed heat and power plant. The proposed Upgrala Unit of the Minnesota Valley National Wildlife Refuge is located two miles downstream from the proposed project. The proposed heat and power plant will not impact the Wilkie, the proposed Upgrala unit or other downstream units of the Minnesota River Valley National Wildlife Refuge. The Louisville Swamp and Chaska Lake Wildlife Refuges are located approximately five miles upstream from the proposed heat and power plant. Koda Energy will emit small amounts of bioaccumulative and toxic chemicals (PBTs). These compounds could enter the food chain via Rice Lake and Nussens Lake and are located closer to Koda Energy than Lake Riley. Based on information from the DNR, these lakes are classified as Type 4/5 wetlands and cannot support a sustainable fish population, nor are they readily accessible to the public. PSD Class I Areas refer to areas with pristine air quality, such as wilderness areas, national parks, and Native American reservations, and are accorded strict protection. Only very small incremental increases in concentration are allowed in order to maintain the very clean air quality in these areas. The nearest Class I wilderness area is the Rainbow Lakes National Wilderness area, located approximately 250 kilometers from Koda Energy. 16

18 PSD Class II Areas include all areas that are not designated Class I are designated Class II. Moderate incremental increases in ambient concentration of regulated pollutants are allowed, although the concentrations are not allowed to reach the concentrations set by Minnesota and federal standards (Minnesota Ambient Air Quality Standards and National Ambient Air Quality Standards, or MAAQS and NAAQS, respectively ). The Air Modeling Impact Assessment demonstrated compliance with MAAQS and NAAQS. Based on the information provided above, the proposed project is not expected to negatively affect the Minnesota River, fish, wildlife, or habitats located on or near the site. b. Are any state (endangered or threatened) species, rare plant communities or other sensitive ecological resources such as native prairie habitat, colonial waterbird nesting colonies or regionally rare plant communities on or near the site? Yes No If yes, describe the resource and how it would be affected by the project. Indicate if a site survey of the resources has been conducted and describe the results. If the DNR Natural Heritage and Nongame Research program has been contacted give the correspondence reference number: ERDB Describe measures to minimize or avoid adverse impacts. A DNR Natural Heritage and Nongame Research database review was conducted for the proposed project in April 2007 (see Exhibit 4). The purpose of the review was to check for the existence of a rare plant or animal species, or other significant natural features near the project. Based on this review, there are no known occurrences of rare species or natural features in the immediate vicinity. The review found no known occurrences of rare plant or animal species or other significant natural features on the proposed project site. The Natural Heritage Database Review identified 12 occurrences of rare or threatened species in the vicinity of the proposed project. Listed occurrences include 2 fish species, 7 mussel species, 1 snake species (last observed in 1932), 1 bald eagle nesting site, and a calcareous seepage fen in Carver County. The Natural Heritage Database review identified occurrences of several rare aquatic species (primarily Mussels) located in the Minnesota River valley to the west, north, and northeast of the proposed heat and power plant. Combustion sources can adversely impact aquatic species through deposition of bioaccumulative substances such as mercury. The closest waterbody to the proposed heat and power plant is the Minnesota River, which will not accumulate significant levels of toxics due to the constant flow of water. Other waterbodies in the vicinity are classified as Type 4 and Type 5 wetlands along the Minnesota River and cannot sustain fish populations. In addition, these wetlands flood frequently. Frequent flooding reduces the potential for bioaccumulation. The closest waterbody to the project where mercury and other pollutants potentially deposited by the proposed heat and power plant biomass boiler could accumulate is Lake Riley and it is not a habitat for any of the identified endangered/threatened aquatic species. 17

19 The Bald Eagle (Haliaeetus leucocephalus) is listed as threatened under the Endangered Species Act and did appear in the Natural Heritage Database. An active Bald Eagle nest was last observed in the vicinity in This species has the potential to nest within three kilometers of the proposed project site. Natural Heritage Database reviews also identified the gopher snake (or bullsnake) as a rare animal species in the vicinity of the project. The database indicates that one specimen was collected in Shakopee in Gopher snakes live in prairies, open forests (usually pine and oak), pastures, and brushlands. They eat mice, rabbits, gophers, ground squirrels, birds, and bird eggs. Their range runs from central to southeastern Minnesota, particularly in areas that have sandy soil and open grasslands. Most potential habitat in the vicinity has been developed. Other potential habitat lies in the Minnesota River floodplain where frequent flooding reduces the accumulation of toxins. Based on the type of rare plant or animal species or other significant natural features identified and their location, the proposed project is not expected to adversely affect these resources. 12. Physical Impacts on Water Resources. Will the project involve the physical or hydrologic alteration (dredging, filling, stream diversion, outfall structure, diking, and impoundment) of any surface waters such as a lake, pond, wetland, stream or drainage ditch? Yes No If yes, identify water resource affected. Describe alternatives considered and proposed mitigation measures to minimize impacts. Give the DNR Protected Waters Inventory (PWI) number(s) if the water resources affected are on the PWI. The proposed project will not require dredging, filling, stream diversion, diking, or impoundment. Historically, the proposed 4.3-acre site consisted of storage buildings, gravel roadway, and parking areas and compacted fill, gravel, and clayey soil. The proposed project will pave roadways and parking areas to minimize fugitive air emissions. These changes will reduce loading of total suspended particulates to stormwater but may increase the rate of runoff. The area on which the proposed wastewater treatment system will be located is considered impervious (refer to item 10 for a discussion of stormwater). Stormwater will be retained in a detention basin on site, and released after treatment; therefore, there will be little if any increase in the volume of surface water runoff from the site. To control the rate of runoff and provide treatment, Koda Energy will construct a stormwater detention basin with approximately 0.5-acre-feet of storage. The detention basin will mitigate any potential increases in stormwater flow prior to discharge to the city of Shakopee storm sewer. The present outfall structure will be used for the proposed expansion of the wastewater system. The current discharge outfall is at river mile 25.3 (refer to item 19 for a discussion of the wastewater discharge). 13. Water Use. Will the project involve installation or abandonment of any water wells, connection to or changes in any public water supply or appropriation of any ground or surface water (including dewatering)? Yes No If yes, as applicable, give location and purpose of any new wells; public supply affected, changes to be made, and water quantities to be used; the source, duration, quantity and purpose of any appropriations; and unique well numbers and DNR appropriation permit numbers, if known. Identify any existing and new wells on the site map. If there are no wells known on site, explain 18

20 methodology used to determine. A Water Appropriation Permit is required for all users withdrawing more than 10,000 gallons of water per day or one million gallons per year. The purpose of the permit program is to ensure water resources are managed so that adequate supply is provided to long-range seasonal requirements for domestic, agricultural, fish and wildlife, recreational, power, navigational, and quality control. The program exists to balance competing management objectives including both the development and protection of the water resources. Information on permitted water users and reported water use is used to evaluate impacts from pumping on surface and ground-water resources. Water use data are also used for water supply planning and resolving water use conflicts and well interferences. The DNR administers this permit and requires monthly usage monitoring and annual reporting to ensure that surrounding communities and industries water supplies will not be affected by draw-down of the aquifer. Minn. Stat. 103G.261 establishes domestic water use as the highest priority of the state s water when supplies are limited. The proposed project will not involve the installation or abandonment of any water wells and will not impact the public water supply. The DNR has issued Water Appropriation Permit to Rahr Malting, which covers five installations with a permitted appropriation of 1.14 billion gallons per year. The appropriation of water for the proposed wastewater treatment system expansion is within the current permitted levels. Rahr Malting will provide water, by contract, to Koda Energy. Koda Energy will require makeup water to replace water used for a variety of plant processes. The most significant water uses are: Boiler blowdown losses Cooling tower losses Reverse Osmosis unit effluent Koda Energy will require approximately 150 gpm of water to make up for losses in the system. Boiler Blowdown Losses The boilers will continuously discharge and replace a small portion of the water in the system to maintain water and steam quality. A portion of this water is flashed off as steam or lost through various steam vents. The rest is discharged. The proposed heat and power plant will require up to 21.0 gpm to make up boiler losses. Cooling Tower Losses Cooling towers lose water through evaporation, drift (water entrained in the discharge vapor), and blowdown loss (water discarded to release solids). Under full load, the cooling tower (assuming warm weather conditions and operation at maximum capacity) will require gpm. The majority of this water replaces water evaporated by the system and water lost through drift. 19

21 Reverse Osmosis Unit Effluent The proposed heat and power plant will use a reverse osmosis unit to treat cooling tower and boiler makeup water and water used to replace various plant losses. The reverse osmosis unit will require an average of 2.7 gpm to make up losses. Use of the reverse osmosis unit reduces the amount of blowdown water required. Rahr Malting currently uses approximately 85 percent of its 1.14 billion gallon appropriation and Koda Energy will require approximately 150 gpm for operations at the proposed heat and power plant (7 percent of the annual appropriation). This additional use is within the current permitted levels. The DNR has indicated that Rahr Malting will need to amend its Water Appropriation Permit to allow non-agricultural use of the water. The permitted water appropriation will not increase. 14. Water-related land use management districts. Does any part of the project involve a shoreland zoning district, a delineated 100-year floodplain, or a state or federally designated wild or scenic river land use district? Yes No If yes, identify the district and discuss project compatibility with district land use restrictions. Shoreland Management The Scott County Zoning Ordinance Chapter 70 Shoreland District lists natural environment lakes, recreational development lakes, general development lakes, agricultural rivers (the Minnesota River), transition rivers and tributary rivers. The ordinance specifies minimum lot width, the building setback line and the ordinary high water level on lots abutting classified public waters. The Rahr Malting and Koda Energy property does not abut any classified public waters and, therefore, the shoreland ordinance does not apply. Floodplain Management Based on a review of the Scott County Federal Emergency Management Agency Floodplains map (tracking number 2.4.1), the Minnesota River Valley immediately north of Trunk Highway 69 is delineated as a 100-year floodplain, but the Rahr Malting and Koda Energy property is not in the floodplain, and neither will alter, change, or impact the 100-year floodplain. 15. Water Surface Use. Will the project change the number or type of watercraft on any water body? Yes No If yes, indicate the current and projected watercraft usage and discuss any potential overcrowding or conflicts with other uses. 16. Erosion and Sedimentation. Give the acreage to be graded or excavated and the cubic yards of soil to be moved: 4.3 acres; < 20,000 cubic yards. Describe any steep slopes or highly erodible soils and identify them on the site map. Describe any erosion and sedimentation control measures to be used during and after project construction. The slope over the entire proposed project area is less than two percent. The proposed wastewater treatment system expansion and the proposed heat and power plant will be built separately by different contractors. Each project component will require and will obtain a stormwater construction permit. 20

