Seiad Creek Legacy Roadbed Rehabilitation Project Soil Report

Transcription

1 KLAMATH NATIONAL FOREST Seiad Creek Legacy Roadbed Rehabilitation Project Soil Report Happy Camp Oak Knoll Ranger District Joe Blanchard 5/21/2014 Prepared by Joe Blanchard Forest Soil Scientist Klamath National Forest 1711 S. Main Street, Yreka, CA

2 Contents Executive Summary... 3 Introduction... 5 Affected Environment... 6 Environmental Consequences... 7 Issue #1- Soil stability... 7 Rules... 7 Methods... 8 Effects Analysis... 9 Conclusion Issue #2- Soil organic matter Rule Method Effects Analysis Conclusion Issue #3- Soil Structure Rule Method Effects Analysis Conclusion Compliance with Law, Policy, and Regulation Literature Cited Appendices

3 Tables and Figures Table 1. Soil Cover Guidelines for Projects from Klamath LRMP... 7 Table 2. Soil Stability Indicator Condition Assessment in FSM... 8 Table 3. Surface Organic Matter and Soil Organic Matter Indicator Condition Assessment in FSM Table 4. Soil Strength and Structure Indicator Condition Assessment in FSM Table 5. Compliance with Law, Policy, and Regulation Table 6. Proposed Treatments and Soil Map Units Table 7. Soil Survey Information for the Project Area Table 8. Soil erosion hazard rating (EHR) for the soils in the Project Area Figure 1. Order 3 Soil Survey Map of the Project Area

4 Executive Summary Analysis Indicators and Methodology Three analysis indicators for effects on the soil resource are soil stability, soil organic matter, and soil structure. All of these indicators can affect a soil s ability to support plant growth; soil stability can also affect hydrologic function. The associated law, policy or regulation including standards and guidelines from the KNF Forest Plan and soil condition indicators from the Forest Service Manual (FSM) 2500, Chapter 2550-Soil Management, are used to establish a set of rules for each indicator. The measurement of analysis indicators is discussed further in the body of the Soil resource report as are the condition classes used to measure each indicator. The projected soil stability, soil organic matter, and soil structure condition class ratings were estimated using field experience and best available science. Good soil condition represents an undisturbed state in which desired conditions are fully met; fair condition represents a slightly disturbed state with desired conditions being partly met; and poor condition represents a heavily disturbed state with desired conditions not being met. For the areas that have been rated with poor condition, a substantial and permanent impairment does not exist and soil function is expected to recover naturally over a period of decades. Standards and Guidelines in the Forest Plan require that soil productivity and stability are maintained or enhanced through management activities. Maintaining the vast majority of the project area in the good soil condition will ensure that Forest Plan Standards are being met. A more detailed definition of good, fair, and poor condition class for each indicator is included the Soil resource report, available on the project website. Spatial and Temporal Context For all analysis indicators, the analysis area is spatially bounded by the activity units because this is where soil disturbing activities take place. The analysis is bounded in time by the foreseeable future period during which effects of this project may persist as detectable, noticeable effects. Soil cover, as it affects soil stability, can recover quickly as needles and other organic debris is deposited on the forest floor. The temporal boundary for soil stability is 5 years. Soil organic matter can take years to decades to rebuild after it is lost through displacement or erosion. The temporal boundary for surface and soil organic matter is 30 years. Once compacted, soil structure and macroporosity can remain affected for decades. The temporal boundary for soil structure is 30 years. Affected Environment The soils in the project area can be grouped into three categories that differ by parent material or the bedrock from which the soil formed. Clallam and Holland soil Families are found in the lowest elevations in the Project Area, including soil map units 113, 115, and 141. These soils are deep gravelly and very gravelly loams formed from metavolcanic parent material. Soil productivity rating is moderate and Maximum EHR is low to high. Maximum erosion hazard rating are based on little or no vegetative cover present and the occurrence of a 2-year, 6-hour storm event. In the middle of the Project Area, soil map units 143 and 183 are formed from metamorphic parent material and include Holland, Skalan, and Clallam soil Families. These soils are deep gravelly and very gravelly loams. Soil productivity rating is moderate to high and Maximum EHR is high. At higher elevations in the project area the soils from the 3

