August 28, 2019

FINDING OF NO SIGNIFICANT IMPACT

TO ALL INTERESTED GOVERNMENTAL AGENCIES AND PUBLIC GROUPS

As required by state and federal rules for determining whether an Environmental Impact Statement is necessary, an environmental review has been performed on the proposed action below:

Project Location Project Number Total Cost

Town of Ryegate, Wastewater System Improvements Project Ryegate, Montana C304245 $1,958,000

The Town of Ryegate, through its 2016 Preliminary Engineering Report (PER), identified the need to make improvements to the Town wastewater treatment lagoons. The existing lagoons are approximately 40-years old, are leaking and have deteriorated to the point where they no longer function as designed. Leaking effluent from the lagoons places several area wells at risk of receiving groundwater contaminated with poorly treated wastewater.

The Town has determined a preferred alternative would be to construct a lined lagoon system that allows for full evaporation of effluent most years. The MPDES discharge permit will be retained so if the ponds become full, periodic discharge to the existing outfall can be accomplished.

The proposed project consists of approximately 1.4 acres of primary treatment pond and 6.6 acres of storage/evaporation pond. The single lift station operated by the Town will also undergo repairs within the scope of this project.

The estimated project cost (including administration, engineering, and construction) is $1,958,000. The Town will fund this work with grants from the DNRC RRGL program ($125,000), and the USDA RD program ($1,100,000). The town will contribute $68,000 and borrow the balance ($665,000) from the USDA RD loan for the work. The DEQ Water Pollution Control State Revolving Fund (SRF) program will provide interim financing via a short-term loan to get the project constructed . Those loan funds will be paid off with the USRD project funding once the project is substantially complete.

Federal and State grant/loan programs will fund the project. Environmentally sensitive characteristics such as wetlands, floodplains, threatened or endangered species, and historical sites are not expected to be adversely impacted because of the proposed project. Public participation during the planning process demonstrated support for the selected alternative. No significant long-term environmental impacts were identified. An environmental assessment (EA), which describes the project and analyzes the impacts in more detail, is available for public scrutiny on the DEQ web site http://deq .mt.gov/Public/ea and at the following locations:

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Department of Environmental Quality 1520 East Sixth Avenue P.O. Box 200901 Helena, MT 59620-0901 tcampbell@mt.gov

Town of Ryegate P.O. Box 163 Ryegate, MT 59074

Comments on the EA may be submitted to the Department of Environmental Quality at the above address. After evaluating comments received, the department will revise the environmental assessment or determine if an environmental impact statement is necessary. If no substantive comments are received during the comment period, or if substantive comments are received and evaluated and the environmental impacts are still determined to be non­significant, the agency will make a final decision. No administrative action will be taken on the project for at least 30 calendar days after release of the Finding of No Significant Impact.

Sincerely,

~~ Engineering Bureau Water Quality Division Montana Department of Environmental Quality

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I. COVER SHEET

TOWN OF RYEGATE WASTEWATER IMPROVEMENTS PROJECT

ENVIRONMENTAL ASSESSMENT

A. PROJECT IDENTIFICATION

Applicant: Address:

Project Number:

B. CONTACT PERSON

Name: Address:

Telephone:

C. ABSTRACT

Ryegate, Town of P.O. Box 163 Ryegate, MT 5907 4

DEQ, WPCSRF Project# C304245

Patti Bruner, Mayor P.O. Box 163 Ryegate, MT 59074

(406) 568-2320

The Town of Ryegate, through its Wastewater System Improvements Preliminary Engineering Report (PER), written in May of 2016, identified the need to make improvements to its wastewater system. The original wastewater collection and treatment system for the Town of Ryegate was constructed to replace cesspools, pit privies and septic systems. The collection system and lagoons serve the residents of Ryegate with a current population of 243. The facility is a two-cell facultative lagoon with a total surface area of 4. 7 acres. It was originally designed for a flow of 50,000 gallons per day for a design population of 500 people. The town has maintained a discharge permit (MPDES #MT0020451) but has reported no discharge since issued in 1975.