22 The original soils on site are undulating erosional and depositional surface covered by fine, wind deposited sand and silt. The U.S. Department of Agriculture published the most recent Scott County Soil Survey in The survey represents field conditions when the survey was completed in It identified the soils on the site as Hubbard loamy fine sand with 2 to 6 percent slope (HeB). Although these soils are considered erodible, since originally locating on the site in 1936, Rahr Malting has leveled the site, constructed aggregate haul roads and parking areas, built storage and process buildings, and in other ways significantly modified the original soils. Subsurface explorations conducted for Kiln 7 and Malt House 5 in 1992 and for the wastewater treatment facility in 1997 indicate that the location of the proposed heat and power plant is covered by three to five feet of fill. The fill is a mixture of silty sand and clayey sand. This fill also shows traces of gravel and some limestone inclusions throughout. A General Construction Stormwater Permit is required when a project disturbs one or more acres. It requires the use of BMPs, such as silt fences, bale checks, and prompt re-vegetation to prevent eroded sediment from leaving the construction site. The project proposer must have a sediment and erosion control plan that will address phased construction, vehicle tracking of sediment, inspection of erosion control measures implemented, and time frames in which erosion control measures will be implemented. The general permit also require adequate stormwater treatment capacity be provided to assure that water quality will not be impacted by runoff once the proposed project is constructed. Each project component will require its own SWPP. The prime contractor for each component will be responsible for implementing the component s stormwater construction permit. The construction operators will provide practices such as temporary diversions, hay bails, and silt fences during construction, where appropriate. According to the MPCA staff experience, the BMPs required for the proposed project are effective at mitigating the stormwater runoff. Proposed Wastewater Treatment Expansion Rahr Malting will be required to obtain an NPDES General Stormwater Permit for Construction Activities from the MPCA to control erosion and runoff during construction. This permit must be obtained before land disrupting activities begin. The permit requires the implementation of best BMPs. Construction plans will include BMPs such as the following: Scarifying only those portion of the site actively under construction Interim grading of slopes and piles will have no greater than 3:1 slopes Inlet protection for all nearby or adjacent stormwater inlets Perimeter silt fencing Proposed Heat and Power Plant Because the disturbed area for the proposed site for the proposed heat and power plant is over one acre, construction will require a MPCA General Stormwater Permit for Construction Activity. An SWPPP will be required as a condition of the permit. The contractor will implement the SWPPP during construction. This plan will use BMPs to prevent excessive erosion during construction and will comply with the General Stormwater Permit. The General Stormwater Permit will be effective throughout the 365-day construction process. New impervious surfaces constructed will include the buildings and on-site roadways. The construction operators will provide practices such as temporary diversions, hay bails, and silt fences during construction, where appropriate. The completed site will use a permanent stormwater detention basin to manage stormwater and prevent silt from leaving the project site. Where practical, nonimpervious surfaces will be planted with grass or other vegetation or covered to minimize erosion. 21

23 17. Water Quality Surface-water Runoff. a. Compare the quantity and quality of site runoff before and after the project. Describe permanent controls to manage or treat runoff. Describe any storm-water pollution prevention plans. The Rahr Malting SWPPP covers the proposed wastewater treatment system expansion and proposed heat and power plant locations. The Rahr Malting SWPPP focuses on control of the potential for stormwater pollution as a result of grain loading and unloading operations. High pollution potential areas identified in the Rahr Malting SWPPP include receiving areas, loadout areas, transfer points and air emissions points. Identified sources of pollution include spillage from trucks, rail cars, and loading equipment. Activities at the proposed wastewater treatment system expansion and the proposed heat and power plant that may contaminate stormwater are consistent with those described in the Rahr Malting SWPPP, and the measures in the Rahr Malting SWPPP are appropriate measures for controlling these potential stormwater contaminant sources. Measures identified include weekly sweeping (now twice weekly), more frequent sweeping of high exposure areas, inspection and maintenance of air pollution control equipment, covered loading and unloading areas, indoor storage of chemicals, secondary containment for all gasoline and fuel oil tanks, and a detention pond. An existing detention pond treats stromwater from the Rahr Malting site prior to discharge to the Minnesota River. This pond treats stormwater from the wastewater treatment system and will treat stormwater runoff from the proposed wastewater treatment system expansion. This detention pond will also treat stormwater from the north and west of the proposed heat and power plant location. A second detention pond is planned for the proposed heat and power plant. The second stormwater basin will treat stormwater from the majority of the proposed heat and power plant location prior to discharge to a city of Shakopee storm sewer. b. Identify routes and receiving water bodies for runoff from the site; include major downstream water bodies as well as the immediate receiving waters. Estimate impact runoff on the quality of receiving waters. Stormwater runoff from the wastewater treatment system site and the north and west portion of the proposed heat and power plant location discharges to a stromwater detention basin that discharges to the Minnesota River. The impact of runoff water should not change with the proposed project. The stormwater from the majority of the proposed heat and power plant location discharges to a detention basin that discharges to a city of Shakopee storm sewer and then to the Minnesota River. 18. Water Quality Wastewater. a. Describe sources, composition and quantities of all sanitary, municipal and industrial wastewater produced or treated at the site. Proposed Wastewater Treatment Expansion The Rahr Malting wastewater treatment system is permitted under the NPDES/SDS Permit Program for the discharge of non-contact cooling water and wastewater. An NPDES/SDS Permit Amendment will be prepared for the proposed expansion and issued by the MPCA following a 30-day public 22

24 comment period. The NPDES/SDS Permit authorizes a discharge of pollutants from the proposed wastewater treatment system expansion. Effluent limitations are established within the permit pursuant to state and federal statutes, rules, and regulations. Rahr Malting treats 66 to 75 percent of its process wastewater in the existing wastewater treatment facility and discharges to the Minnesota River under the conditions included in the permit. The remaining 25 to 33 percent of the Rahr Malting process wastewater is discharged to the city of Shakopee s wastewater collection system for treatment at the MCES Blue Lake Facility. The proposed expansion is being designed as a parallel treatment system to the existing SBR system. The existing system is currently treating an average of approximately 1.5 MGD with an influent CBOD 5 strength of 630 mg/l. The limit of 68 kg/day average of CBOD 5 (150 lbs) in the existing NPDES/SDS Permit represents the amount gained from a 1997 trading agreement between the MPCA and Rahr Malting. The proposed increase of CBOD 5 to 96.5 kg/day average represents the NPS load reduction units that Rahr Malting obtained during the term of the existing NPDES/SDS Permit. The proposed daily ammonia limits are the same as the limit included in the 1997 NPDES/SDS Permit. The proposed plant expansion will increase the annual average capacity to MGD and the AWW/peak daily/phww flow rates will increase to 2.41 MGD. The flow rates for the plant expansion were determined from review of the malting process, available raw waste flow equalization, and planned flows from the proposed heat and power plant. Rahr Malting processes barley in five malt houses. Processing involves steeping the barley in either a high volume steep (submerged in water) or a low volume steep (sprayed with water). After accounting for evaporative losses, the two processes generate a low flow of 1.18 MGD (all five malt houses at the low volume steep rate) and a high flow of 2.34 MGD (four malt houses (80 percent) at high volume and one malt house (20 percent) at low volume steep rate). Process wastewater from the malt houses discharge to a central location and equalized in a 328,000-gallon tank to eliminate hydraulic surges. The process wastewater from the malting complex is pumped to the existing process wastewater treatment facility s screenings/lift station. The overflow from this equalization basin currently discharges to the city of Shakopee sanitary sewer system. The expanded wastewater treatment system will eliminate this overflow. A second influent equalization basin, with a 362,000-gallon volume, feeds the SBR four times per day and will also feed the expanded portion of the wastewater treatment system on a continuous basis. Proposed Heat and Power Plant The flows from Koda Energy will vary between a low flow rate of (5 gpm) to a high flow rate of (50 gpm) with an anticipated average flow rate of (37 gpm). The high flow rate of MGD will be used for determining the total flow rate for the process wastewater treatment plant expansion. Table 2 summarizes the influent design parameters for the wastewater treatment facility. 23

25 Table 2 Annual Average Projected Influent Wastewater Flows and Loadings Parameter Design Criteria Influent Concentration Daily Flow Average Wet Weather/Peak daily/peak Hourly Wet Weather Flow Rate 2.092MGD 2.41 MGD TSS 1,685 lb/day 100 mg/l CBOD 5 10,614 lb/day 630 mg/l Ammonia 123 lb/day 7.3 mg/l Nitrogen (TKN) 472 lb/day 28 mg/l Phosphorus 137 lb/day 8.1 mg/l The only sources of sanitary wastewater produced at the heat and power plant will be for restrooms and sinks. Rahr Malting is connected to the city of Shakopee s sanitary sewer system and both have sufficient capacity for the amount of sanitary wastewater that will be produced by this proposed project. Koda Energy will discharge process wastewater to the Rahr Malting wastewater treatment facility from the following sources: Boiler blowdown Cooling tower blowdown Reverse Osmosis unit effluent. Koda Energy will discharge 72,000 gallons per day to the Rahr Malting wastewater treatment facility. This is 3.6 percent of the wastewater treatment facility s daily permitted discharge of MGD. Koda Energy will use up to 150 gpm of well water and will discharge 50 gpm of boiler blowdown, cooling tower blowdown, and reverse osmosis reject water. Most of the losses result from evaporation in the cooling tower and the release of steam. The well water used in Koda Energy process is the same well water that Rahr Malting uses in its processes. 24

26 Table 3 provides the results from an August 13, 2006, test of Well 5: Table 3 Rahr Malting Well Water Composition Well Water Unit TSS <2 mg/l ph 7.5 Coliform <1 CFU/100 ml Nitrogen, ammonia 0.02 mg/l Phophorus, total 0.2 mg/l Chemical Oxygen Demand 5 mg/l Nitrogen, Total Kjeldahl 0.3 mg/l Total solids 544 mg/l Total Solids, Dissolved 417 mg/l Total Solids, Volatile 246 mg/l Solids, Suspended Volatile <2 mg/l Calcium 84.9 mg/l Magnesium 34.3 mg/l Sodium 10.1 mg/l Chromium mg/l Copper mg/l Iron 0.01 mg/l Magnanese mg/l Silicon 21.8 mg/l Lead <0.5 ug/l The ph of the well water is within the range of the permit limits ( ). Table 4 average daily flows, and influent parameters of the Koda Energy boiler blowdown, cooling tower blowdown, and reverse osmosis reject water: Table 4 Summary of Koda Energy Non-Contact Cooling Water Flows and Loadings Design Criteria Influent Concentration Parameter Average Daily Flow MGD Average Wet Weather Flow NA Maximum Daily Flow MGD TSS 3.6 lb/day 6 mg/l Chemical Oxygen Demand 9.0 lb/day 15 mg/l Ammonia 0.04 lb/day 0.06 mg/l Nitrogen (TKN) 0.54 lb/day 0.9 mg/l Phosphorus 0.36 lb/day 0.6 mg/l b. Describe waste treatment methods or pollution prevention efforts and give estimates of composition after treatment. Identify receiving waters, including major downstream water bodies, and estimate the discharge impact on the quality of receiving waters. If the project involves on-site sewage systems, discuss the suitability of site conditions for such systems. 25

27 Existing Wastewater Treatment System. Currently, process wastewaters are collected at a central location and equalized in a 328,000-gallon tank to eliminate hydraulic surges. The existing wastewater holding tank has the capacity to equalize hydraulic discharges from all five houses. Two 2,150-gpm pumps pump the wastewater to the existing two-millimeter rotary screen that removes particles longer than this diameter and fibrous material. The screen process water is then pumped to a 362,000-gallon equalization tank that is used to batch feed the single 1.5-million gallon SBR. After treatment in the SBR, the effluent is batch fed into a 522,000-gallon effluent equalization basin before final filtration, re-aeration, and discharge to the Minnesota River. Proposed Process Wastewater Treatment System The process wastewater treatment system expansion will install an MBR to run in parallel with the existing SBR system. The proposed wastewater treatment system expansion is being designed to handle an average daily flow of 1.5 MGD and a peak instantaneous flow rate of 2.25 MGD. The proposed wastewater expansion system consists of the following components: biological treatment system (activated sludge process) and membrane filtration system. Activated Sludge Process The process wastewater will be pumped from the existing screening process wetwell and be split between the two activated sludge systems (MBR and SBR). The new MBR treatment system will consist of three concrete reactor tanks and three membrane tanks. Each reactor tank has interior dimensions of 44 feet by 67.5 feet by 23 feet. Three positive displacement blowers, with a capacity to supply 3,060 SCFM at 11 psig, will provide aeration to the tanks. Two blowers will operate and one will be on standby. Each tank will contain fine bubble diffusers for the transfer of oxygen to the wastewater. The mixed liquor (the mix of raw water and activated sludge) will flow by gravity to three membrane tanks. Membrane Filtration The membrane system is composed of hollow-fiber membrane modules submerged on racks in three concrete tanks. Each tank has inner dimensions of 14 feet in length by 13 feet in width by 8, feet 3 inches in height. The membrane system contains a total of 160 membrane modules; the modules are housed on 10 racks (16 modules per rack). Water is drawn through the membranes by a suction developing filtrate pump. There are three filtrate suction pumps each with a capacity to pump gpm at 25-foot total dynamic head. Particles greater than 0.1 µm are filtered out of the water. Mixed liquor is returned back to the activated sludge tanks continuously using three pumps through a common manifold. Changes in effluent flow rates are provided using a variable frequency drive on the filtrate pumps and mixed liquor return pumps. Membrane Cleaning Procedure Membrane fouling is mitigated through four processes: air-lift scouring, membrane relaxation period, a weekly chlorinated backwash cleaning, and a chemical cleaning. The air-lift scouring is incorporated 26