5 Olete and Parks Families have formed from ultramafic and peridotite parent material and include soil map units 157, 168, and 171. These are very gravelly loams and gravelly fine sandy loams. Due to shallow soils and nutrient deficiencies in the parent material, soil productivity ratings are lower than the rest of the project area, ranging from moderate to low. Maximum EHR is very high due to the low infiltration rates and runoff from rock outcroppings. A soil map and table of map characteristics is attached in Appendix A An assessment of current soil condition is based on the results of the field review. Proposed treatment sites were stratified by soil type and so that at least one site in each soil type was evaluated for the current conditions for soil stability, soil organic matter, and soil structure. The roadbeds that were visit included recently used logging road (48N20.2), old logging roads (48N20.2 and 46N50.3), an old logging spur road (48N20.6), and an old mining access road (48N20.1). Environmental Consequences Alternative 1 Direct and Indirect Effects There will be no immediate or short-term effect of this alternative on the soils, as soil disturbing activities will not take place. In the short term, soil cover for erosion protection will not change in the project area. Leaving legacy sediment sources untreated will have a long-term negative impact on desired conditions for soil stability and soil organic matter; soil loss is expected to occur when legacy sediment sites such as fill material and landslides fail. Soil structure conditions will remain the same in the short-term, with very slow long-term natural recovery of old roadbeds. Cumulative Effects Past actions including timber harvest and mining are evident on the landscape in the project area and are reflected in the discussion of the affected environment. There are reasonably foreseeable future actions that could overlap areas where activities in this project are proposed. These projects are detailed in Appendix C of the EA and include underburning and non-commercial thinning. Underburning and noncommercial thinning will have minor impacts to soil cover and no impacts to soil organic matter and soil structure. Adding the effects of the no action to the effects of past, present and reasonable foreseeable future actions is not expected to have measurable effects on the soil resource and, therefore, no significant cumulative effects will occur. Alternative 2 Direct and Indirect Effects The proposed activities that may impact soil stability, soil organic matter, and soil structure desired conditions include fill removal, re-contour/runoff dispersal, hand treatments, and clearing of roads for heavy machinery access. Implementation of PDFs will reduce the potential for negative effects from these activities. Wet Weather Operation Standards (WWOS) will be used to guide all project activities during periods of wet weather to insure operations do not result in erosion, puddling, rutting, or excessive soil compaction. The overall footprint of disturbance will be limited by using minimum disturbance methods and clearing widths on existing roadbeds. Soil stability will be maintained post-project by covering 4

6 disturbed area with slash or mulch. Alternative 2 will maintain adequate soil cover to maintain soil stability, protect soil organic matter, and maintain soil structure at levels sufficient to protect soil productivity and prevent soil erosion. A full description of how the proposed activities may impact soil function can be found in the Soil resource report. Cumulative Effects Past actions including timber harvest and mining are evident on the landscape in the project area and are reflected in the discussion of the affected environment. There are reasonably foreseeable future actions that could overlap areas where activities in this project are proposed. Reference current SOPA. Underburning and non-commercial thinning will have minor impacts to soil cover and no impacts to soil organic matter and soil structure. Adding the effects of the no action to the effects of past, present and reasonable foreseeable future actions is not expected to have measurable effects on the soil resource and, therefore, no significant cumulative effects will occur. Compliance with law, policy, regulation and the KNF Forest Plan All alternatives comply with relevant law, policy, regulation and the KNF Forest Plan. Forest Plan compliance is documented in the Forest Plan Conformance table, available on the project website. Introduction This report addresses the issues of soil stability, soil organic matter, and soil structure in the Seiad Creek Legacy Roadbed Rehabilitation Project (Project). Potential impacts to soil function are analyzed and mitigated through project design features (PDFs) and best management practices (BMPs). The Happy Camp Oak Knoll Ranger District of the Klamath National Forest is proposing to hydrogically stabilize approximately 5.8 miles of existing roadbeds that have inventoried legacy sites. Approximately 40 sediment sources, many of which are legacy sites, would be treated during hydrologic stabilization of the existing roadbeds. Legacy site treatment include, culvert and fill removal from stream channels and swales, and runoff dispersal by reshaping or re-contouring roadbeds prism fills and hand crew treatments without heavy machinery. Heavy machinery was assumed to perform most of these treatments unless hand treatments were specified. The Seiad Creek Legacy Roadbed Rehabilitation project is located within the Seiad Creek watershed a 29 square mile tributary to the Klamath River. The southernmost portion of the project area lies approximately two miles east of Seiad Valley, California in Siskiyou County, in Township (T) 46 North (N), Range (R) 11 West (W), Sections 5, 7, 8; T 47 N, R 11 W, Sections 18, 20, 27, 28, 32-34; and T 47 N, R 12 W, Section 13, Mount Diablo Meridian. The 10,630-acre project area is defined by the East Fork, West Fork and Middle Seiad Creek 7 th field watersheds that define the boundary. Elevation ranges from 2,000 to 6,000 feet. 5