The collection system includes a single lift station for the south part of town, with the remainder being gravity flow to the lagoons. Based on the results of the 2012 lagoon leakage study, the wastewater lagoons are leaking at a rate in excess of DEQ-2 design standards for allowable leakage and are placing several downgradient drinking water wells at risk.

The Preliminary Engineering Report (PER) describes existing conditions, needs, alternatives evaluated, and the preferred alternative to remove accumulated solids and meet design standards. The town proposes to construct a total retention lagoon based system where all wastewater will evaporate in lieu of discharge. The total retention system will be a two-cell system designed to meet anticipated growth and permit conditions for a 20-year planning period.

The PER and Uniform Funding Application prepared by the town establish a project cost of approximately $1,958,000 which includes all engineering, legal, administrative and construction costs. The town applied for and has received grants from the DNRC RRGL program for $125,000 and from USDA Rural Development for $1,100,000. The town

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II.

proposes to contribute $68,000 and borrow the balance. Because USDA Rural Development cannot release some of the committed grant funds until construction is complete, the town will use the DEQ Water Pollution Control State Revolving Fund to secure interim financing at 1.75% interest for approximately $665,000 to complete the project.

Environmentally sensitive characteristics such as wetlands, floodplains, threatened or endangered species, and historical sites are not expected to be adversely impacted because of the proposed project. Additional environmental impacts related to land use, water quality, air quality, public health, energy, noise, growth, and sludge disposal were also assessed. No significant long-term environmental impacts were identified.

Under Montana law, (75-6-112, MCA), no person may construct, extend, or use a public sewage system until DEQ has reviewed and approved the plans and specifications for the project. Under the Montana Water Pollution Control State Revolving Fund Act, DEQ may loan money to municipalities for construction of public sewage systems.

The DEQ, Engineering Bureau, has prepared this Environmental Assessment to satisfy the requirements of the Montana Environmental Policy Act (MEPA) and the National Environmental Policy Act (NEPA).

D. COMMENT PERIOD

Thirty (30) calendar days.

PURPOSE OF AND NEED FOR ACTION

Ryegate's wastewater treatment and collection system was installed in 1969. The collection system consists primarily of clay tile pipe and includes 46 manholes, and one pump station which pumps wastewater from six homes in the Second Farm Addition. Many of the clay pipes are installed at slopes slightly flatter than are required for new systems, but have functioned well and are in good condition based on the PER findings.

The two-cell facultative lagoon, completed in 1969, was initially designed for a population of 500 to provide for growth and was expected at the time to require periodic discharge to an unnamed dry slough connected to the Musselshell River. However, the anticipated growth never happened, and the town has not discharged effluent from the ponds since the lagoon system was constructed. This is thought to be due to groundwater leakage, evaporation and the lack of growth over the design period. The lagoons have never had sludge removed.

' The PER provides a description of the Ryegate wastewater system and detailed analysis of the performance and condition of the existing system. The system deficiencies and resulting impacts were identified as follows:

• According to the town, since their construction in 1969, the lagoons have never discharged. A water balance analysis within the PER supports a significant leakage rate from the lagoons to the underlying groundwater table.

• Groundwater modeling shows at least six domestic wells are within the zone where leaked (untreated) wastewater acts as a source of recharge to the aquifer and places the downgradient wells at risk of contamination. Lagoon leakage causes groundwater

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elevations to rise in a roughly concentric pattern (mound) from 0.6 to 2.9 feet. Because of the hydraulic influence from leakage from the primary lagoon, untreated wastewater poses a public health threat to those individuals living within approximately 2,500 feet from the lagoons and who use groundwater from wells completed in the alluvium.

• The overall condition of the lagoons is marginal to poor. The lagoon dikes have evidence of rodent activity and excessive plant growth. The dikes are heavily eroded. All of these conditions result in a compromised clay liner. The town has installed some rip rap along the interior of the dikes to stop erosion until the proposed improvements are completed.

• Modeling included in the PER shows that alluvial aquifer mounding from the lagoon leakage is impacting surface waters in the area. In particular, the oxbow south of the lagoon and the Musselshell River are impacted from lagoon leakage. Both of these surface waters are open to public access.