28 into the delivery of mixed liquor to the membrane tanks and scours particles from the surface of the membrane. The air-lift jets are located below each module and send a combination of turbulent air and mixed liquor in an upward and parallel direction to the membrane modules. Three positive displacement blowers are used in the component of the system; each blower has the capacity to deliver 1,100 SCFM at 4.2 psig. The second step of automatic membrane maintenance is the relaxation step. Approximately every 12 minutes a one-minute relaxation period occurs, during which the filtrate pumps stop creating suction through the membranes. The air scouring and mixed liquor flows continue during this period to remove particulate buildup. The third step of maintenance is a weekly disinfecting backwash. This disinfection provides interim disinfection of the membranes and filtrate pipe work between chemical cleans. During this cleaning procedure, the filtrate pumps are stopped and chlorinated filtrate is pumped backwards through the filters. The mixed liquor and air-lift feed pumps continue during this cleaning process. The fourth maintenance step is a chemical cleaning. This process is similar to the disinfecting backwash except for the strength of the solution used. 1,500 mg/l of sodium hypochlorite or a 2 percent citric acid chemical solution is used. This process typically occurs every 90 to 180 days and initiation is dictated when the membranes reach a maximum allowable pressure differential. Wastewater Sampling Automatic sampling equipment is used to collect composite samples of both the influent raw waste and the treated effluent. Routine analysis of CBOD 5, TSS, nitrogen compounds and phosphorus are required for process control, along with monitoring of MLSS and dissolved oxygen. The same parameters plus dissolved oxygen, ph, and temperature are monitored for compliance with the NPDES/SDS Permit. The system is fully automated. A plant-wide alarm is provided to alert personnel of problems needing immediate attention. For normal operation, the plant is staffed by one person with a Class A wastewater operator s license. Each day, the operator checks the process, performs operational tests, delivers samples to the quality control laboratory for analysis, and prepares the paperwork required for the Discharge Monitoring Reports to the MPCA. Industrial Byproduct Management Rahr Malting is currently land applying its waste activated sludge (WAS) under SDS General Permit No. MN , Authorization to Land Apply Wastes from Food and Beverage Processing Facilities. Rahr Malting currently has a contract with Mountain Environmental, Inc. for hauling and land application and utilization of this industrial byproduct. Mountain Environmental, Inc. currently has five Type IV certified operators managing the land application of the industrial byproduct. The existing SBR treatment process produces approximately 85,000 gpd at 1.0 percent of waste industrial byproduct. The industrial byproduct is pumped to the existing 870,000-gallon aerated storage basin. The storage basin is equipped with jet aeration and is provided with a decant system. It is estimated that the MBR treatment process will increase the volume of waste industrial byproduct by 45 percent to a daily total volume of waste byproduct to 123,000 gallons per day at 1.0 percent. 27

29 Rahr Malting has installed one two-meter belt press for dewatering the industrial byproduct prior to land application and reuse. The belt press was installed to reduce the trucking costs associated with the hauling of one percent solids. Mountain Environmental, Inc. has the equipment and land available to land apply a one percent industrial byproduct should the need arise. Rahr Malting is currently dewatering the industrial byproduct prior to land application 5 days per week for 7.5 hours per day. With the additional waste byproduct, it is anticipated that the pressing operation will require 10.5 to 11 hours per day for the 5 days per week. The yearly total nitrogen in the existing industrial byproduct is approximately 90,000 pounds per year. The yearly total nitrogen in the proposed process wastewater is estimated at approximately 132,300 pounds per year. Using an application rate of 120 pounds of nitrogen per acre, a yearly total of 1,103 acres will be required for the combined process wastewater treatment systems. The winter application period from November 15 through March 31 will require 415 acres at the 120 pounds of nitrogen per acre. Mountain Environmental, Inc. has a total of 1,520 acres available for the application of Rahr Malting s industrial byproduct. Of the total acres available for land application of the industrial byproduct, 800 acres meet the requirements for winter application of industrial byproducts. Reliability The MPCA s Reliability for Mechanical Wastewater Treatment Plants criteria, requires that, where duplicate units are provided, each unit operation must be designed such that, with the largest unit out of service, the hydraulic capacity of the interconnecting piping will be sufficient to transport the peak instantaneous wet weather flow (PIWW - as defined in MPCA "Design Flow Determination" guidance) through the remaining units. Where duplicate units are provided, a single flow splitting device must be provided before each unit operation. To comply with this criterion, the proposed wastewater treatment system expansion (MBR) needs to have a hydraulic capacity in excess of the malt house PIWW flow; in conjunction with available raw wastewater storage in the malt house and at the wastewater treatment system. The SBR process has a hydraulic design of 1.5 MGD. The MBR process has a PHWW hydraulic design of 1.5 MGD and a PIWW hydraulic design of 2.25 MGD. The combined peak hydraulics for the wastewater treatment system is 3.75 MGD. The total wastewater treatment system capacity exceeds the AWW/PHWW flow rate of 2.41 MGD for industrial wastewater inputs. The maximum well water (water supply) pumping rate for the malting facility is currently limited to 2.8 MGD. The process waste flow stream has two equalization basins. One is located in the malting complex and pumps process waste to the treatment system screenings/lift station. The other is located at the wastewater treatment system to feed the SBR. The malting complex equalization basin has a volume of 328,000 gallons. It currently has the overflow discharge to the city of Shakopee sanitary sewer system, which will be removed once the MBR expansion is completed. The SBR equalization basin has a volume of 362,000 gallons and feeds the SBR four times a day. The flow to the malting process is controlled by Rahr Malting s staff and the facility is staffed 24 hours per day, 365 days per year. Should there be a need to reduce the flow to the process wastewater treatment system due to major equipment failure to either process, the malting process volume would be lowered to the low volume steep flow rate of 1.18 MGD. It will take four hours for the transition from high volume to low volume flow rates. Since the MBR has duplicate processes, which can treat a flow rate up to 2.25 MGD, the only time there would be a need to change the malting process flow volume would be if the SBR process has 28

30 major equipment problems. Should this scenario happen, Rahr Malting will change all of the steeping flow volumes to the low flow/spray steep process. This scenario will require the storage of 27,000 gallons of excess flow above the maximum design capacity of the MBR process. Once the flow from the malting process has been reduced to the low volume steep flow rate, the excess wastewater from both equalization basins will be added to the treatment stream for processing through the MBR process treatment system. Maintenance staff is available 24 hours per day, seven days per week to make repairs as needed, and the volume of water treated is controlled by the water used during the malting process, which can be changed at any time should a reduction in flow to the wastewater treatment system be necessary. The MBR treatment system, in conjunction with currently available raw wastewater storage, has been designed to fulfill reliability requirements should the SBR need to be taken out of service on a short-term basis. The SBR has either standby equipment or a spare to be installed should the need arise. All process lift pumps are rated for 100 percent of the flow when there are two units, or two pumps can pump the flow rate with the largest unit out of service when there are three pumps. Proposed Wastewater Effluent Limitations The mass ammonia limits will remain the same after the proposed expansion as the mass ammonia limits required in the 1997 NPDES/SDS Permit. The TSS mass limits will remain the same after the proposed expansion as the mass ammonia limits required in the 1997 NPDES/SDS Permit. The monthly average phosphorus limit (2 mg/l) will be changed to a more stringent monthly average limit (1 mg/l) and the mass concentrations of phosphorus discharged to the Minnesota River will remain the same after the expansion as the mass concentrations required in the 1997 NPDES/SDS Permit. Limits for ph and dissolved oxygen will also remain the same after the expansion as the mass ph and dissolved oxygen limits required in the 1997 NPDES/SDS Permit. In order to achieve the mass limits, the wastewater treatment system will reduce effluent concentrations. The 1985/1987 low dissolved oxygen TMDL study for the reach of the Minnesota River from Jordan to its confluence with the Mississippi River is currently being updated. The update is expected to be completed in The discharge from the Rahr Malting is in this reach of the river; therefore the recommendations resulting from this update may impact the company s effluent limits in the future. 29

31 The current limits as well as the proposed limits are summarized in Table 5. Table 5 Proposed Water Quality Based Effluent Limitations Final Limits in Existing Permit Final Limits for Proposed Permit* mg/l Kg/day mg/l kg/day Substance or Characteristic AVG MAX AVG MAX AVG MAX AVG MAX CBOD Ammonia-N, May June July-September October November Min. DO, Apr.-Nov. (Flow at 6.0 Calendar Week Mean 6.0 Apr.- Weekl Mean Jordan < 20,000 cfs) Nov. y December-March (Flow at Jordan < 20,000 cfs) 7.0 Calendar Week Mean 7.0 Dec.- Mar. Weekl y Mean *These effluent limits may change when the Lower Minnesota River Modeling Project is complete 1 The current 1.5 MGD average daily flow was used for the mass load calculation. 2 The current 2.5 MGD maximum daily flow and 18 mg/l was used for this calculation. 3 The current CBOD 5 mass plus 62.8 lb/day (28.5 kg/day) of additional NPS CBOD 5 credits. Cal Mo Avg mg/l Phosphorus Management Plan (PMP) Cal Mo Cal Mo Avg Avg kg/day (kg/yr) mg/l 12 Mo Avg mg/l 12 Mo Avg mg/l Cal Mo Avg kg/day (kg/yr) Phosphorus, Total ,870 Receiving Waters Minn. R. ch classify the waters of the state. Class 2B waters are maintained to permit the propagation and maintenance of a healthy community of cool or warm water sport or commercial fish and associated aquatic life. These waters are sustainable for all kinds of aquatic recreation, including bathing. Class 2C waters permit the propagation and maintenance of a healthy community of indigenous fish and associated aquatic life. These waters are suitable for boating but generally are not considered suitable for bathing. Table 5 shows the classification of the Minnesota River below river mile The Fisheries and Wildlife Classification of the river changes from 2B to 2C at river mile Numeric water quality standards are an important part of the classification system. Point and NPSs are not allowed to cause a violation of the water quality standards. During the warm summer months, the Minnesota River below mile 22.0 historically did not meet the 5 mg/l dissolved oxygen standard. The primary reason is the large NPS loads entering the river upstream after mile