7 Affected Environment Soils information for the project area was obtained from the Klamath National Forest Order 3 Soil Survey (Foster and Lang, 1994). This mapping was field verified for accuracy. The soils in the project area can be grouped into three categories that differ by parent material or the bedrock from which the soil formed. Clallam and Holland soil Families are found in the lowest elevations in the Project Area, including soil map units 113, 115, and 141. These soils are deep gravelly and very gravelly loams formed from metavolcanic parent material. Soil productivity rating is moderate and Maximum EHR is low to high. Maximum erosion hazard rating are based on little or no vegetative cover present and the occurrence of a 2-year, 6-hour storm event. In the middle of the Project Area, soil map units 143 and 183 are formed from metamorphic parent material and include Holland, Skalan, and Clallam soil Families. These soils are deep gravelly and very gravelly loams. Soil productivity rating is moderate to high and Maximum EHR is high. At higher elevations in the project area the soils from the Olete and Parks Families have formed from ultramafic and peridotite parent material and include soil map units 157, 168, and 171. These are very gravelly loams and gravelly fine sandy loams. Due to shallow soils and nutrient deficiencies in the parent material, soil productivity ratings are lower than the rest of the project area, ranging from moderate to low. Maximum EHR is very high due to the low infiltration rates and runoff from rock outcroppings. A soil map and table of map characteristics is attached in Appendix A An assessment of current soil condition is based on the results of the field review. Proposed treatment sites were stratified by soil type and so that at least one site in each soil type was evaluated for the current conditions for soil stability, soil organic matter, and soil structure. The roadbeds that were visit included recently used logging road (48N20.2), old logging roads (48N20.2 and 46N50.3), an old logging spur road (48N20.6), and an old mining access road (48N20.1). Soil Stability Soil stability condition ranged from Fair to Poor at the sites evaluated for current condition. At sites rated as Fair, only minor portions of roadbeds lack effective erosion control measures; most of the roadbed has re-vegetated, providing adequate soil cover to prevent erosion. For the sites rated as Poor, a majority of the roadbed lacks erosion control features and large gullies extend most of the length of the roadbed. Soil Organic Matter Soil organic matter condition ranged from Fair to Poor at the sites evaluated for current condition. Roadbeds with Fair ratings were areas with lower amounts of soil displacement due to road building. These were typically old logging roads on ridges. Roadbeds with Poor ratings were typically on steeper slopes where large cut and fill slopes had displaced enough topsoil to affect soil productivity. Soil Structure Soil structure and macro-porosity condition ranged from Fair to Poor at the sites evaluated for current condition. Old logging spurs that had been abandoned for decades had only minor increases in soil density and changes to soil structure compared to adjacent undisturbed soil and were given a Fair rating. Recently used logging roads, mining access roads, and some sections of old logging roads had major 6

