soil impacts report -...

SOIL IMPACTS REPORT

For the

Tracy Placer Mining Project

Prepared By:

JAMES G. ARCHULETA Soil Scientist

For the DRAFT EIS

March 10, 2008

TRACY PLACER SOIL IMPACTS REPORT

INTRODUCTION The proposed Tracy Placer Mining Project is located in the Sucker Creek watershed, which is part of the Rogue River basin. Sucker Creek flows into the East Fork Illinois River 2 miles south of Cave Junction and then into the Illinois River before joining with the Rogue River at Agness. The proposed mine activity area is located inside the riparian zone of Sucker Creek and it also includes 2 small tributaries to Sucker Creek: Cedar Gulch and an un-named creek. Placer mining began in the Sucker Creek channel in 1853. The proposed mine site has been previously mined and so the site’s soil profile has undergone substantial alteration. There are large piles of boulders from early mining on both sides of the stream. Vegetation has since re-established and is dominated by a conifer forest. This report evaluates the claimant’s proposed Plan of Operations (PoO) as well as a modified version of the proposed plan: the Forest Service Alternative. The Forest Service alternative, Alternative 2, contains specific measures for the sequence of mining operations, access, stream crossing requirements and reclamation that would serve to minimize surface resource impacts. Field information in this report is based upon a site visit conducted on June 12, 2006. Mitigation measures and management practices identified in this report were created during interdisciplinary team (IDT) meetings held in the office and field. SUMMARY OF PROPOSED MINING ACTIVITIES Mr. Clifford R. Tracy, the claimant and mine proponent, proposes to mine approximately 5 acres of an alluvial terrace that is adjacent to Sucker Creek. Operations would extend over a 2 to 5 year period. To carry out the proposed mine project, operations would require the use of heavy earth-moving equipment, removal of all vegetation, diversion and use of water from a small creek named Cedar Gulch and deep disturbance of the placer deposit. Mining of the placer would be conducted at the site in 2 phases, with work beginning in the northwestern portion of the mine activity area. Cedar Gulch is roughly the demarcation between the two phases. Figure 1 is a locality map displaying the claim boundary, mine access road (as it currently exists), mine activity area and associated features for the miner’s proposal (the Proposed Action). The miner would remove all trees from the mine site using chain saws and heavy equipment (crawler dozer, tracked excavator and dump trucks). The trunks of large felled trees would be stacked separately from slash, small-diameter material and stumps. Stumps would be pushed or pulled out by a crawler dozer or tracked excavator. Some logs and other removed materials would be set aside (that is, not sold or otherwise used by the Forest Service) for use in site reclamation. During mining, terrace materials would be excavated down to bedrock. In addition, the miner proposes to excavate through approximately 250-feet of the Cedar Gulch channel and approx-imately 250-feet of the un-named creek channel. These creeks would be diverted into temporary channels when the existing channels are mined. Water from Cedar Gulch would be used during mine operations to separate gold from its substrate (wet processing). Placer excavations would likely segregate existing alluvial/colluvial materials into fines and coarse rock rubble.

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Figure 1. Locality map (orthographic aerial photograph base) displaying the claim boundary, mine access road (as it currently exists), mine activity area and associated features for the Proposed Action. Worthy of note here is that Figure 1 shows the approximate location of the Cedar Gulch and un-named creek channels within the mine activity area. These depictions of the creek channels accurately show the actual confluences with Sucker Creek and they are more representative of the creek channel locations than the creek locations shown on published topographic maps. The IDT speculates that the present creek channels are not the original channels and the present locations are the result of past mining operations. Following completion of mining in the phase 1 area, the site would be reclaimed prior to com-mencement of clearing and mining on the second portion of the mine activity area. A full and detailed description of mining and reclamation activities, by alternative, is available in the envi-ronmental impact statement (EIS) that has been prepared in response to claimant’s proposal.


CURRENT CONDITIONS AND PROCESSES Soils at the Mine Site The hill slopes above the mine activity area are included in soil map unit 48F, a Josephine Series gravelly loam, as typed by the Soil Conservation Service (Borine 1983). A thorough description of the Josephine Series (USDA NRCS 2000) is included as Attachment A at the end of this report. The area extent of map unit 48F, in relation to the mine, is displayed in Figure 2. Due to historical mining, however, soil map unit 48F does not accurately depict soils as they exist in the mine activity area. Within the alluvial terrace where the mine is proposed, piling and sorting of placer materials during previous mining have created a collection of differing soil profiles that very greatly in the space of a few feet. On the east side of Cedar Gulch, soils in low places are a wet very fine sandy loam and slightly raised areas are a well-drained sandy loam. On the west side of Cedar Gulch, the soils range from a well-drained sandy loam to piles of loose cobbles and stones (see Attachment B for definitions of textures and particle sizes).