32 Classification Category Table 6 Minn. R. ch Minnesota River Classification System 1 River Classification by Mile 25 to to mouth Fisheries and Wildlife 2B 2C Industrial Consumption 3B 3B Aesthetic Enjoyment and Navigation 5 5 Other Uses Numeric water quality standards are an integral part of the classification system. The critical standard for the Minnesota River is 5 mg/l dissolved oxygen. The Rahr Malting wastewater treatment system does not discharge PCB or fecal coliform. The proposed wastewater treatment system expansion supplements Rahr Malting s existing SBR with an MBR system. The MBR system is characterized by low effluent turbidity (< 1 nephelometric turbidity units). Trading Agreement In the proposed draft NPDES/SDS Permit for the proposed wastewater treatment system expansion, Rahr Malting will be given credit for the NPS load reduction units that were achieved as a result of the 1997 trading agreement. The NPS load reduction units will offset the proposed increase in CBOD 5 of 28.5 kg/day for the proposed expansion and will not impact the requirements of the 1985 (amended 1987) Waste Load Allocation for the lower Minnesota River. The proposed draft NPDES/SDS Permit will not authorize Rahr Malting to obtain additional NPS load reduction units above lbs CBOD 5 per day. No additional NPS load reduction units will be credited to Rahr Malting should future trades, required for replacement purposes, exceed the current NPS load reduction units. Proposed Heat and Power Plant Koda Energy will discharge process wastewater to the Rahr Malting wastewater treatment facility for treatment. c. If wastes will be discharged into a publicly owned treatment facility, identify the facility, describe any pretreatment provisions and discuss the facility s ability to handle the volume and composition of wastes, identifying any improvements necessary. Sanitary wastewater generated at Rahr Malting is, and will continue to be, discharged into the city s sanitary sewer for treatment in the MCES Blue Lake Facility. Process wastewater currently discharged to the MCES Blue Lake Facility will be treated by the proposed wastewater treatment system expansion. Sanitary wastewater from Koda Energy will also be discharged to the MCES Blue Lake Facility. No other wastewater will be discharged into a publicly owned treatment facility. 31

33 d. If the project requires disposal of liquid animal manure, describe disposal technique and location and discuss capacity to handle the volume and composition of manure. Identify any improvements necessary. Describe any required setbacks for land disposal systems. The proposed project does not involve liquid animal manure. 19. Geologic hazards and soil conditions. a. Approximate depth (in feet) to Ground water: 19 minimum; 50 average. Bedrock: 5 minimum; 20 average. Describe any of the following geologic site hazards to ground water and also identify them on the site map: sinkholes, shallow limestone formations or karst conditions. Describe measures to avoid or minimize environmental problems due to any of these hazards. There are no sinkholes or abandoned wells on the site. The shallow limestone bedrock (Prairie du Chien Group) is close to the surface. Water was not encountered during soil borings to 18 feet. No hazard to ground water is believed to exist because of the bedrock formation and its proximity to the surface. The following information was taken from the Geologic Atlas for Scott County, prepared by the Minnesota Geologic Survey (2006). Scott County Atlas Series Map C-17, Plate 6 - Hydrogeology shows the water table configuration in surficial deposits. The Scott County Atlas also shows bedrock topography. The uppermost bedrock stratum under the site is the dolomitic limestone of the Prairie du Chien Group (Twin City Testing, Corp., 1991). This weathered limestone formation appears at an elevation of approximately 750 feet above sea level. Based on soil boring logs, the approximate depth to bedrock is 5 feet (minimum) and 6 feet (average). The approximate depth to ground water is conservatively estimated at 19 feet (minimum) and 50 feet (average). No free ground water was observed during subsurface exploration to 18 feet. b. Describe the soils on the site, giving SCS classifications, if known. Discuss soil granularity and potential for ground-water contamination from wastes or chemicals spread or spilled onto the soils. Discuss any mitigation measures to prevent such contamination. Based on soil type maps from the U.S. Department of Agriculture, Soil Conservation Service, there are two soil types underlying the proposed project site. HeB Sc Hubbard loamy fine sand, 2-6 percent slopes Stony land A soil boring investigation was performed on the proposed project site. Two test pits were dug. The following is a summary of the findings: Test Pit #1 0-3 feet below ground surface: Fill, lean clay and silty sand mixed, dark brown to black 3 5½ feet: Weathered limestone, tan 5½ feet: Relatively unweathered limestone, tan 32

34 Test Pit #2 0 2 feet below ground surface: Fill, silty sand, black 2 3 feet: Weathered limestone, tan 3 feet: Relatively unweathered limestone, tan The land has been altered since starting in 1936 and the slopes no longer are appropriate. In most areas the slope is less than two percent. Rahr Malting has a current Spill Prevention Control and Countermeasure (SPCC) Plan and SWPPP for its operations. Grain and malt are transported by rail car and the potential for spills of petroleum products is possible. Spill plans are designed to address this potential. Since occupying the site in 1936, the Rahr has not recorded any significant spills that would raise ground water concerns. The existing plans will be modified to account for the proposed heat and power plant. 20. Solid Wastes, Hazardous Wastes, Storage Tanks. a. Describe types, amounts and compositions of solid or hazardous wastes, including solid animal manure, sludge and ash, produced during construction and operation. Identify method and location of disposal. For projects generating municipal solid waste, indicate if there is a source separation plan; describe how the project will be modified for recycling. If hazardous waste is generated, indicate if there is a hazardous waste minimization plan and routine hazardous waste reduction assessments. Construction for the proposed wastewater treatment expansions may generate small amounts of construction debris. The construction contractor will be responsible for disposing of all construction debris. There is no animal manure produced at the site. Sludge generated in the wastewater process is not a biohazard because no sanitary sewage is processed in the facility. Currently, sludge is dewatered and land applied under SDS General Permit #MNG The Waste Water Treatment System will have the following process tanks: Pre-Expansion Post Expansion Chemical Tanks Quantity (each) Tanks Quantity (each) Ferric Chloride g g. Urea 2 3,000 g. 4 3,000 g. Citric Acid g. Slodium Hypochlorite ,000 g. Construction for the proposed heat and power plant may generate small amounts of construction debris. The construction contractor will be responsible for disposing of all construction debris. At full load, Koda Energy will generate approximately one truckload (20 tons) of ash daily. The nonhazardous ash is composed of 95 percent fly ash and 5 percent bottom ash. Ash from biomass combustion has qualities appropriate for land application. Koda Energy will explore beneficial uses for this ash. 33

35 b. Identify any toxic or hazardous materials to be used or present at the site and identify measures to be used to prevent them from contaminating ground water. If the use of toxic or hazardous materials will lead to a regulated waste, discharge or emission, discuss any alternatives considered to minimize or eliminate the waste, discharge, or emission. The wastewater treatment system requires the use of ferric chloride, urea, citric acid and chlorine (ten percent solution sodium hypochlorite). Ferric chloride and urea are used as nutrient in the wastewater treatment system. Citric acid and sodium hypochlorite are used for cleaning. These chemicals are stored in a secondary containment facility. Koda Energy will use up to 60 gallons per hour of Nitrogen oxidesout-a, a quality chemical reagent to reduce NO X air emissions. Koda Energy selected Nitrogen oxidesout-a because it is much safer and easier to handle than its alternative, ammonia. Nitrogen oxidesout-a is an aqueous solution of synthesized urea (49-50 percent) and water (49-50 percent). Potential acute effects include reddening, itching, and inflammation of the skin. The product is stable under normal ambient conditions of temperature and pressure. The material is not found to be toxic by oral exposure as defined by the Occupational Safety and Health Administration (OSHA). Based on the OSHA toxicity data for ammonium nitrate, the product is not expected to be toxic by dermal or inhalation. c. Indicate the number, location, size and use of any above or below-ground tanks to store petroleum products or other materials, except water. Describe any emergency response containment plans. The wastewater treatment system will not require above or below-ground storage tanks. The boiler building for the proposed combined heat and power plant will contain a 15,000-gallon urea tank to provide reagent to the SNCR system used to control NO X air emissions from the boiler. The urea tank will have its own room with containment provided. Tanker trucks will fill the tank from a fill station near the boiler building s southeast corner. Materials and equipment for containing spills will be located in the urea tank room and at the urea fill station. Trained personnel will promptly absorb small spills with a commercial or other absorbent and place it into a container for proper disposal. Personnel will use absorbent to dike larger spills and mop up or pump the spilled material into a container. No other above or belowground tanks are proposed to store petroleum products for the proposed Project. 21. Traffic. Parking spaces added: 0 Existing spaces (if project involves expansion): Estimated total average daily traffic generated: per day Estimated maximum peak hour traffic generated (if known) and its timing: Provide an estimate of the impact on traffic congestion affected roads and describe any traffic improvements necessary. If the project is within the Twin Cities Metropolitan area, discuss its impact on the regional transportation system. The proposed project will have temporary construction related impacts to area traffic in the area that will cease upon completion of construction. Delivery of materials and equipment will increase current truck traffic to the site by several trucks per day upon start of construction. These deliveries will quickly taper off and further deliveries will be intermittent and minimal. Traffic impacts from the construction workforce may increase by up to 25 vehicles per day. 34

36 Fuel delivery and ash removal trucks account for the primary traffic generated by the proposed project. Trucks delivering fuel enter the project site from West Third Avenue (south of the project), and travel 131 feet north and east to the receiving building. After unloading, the trucks travel 994 feet east and exit the project site on West Second Avenue. Vehicles travel an average of five miles per hour. Trucks removing ash enter the project site from the south on West Third Avenue. Trucks travel north and west 144 feet to the ash storage building. After loading, trucks travel 92 feet south and west to West Third Avenue and leave the project site. Trucks will enter Shakopee from the south after exiting off U.S. 169 to First Avenue (old Trunk Highway 169). From First Avenue, trucks will exit on to Apgar to West Third Avenue, enter the site and then exit onto either West Third or West Second Avenue, back to Apgar and then to First Avenue. The Minnesota Department of Transportation 2005 data reports 6,400 average annual daily traffic trips on First Avenue, 1,750 average annual daily trips on Apgar, and 1,200 average annual daily trips on West Third Ave. At full capacity, the proposed project will average 8 trucks per day (27.66 truck trips from Trunk Highway 169 through Shakopee and back to Trunk Highway 169). By using 50,000 tons per year of Rahr Malting byproducts, Koda Energy will reduce an average of 6.1 byproduct trucks per day (7.73 trucks or 12.2 truck trips). Koda Energy will add an average of 8 truck trips per day, increasing traffic on First Avenue by 0.43 percent and increasing traffic on West Third Avenue by 2.3 percent. Koda Energy will result in an annual total of 1,428 miles of truck traffic from fuel and ash trucks. 22. Vehicle-related Air Emissions. Estimate the effect of the project s traffic generation on air quality, including CO levels. Discuss the effect of traffic improvements or other mitigation measures on air quality impacts. Note: If the project involves 500 or more parking spaces, consult EAW Guidelines about whether a detailed air quality analysis is needed. The proposed wastewater treatment system expansion will have minimal traffic impacts. It will not add staff and deliveries, and shipments will not increase significantly. The combined heat and power plant will result in minor emissions from truck traffic and slight increases from additional staff. Emissions are due to the combustion of fuel and the emission of PM from contact with the road surfaces while traveling at the proposed project site and will be emitted in the following amounts annually: tons of Hydrocarbons tons of CO tons of NO X tons of CO 3.1 tons of PM 10 Currently, Rahr Malting emits 3.5 tons per year of PM 10 based on 1,927 miles per year. The project will include paving roadways that are currently unpaved, which will result in a reduction of 3.0 tons of PM 10 emissions from Rahr Malting. 35