• There has been an increased need for maintenance on the lift station over the past several years. The lift station will be upgraded with the selected alternative.

Ryegate's proposed wastewater improvements project will include:

• Removal and land application of sludge. • Reconstruction of the lagoons and installation of a synthetic liner. • Addition of a storage cell that will fully evaporate the effluent (i.e. total retention

system design). • Reconstruction of the existing lift station and control system.

Ill. ALTERNATIVES INCLUDING THE PROPOSED ACTION

The Town of Ryegate's PER analyzed various alternatives to upgrade the single lift station, correct deficiencies with the treatment facility and remove and dispose of sludge. No-action alternatives were eliminated from further consideration for the proposed project because of serious health and safety concerns. Sludge removal and disposal plus reconstruction of the lagoons triggered the need for this EA and are the primary focus of this document.

The lift station that serves six homes within the community is at the end of its useful life and was determined to need upgrading. Three alternatives were evaluated to correct these lift station needs.

• No Action would result in continuing to operate with the existing pumps and controls. This option is not considered further as the existing pumps are in poor condition and beyond their useful life.

• LS-1 Total lift station replacement with a new submersible lift station was evaluated but was excluded due to high cost and potential dewatering issues associated with excavation at the lift station site.

• LS-2 Rehabilitation of the existing lift station with new pumps and controls presented the least cost alternative and would still provide for operator safety and result in a reliable outcome for the community. This alternative was selected as the only viable

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alternative.

Sixteen alternatives including the "No Action" alternative were screened for upgrading the existing lagoons. These are listed here:

• No Action • Facultative Lagoons with Total Retention • Mechanically Aerated Lagoons • Facultative Ponds with Storage and Irrigation • Activated Sludge Mechanical Treatment • Three Stage Biological Nutrient Removal (MLE Process) • Package Extended Aeration Activated Sludge (Biolac) • Package Membrane Bioreactor (MBR) • Package Sequencing Batch Reactor (SBR) • Oxidation Ditch • Constructed Wetlands • Packed Bed Treatment (Advantex) • Submerged Aerated Gravel Reactor (SAGR) • Facultative Lagoon with Polishing Bio Domes • New Complete Mix / Partial Mix Aerated Lagoons (Lemna) • Repair Existing Lagoons

Only two of these screened alternatives were deemed viable for Ryegate and are further discussed and evaluated. Those two alternatives are:

• T-1 Facultative Treatment Lagoons with Total Retention (evaporation}

Total retention treatment systems consist of large shallow ponds (4 - 6 feet deep) that rely on evaporation to eliminate the wastewater effluent. Therefore, no discharge permit is required. Solids are periodically removed from the ponds and properly disposed of via land farming or licensed solid waste facilities . These systems require considerably more land area than non-aerated discharging facultative or aerated lagoon systems due to their reliance on evaporation for effluent disposal. An arid climate and high evaporation rate is needed to apply this technology successfully.

The ponds must be lined to prevent wastewater seepage into the groundwater. The ponds should provide sufficient control structures and piping to allow some redirection of flows to prevent odors. The ponds are extremely simple to operate ahd maintain and they are reliable. For these reasons, they can be a very good alternative for small communities and are further considered.

• T-2 Facultative Treatment Lagoons with Storage and Irrigation (low rate land application}

Low-rate (irrigation) systems apply wastewater to the soil much less intensively than high rate systems (rapid infiltration ponds), but they require much more land area. The wastewater is typically treated in primary cells, stored in 8 to 9-foot deep storage cells during the winter months, and then applied to cropland or pasture during the summer months using sprinkler irrigation equipment. Secondary treatment must be achieved before irrigation, so lagoon technologies preceding irrigation are adequate.

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Wastewater is not required to be disinfected when the irrigation site is not accessed by the public (cropland or pasture) and a 200-foot buffer area and signage is used around the irrigated acreage to control public access. Remote locations are preferred because of the large size of the storage lagoons and concerns with mist from the irrigation system.