8 increases in soil density and changes to soil structure compared to adjacent undisturbed sites and were given a Poor rating. Environmental Consequences The environmental consequences for this project are analyzed through a process of determining an issue for the soil resource, establishing appropriate rules, analyzing the issue using those rules, and making conclusions based on those analyses. Three issues impacting the soil resource were identified as soil stability, soil organic matter, and soil structure (Powers et al., 2005). The associated law, policy or regulation including standards and guidelines (S&G) from the Klamath National Forest Land and Resource Management Plan (LRMP) (USDA Forest Service, 2010) and soil condition indicators from the Forest Service Manual (FSM) 2500, Chapter Soil Management (USDA Forest Service, 2012) are used to establish a set of rules for each issue. The methods used to analyze each issue are described including temporal and spatial boundaries as well as activities included in the cumulative effects. The direct, indirect, and cumulative effects of proposed project activities are described in general terms and an indicator or measure for comparison is provided. Conclusions are made about the effects of each alternative based on the indicator or measure. Issue #1- Soil stability Soil stability can affect a soil s ability to support plant growth and proper hydrologic function. Forests generally have very low erosion rates unless they are disturbed in a manner that exposes bare soil to the erosive energy of water and wind. The desired condition for stable soils is adequate levels of soil cover to prevent erosion. This generally means soil cover levels are 50% or greater and is well distributed throughout the area. Rules 1. LRMP S&G 3-1: Plan and implement land management activities to maintain or enhance soil productivity and stability. 2. LRMP S&G 3-2: With the exception of roads, permanent facilities or other projects that will permanently occupy a site, the following levels of total soil cover should be maintained at the stand level to reduce the potential of soil erosion: Table 1. Soil Cover Guidelines for Projects from Klamath LRMP Soil Texture Group Slope Group % Machine Disturbed Areas (machine pile, mastication, mowing) Sandy loam or coarser (granitics) Minimum Soil Cover % Loam or finer

9 Prescribed Fire Areas (underburn, hand pile/burn) Sandy loam or coarser (granitics) Loam or finer *Soil cover consists of low growing live vegetation (12 inches high), rock fragments (greater than 1/2 inch in diameter), slash (any size) and fine organic matter (charred or not) that is in contact with the soil surface. Fine organic matter refers to the duff, litter, and twigs less than 3 inches in diameter. 3. FSM 2500, Chapter Soil Management. Soil Stability Indicator: Table 2. Soil Stability Indicator Condition Assessment in FSM Soil Function Support for Plant Growth and Soil Hydrologic Functions Indicator Soil Stability Indicator Condition Good Fair Poor (Partially Meets Desired Condition) (Meets Desired Condition) An adequate level of soil cover is present and signs of erosion are not visible or very limited in degree and extent. Any existing erosion control measures are effective. Generally soil cover level is 50% or greater and is well distributed for soil types capable of supporting this level. For minor portions of the area, soil cover is lacking and/or existing erosion control measures are ineffective and there are signs of erosion such as pedestals, sheet, rill, and/or gully erosion visible. (Does Not Meet Desired Condition) Major portions of the area lack soil cover and/or lack effective erosion control measures. Signs of erosion such as pedestals, sheet, rill, and/or gully erosion are common. Methods Indicator: Change in indicator conditions for soil stability. 8

10 The indicator condition for soil stability was estimated from previous experience in road rehabilitation projects and best available science. For soil stability indicator, the analysis area is bounded by where disturbing activities take place. This includes the approximately 5.8 miles of existing roadbed what will receive treatment. The analysis is further bounded in time by the foreseeable future period during which effects of this project could persist as detectable, significant effects. Soil cover, as it affects soil stability, can recover quickly as needles and other organic debris is deposited on the forest floor. The temporal boundary for soil stability is 5 years. For cumulative effects, the analysis is bounded in time by past, present, and reasonably foreseeable future projects. For the soil resource, cumulative effects are further bounded in space to where ground disturbing activities take place. Effects Analysis No Action There will be no immediate or short-term effect of this alternative on the soils, as soil disturbing activities will not take place. In the short term, soil cover for erosion protection will not change in the project area. Leaving legacy sediment sources untreated will have a long-term negative impact on desired conditions for soil stability and soil organic matter; soil loss is expected to occur when legacy sediment sites such as fill material and landslides fail. Alternative 2 Direct and Indirect Effects Fill removal, re-contour/runoff dispersal, hand treatments, and road clearing during machinery ingress can have short term impacts to soil cover and stability but will provide for long term benefits. Pulling fill will require removing soil and vegetative cover during project activities but soil stability desired condition will be met when slash or much is applied to disturbed sites. Re-shaping of roadbeds to disperse runoff and installing effective erosion control measures will improve desired conditions for soil stability. Hand treatments including installing waterbars will have only minor impacts to soil cover and will also improve desired conditions for soil stability. Road clearing during machinery ingress will leave some sections of rehabilitated roads without soil cover but PDFs require disturbed areas to be covered with slash or mulch if there is a risk of surface erosion. Results from erosion studies on road decommissioning have shown that excavated crossings can be a short-term sediment source the first few years following treatment (Keppeler, 2007). However, by eliminating the risk of stream diversions and culvert failures, road removal treatments significantly reduce long-term sediment production from abandoned roads. 9