37 23. Stationary Source Air Emissions. Describe the type, sources, quantities and compositions of any emissions from stationary sources of air emissions such as boilers, exhaust stacks or fugitive dust sources. Include any HAPs (consult EAW Guidelines for a listing), any greenhouse gases (such as carbon dioxide, methane, and nitrous oxides), and ozone-depleting chemicals (chlorofluorocarbons, hydrofluorocarbons, perfluorocarbons or sulfur hexafluoride). Also describe any proposed pollution prevention techniques and proposed air pollution control devices. Describe the impacts on air quality. Rahr Malting Process Related Air Emissions Rahr Malting generates air pollution from receiving, handling, storing, and processing barley. Various combustion sources throughout the facility heat glycol or provide direct heat for drying grain. The various sources at Rahr Malting emit PM, PM 10, SO 2, NO X, VOC, and CO. In 2003, actual air emissions from Rahr Malting were: Criteria Pollutant 2003 Emissions (tpy) Potential Emissions (tpy) PM, PM 10, SO 2, NO X, VOC 3 10 CO Production at Rahr Malting will not change as a result of either the proposed wastewater treatment system expansion or the proposed combined heat and power plant. Material receiving, handling, processing, and shipping produce most of the PM and PM 10 emissions at Rahr Malting, and these emissions will not change as a result of either project. Historically, malt operations dried malts in coal, oil, or peat-fired kilns. With the switch to cleaner fuels such as natural gas, malt facilities discovered that the sulfur in traditional fuels conditioned the malts, acted as a preservative, improved color, added flavor, and controlled N-nitrosodimethylamine through the reduction of ph in the malt. Modern malt facilities achieve the same effects by burning sulfur in the kilns to condition the malt. Sulfur burning produces most of the SO 2 from the facility. These emissions at Rahr Malting also will not change as a result of either expansion. Combustion emissions account for most of the NO X, VOC, and CO emitted by Rahr Malting. Koda Energy will produce steam for use at Rahr Malting. Purchasing steam from Koda Energy will reduce NO X VOC, and CO from Rahr Malting. Air Emissions Associated With Wastewater The Rahr Malting wastewater treatment system is an insignificant air emissions source. The proposed expansion is also an insignificant air emissions source. Because these kinds of facilities typically are insignificant emissions sources, the EPA has not developed emissions factors for small industrial wastewater treatment facilities. The MCES has evaluated potential human health risks from air emissions from its much larger treatment facilities. MCES calculations can help evaluate the potential for air emissions from the proposed Rahr Malting wastewater treatment system expansion. 36

38 MCES processes 251 million gallons/day. BOD is Total HAP emissions are approximately seven tons per year. Sulfates in influent lead to formation on hydrogen sulfide (H 2 S). H 2 S was the primary contributor to acute hazard index (HI) greater than one. The highest acute screening level HI associated with air emissions from MCES wastewater treatment was estimated to be four (later refinement reduced it to one). Chronic hazard indices were all estimated to be less than one. Receptors evaluated at the maximum HI location were workers within a few hundred feet from MCES sources. The nearest residential receptors (HI < 1) are about 0.8 miles from sources. H 2 S emissions were estimated based on testing conducted at the facility in the 1990s. Total facility maximum potential to emit emissions for H 2 S were estimated to be 0.2 g/s. These were primarily from the four liquid treatment processes that were predicted to contribute most to worker hazard: east primary clarifiers, gravity thickeners, east bar screen, and grit chamber biofilters. All were modeled as area sources. The clarifier was modeled with release height of zero meters, the screen and grit chamber modeled with release height of zero meters, and the thickener was modeled with release height of three meters. Using the MCES information as a guide, the potential air quality impacts from the wastewater treatment system at Rahr Malting were evaluated. Rahr Malting processes about 1.5 million gallons/day with a BOD of Assuming HAPs composition is similar to that of MCES, this would translate to approximately 300 lbs/year of HAPs from Rahr Malting (1 percent of MCES volumetric flow and twice the strength as indicated with BOD), or approximately 2 percent of MCES emissions. Assuming receptor distances are no closer than a few hundred feet and dispersion characteristics are no worse (the elevated sludge storage unit at Rahr Malting may be equivalent to the gravity thickener unit at MCES, which was also elevated), a simple approximation of the acute hazard quotient from the wastewater treatment at Rahr Malting would be 4 X 0.02, or This is likely conservative since the MCES acute hazard index of 4 was also contributed to by emissions units other than the H 2 S sources. All other MCES liquid source processing emissions resulted in hazard quotients and potential cancer risks less than one. Air Emissions from the Proposed Heat and Power Plant In Minnesota, air emission permits are required to operate certain existing facilities or to modify these regulated facilities. Depending on the facility, air emission permits may contain a wide range of federal and state requirements to minimize the impact of the air emissions from these facilities on the environment. The 1990 amendments to the Clean Air Act involved many significant changes to the federal air quality program, which, in turn, caused an overhaul of Minnesota's existing air permitting program. One of the larger changes was the addition of the Part 70 operating permitting program (or Part 70). Part 70 refers to the section of the Clean Air Act, where the requirements for this program can be found. Part 70 is found within Title 40 of the Code of Federal Regulations (CFR). Part 70 operating permits contain applicable conditions and requirements found in federal and Minnesota rules. A proposed project may initially be reviewed, in part, by examining potential air emissions, which are the air emissions expected when the equipment is operating 24 hours a day, 7 days a week, and 365 days a year without using control equipment and in the absence of any rule, or permit-based limitations. 37

39 Because the Koda Energy potential to emit for the regulated pollutants is over the federal Part 70 threshold, Koda Energy will be issued a Part 70 operating permit. For the proposed heat and power plant, the applicable provisions from the following rules will be contained in the Part 70 total facility operating permit: Federal New Source Review Prevention of Significant Deterioration (40 CFR 52.21); and, Federal Part 60 Subpart Db Standards of Performance for Industrial-Commercial-Institutional Steam Generating Units. Federal New Source Review PSD New Source Review (NSR) is a pre-construction review program. It consists of the PSD program and Non-Attainment Area program. Before a new facility is built, or prior to the expansion or modification of an existing facility, the emissions of regulated NSR pollutants resulting from the project must be analyzed to see if the project is subject to NSR. The EPA and the state of Minnesota have established NAAQS and MAAQS, which are not to be exceeded. These standards are designed to be protective of public health and the environment. As part of the air quality permit application, an air dispersion modeling assessment will be completed to determine compliance with the NAAQS and MAAQS. Air dispersion modeling is the primary predictive tool used by regulatory agencies for evaluating air impacts from facilities that are being modified. Air dispersion modeling uses comprehensive facility information (emission rate, stack height, stack diameter, and stack gas temperature and velocity), coupled with representative meteorological data (such as temperature, wind direction, and wind speed) to predict ambient air concentrations at and beyond the facility boundary. The NAAQS are human health-based or welfare-based standards that set the maximum concentrations that are allowed in the ambient air (i.e., the air that the general public is exposed to). These six pollutants are referred to as the criteria pollutants. These are the six criteria pollutants: NO X SO2, ozone/vocs PM 10 CO lead (Pb) The NAAQS are used with monitoring and modeling to determine if an area is in attainment or nonattainment with a particular NAAQS. More information on the NAAQS can be found in 40 CFR 50. The PSD program applies to facilities that are located in geographic areas that are deemed to be in NAAQS attainment or are unclassified. Attainment refers to the ambient (i.e., measured) air quality concentrations being lower than the PSD ambient standards for either NO X, PM 10, or sulfur oxides. The proposed heat and power plant location is currently deemed to be in attainment for all of the identified criteria pollutants. In order for a facility modification to be subject to PSD, the proposed pollutant s emission increase must exceed the PSD Significance Levels. In order to determine whether a proposed pollutant exceeds a PSD 38

40 Significance Level, the emission sources, the emission source s emission rates, and then the exceedance comparison are examined. Air emissions sources associated with the operation of the Koda Energy include: Truck Unloading Station (SV001) Rahr Byproduct Blow Lines (SV002) Fuel delivery and storage (SV 003 and 004) Fuel processing and transport (SV 005 and 006) Ground fuel transport (SV 007) Biomass-fired suspension boiler (SV 009) Ash storage and loadout (SV 8) Truck Traffic Table 8 summarizes criteria pollutant air emissions: Table 8: Koda Energy Pollutant Emissions from All Sources (tons per year) Activity PM PM 10 NO X CO SO X VOC Single HAP Total HAP SV001 Truck Unloading SV002 Blow Lines SV003 and 4, Fuel Transport SV005 and 6 Biomass Transport SV007 Ground Fuel Transport Boiler SV * * 22.5* Ash Handling SV Traffic Total * Will be restricted to these emission levels by permit restrictions. Grain receiving, storage and processing, ash handling, cooling towers, and truck traffic emit PM. These processes, with the exception of the cooling towers, are enclosed and are equipped with fabric filters to minimize particulate emissions. Section 6 of this EAW describes these processes in more detail. The air permit application provides a full discussion of these emissions sources and how the emissions were calculated. Table 9 summarizes the Koda Energy emission increases and the corresponding PSD Significance Levels. Table 9: Summary of Potential Emissions Attributable to the Proposed Heat and Power Plant Pollutant Potential Increase (ton/yr) PSD Significance Level (ton/yr) PM PM NO X (controlled) SO CO Ozone (as VOC) Lead

41 Koda Energy will be subject to a BACT determination for PM, PM10, NO X, and CO. BACT is determined by doing a top-down analysis of available pollution control technologies. Available technologies are ranked in descending order according to their control effectiveness. Many previous BACT determinations are kept in an EPA clearinghouse, which can be sorted by date and/or operation type. Based on the BACT determination, the NO X emissions will be subject to a BACT-determined control technology and emission limit. Review indicates that the boiler will be required to use low NO X burner, over-fire air boiler design, and SNCR as a BACT condition. SNCR entails the injection of ammonia, urea, and/or other nitrogen-bearing reagent with NO X present in the flue gas. Based on the BACT determination, the PM and PM 10 emissions will be subject to a BACT-determined control technology and emission limit. Preliminary review indicates that the boiler will be required to use mutlicyclones and an ESP as a BACT condition. Biomass handling stack vents as well as ash loadout stack vents will be required to use fabric filters. Based on the BACT determination, the CO emissions will be subject to a BACT-determined control technology and emission limit. Preliminary review indicates that the boiler will be required to apply good combustion practices as a BACT condition. For the PM 10, NO X, and CO emissions, the PSD analysis included an air quality analysis (i.e., dispersion modeling). An air dispersion modeling assessment was completed to determine compliance with the PM 10, NO X, and CO NAAQS, MAAQS, and applicable PSD increments. Air dispersion modeling is the primary predictive tool used by regulatory agencies for evaluating air impacts from facilities that are being modified. The air dispersion model used comprehensive facility information, coupled with representative meteorological data (such as temperature, wind direction, and wind speed) to predict ambient air concentrations at and beyond the facility boundary. The air modeling demonstrated that the proposed heat and power plant emissions will not exceed the PM 10, NO X, and CO NAAQS, MAAQS, and applicable PSD increments. The results of the federal PSD modeling were used to evaluate if the proposed BACT limits meet ambient standards and applicable PSD increments with some room for future growth. The model considered stack emission rates, location, temperature, velocity, and other dispersion-related items such as enhanced turbulence due to nearby buildings. The modeling also considered fugitive road dust and the future paving of existing unpaved roads at Rahr Malting and Koda Energy (i.e., approximately trucks per day) and idling diesel truck emissions nominally the equivalent of two idling diesel trucks for one-hour averages (i.e., diesel NO 2 exhaust for acute) and the equivalent of one idling diesel truck for annual averages (i.e., diesel PM exhaust for chronic). The number of idling trucks may be a somewhat conservative erring on the side of protecting public health and the environment for cumulative effects. The PSD review included modeling for PSD increments and NAAQS and MAAQS. The modeling demonstrated attainment of PSD increments and ambient standards for NO X and PM 10. CO is below federal significant impact levels full modeling is not required. 40