For 100% irrigation with no discharge, sufficient storage (180 to 230 days) is required during the winter in northern climates. This treatment technology has been excluded from the DE Q's non-degradation rules if the system is designed for 100 percent nitrogen uptake by the irrigated crops. This requirement means that the discharge of wastewater to the irrigation site is regulated and may only be applied at approved rates during the growing season. Five different property locations were considered for land application of effluent in the PER. None of the landowners were contacted to verify interest in using the effluent. The Ryegate area is known to have clay bearing soils which could result in salinity issues if effluent were used as an irrigation source. This alternative was considered further and compared against a total retention (evaporative) system.

To construct the new lined lagoon configuration for either treatment option considered, existing sludge must be removed and properly landfilled or land applied in accordance with EPA 503 Rules. These two sludge handling alternatives were considered within the PER, but hauling sludge from Ryegate to an approved landfill would be cost prohibitive due to the haul distance, so only land application for beneficial reuse was further considered. Agricultural land within a 5-mile radius of the community was screened for viable land application site. Five individual farm fields were discussed as possible alternative sites. The Town has determined the best option is to contain the haul distance within 5-miles of the lagoons and allow the contractor to identify the land application site within the bidding process. The contractor will be held to complying with the EPA 503 Regulations with respect to handling, application rates and methods.

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IV. COST COMPARISON - PRESENT WORTH ANALYSIS

A present worth (or life-cycle) analysis is a means of comparing alternatives in present day dollars and can be used to determine the most cost-effective alternative(s). An alternative with low initial capital cost may not be the most cost-efficient project if high monthly operation and maintenance costs occur over the life of the alternative. An interest rate of 4.0% over the 20-year planning period was used in the analysis.

TABLE 1 - ECONOMIC EVALUATION OF SLUDGE REMOVAL ALTERNATIVES

Alternative Total Capital Annual O&M Present Worth of Present Cost* Cost SalvaQe Value Worth

Alternative T-1: Facultative Treatment Lagoons with $1,672,000 $1,000 $354,100 $1,582,778 Total Retention Pond Alternative T-2: Facultative Treatment Lagoons with

$1 ,634,000 $11,700 $287,068 $1,770,998 Storage and Irrigation (low rate land aoolication) Alternative LS-2: Lift

$253,825 NA NA NA Station Rehabilitation Alternative S-1 : Land

$250,000 NA NA NA Application of SludQe

•capital costs include engineering, legal, administrative and construction costs.

V. RANKING AND SELECTION OF PREFERRED ALTERNATIVE

Selection of the preferred alternative was based on a scoring matrix comparing life-cycle­cost, operations and maintenance considerations, permitting issues, social impacts/benefits, environmental impacts, sustainability and land costs/availability. The ranking criteria considered are shown in Table 2. Each ranking criterion was given a weighting factor between 0-10 and then given a score between 0-10. Each score was multiplied by the weight to generate the total score. A score of 10 being the best and O the worst, with the alternative with the highest total score being the preferred alternative.

Table 2 Ranking of Two TreatmenUEnd Use Alternatives

Weighting T-1 Total Retention

Life Cycle Capital Costs 10 55

Operation & Maintenance Considerations 10 100

Permitting Issues 4 40

Social Impacts/Benefits 5 45

Environmental Impacts 5 50

Sustainability and Resiliency 4 40

Land Aquisition 6 60

Total 44 390

Rank 1 * Present worth life cycle cost analysis was used and reflects a 20-year lifespan with respect to operations and maintenance and end-of-life salvage values.

T-2 lrriaation

45 80 32 35 40 28 30

290

2

Both alternatives could meet the needs of the community. However, the total retention alternative provides a significant advantage with respect to land purchase or agreements

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and operations and maintenance over the irrigation alternative as depicted in Table 2. Irrigation with effluent in the Ryegate area could also be problematic with respect to salinity issues, as area soils may not tolerate application of salt bearing effluent well.

The PER has identified Facultative Treat.ment Lagoons with a Total Retention Pond as the preferred alternative for the Ryegate community. This treatment approach provides a low maintenance alternative that protects groundwater and if carefully protected via fencing and weed/tree maintenance will have at a minimum a 20-year design life.

