APPENDIX D Draft 404(b)1 Analysis This page intentionally left blank. 404(b)(1) Evaluation US 93 Evaro-Polson EIS SEIS Ninepipe/Ronan MDT NH-F 5-1 (9) 6F Control No. B744 Prepared for: Montana Department of Transportation October 2005 Prepared By: 404(b)(1) Evaluation SECTION 1. INTRODUCTION........................................................................................................................1 SECTION 2. PROJECT DESCRIPTION..........................................................................................................1 2. A. LOCATION.................................................................................................................................................1 2.B. GENERAL DESCRIPTION.............................................................................................................................4 Project Background......................................................................................................................................4 Project Alternatives......................................................................................................................................4 2.C. AUTHORITY AND PURPOSE.........................................................................................................................8 2.D. GENERAL DESCRIPTION OF THE DREDGED OR FILL MATERIAL..................................................................8 2.D.1 General Characteristics of Material..................................................................................................8 2.D.2 Quantity of Material............................................................................................................................8 2.D.3. Source of Material............................................................................................................................9 2.E. DESCRIPTION OF THE PROPOSED DISCHARGE SITES...................................................................................9 2.E.1 Location of Sites.................................................................................................................................9 2.E.2 Size of Sites.........................................................................................................................................9 2.E.3 Type of Sites........................................................................................................................................9 2.E.4 Types of Wetland Habitats................................................................................................................21 2.E.5 Timing and Duration of Discharge...................................................................................................21 2.F. DESCRIPTION OF DISPOSAL METHOD........................................................................................................21 2.F.1 Roadway Widening...........................................................................................................................22 2.F.2 Bridge and Culvert Construction......................................................................................................22 SECTION 3: FACTUAL DETERMINATIONS (SECTION 230.11)............................................................22 3.A. PHYSICAL SUBSTRATE DETERMINATIONS................................................................................................22 3.A.1 Substrate Elevation and Slope..........................................................................................................22 3.A.2 Compare Fill Material and Substrate at Discharge Site..................................................................23 3.A.3 Dredged/Fill Material......................................................................................................................23 3.A.4 Physical Effects on Benthos, Invertebrates, and Vertebrates...........................................................23 3.A.5 Erosion and Accretion Patterns........................................................................................................24 3.A.6 Actions Taken to Avoid and Minimize Impacts.................................................................................24 3.B. WATER CIRCULATION, FLUCTUATION AND SALINITY DETERMINATIONS.................................................25 3.B.1 Water................................................................................................................................................25 3.B.2 Current Patterns and Circulation.....................................................................................................26 3.B.3 Normal Water Level Fluctuations....................................................................................................27 3.B.4 Salinity Gradients.............................................................................................................................27 3.B.5 Actions Taken to Avoid and Minimize Impacts.................................................................................27 3.C. SUSPENDED PARTICULATE/ TURBIDITY DETERMINATIONS......................................................................28 3.C.1 Expected Changes in Suspended Particulate and Turbidity Levels in the Vicinity of the Disposal Site..............................................................................................................................................................28 3.C.2 Effects on Chemical and Physical Properties of the Water Column................................................28 3.C.3 Effects on Biota................................................................................................................................29 3.C.4 Actions Taken to Avoid and Minimize Impacts.................................................................................29 3.D. AQUATIC ECOSYSTEM AND ORGANISM DETERMINATIONS......................................................................30 3.D.1 Effects on Special Aquatic Sites.......................................................................................................30 3.D.2 Effects on Threatened and Endangered Species and Their Habitats...............................................32 3.D.3 Effects on Other