42 Modeling for toxic air pollutants demonstrated acceptable inhalation risks for the sum of Koda Energy and Rahr Malting without idling diesel truck emissions. Modeling for toxic air pollutants demonstrated elevated inhalation risks for the sum of all sources. The above elevated risks are primarily due to regional/ background conditions typical of suburban areas. Recent ( ) Twin Cities monitored background risk data indicates suburban risks including metals of 0.7 (acute), 1.0 (chronic non-cancer), and 4.0 (cancer). These were updated from the earlier Minnesota Statewide Air Toxics Monitoring Study ( ) report, which is available at html. A visibility analysis was performed for the nearest Class I Area (Rainbow Lake Wilderness Area). The screening procedure consisted of the methodology outlined in the EPA document Workbook for Estimating Visibility Impairment. The calculations were performed for various distances (starting at 250 kilometers - distance to Rainbow Lake) using the EPA VISCREEN model. The results indicate that there should be no visible plume impacts at the Rainbow Lake Wilderness Area resulting from the project. In addition, the permit will restrict SO 2 emissions from exceeding the PSD significant threshold. Federal Part 60 Subpart Db Standards of Performance New Source Performance Standards (NSPSs) are technology-based standards. Each NSPS applies only to source categories defined within the specific subparts of the NSPS regulations. The general provisions of the NSPS regulations are located in Subpart A of the rules (all NSPS regulations can be found in 40 CFR 60). It is possible that more than one NSPS regulation may apply to a facility. The proposed heat and power plant boiler is subject to the NSPS Subpart Db provisions (Standards of Performance for Industrial-Commercial-Institutional Steam Generating Units). This Subpart begins at 40 CFR 60.40b. For the proposed heat and power plant boiler, Subpart Db provides emission concentration limits for the following pollutants: PM Opacity In addition to the emission limits established by the NAAQS and MAAQS, Subpart Db has requirements that necessitate demonstration that the facility is meeting its emission limits for its regulated pollutants. However, these limits are technology-based limits rather than health-based limits. Also, the permit restricts the usage of natural gas to less than 10 percent of the annual combustion capacity. Due to this restriction, the boiler NO X emissions are not subject to Subpart Db. The boiler NO X emissions, however, remain subject to PSD review, as described above. Initial performance tests are required for PM and opacity. To ensure compliance with the requirements of the NSPS Subpart Db and permit emission limits, Koda Energy is installing multicyclones and ESP to control PM. This permit also restricts the facility from being designated as a major National Emission Standards for Hazardous Air Pollutants (NESHAP) source. The permit has limits for HAPs not to exceed 9.0 tons per year per any single pollutant and 22.5 tons per year for all HAPs combined. 41

43 Fuel Types The air quality permit authorizes the combustion of a biomass fuel blend of wood, by-products from Rahr, and oat hulls. In addition, the permit authorizes the facility to conduct trial test burns of additional biomass materials. Additional biomass fuels/blends may be allowed after evaluation and approval of the performance tests for the emissions listed in the biomass fuel testing requirements of the air quality permit. Koda Energy will be required to complete a Risk Assessment Screening Analysis for the additional fuels using emission factors developed during the required stack testing. These emission factors will also be used as input data in the MPCA's Risk Assessment Screening Spreadsheet (RASS). All of the remaining emission factors will be the same as those initially used. If the results of the RASS, or more refined model, for the additional biomass demonstrates that all of the risks are equal to or less than the risks calculated in the initial facility permitting RASS, Koda Energy may submit an application for the authorization to combust the additional fuels. This application will comply with the requirements of Minn. R through Minn. R , if a permit amendment is needed. If the results of the RASS, or more refined model, for the additional biomass demonstrates that any one of the risk(s) exceed the risk(s) calculated in the initial facility permitting RASS, Koda Energy shall submit the results of the RASS to the MPCA with the air quality permit application. Greenhouse Gas Emissions Gases that trap heat in the atmosphere and contribute to global warming are called greenhouse gases. Carbon dioxide, the primary greenhouse gas, is a product of combustion and is released into the atmosphere when anything is burned. When plants (biomass) grow, they absorb carbon dioxide from the atmosphere. When they are burned, that carbon dioxide is released. As new fuels are grown, they absorb an amount of carbon dioxide from the atmosphere roughly equal to the amount released when they are burned. Biomass fuels are assumed to not add carbon dioxide to the atmosphere because they continually recycle carbon dioxide as it is released into the atmosphere during combustion and reabsorbed back into the plants as new fuel is grown. Fossil fuels coal, oil, natural gas, gasoline are made from plant material deposited in the earth millions of years ago. When they burn, they release carbon dioxide stored when the earth was much warmer and the atmosphere contained more carbon dioxide. Combustion of fossil fuels causes carbon dioxide in the atmosphere to increase. By providing Rahr Malting with 120,000 lbs/ hour of steam, Koda Energy will directly replace 125 mmbtu/hr of natural gas per hour (127,500 standard cubic feet) or 1,117 million cubic feet per year of natural gas. This reduces emissions of the greenhouse gas carbon dioxide by over 67,000 tons per year (based on AP-42 Table 1.4-2). Indirectly, the Koda Energy will reduce carbon dioxide further. By replacing a coal-fired base load with Koda Energy s biomass to energy project, carbon dioxide emissions could reduce carbon dioxide by 190,000 tons per year (based on the percentage of Minnesota energy generated by coal, nuclear, and renewable sources in 2002). Comparing directly with coal, a 308-mmBtu/hr power plant firing Powder River Basin Coal will emit 394,936 tons of carbon dioxide annually. A 308-mmBtu/hr boiler firing biomass will emit 263,219 tons of carbon dioxide per year. When comparing actual carbon dioxide emissions, the Koda Energy boiler emits 42

44 nearly 132 thousand tons per year less than a comparable coal-fired plant. It is generally accepted that carbon dioxide from biomass combustion produces no net atmospheric carbon dioxide build-up because the growth of the biomass fuel withdraws from the atmosphere an amount of carbon dioxide equivalent to that released during combustion. Without the carbon dioxide emissions from biomass combustion, the coal-fired boiler annually produces 395 thousand tons more of the greenhouse gas carbon dioxide than the comparable biomass boiler. AERA The MPCA developed risk analysis tools in response to a growing demand from the public to know more about the quality of air. The AERA process provides for: (1) a streamlined review of facility air emissions; (2) a consistent format for presenting the quantitative risk estimates, along with qualitative information to provide context to these risk estimates; and (3) flexibility in the manner in which the quantitative risks are calculated (the input parameters may be more or less accurate so that the risk estimates may fall along a continuum between a more conservative upper bound assessment (screening) vs. a more accurate (refined) assessment of the risks). In the AERA guidance, the MPCA uses the term risk to refer to estimated additional lifetime cancer risks and potential noncancer health effects. Potential health effects from individual noncarcinogenic chemicals are expressed as a hazard quotient. Potential health effects from all noncarcinogens added together are expressed as a hazard index. Risk analyses assume that some level of risk is acceptable because no human activity is without risk. In general, the risk level deemed to be acceptable for emissions from a facility or an expansion project for the risks of all carcinogenic chemicals added together is less than 1 chance in 100,000 (10-5 ) of additional lifetime cancers based on the MPCA s interpretation of Minnesota Department of Health guidance. The level of risk deemed to be acceptable for all noncarcinogenic chemicals with the same target organ added together is a hazard index of 1.0. If a project shows a risk in excess of these levels, the MPCA examines the project analysis to determine whether future investigation or project modification is warranted. Interested readers can find more detailed information on the air risk analysis process at Koda Energy followed MPCA emission estimating guidance using existing wood combustion emissions factors. Koda Energy used either AP-42 factors or the 95 percent upper confidence limit calculated from the individual data points that make up the AP-42 factors for many pollutants. The 95 percent upper confidence level means emission factors were calculated for dioxins/furans and acrolein using emission factors from AP-42 and California s Air Toxics Emission Factors database. The emission factor data were based on wood combustion sources. Mercury was evaluated in two ways: (1) using AP-42 emission factors (1.79 lbs/year) and (2) using Maximum Achievable Control Technology NESHAP limit (approximately 8 lbs/year). MPCA staff believes these emission factors are reliable because the databases use data from actual testing of similar materials and similar types of equipment. The EPA and California emission factor databases have been routinely used by the MPCA staff on similar evaluations. Dispersion factors used conservative RASS values for lesser sources (e.g., fugitive dust sources) and refined AERMOD values for key sources (boilers, heaters, kilns), and supplemental Q/Chi approach (also referred to as Equivalent Risk Emission Rate, or ERER) for acute risks. The AERMOD modeling used meteorological data from the Minneapolis/St. Paul airport (surface data) and St. Cloud (upper air data). Risks were initially calculated used unpaired RASS values. The company has since updated acute risks using paired Q/Chi values and to estimate all risks assuming a taller boiler stack (220 feet). 43

45 Nearby residents were evaluated for potential risks from inhalation and vegetable consumption. Residential exposure was assumed to occur at the location of maximum annual concentrations related to the Koda boiler. This location is just northwest of the proposed boiler location near the highway. The location of maximum hourly concentrations is expected to be near the location of the maximum annual concentration. The area where the maximum concentration occurs is not zoned residential, but air concentrations in residentially zoned areas may not be significantly different since people live very near the facility. Acute and chronic non-cancer hazard indices associated with air emissions from the Rahr/Koda Energy facility were estimated to be less than the threshold considered acceptable. The threshold hazard index for noncarcinogens is one. Cancer risks were estimated for a hypothetical farmer at the location where maximum air concentrations in an area where farming could feasibly occur. This location is at a point bordering the north side of the 100-year floodplain, about a mile from the proposed project; the farmer cancer risk for this scenario is estimated to be 2 in 100,000 (2E-05), which is above the acceptable cancer risk threshold of 1 in 100,000 (1E-05). The estimated cancer risk represents the probability of an individual getting cancer due to exposure to the pollutants being assessed. However, sustenance farming is not expected to occur in this area. The sustenance farmer is assumed to have a regular diet of farm-generated meats, eggs, produce, and dairy products. A land use evaluation suggests that sustenance farming does not occur at the location assessed, and development plans suggest it will not occur in the reasonably foreseeable future. Further, a risk isopleth corresponding to a cancer risk of 1E-05 was placed around the facility for the purpose of scanning for potential farming in the zone that could potentially exceed the acceptable cancer risk threshold. This area ranges from about one-halfmile west and east of the facility to about 1 to 1.5 miles north and south of the facility. Only small portions of the area appear to be open fields used for crop growth. Livestock growth is not evident. Inspection of aerial photographs and interviews with county and extension representatives suggest that little to no livestock production is undertaken in that area. A second region was considered for potential sustenance farming. This area is bounded by a risk isopleth corresponding to a cancer risk of 0.4 in 100,000 (4E-06 - approximately 40 percent of the acceptable risk threshold). This is a very large area and would take a significant amount of time to visually survey; however, the area lies within the city limits of Chaska and Chanhassen and there are no plans for agricultural activities in the 2020 comprehensive plans for those cities. City ordinances in effect in some of these areas indicate that the area bounded by a 4E-06 farmer cancer risk lies either on the 100-year floodplain or in the city limits of Chanhassen, Chaska, Eden Prairie, or Shakopee. The city planning department in Chaska was contacted and they have a city ordinance that bans cattle or livestock within the city limits unless it is zoned agriculture. Looking at the current zoning map for Chaska, there is no land zoned agriculture within the city limits. Similar information has not yet been reviewed for the other cities in the vicinity. Risks related to air emissions from the Rahr Malting wastewater treatment system were not quantitatively evaluated. A qualitative analysis based on a process volume comparison with MCES, for which a full risk assessment from air emissions was conducted. The analysis included a comparison of source unit types, liquid volumes and liquid strengths processed, dispersion characteristics, and receptor locations relative to sources. Rahr Malting wastewater treatment system emissions are expected to be approximately 44