VI. COST TO IMPLEMENT THE PREFERRED ALTERNATIVE

The PER and Uniform Funding Application prepared by the town establish a project cost of approximately $1,958,000 which includes all engineering, legal, administrative and construction costs. The town applied for and has received grants from the DNRC RRGL program for $125,000 and from USDA Rural Development for $1,100,000. The town proposes to contribute $68,000 and borrow the balance. Because USDA Rural Development cannot release some of the committed grant funds until construction is complete, the town will use the DEQ Water Pollution Control State Revolving Fund to secure interim financing at 1. 75% interest for approximately $665,000 to complete the project.

The average monthly residential rate for sewer service will increase from $19.50 to $33. 72 per month to generate the revenue necessary to repay the debt and provide for facility maintenance and reserve. The loan portion of the project will be funded with a revenue bond. The financial impact of this project is shown in Table 3. The proposed project will result in a monthly sewer cost per household that is 1.12% of the monthly median household income. Based on EPA guidance for project affordability, the increased sewer rate can be characterized as posing a minor to moderate economic hardship on some households.

a e - roJec or a I HY T bl 3 P . t Aff d bTt Monthly Sewer User Cost $33.72

Monthly Median Household Income (mMHI) * $3,021 User Rate as a percentaQe of mMHI 1.12%

* Based on US Census Bureau 2010 data

VII. AFFECTED ENVIRONMENT

A PLANNING AREA/MAPS

The Town of Ryegate is a small farming and ranching community located approximately 63 miles northwest of Billings, MT in Golden Valley County. It is located at the junction of US Highway 12 and Highway 238 (see Figure 1). The planning area boundary includes all the developed Ryegate community area along with the wastewater treatment lagoons shown in Figure 2. The proposed improvements are reflected in Figure 3. Sludge removal and land application for beneficial reuse is proposed for property within 5-miles of the lagoons.

B. FLOW PROJECTIONS

The flow estimates proposed by the engineer were based on water sales records provided by the Town. Based on water use data between 2014 through 2018 and inspection of the

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sewer system performed in 2015, the engineer concluded a design flow of 20,000 gallons per day would be used for design. A growth rate of 0% per year was established in the PER to establish design flow of 20,000 gallons per day. Historically, flows have not increased at any time of year due to infiltration into the collection system.

C. NATURAL FEATURES

The Town of Ryegate sits at an elevation of 3,650 feet and natural features consist of sandstone bluffs and the Musselshell River, which bracket the community on its northern and southern boundaries, respectively. The town's legal limits lay within these natural features and within the platted Milwaukee Land Company lots on the western extent of the town limits and the sewage lagoon on the eastern extent. The majority of the town's structures and population is located north of Highway 12, which bisects the community.

Soils in the vicinity of Ryegate within the Musselshell River Valley are generally fine-grained in nature with some gravelly horizons. Almost 70 percent of the soils investigated are considered by the USDA Natural Resource Conservation Service to be farmland of state importance. The remaining 30 percent are not considered prime farmland for several reasons, among them saline seep problems. Most of the prime farmland , from a national perspective, does not rank particularly highly with regard to productivity, with the best productivity index being 0.147 of a possible 1.0 ranking. Ranch and farm land in the area are generally irrigated.

VIII. ENVIRONMENTAL IMPACTS OF PROPOSED PROJECT

A. DIRECT AND INDIRECT ENVIRONMENTAL IMPACTS

1. Land Use/ Prime Farm Land

Vegetation in the study area is categorized by agriculture, outcropping bluffs and riparian zone vegetation along the meandering Musselshell River. Agricultural lands, located predominantly to the south, east and west of Ryegate, are considered farmland of statewide importance. These lands grow wheat, barley, oats, rye and hay grass. They are also used as pasture for livestock. Vegetation in riparian zones along the Musselshell River typically consist of cottonwoods, willow and Russian olive, with an understory of numerous forbs and grasses. No lands currently used for farming will be taken out of production and there will be no impacts on prime farm land.