11 Cumulative Effects Past actions including timber harvest and mining are evident on the landscape in the project area and are reflected in the discussion of the affected environment. There are reasonably foreseeable future actions that could overlap areas where activities in this project are proposed. Reference Current SOPA. The impact to soil stability of underburning will be minor as PDFs require adequate soil cover to prevent erosion. Non-commercial thinning and pile burning will have only minor impacts to soil stability where the piles are burned but slash and forest for litter elsewhere will prevent erosion. Adding the effects of the no action or the action alternatives to the effects of past, present and reasonable foreseeable future actions is not expected to have measurable effects on soil stability and erosion and, therefore, no significant cumulative effects will occur. Conclusion The soil stability indicator is expected to remain in the Fair to Poor condition in the No Action Alternative. For Alternative 2, the soil stability indicator is expected to improve to Good for all treatment sites. Issue #2- Soil organic matter The organic matter in the soil profile is a major source of ecosystem nutrients that are essential to plant growth. Soil organic matter levels fluctuate naturally over time; soil organic matter on the soil is a balance between inputs from vegetation and decomposition rates as well as natural disturbances such as wildfire. Desired conditions includes amounts and distribution of organic matter present that are within the range of the ecological type and normal fire return interval and limited areas of displacement of the upper soil layers. Rules 1. LRMP S&G 3-1: Plan and implement land management activities to maintain or enhance soil productivity and stability. 2. LRMP S&G 3-3: Maintain soil productivity by retaining organic material on the soil surface and by retaining organic material in the soil profile. 3. LRMP S&G 3-4: A minimum of 50% of the soil surface should be covered by fine organic matter following project implementation, if it is available on the site. 4. LRMP S&G 3-5: Maintain a minimum of 85% of the existing soil organic matter in the top 12 inches of the soil profile to allow for nutrient cycling and maintain soil productivity. 5. FSM 2500, Chapter Soil Management. Surface and Soil Organic Matter Indicator: 10

12 Table 3. Surface Organic Matter and Soil Organic Matter Indicator Condition Assessment in FSM Soil Function Indicator Indicator Condition Good Fair Poor (Partially Meets Desired Condition) (Meets Desired Condition) (Does Not Meet Desired Condition) Support for Plant Growth Soil Organic Matter (SOM) The thickness and color of the upper soil layer is within the normal range of characteristics for the site and is distributed normally across the area. Localized areas of displacement may have occurred but it will not affect the productivity for the desired plant species. For minor portions of the area, the upper soil layer has been displaced or removed to a depth and area large enough to affect productivity for the desired plant species. Generally an area will be considered displaced if more than one-half of the upper soil layer or 4 inches (whichever is less) is removed from a contiguous area larger than 100 sq. ft. Major portions of the area have had the upper soil layer displaced or removed to a depth and area large enough to affect productivity for the desired plant species. Method Indicator: Change in indicator conditions for soil organic matter. The indicator condition for soil organic matter was estimated from previous experience in road rehabilitation projects and best available science. For soil organic matter indicator, the analysis area is bounded by where disturbing activities take place. This includes the approximately 5.8 miles of existing roadbed what will receive treatment. The analysis is further bounded in time by the foreseeable future period during which effects of this project could persist as detectable, significant effects. Soil organic matter can take years to decades to rebuild after it is lost through displacement or erosion. The temporal boundary for surface and soil organic matter is 30 years. For cumulative effects, the analysis is bounded in time by past, present, and reasonably foreseeable future projects. For the soil resource, cumulative effects are further bounded in space to where ground disturbing activities take place. 11