46 two percent of MCES emissions, which would result in no more than an acute hazard index of Chronic hazard indices and cancer risks from MCES were less than thresholds; Rahr Malting wastewater treatment system risks would be proportionately lower than thresholds. The AERA assumed that the Koda Energy boiler will be operating at 8,600 hours per year. The proposed heat and power plant boiler will operate, at a minimum, of 51 weeks per year, at 60 percent of its design availability. Depending on electricity prices, the boiler may operate up to 100 percent of its design availability. It was assumed that the boiler will be operating 24 hours per day. Emissions from the proposed heat and power plant boiler are based on 100 percent capacity. While the proposed heat and power plant boiler is under normal operation, the Rahr Malting glycol heaters (natural gas) will not be in operation. When the Koda Energy proposed heat and power plant boiler is either in shutdown or startup mode, the Rahr Malting glycol heaters will be staging up or down in operation. Because Rahr Malting can only use a fixed amount of steam, the proposed heat and power plant boiler and Rahr Malting glycol heaters operation will be staged so as to not produce excess steam. It is anticipated that Koda Energy shutdown and startup will be on natural gas. Hence, the assumption of basing the emissions from 100 percent proposed heat and power plant boiler capacity is representative for the overlap of startup and shutdowns. It is estimated that the emissions used are generally conservative. Many of the emission factors were based on AP-42 wood factors. California and EPA Boiler NESHAP suggest AP-42 values should be conservative for biomass fuels other than wood. In addition, the proposed heat and power plant boiler is being specifically designed for biomass combustion. The proposed heat and power plant boiler should have lower actual emissions than some of the older boilers in the AP-42 database. In addition, 95 percent Upper Confidence Level emissions were used for a number of emission estimates. Wood emission factors from AP-42 and California s Air Toxics Emissions Factors database were used to estimate dioxin/furan emissions, and AP-42 wood emission factors were used to estimate mercury emissions. Some factors could result in an over-prediction of risk and others could result in under-prediction. Mercury speciation assumes 30 percent of mercury emissions are divalent, which would, in large part, deposit near the facility. This may be conservative, but data are not yet available to substantiate that claim. On-site idling vehicle analysis was performed for the cumulative effects analysis. The quantitative risk analysis only evaluated acute NO X and non-cancer chronic effects from diesel exhaust. It is commonly understood that diesel exhaust is carcinogenic; however, there is not yet consensus on which unit risk value to use for risk assessment from the range of values available. Idling vehicle emissions have not historically been included in AERAs. Adding the vehicle-related hazard quotients to the acute and chronic hazard indices would increase the site-related HIs from 0.3 (both acute and chronic) to 0.4. The maximum annual concentrations are predicted to fall just north of the facility near the south side of the highway. The location of the maximum acute modeled concentrations is not reported; however, it is anticipated that it will fall inside the property boundaries and near the location of the maximum predicted annual concentrations. 45

47 The emergency generator emissions are not included in the quantitative analysis. Since the company only operates the engine four times a year for testing purposes, this will not impact the chronic results. Given that the nearest residence is only about 150 meters and the stack height is about 47 feet, under calm atmospheric conditions hourly NO X emissions are not well-dispersed. This could result in acute hazard indices higher than those in the analysis. Dioxins/furans are known to have non-cancer effects, yet health benchmarks are not yet available with which to assess these endpoints. This will result in an under-prediction of non-cancer risks. However, because there does not appear to be significant opportunity for dioxin/furan accumulation in all the foods assumed in the farmer ingestion scenario (beef, pigs, chickens, eggs, milk) it is unlikely that dioxins/furans related to the project will accumulate enough to result in a significant incremental increase to background levels already in food products obtained from various sources. The MPCA staff finds that the potential increase in air emissions from the proposed project and Rahr Malting are unlikely to exceed ambient air quality standards for criteria pollutants, including emissions from existing projects. For air toxics, the risk analysis indicates that the cumulative impacts from the proposed project and Rahr Malting with emissions from other existing projects would not have the potential to be significant. 24. Odors, noise and dust. Will the project generate odors, noise or dust during construction or during operation? Yes No If yes, describe sources, characteristics, duration, quantities or intensity and any proposed measures to mitigate adverse impacts. Also identify locations of nearby sensitive receptors and estimate impacts on them. Discuss potential impacts on human health or quality of life. (Note: fugitive dust generated by operations may be discussed at item 23 instead of here.) Construction Noise During construction, there will be noise from the trucks and earthmoving equipment. In addition, the OSHA requires vehicle back up alarms on vehicles that have an obstructed rear view. An estimated sound level for the backup alarm is approximately 97 decibels, as a time weighted average (dba). Construction will also involve welding, grinding, cutting, drilling, hammering, heavy equipment operation, and other activities that generate noise. The city of Shakopee has zoned the area immediately adjacent to the project as either heavy or light industrial. Residential areas to the south of the proposed project site may observe elevated noise levels during construction. With the exception of a handful of residential properties, large buildings and trees buffer most residential properties potentially impacted by noise from the project. To minimize impacts on nearby residences, construction will take place during daylight hours and should not have impacts on human health or the quality of life. Construction noise is unavoidable, but the effects of excessive sound levels can be minimized by acting to limit noise intensity. The specific actions include the following: Require contractors to comply with Minnesota Noise Rules for vehicles. Minn. Stat states limits for motor vehicles with a manufacturer s gross vehicle weight rating of more than 10,000 pounds. Require contractors to have truck mufflers working properly. Limit construction activities to hours allowed by city ordinances. 46

48 Potential Operations Noise The proposed heat and power plant will be located on property leased from Rahr Malting. Per Minn. R , subp. 2, the sound levels in the residential areas produced by the proposed project must not exceed an L50 of 50 dba and an L10 of 55 dba during the hours of 10:00 p.m. to 7:00 a.m. The proposed heat and power plant includes indoor and outdoor equipment that have sound levels. The indoor equipment will have attenuation provided by the building, but the attenuation will be reduced in the summer time when louvers, doors, or windows are opened for ventilation. The three significant noise sources that are not housed in buildings include the ID fan, glycol fans, and the ash handling blowers. Each of these outdoor sources must not exceed a sound pressure level of 95 dba at a distance of 3 feet for the L50 sound levels to be at 50 dba or less at the residential area 582 feet from the proposed heat and power plant. Based on data provided by the design engineers or measurements from the sound monitoring analysis, this equipment will meet this requirement. An extensive sound monitoring analysis determined L50 sound levels from the Rahr Malting facility to be approximately 54 dba at a residential area 582 feet from the stack of the new project and 56 dba at a residential area 756 feet away from the stack of the new project. These L50 sound levels exceed the state standard of 50 dba. The sound monitoring analysis concluded there are multiple noise sources at the existing facility. There has not been any success in identifying a major source (or sources) that can be modified to reduce the overall impact on the neighbors. Rahr Malting will continue to explore ways to decrease noise from their facility. If the project produces an L50 sound level of 50 dba at these two residential areas, the sound levels should increase to 55 dba and 57 dba, respectively. Potential Odors While people often associate odors with the burning of biomass wood, grass, leaves, etc. a modern industrial boiler is a controlled combustion unit designed for efficient combustion. Temperatures achieved in industrial boilers generally destroy the organic compounds that typically cause the odors associated with uncontrolled biomass burning. Storage of moist biomass can cause odors as a result of fermentation and decomposition. The proposed heat and power plant fuels will typically have less than 10 percent moisture and a high turnover (less than fours days of storage are available), which will mitigate the potential for odor from stored fuels. Odor potential from the operation of the wastewater treatment system is reduced by enclosing treatment facilities. 25. Nearby resources. Are any of the following resources on or in proximity to the site? a. Archaeological, historical, or architectural resources? Yes No b. Prime or unique farmlands or land within an agricultural preserve? Yes No c. Designated parks, recreation areas, or trails? Yes No d. Scenic views and vistas? Yes No e. Other unique resources? Yes No If yes, describe the resource and identify any project-related impacts on the resources. Describe any measures to minimize or avoid adverse impacts. The Minnesota Historical Society identified archaeological and historical sites in the area of these proposed projects but none on the project site. These include several houses, commercial buildings and 47

49 church buildings located in downtown Shakopee near the project site. Air dispersion modeling, discussed in Section 11 of this EAW shows that air quality around these resources will be protected and discusses impacts to scenic views and vistas, parks, and other unique resources. The Air Modeling Impact Assessment and the AERA have identified sensitive receptors (see Exhibit 9) within one mile of Koda Energy. They include Riverview Park, Lyons Park, Riverside Park, Holmes Park, Hiawatha Park, St. Mark Church, St. Mary School, Sweeny Elementary School, Shakopee School District Central Family Center, Shakopee High School, and the Friendship Manor Nursing Home. The Air Modeling Impact Assessment and the AERA show that impacts on these receptors are within acceptable levels. 26. Visual impacts. Will the project create adverse visual impacts during construction or operation? Such as glare from intense lights, lights visible in wilderness areas and large visible plumes from cooling towers or exhaust stacks? Yes No If yes, explain. No adverse visual impacts are anticipated. New structures from the two projects will be smaller than adjacent buildings. The proposed heat and power plant will exhaust from a 220-foot stack. Water vapor from this stack may be visible from varying distances depending upon weather and temperatures. The plume from this stack will be similar in size and intensity to other plumes currently visible from Rahr Malting. Under normal operating conditions, when Koda Energy is operating, existing combustion emissions sources from Rahr Malting will not be operating. Lighting will be similar in intensity and scope with existing lighting at the 18-acre Rahr Malting site. A visibility analysis conducted for the proposed heat and power plant shows it will have minimal visibility impacts on the Minnesota Valley Wildlife Refuge. The Minnesota River Valley is lower than the surroundings. Existing buildings at the Rahr are 120 feet higher than the tallest buildings at the proposed heat and power plant site and will shield the proposed heat and power plant from the Minnesota Valley National Wildlife Refuge. 27. Compatibility with plans and land use regulations. Is the project subject to an adopted local comprehensive plan, land use plan or regulation, or other applicable land use, water, or resource management plan of a local, regional, state or federal agency? Yes No If yes, describe the plan, discuss its compatibility with the project and explain how any conflicts will be resolved. If no, explain. The proposed use for the project site is consistent with historic use of the land on which it will be built. Existing local plans, land use regulations, and resource management plans do not call for changes to the historic and proposed land use for the project site. The city of Shakopee has zoned the proposed project site as heavy industrial. The land immediately to the south of the proposed project site is classified as light industrial. Major regional planning issues for the Shakopee area involve projected increases in residential development and associated stresses to regional water, wastewater, and transportation resources. With the exception of domestic sanitation requirements for the workforce (three to five on-site employees per shift), the project will not require additional regional water or wastewater resources. 48