Animals.................................................................................................................37 3.D.4 Effects on Terrestrial Plants............................................................................................................37 3.D.5 Actions Taken to Avoid and Minimize Impacts................................................................................38 3.D.6 Compensatory Actions Taken to Minimize Impacts.........................................................................40 3.D.7 Monitoring of Mitigation Actions.....................................................................................................40 3.E. POTENTIAL EFFECTS ON HUMAN USE CHARACTERISTICS........................................................................40 3.F. DETERMINATION OF CUMULATIVE EFFECTS ON THE AQUATIC ECOSYSTEMS...........................................41 US 93 Ninepipe/Ronan Improvement Project i Skillings-Connolly MDT NH-F 5-1 (9) 6F Control No. B744 404(b)(1) Evaluation 3.G. DETERMINATION OF SECONDARY EFFECTS ON THE AQUATIC ECOSYSTEMS............................................41 LEAST DAMAGING PRACTICABLE ALTERNATIVE.............................................................................................42 REFERENCES...................................................................................................................................................43 List of Figures Figure 1: Vicinity Map...............................................................................................................2 Figure 2: Location of Project on the US 93 Corridor.....................................................................3 List of Tables Table 1. Characteristics of wetlands in the US 93 Ninepipe/Ronan improvement project corridor...............................................................................................................................10 Table 2. Surface waters located in the US 93 Ninepipe/Ronan improvement project corridor........20 Table 3. Estimated wetland impacts in hectares (acres) by wetland type in the rural portion of the US 93 Ninepipe/Ronan project corridor a.....................................................................31 Table 4. Estimated impacts in hectares (acres) by wetland type in the Ronan segment of the US 93 Ninepipe/Ronan project corridor...................................................................................31 Table 5. Total Estimated Wetland Impacts.......................................................................................32 US 93 Ninepipe/Ronan Improvement Project ii Skillings-Connolly MDT NH-F 5-1 (9) 6F Control No. B744 404(b)(1) Evaluation Section 1. Introduction The 404(b)(1) Guidelines, found in Title 40 of the Code of Federal Regulations, Part 230, are the substantive criteria used in evaluating discharges of dredged or fill material into Waters of the United States under Section 404 of the Clean Water Act and are applicable to all 404 permit decisions. Fundamental to these Guidelines is the precept that dredged or fill material should not be discharged into the aquatic ecosystems unless it can be demonstrated that such discharges would not have unacceptable adverse impacts either individually or in combination with known and/or probable impacts of other activities affecting the ecosystems of concern. Subpart B of the guidelines establishes four conditions, which must be satisfied to make a finding that a proposed discharge complies with the guidelines. Section 230.10 provides that: a) Except as provided under Section 404(b)(2), no discharge of dredged material shall be permitted if there is a practicable alternative to the proposed discharge which would have less adverse impact on the aquatic ecosystem, so long as the alternative does not have other significant adverse environmental consequences. b) No discharge of dredged or fill material shall be permitted if it violates state water quality standards, Section 307 of the Clean Water Act, or the Endangered Species Act of 1973. c) No discharge of dredge or fill material shall be permitted which would cause or contribute to significant degradation of the waters of the United States. d) Except as provided under Section 404(b)(2), no discharge shall be permitted unless appropriate and practicable steps have been taken which will minimize adverse impacts of the discharge on the aquatic ecosystem. Mitigation to offset significant and insignificant adverse impacts may be developed which could result in bringing a project into compliance with the guidelines. Impacts must be avoided to the maximum extent practicable and remaining unavoidable impacts will then be mitigated to the extent appropriate and practicable by requiring steps to minimize impacts and finally, by compensation for loss of aquatic resource values. This evaluation represents the views of MDT on how the proposed action complies with the requirements of the 404(b)(1) Guidelines. It is not intended to represent the U.S. Army Corps of Engineers (USACE) views, conclusions, or their final 404(b)(1) Evaluation. Section 2. Project Description 2. A. LOCATION The Federal Highway Administration (FHWA), the Montana Department of Transportation (MDT), and the Confederated Salish and Kootenai Tribes (CSKT) propose to improve an 18-kilometer (11.20-mile) section of the existing U.S. Highway 93 (US 93) corridor in Montana. US 93 serves as the major north-south transportation corridor in western Montana (Figure 1, Vicinity Map). The US 93 Ninepipe/Ronan improvement project extends from Dublin Gulch Road/Red Horn Road to the proposed project’s northern terminus at Baptiste Road/Spring Creek Road (Figure 2, Location of Project on the US 93 Corridor). The project corridor lies entirely within Lake County, on the Flathead Reservation, which is governed by the Confederated Salish and Kootenai Tribes. The Ninepipe/Ronan area is a wetland complex, located partially within a National Wildlife Refuge, which includes thousands of pothole wetlands, which offer diverse wildlife habitat. The Post Creek drainage basin, an important corridor for fish and wildlife, is also located within the project area. US 93 Ninepipe/Ronan Improvement Project 1 Skillings-Connolly MDT NH-F 5-1 (9) 6F Control No. B744 404(b)(1) Evaluation Prime farmland acreage is prevalent along the unincorporated project segments of US 93 to the north and south of the City of Ronan. Residential and commercial activity is primarily limited to single family residences on large lots. Commercial activity is often of single proprietors operating from residential properties. Within the city limits of Ronan, natural habitats are limited to Ronan Spring Creek, which crosses US 93, and a limited number of wetlands near the northern terminus of the project corridor. US 93 is a major commercial corridor through the City of Ronan, with adjacent businesses providing a variety of motorist related services. 