13 Effects Analysis No Action There will be no immediate or short-term effect of this alternative on the soils, as soil disturbing activities will not take place. Leaving legacy sediment sources untreated will have a long-term negative impact on desired conditions for soil stability and soil organic matter; soil loss is expected to occur when legacy sediment sites such as fill material and landslides fail. Alternative 2 Direct/Indirect Fill removal, re-contour/runoff dispersal, hand treatments, and road clearing during machinery ingress will cause some displacement of soil organic matter which is necessary to complete rehabilitation objectives. Pulling fill will require removing soil from channels, swales, and roadbed failures to be placed in a more stable location. Relocating the fills to a more stable location, reshaping roadbeds to disperse runoff, and installing waterbars will improve desired conditions for soil organic matter by reducing soil loss by erosion. Road clearing during machinery ingress will cause some soil displacement as some roadbeds are cleared and leveled to allow the safe travel of equipment. Decommissioning can also have short-term impacts as sediment is released by erosion andchannel adjustments in the immediate post-decommissioning period (Switalski, et al., 2004; Keppler, et al., 2007). Proper design and PDFS can be employed to minimize post-treatment channel adjustments and sediment delivery Cumulative Effects Past actions including timber harvest and mining are evident on the landscape in the project area and are reflected in the discussion of the affected environment. There are reasonably foreseeable future actions that could overlap areas where activities in this project are proposed. Reference current SOPA. These activities will have no impact to soil organic matter as all proposed work will be done by hand. Adding the effects of the no action or the action alternatives to the effects of past, present and reasonable foreseeable future actions is not expected to have measurable effects on soil organic matter and, therefore, no significant cumulative effects will occur. Conclusion The soil organic matter indicator is expected to remain in the Fair to Poor condition in the No Action Alternative. For Alternative 2, the soil organic matter indicator is expected remain in the Fair condition on sections of the roadbeds where large cut and fill slopes have displaced topsoil. Sites where erosion control and fill stabilization occur will improve to a Good condition because the risk of topsoil loss by erosion will be greatly reduced. 12

14 Issue #3- Soil Structure Changes in soil structure result in densification and distortion of the soil where biological activity, porosity and permeability are reduced. Destruction of soil structure can reduce water infiltration rates, have higher or lower water holding capacity (depending on soil texture), have an increase in soil strength that restricts root growth, and have an increase in soil erosion risk by accelerated run-off. Desired conditions include soil strength levels that are conductive to favorable rooting environment and soil structure and macroporosity that are relatively unchanged from natural conditions. Rules 1. LRMP S&G 3-1: Plan and implement land management activities to maintain or enhance soil productivity and stability. 2. FSM 2500, Chapter Soil Management. Soil Strength and Structure Indicators: Table 4. Soil Strength and Structure Indicator Condition Assessment in FSM Soil Function Soil Hydrologic Function Indicator Soil Structure and Macroporosity Indicator Condition Good Fair Poor (Partially Meets Desired Condition) (Meets Desired Condition) Visually soil structure and macro-porosity (defined here as pores 1mm or larger) are relatively unchanged from natural condition for nearly all the area. Signs of erosion or overland flow are absent or very limited in degree and extent. Infiltration and permeability capacity of the soil is sufficient for the local climate. For minor portions of the area: soil structure and macro-porosity are changed; or platy structure and/or increased density evident; or overland flow and signs of erosion are visible. Infiltration and permeability capacity is insufficient in localized portions of the area. (Does Not Meet Desired Condition) Major portions of the area have reduced infiltration and permeability capacity indicated by soil structure and macro-porosity changes; or platy structure and/or increased density; or signs of overland flow and erosion. 13

15 Method Indicator: Change in indicator conditions for soil structure. The indicator condition for soil structure was estimated from previous experience in road rehabilitation projects and best available science. For soil structure indicator, the analysis area is bounded by where disturbing activities take place. This includes the approximately 5.8 miles of existing roadbed what will receive treatment. The analysis is further bounded in time by the foreseeable future period during which effects of this project could persist as detectable, significant effects. Once compacted, soil strength, structure, and macroporosity can remain affected for decades. The temporal boundary for soil structure is 30 years. For cumulative effects, the analysis is bounded in time by past, present, and reasonably foreseeable future projects. For the soil resource, cumulative effects are further bounded in space to where ground disturbing activities take place. Effects Analysis No Action Direct effects of the No Action alternative would be of no effect on the soils, as soil disturbing project activities would not take place. Soil Strength and structure conditions would remain the same in the shortterm, with very slow long-term natural recovery of old roadbeds. There would be no indirect or cumulative effects of the No Action alternative. Alternatives 2 Direct/Indirect The proposed actions will take place on existing roadbeds which do not currently meet desired conditions for soil structure and macro-porosity. Over the past few decades, soil structure and macro-porosity have recovered to a minor extent on some of the roadbeds. Allowing machinery to travel on these roadbeds will reset the recovery process. WWOs require that work will be done during dry soil conditions which will help limit addition compaction on the roadbeds. It is expected that over the long term natural process will reduce soil compaction. To ensure the roadbeds are allowed to recover after project completion, access from system roads will be blocked from vehicle traffic. Where conditions allow, roadbeds will be ripped to decrease compaction and increase infiltration. Ripping is only feasible where rock content is less than 35% by volume and slopes are less than 20%. Studies on road ripping have been shown to reduce erosion, improve infiltration, and increase the rate of revegetation (Switalski, 2004) 14