50 Rahr Malting currently averages 32 trucks per day - 22 raw materials delivery trucks, 4 malt shipping trucks, and 6 byproducts shipping trucks. The project will require 13 fuel delivery trucks and 1 ash removal truck per day and will eliminate 6 daily byproducts shipments from Rahr Malting. The project will increase truck traffic by 25 percent (8 trucks per day), which is well within the scope of local and regional transportation plans. The city of Shakopee s 2020 Comprehensive Plan identifies its future development goals and objectives. The last update of the Comprehensive Plan that received Metropolitan Council acceptance was completed in 1999, and it looked ahead to the year In the Shakopee 2020 Comprehensive Plan, the city has designated the project area as industrial. The proposed wastewater treatment expansion and the proposed heat and power plant are consistent with the City of Shakopee 2020 Comprehensive Plan. In 2006, the city of Shakopee began this update of the Comprehensive Plan and has targeted fall 2007 for its completion. The Scott County 2020 Comprehensive Plan Update, published May 23, 2001, designates the proposed project areas as an existing commercial/industrial area. The plan states that, these areas will be allowed to accommodate additional development provided necessary infrastructure is provided. The Rahr proposed wastewater treatment expansion and the proposed heat and power plant are consistent with the Scott County 2020 Comprehensive Plan Update. 28. Impact on infrastructure and public services. Will new or expanded utilities, roads, other infrastructure or public services be required to serve the project? Yes No If yes, describe the new or additional infrastructure or services needed. (Note: any infrastructure that is a connected action with respect to the project must be assessed in the EAW; see EAW Guidelines for details.) Additional infrastructure, including expanded utilities or roads, will be required to serve the proposed project. 29. Cumulative impacts. Minn. R , subp. 7, item B requires that the RGU consider the cumulative potential effects of related or anticipated future projects when determining the need for an environmental impact statement. Identify any past, present or reasonably foreseeable future projects that may interact with the project described in this EAW in such a way as to cause cumulative impacts. Describe the nature of the cumulative impacts and summarize any other available information relevant to determining whether there is potential for significant environmental effects due to cumulative impacts (or discuss each cumulative impact under appropriate item(s) elsewhere on this form). Cumulative potential effects are environmental effects that result from the proposed project in conjunction with other projects in a given area. The effects from any one project may be small; however, the aggregated effects from all the projects together may be significant. Water Quality Wastewater Discharge The proposed wastewater treatment system expansion is designed to meet the needs for the maximum capacity of Rahr Malting and Koda Energy. There are no future plans for expansion on the existing 18-acre Rahr Malting property in Shakopee. The Rahr Malting wastewater treatment system discharges at mile 25.3 on the 335-mile long Minnesota River. The Minnesota River is impaired by both point sources and nonpoint sources of pollution. More 49

51 than 150 wastewater treatment facilities discharge to the approximately 16,770 square miles that the Minnesota River Basin covers, including 13 major watersheds in Minnesota. The Minnesota River from River Mile 44.2 to the river mouth conforms with the study area used for the Lower Minnesota River Model, which extends from River Mile 44.2 to the confluence of the Minnesota and Mississippi rivers. Sixteen facilities discharge to the Lower Minnesota River between Carver Creek and the river mouth, including the Jordan Wastewater Treatment Facility, MA Gedney, Black Dog Generating Plant cooling water, and the Seneca Wastewater Treatment Plant. The Clean Water Act requires states to publish an updated list of streams and lakes that fail to meet their designated uses because of excess pollutants. The Lower Minnesota River Dissolved Oxygen TMDL identifies allowable levels of phosphorus that will result in the attainment of the dissolved oxygen standard in the Minnesota River s final 22 miles. To implement this TMDL, the MPCA issued an NPDES/SDS Minnesota River Basin General Phosphorus Permit Phase I. This permit regulates phosphorus discharge from facilities that contribute phosphorus to the lower Minnesota River during low flows. The permit identifies 40 point sources that discharge phosphorus to the Minnesota River and requires them to meet a five-month mass phosphorus limit. The Minnesota River Basin General Phosphorus Permit requires the Rahr Malting wastewater treatment system and other listed facilities with continuous discharges greater than 1,800 lbs/year to comply with the conditions of its existing NPDES/SDS Permit. Therefore, to further reduce the loadings to the lower Minnesota River, the MPCA proposed to target a 40 percent reduction in NPSs in the watershed. With the NPS load reduction units previously obtained by Rahr Malting, it is believed that the proposed effluent limits in the proposed draft NPDES/SDS Permit will not impact the requirements included in the current TMDL. The Rahr Malting wastewater treatment system does not discharge PCBs or fecal coliform. The wastewater treatment system expansion supplements the existing SBR with a MBR. The MBR system is characterized by low effluent turbidity (< 1 nephelometric turbidity units). Stormwater The majority of stormwater runoff from the proposed heat and power plant location currently discharges to a city of Shakopee storm sewer and then to the Minnesota River. The Minnesota General Stormwater Permit requires Rahr Malting to prepare and implement an SWPPP and to prepare and submit annual reports. The plan is complete and all measures are implemented. The plan covers the existing wastewater treatment system and measures in the plan are appropriate for the proposed wastewater treatment system expansion. The Rahr Malting SWPPP also covers the proposed heat and power plant location. The Rahr Malting SWPPP focuses on control the potential for stormwater pollution as a result of grain loading and unloading operations. High pollution potential areas identified in the Rahr Malting SWPPP include receiving areas, loadout areas, transfer points and air emissions points. Identified sources of pollution include spillage from trucks, rail cars and loading equipment. Activities at Koda Energy that may 50

52 contaminate stormwater are consistent with those described in the Rahr Malting SWPPP and the measures in the Rahr Malting SWPPP are appropriate measures for controlling these potential stormwater contaminant sources. There is no new water appropriation requested or required for this project. Air Quality Cumulative potential effects to air quality that may result from the proposed heat and power plant have been evaluated using dispersion modeling tools that consider potential emissions from the proposed heat and power plant and Rahr Malting, other specific projects in the area (for criteria pollutants), as well as regional/background sources. Potential human health effects from the proposed heat and power plant and Rahr Malting were evaluated using the AERA process. (See Section 23 for a detailed discussion of these analyses and applicable regulatory emission limitations.) For cumulative impacts from criteria pollutants, the dispersion modeling for the proposed project and other projects in the area demonstrates full compliance with NAAQS and MAAQS. For air toxics, the analysis is based on emissions from the proposed project and Rahr Malting and the regional/background source contribution derived from monitored ambient concentrations of air toxics collected as part of a study to establish baseline ambient air toxics concentration data for various locations throughout the state. This study characterizes ambient air concentrations of specific air toxics in rural, urban, and suburban locations in Minnesota. This study was not designed to provide specific information on the cumulative impact of air toxics in a specific geographical area. However, it provides information that can be used at a screening level for use in evaluating cumulative impacts. Ambient air toxics are comprised of three primary components: point sources, area sources and mobile sources. Point sources are typically large stationary sources (e.g., power plants, refineries, and this proposed project). Area sources are also often stationary, but are generally smaller sources of emissions, such as dry cleaners, gasoline service stations, residential furnaces, and fireplaces. Mobile sources include cars and trucks used on the road and non-road sources, such as lawn and garden equipment, recreational equipment (e.g., boats and ATVs), construction equipment, aircraft, and locomotives. On average across the state, 57 percent of the air toxic emissions are from mobile sources, 30 percent are from area sources, and 13 percent are from point sources. The maximum noncancer risk attributed to the proposed heat and power plant and Rahr Malting is 0.3. With the addition of emissions from on-site idling trucks and the regional/ background source contribution, the total is around one for acute and chronic noncancer exposure. The potential increase in air emissions from the proposed project are unlikely to exceed any air quality standard and the contribution from the proposed project, along with other nearby sources, are around a hazard index of 1.0; thus, MPCA staff has no available information to indicate that the noncancer impacts from the proposed project have the potential to be significant. The maximum cancer risk due to emissions from the proposed heat and power plant and Rahr Malting is about 0.4 E-05. When added to a representative ambient monitored regional/background suburban cancer risk, the total cancer risk is about 4.3E-05. Based on the contribution that the proposed project will add to the point source component of the total cancer risk, the MPCA risk managers have no information indicating that the cancer impacts from the projects in the area have the potential to be significant. 51

53 Evaluation of the environmental effects from mobile sources is an emerging issue that the MPCA, the EPA, and regional organizations are in the process of evaluating. Controlling emissions from mobile sources is a national issue as vehicles may travel across state lines and the concentration at any specific location at a given time is variable. It is appropriate to consider emissions in the context of federal regulations that would impact the source of emissions, rather than attempting to identify local methods of control. According to the Assessment and Standards Division Office of Transportation and Air Quality EPA 2006 publication: Draft Regulatory Impact Analysis: Control of Hazardous Air Pollutants from Mobile Sources: EPA is proposing new standards to reduce emissions of Mobile Source Air Toxics including benzene and overall hydrocarbons from motor vehicles, motor vehicle fuels, and portable gasoline containers (gas cans). This Regulatory Impact Analysis provides technical, economic, and environmental analyses of the proposed new emission standards. The anticipated emission reductions will significantly reduce exposure to harmful pollutants and also provide assistance to states and regions facing ozone and particulate air quality problems that are causing a range of adverse health effects, especially in terms of respiratory impairment and related illnesses. The MPCA staff finds that the potential increase in air emissions from the proposed heat and power plant and Rahr Malting are unlikely to exceed ambient air quality standard for criteria pollutants, including emissions from existing projects. For air toxics, the risk analysis indicates that the cumulative impacts from the proposed heat and power plant and Rahr Malting with emissions from other existing projects would not have the potential to be significant. Wildlife The proposed project will not degradate or fragment existing wildlife habitat. The proposed heat and power plant location is used as haul roads, parking, storage, and other industrial used. The soils consist of high amounts of fill and are compacted from truck traffic. The site provides very little habitat. Rahr Malting is a food processing facility and wildlife on the property is discouraged to avoid contamination of raw materials and products. To discourage wildlife, spills are promptly cleaned up. No wetlands exist on the proposed project site. Traffic Traffic impacts are discussed in items 21 and 22. Review of Minnesota Department of Transportation traffic maps and discussions with city of Shakopee and Scott County economic development staff did not indicate any significant traffic impacts. 30. Other Potential Environmental Impacts. If the project may cause any adverse environmental impacts not addressed by items 1 to 28, identify and discuss them here, along with any proposed mitigation. There are no other adverse environmental impacts that have not been previously identified. 52

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55 Exhibit 1 COUNTY MAP WITH GENERAL LOCATION OF PROJECT Project Location

56 Exhibit 2 UNITED STATE GEOLOGICAL SURVEY 7.5 MINUTE, 1:24,000 SCALE MAP WITH PROJECT LOCATION Project Location

57 EXHIBIT 3 PROPOSED HEAT AND POWER PLANT PROPOSED WASTEWATER TREATMENT SYSTEM EXPANSION NORTH EXISTING WASTEWATER TREATMENT SYSTEM

58 Exhibit 4

59 Exhibit 5

60 Exhibit 5

61 Original Message From: Cinadr, Thomas To: Sent: 5/17/2007 8:15:51 AM Subject: RE: Database Search for EAW Request Exhibit 6 THIS IS NOT A PROJECT CLEARANCE. This message simply reports the results of the cultural resources database search you requested. The database search produced results for only previously known archaeological sites and historic properties. Please read the note below carefully. For further information contact Kelly Gragg-Johnson by phone at or at kelly.gragg-johnson@mnhs.org. Archaeological sites and historic properties were identified in a search of the Minnesota Archaeological Inventory and Historic Structures Inventory for the search area requested. Reports containing the results of the search are attached. The result of this database search provides a listing of recorded archaeological sites and historic architectural properties that are included in the current SHPO databases. Because the majority of archaeological sites in the state and many historic architectural properties have not been recorded, important sites or structures may exist within the search area and may be affected by development projects within that area. Additional research, including field survey, may be necessary to adequately assess the area s potential to contain historic properties. With regard to s (EAW), a negative known site/structure response from the SHPO databases is not necessarily appropriate information on which to base a "No" response to EAW Question 25a. It is the Responsible Governmental Unit s (RGU) obligation to verify the accuracy of the information contained within the EAW. A "No" response to Question 25a without written justification should be carefully considered. If you require a comprehensive assessment of a project s potential to impact archaeological sites or historic architectural properties, you may need to hire a qualified archaeologist and/or historian. Please contact the SHPO by phone at or by at mnshpo@mnhs.org for current lists of professional consultants in these fields. The Minnesota SHPO Survey Manuals and Database Metadata can be found at Tom Cinadr Survey and Information Management Coordinator Minnesota State Historic Preservation Office Minnesota Historical Society 345 Kellogg Blvd. West St. Paul, MN (voice) (fax)

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63

64 Exhibit 8

65 Exhibit 9