The Web Soil Survey tool on the National Resource Conservation Service (NRCS) website identified two soil types within the project site as "prime farmland" soils. Soils near the Ryegate wastewater lagoons belongs to the Havre-Harlake Complex, which consists of loam to silty and clayey loam, and is considered well drained with a high capacity for water storage. The site is situated on a low terrace above the floodplain, the soils are generally alluvial in origin, and associated with older deposits of the Musselshell River.

Existing land use within the current sewer service area includes residential homes, a school and light commercial use. The new wastewater treatment facility will be constructed within the footprint of the existing lagoon based facility on property owned by the Highwood County Water & Sewer District.

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Sludge removed from the existing lagoons will be land applied at an application rate in compliance with EPA 503 Regulations as a soil amendment in a one-time application approach. The sludge has been sampled and tested for nutrients and various metals and pollutants to ensure it can be land applied . Sampling at the time of land application will be required of the contractor to ensure the sludge is appropriately applied and tilled into the soil as required. The sludge application will not impact Prime Farm Lands.

2. Floodplains and Wetlands

The project area does not lie within any FEMA-designated floodplains. However, the floodplain of the Musselshell River does extend to nearby land across Highway 12. The top of the lagoon berm lies above the anticipated 100-year floodplain elevation. The Montana Natural Heritage Program and National Wetlands Inventory show the presence of a variety of wetlands in the area. The project will not impinge on natural wetlands based on 1961 aerial photos of the site. See Section X: Agencies Consulted of this report for a summary of environmental agency comments.

3. Cultural Resources

The State Historic Preservation Office (SHPO) reviewed the proposed project. Because of the low likelihood cultural properties will be impacted due to the project site having been previously disturbed, SHPO advised that a cultural resource inventory was not needed. In the event cultural resources are discovered during work, SHPO asked to be contacted for guidance in that event.

4. Fish and Wildlife

Wildlife in the Ryegate area consists of deer, coyote, rabbit, mice and other small mammals, ducks, pheasants, sharp tail grouse, sage grouse, Hungarian partridge and various reptiles and amphibians. Endangered species within the search area include the bald eagle. Species of concern within the search area include:

. • Greater Sage Grouse; • Black-tailed Prairie Dog; • Golden Eagle; • Spiny Softshell Turtle; and • Northern Redbelly Dace (minnow).

Disturbed areas will be revegetated after construction activities. Because all work will be performed on the existing WWTF footprint on previously disturbed ground, no direct impacts are anticipated. See Section X: Agencies Consulted of this report for a summary of environmental agency comments.

5. Wild and Scenic Rivers

No designated Wild and Scenic Rivers will be impacted by the project.

6. Water Quality

The proposed lined lagoon system with full evaporation capacity will minimize direct

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discharge to groundwater from leakage and the resulting negative impacts to downgradient wells and the Musselshell River. Six current domestic wells are identified to be within this discharge plume and at risk of contamination.

The Musselshell River, in the area of the discharge, is located in USGS Hydrologic Code 10040201 , Upper Musselshell, and Montana stream segment MT40A001_020. This segment of the Musselshell is classified as C-3 (ARM 17.30.610(1)(e)(vi)). Class C-3 waters are to be maintained suitable for bathing, swimming, recreation and growth and propagation of non-salmonid fishes and aquatic life, waterfowl and furbearers. The quality of these waters is naturally marginal for drinking, culinary and food processing purposes,. agriculture and industrial water supply. Degradation which will impact established uses is not allowed (ARM 17.30.629(1)).

The primary purpose of the project is to eliminate the discharge from the Ryegate lagoons into groundwater and prevent a likely interconnection with the Musselshell River. The selected alternative (total retention evaporative lagoons) will allow the Town to achieve these treatment goals.