16 Cumulative Effects Past actions including timber harvest and mining are evident on the landscape in the project area and are reflected in the discussion of the affected environment. There are reasonably foreseeable future actions that could overlap areas where activities in this project are proposed. Reference current SOPA. These activities will have no impact to soil structure and macro-porosity as all proposed work will be done by hand. Adding the effects of the no action or the action alternatives to the effects of past, present and reasonable foreseeable future actions is not expected to have measurable effects on soil structure and macro-porosity and erosion and, therefore, no significant cumulative effects will occur. Conclusion The soil structure indicator is expected to remain in the Fair to Poor condition in the No Action Alternative. For Alternative 2, the soil structure indicator is expected remain in the Fair condition on sections of the roadbeds where ripping is not possible due to high rock content or steep slopes. At sites where ripping occurs, the soil structure condition will improve to a Good as infiltration and permeability recover to near undisturbed levels. Compliance with Law, Policy, and Regulation Table 5. Compliance with Law, Policy, and Regulation Resource Issue Soil Cover, Surface and Soil Organic Matter, Soil Strength and Structure Soil Cover Surface and Soil Organic Matter Law, Policy or Regulation (including S&G) LRMP S&G 3-1: Plan and implement land management activities to maintain or enhance soil productivity and stability. LRMP S&G 3-2: With the exception of roads, permanent facilities or other projects that will permanently occupy a site, the following levels of total soil cover should be maintained at the stand level to reduce the potential of soil erosion LRMP S&G 3-3: Maintain soil productivity by retaining organic material on the soil surface and by retaining No Action Alternatives 2, 3, and 4 Complies Complies Complies Complies Complies Complies 15

17 organic material in the soil profile. Surface and Soil Organic Matter LRMP S&G 3-4: A minimum of 50% of the soil surface should be covered by fine organic matter following project implementation, if it is available on the site. Complies Complies Surface and Soil Organic Matter LRMP S&G 3-5: Maintain a minimum of 85% of the existing soil organic matter in the top 12 inches of the soil profile to allow for nutrient cycling and maintain soil productivity. Complies Complies Literature Cited 16

18 Foster, C.M. and G.K. Lang Soil Survey of Klamath National Forest area, California, parts of Siskiyou County, California and Jackson County, Oregon. USDA-Forest Service, Pacific SW Region, Vallejo, California. Keppeler, Elizabeth T., Cafferata, Peter H., and Baxter,William T., 2007 STATE FOREST ROAD 600: A RIPARIAN ROAD DECOMMISSIONING CASE STUDY IN JACKSON DEMONSTRATION STATE FOREST. California Forestry Note 120. June Powers, R., Scott, D., Sanchez, F., Voldseth, R., Page-Dumroese, D., Elioff, J., and Stone, D The North American long-term soil productivity experiment: findings from the first decade of research. Forest Ecology and Management, 220: Switalski, T. A, Bissonette, J. A., DeLuca, T. H., Luce C. H., and Madej, M. A., Benefits and impacts of road removal. Front Ecol Environ; 2(1): USDA Forest Service, Soil erosion hazard rating. Soil and Water Conservation Handbook, Ch. 50, R-5 FSH , R5 Amend. 2. PSW Region, Vallejo, California USDA Forest Service, Klamath National Forest s Land and Resource Management Plan, Capter 4. USDA-Forest Service, PSW Region, Klamath National Forest, Yreka, California. USDA Forest Service, R5 Supplement to FSM Soil Management. USDA-Forest Service, Pacific SW Region, Vallejo, California.10p. Appendices Appendix A. Soil Map and Interpretations for the Project Area 17