2.B. GENERAL DESCRIPTION Project Background In 1996, the FHWA, MDT, and CSKT issued the U.S. Highway 93 – Evaro to Polson – Missoula and Lake Counties, Montana: Final Environmental Impact Statement and Section 4(f) Evaluation; FHWA-MT-EIS-95-01-F; F 5-1(9)6 (FHWA and MDT 1996) (referred to as the US 93 Evaro to Polson FEIS) consistent with requirements of the National Environmental Policy Act (NEPA). The Final Environmental Impact Statement (FEIS) described the impacts from improvement of a 90.6 km (56.3 mile) section of US 93 from Evaro to Polson. A Supplemental Environmental Impact Statement (SEIS) is being prepared concurrently with this 404(b)(1) Evaluation that will describe impacts to the Ninepipe/Ronan section of US 93. The SEIS is being prepared as a supplement to the FEIS to examine various alternatives for improving transportation in the project corridor and to identify the associated environmental impacts. The US 93 Evaro to Polson FEIS described the proposed project and alternatives, and the social, economic, and environmental impacts of the corridor project. A Record of Decision (ROD) was issued on August 12, 1996; however, the ROD deferred making a decision on lane configurations, mitigation measures, and a Section 4(f) determination until agreement was reached by FHWA and MDT, along with their cooperating agency, the CSKT. Representatives from MDT, FHWA, and CSKT (referred to as the “three governments” or “proponents”) then negotiated and signed the Memorandum of Agreement-US 93 Evaro to Polson (MDT, FHWA, and CSKT 2000) (referred to as the US 93 Corridor MOA). The US 93 Corridor MOA, dated December 20, 2000, lays out the preferred conceptual roadway improvements, including lane configurations, design features, and mitigation measures for 50 kilometers (30.6 miles) of US 93 from Evaro to the Dublin Gulch Road/Red Horn Road intersection (RP 37.1) near Saint Ignatius and for 17.4 kilometers (10.8 miles) of US 93 from the Baptiste Road/Spring Creek Road intersection near Ronan (RP 48.3) to the MT 35 intersection near Polson (RP 59.1). The US 93 Corridor MOA does not include an 18-kilometer (11.2-mile) section between the Dublin Gulch Road/Red Horn Road intersection (RP 37.1) and the Baptiste Road/Spring Creek Road intersection (RP 48.3), which is called the US 93 Ninepipe/Ronan project corridor. The three governments agreed to prepare a Supplemental EIS (referred to as the US 93 Ninepipe/Ronan SEIS) for the Ninepipe/Ronan section. It was agreed a supplement was needed to explore possible alternate alignments around the environmentally sensitive Ninepipe glacial pothole wetland complex, and to study in more depth the effects of the highway improvement on the wetlands and wildlife in the corridor. Project Alternatives The SEIS evaluates the following alternatives: US 93 Ninepipe/Ronan Improvement Project 4 Skillings-Connolly MDT NH-F 5-1 (9) 6F Control No. B744 404(b)(1) Evaluation No Action The No Action Alternative will perpetuate the existing highway with no substantial improvements. Any improvements to the existing system would be considered on individual merits and could include spot safety improvements, channelization at intersections, climbing lanes, and signalization as dictated during the coming years. Although the No Action Alternative does not meet the purpose and need for the proposed action, it is evaluated in detail in accordance with the National Environmental Policy Act (NEPA) and the Council on Environmental Quality (CEQ) regulations. Lane Configuration Alternatives All of the alternatives under consideration represent various combinations of the lane configurations included in the following descriptions. The 1996 US 93 FEIS defined the four-lane configurations included in the study as follows: Lane configuration A is a two-lane two-way highway with auxiliary lanes. Where needed, passing lanes will be added for short distances, designated left-turn bays will be constructed at important intersections, and continuous two-way left-turn center medians will be constructed where there are high numbers of intersections and driveways. Lane configuration B is a four-lane highway with two traffic lanes in each direction. Designated left-turn bays will be constructed at important intersections. Lane configuration C is a four-lane highway with a continuous two-way left-turn center median. Lane configuration D is a four-lane highway with a divided, unpaved center median. Designated left-turn bays will be constructed at important intersections. The alternatives studied in the SEIS include these lane configurations and variations of them singly or in combinations over the length of the proposed project. All of the action alternatives will include reconstruction of the existing roadway. The reconstruction will provide for curvilinear horizontal alignment roughly following the existing roadway to minimize impacts to adjacent lands. Included will be construction of wider shoulders and revision of the vertical alignment to accommodate structures crossing waterways, streams, and riparian areas. Many of these structures will also serve as wildlife crossings. All slopes will follow the slope tables for rural and urban principal arterials as shown in the MDT Design Standards, except as modified in the preliminary project design (see Appendix A of the US 93 Ninepipe/Ronan Improvement Project Draft SEIS). Rural Alternatives The following alternatives were studied in detail. Impacts are set forth for two segments in the rural portion of the proposed project. US 93 Ninepipe/Ronan Improvement Project 5 Skillings-Connolly MDT NH-F 5-1 (9) 6F Control No. B744