7. Sludge Disposal

Currently the Ryegate lagoons are filled with sludge that has accumulated over the 40 plus years the facility has operated. Those solids will need to be removed prior to reconstruction of the lagoon system. It is intended that all sludge (biosolids) will be removed from the existing lagoons and land applied in accordance with Federal 40 CFR 503 sludge disposal regulations in a one-time application. The Part 503 regulations contain specific numerical limits and other requirements for heavy metals, pathogens and vector attraction. A potential contractor must perform verification of sludge quantity, in-place sludge nutrient content, identification of a disposal site and nutrient testing of soils at the application site. The final sludge disposal plan utilizing this information must be submitted to the DEQ for review and concurrence prior to sludge disposal. Earlier testing of the Ryegate sludge has been performed and those results are included in the PER. This testing has determined the sludge meets EPA land application criteria at the time it was sampled.

Lagoon based solids tend to be anaerobic and have a strong sour smell. There will be some associated odors generated during the dewatering, removal and hauling process. Once those solids are tilled into the land application area, odors rapidly decrease so the impact is a short-term impact.

8. Air Quality

Short-term negative impacts on air quality are expected to occur during construction from heavy equipment in the form of dust and exhaust fumes. Proper construction practices will minimize this problem. Project specifications will require dust control. Removal of sludge within the existing lagoons, which will need to be completed will likely result in short-term odor issues, but best management practices should result in minimizing these odors. The removal of sludge will reduce the intensity of turn­over events during spring and fall seasons that have resulted in odor complaints in the past. As sludge builds back up in the primary treatment lagoon, it will need to be removed in future years to prevent this turn-over issue. In the long-term, odor

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control associated with the new treatment facility will be an improvement over existing conditions.

9. Public Health

Public health protection is safeguarded by the proposed project. The proposed wastewater treatment facility will minimize leakage of poorly treated wastewater, thereby reducing the potential to pollute both groundwater and surface water. Sludge removal from the lagoons and land application for beneficial reuse will be in accordance with EPA's Part 503 regulations.

10. Energy

The proposed treatment facility is estimated to have the same energy footprint as the current system. The replacement of pumps within the existing lift station will not result in an increase in energy use.

11 . Noise

Short-term impacts from excessive noise levels may occur during the construction activities. The construction period will be limited to normal daytime hours to avoid early morning or late evening construction disturbances. Therefore, no significant long-term impacts from noise should occur.

12. Environmental Justice

Environmental Justice Executive Order 12898: The proposed project will not result in disproportionately high or adverse human health or environmental effects on minority or low-income populations. The economic impact will ultimately affect all users of the system proportionately to the taxable value of the system if a general obligation bond were used to secure a loan for the cost of the project. No disproportionate effects among any portion of the community is expected.

13. Growth

Improvements to the WWTP will be a positive feature for the community. The growth estimate used within the PER is for no growth within the community over the 20-year design life of the project. Should growth exceed these estimates, the Town will have to add storage capacity or identify a land application area that can be added to support growth beyond that projected as needed.

14. Cumulative Effects

The proposed wastewater improvements are not expected to result in any cumulative effects. The reduction of groundwater discharge will allow the aquifer to recover to pre-discharge levels and may allow area wells to recover with respect to water quality.

8. UNAVOIDABLE ADVERSE IMPACTS

Short-term construction related impacts (i.e. , noise, odor, dust, traffic disruption, etc.) will occur, but should be minimized through proper construction management and

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communication with business and homeowners. Energy consumption during construction cannot be avoided.

IX. PUBLIC PARTICIPATION

A Town Council work session was held on March 24, 2016 which allowed for public attendance to learn about the proposed project. Public participation for this project occurred on April 11 th , 2016 at a special meeting which was noticed in the local Times-Clarion newspaper classified section. A vote to approve the recommendations made in the 2016 PER was held on April 11, 2016 by the Town Council and passed. This action by the Council accepted the plan to build a new total retention facultative lagoon facility and to upgrade the existing lift station with new pumps and controls

Public agencies of interest or jurisdiction with respect to project permits, easements and encroachments have been contacted and have been supportive of the proposed project. Permitting agencies will be further contacted with project applications as needed to secure appropriate authorizations for the work prior to any construction activity.