19 Figure 1. Order 3 Soil Survey Map of the Project Area Table 6. Proposed Treatments and Soil Map Units 18

20 Roadbed ID# Treated Roadbed length (miles) Length Treated with Heavy Machinery (miles) Legacy Sites Treated NFTS Road Maintenance (miles) Proposed Treatments Soil Map Units (SMU) 46N NA 46N50.3 W NA Fill Removal; Recontour/Runoff Dispersal Fill Removal; Recontour/Runoff Dispersal 46N50.3E 0.2 NA 3 NA Hand Treatments 46N50.4 (access to 46N50.3) NA Re-contour/Runoff Dispersal 46N NA Re-contour/Runoff Dispersal 46N Re-contour/Runoff Dispersal ,141 46N N17Y N25Y Fill Removal; Recontour/Runoff Dispersal Fill Removal; Recontour/Runoff Dispersal Culvert and Fill Removal; Re-contour/Runoff Dispersal ,183 47N NA 2 NA Hand Treatments N NA 48N20.1A NA Fill Removal; Recontour/Runoff Dispersal Fill Removal; Recontour/Runoff Dispersal 157, N NA 48N NA Fill Removal; Recontour/Runoff Dispersal Fill Removal; Recontour/Runoff Dispersal 48N20.5A NA Re-contour/Runoff Dispersal , N20.5B NA Re-contour/Runoff Dispersal 48N NA Re-contour/Runoff Dispersal Totals Table 7. Soil Survey Information for the Project Area 19

21 SMU SMU Name Parent Material Clallam, deep-holland families assn., 30 to 70 % residuum weathered from 113 slopes metamorphic rock Clallam family, very deep- Riverwash assn., 0 to 15 % residuum weathered from 115 slopes metamorphic rock Holland-Clallam, deep- Coboc families assn.s, 15 to 70 % slopes Holland-Skalan families assn., 15 to 30 % slopes Lithic ruptic-xerochreptic haploxeralfs-olete family assn., 30 to 90 % slopes Olete family-lithic ruptic- Xerochreptic haploxeralfs assn., 30 to 90 % slopes Parks family-lithic ruptic- Xerochreptic haploxeralfs assn., 30 to 90 % slopes Skalan-Clallam,deep-Decry families assn., 15 to 70 % slopes Surface Texture Soil Depth (in) Soil Productivit y Rating Subsoil Potential very gravelly loam 107 M Y very gravelly sandy loam 201 M Y residuum weathered from igneous and metamorphic rock gravelly loam 152 M Y residuum weathered from igneous and metamorphic rock gravelly loam 152 H Y residuum weathered from peridotite residuum weathered from ultramafic rock residuum weathered from ultramafic rock residuum weathered from igneous and metamorphic rock very gravelly loam 43 L N very gravelly loam 152 M N gravelly fine sandy loam 94 L N very gravelly loam 81 M Y 20

22 Table 8. Soil erosion hazard rating (EHR) for the soils in the Project Area SMU Map Unit Name Post-Trtmt Soil Cover Recommendation Erosion Hazard Rating Current Post- Trtmt Bare Clallam, deep-holland families assn., 30 to 70 % slopes 50-70% L M H Clallam family, very deep- Riverwash assn., 0 to 15 % slopes 50-70% L L L Holland-Clallam, deep- Coboc families assn.s, 15 to 70 % slopes 50-70% L M H Holland-Skalan families assn., 15 to 30 % slopes 50-70% L M H Lithic ruptic-xerochreptic haploxeralfs-olete family assn., 30 to 90 % slopes 50-70% M M VH Olete family-lithic ruptic- Xerochreptic haploxeralfs assn., 30 to 90 % slopes 50-70% M M VH Parks family-lithic ruptic- Xerochreptic haploxeralfs assn., 30 to 90 % slopes 50-70% M M VH 183 Skalan-Clallam,deep-Decry families assn., 15 to 70 % slopes 50-70% L M H The Region 5 Erosion Hazard Rating System was used to generate ratings (USDA Forest Service, 1990). 21