Letters of support for the project are contained in the PER. In addition to several letters of support from residential customers, the Lower Musselshell Conservation District, Golden Valley County Commission, Ryegate Public School Board, and local Fire Department each provided letters of support for the project

X. AGENCY ACTION, APPLICABLE REGULATIONS AND PERMITTING AUTHORITIES

No additional permits are required from the SRF program of the DEQ after review and approval of the submitted plans and specifications is completed. However, coverage under a storm water general and groundwater dewatering discharge permits, if necessary, are required from the DEQ Water Protection Bureau prior to beginning construction. Land application of the sludge (biosolids from the existing lagoons) requires that an EPA 503 process be implemented and reviewed by the DEQ SRF program for concurrence.

XI. RECOMMENDATION FOR FURTHER ENVIRONMENTAL ANALYSIS

[ ] EIS [ ] More Detailed EA [ X ] No Further Analysis

Rationale for Recommendation: Through this EA, the DEQ has verified that none of the adverse impacts of the proposed Big Sky County Water and Sewer District 363 wastewater treatment project are significant. Therefore, an environmental impact statement is not required. The environmental review was conducted in accordance with the Administrative Rules of Montana (ARM) 17.4.607, 17.4.608, 17.4.609, and 17.4.610. The EA is the appropriate level of analysis because none of the adverse effects of the impacts are significant.

XII. REFERENCE DOCUMENTS

The following documents have been utilized in the environmental review of this project and are considered to be part of the project file:

1. Wastewater Preliminary Engineering Report, Ryegate MT, May 2016, prepared by Great West Engineering (PER).

2. Uniform Application Form for Montana Public Facility Projects dated, July 2019, prepared

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by the Town of Ryegate.

XIII. AGENCIES CONSUL TED

The following agencies have been contacted in regard to the proposed construction of this project:

1. The U.S. Fish and Wildlife Service reviewed the proposed project and replied that they "anticipate no effects to threatened, endangered, or other trust species; therefore, the Service has no concerns with the proposal".

2. The Department of Natural Resources and Conservation {DNRC) reviewed the proposed project and determined that the project is not located in a designated 100-year floodplain currently, but that new floodplain work was ongoing within the study area. They advised close communication with the local floodplain officer.

3. The Montana Historical Society's State Historic Preservation Office (SHPO) reviewed the proposed project. According to their records, there have been no previously recorded sites within the designated search locales. Based on the previous disturbance in the area they feel there is low likelihood cultural properties will be impacted. However, should cultural materials be inadvertently discovered during the project, SHPO must be contacted and the site investigated.

4. The U.S. Department of the Army Corps of Engineers (USCOE) reviewed the proposed project and because no fill material will be placed either temporarily or permanently in waters of the U.$. , no USCOE permit will be required.

5. The Montana Department of Fish, Wildlife and Parks indicated that they did not have any comments regarding the proposed improvements in the October 2016 Preliminary Engineering Report prepared for the District by Anderson Montgomery Consulting Engineers.

6. The Montana Natural Heritage Program was contacted regarding the proposed project and found 4 species of concern that live within the project area. Impacts to these plants and animals are expected to be non-significant for a variety of reasons, including: • The project site is within a previously disturbed footprint of the existing wastewater

treatment facility and immediately adjacent to homes within the development, • The construction will not result in new open water areas which could attract the bird

species of concern, • Construction will occur during the summer when the animals are in their best condition

and when ground animals have the most mobility, and • The construction period is relatively short.

Michele Marsh, P.E.

Date

Date

Page 13 of 14

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Figure 1 Project Location Map

Page 14 of 14

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FIGURE 2 PLANNING AREA

TOWN OF RYEGATE WASTEWATER SYSTEM IMPROVEMENTS

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INLET AND DIVERSION CONTROL STRUCTURE

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INLET STRUCTURE

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TOTAL LAGOON FOOTPRINT=11.5 ACERS

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TREATMENT LAGOON 1.35ACRES

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EXISTING LAGOON

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TOP OF EMBANKMENT 10' WIDE FOR VEHICLE ACCESS

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STORAGE LAGOON 7.79ACRES

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Figure 3 Proposed Total Retention

Lagoon Footprint

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WASTEWATER SYSTEM IMPROVEMENTS