Indeed, in his soil survey of Jose-phine County, Borine (1983) identi-fies stream terraces affected by past placer mining as “Dumps” (soil map unit 30). The soil survey explains: “Dumps consists [sic] of mine tailings that are mainly on flood plains. The dumps were formed when excavated material was deposited after the valuable minerals had been removed. … Dumps consists [sic] mostly of cobbles and pebbles. The finer material has been removed during mining operations. The surface ranges from nearly level to hummocky. Included in this unit are small areas of sandy loam. Permeability of Dumps is very rapid. A seasonal high water table occurs in winter and spring.”

Figure 2. NRCS soil mapping units for the area surrounding the proposed Tracy mine site. The proposed mine activity area, drawn in red, is an approximate location and does not include the entire activity area. The activity area is fully within mapping unit 48F, Josephine gravelly loam (USDA NRCS 2007).

The piles of rock rubble cover an area encompassing about 1/3 (approximately 1.6 acres) of the proposed mine activity area. The piles of gravels, cobbles and stones are unsuitable for planting trees, and not just because of the physical difficulty of planting. According to Coonce (1991), unsuitable in this context means that planted seedlings (if seedlings could be planted) may not survive because of:

• An excessive amount of air voids between rocks. • A gravel layer where there is little or no fine soil material or >80 % by volume of small

size rock fragments (predominately 1/12 to 3/4 inch dia.) that reaches to a depth of >10 inches with <20 percent fine soil material.

The depth to bedrock among the rock piles is unpredictable, largely due to rolling and uneven placement of mine rock waste (soil, cobbles and stones) that resulted from historical mining operations. And while soil, sands and other fine materials are not visible at the surface of the cobble piles, large trees growing throughout the placer terrace offer evidence that soil must be present at a shallow depth below the ground surface. As can be seen in Figure 3, tall Douglas-fir trees dominate the mine site. These existing trees indicate the site’s considerable ability to absorb previous impacts from exploitive use and that past manipulation of the site by mining did not cause permanent or irreversible harm to soils (as a growth medium). However, productivity was proba-bly reduced compared to original conditions.

Figure 3. Photograph showing the rocky substrate of the mine site and the existing trees growing in the area. The photograph was taken in the northwest portion of the proposed mine site.

Erosion Potential of the Existing Surface Materials Surface soil erosion is a natural, on-going process that is a consequence of gravity combined with transport provided by rainfall and/or wind. Rates of erosion are determined by soil texture, vegeta-tion, steepness of slope and climate. In undisturbed forested landscapes, erosive forces transport materials short distances but particles then become trapped behind woody material and stabilized by vegetation, sometimes for hundreds of years. The Tracy Placer mine site should not be considered undisturbed and therefore any erosion that is occurring is likely somewhat accelerated (i.e. in excess of natural rates). Currently, though, there is little to no sign of active surface erosion (outside of stream channels) due to the high proportion of cobble, stones and boulders in the terrace deposit. Early-day hydraulic mining probably flushed quantities of fine silts and sands out of the placer terrace.



Existing Site Productivity Site productivity is the inherent quality of a site to produce or provide the commodities or values for which the area will be managed. In its strictest use, site productivity is a quantitative estimate of the potential for a discrete and homogenous land area to produce plant biomass (or net primary production) (Skovsgaard and Vanclay 2008). As a rooting medium for higher plants, soil furnishes water, structural support, nutrients, gas exchange and soil biota that are essential for primary plant production. The soil variables that collectively define site productivity, and how each variable is influenced by external impacts, are displayed in Table 1.

Table 1. Soil variables and how the variable may be influenced within its environment.

Soil Variable Impacts that can Potentially Influence the Soil Variable Soil depth & rooting zone Erosion rate can influence, compaction can influence rooting zone Soil structure & texture Compaction can change both structure and texture Infiltration rate Compaction can reduce infiltration Water holding capacity (WHC) Organic matter = WHC; compaction can increase WHC1

Nutrient supply and cycling Availability of humus, litter and woody debris (organic matter) Site productivity is often quantified as an index for forest management purposes and site indices are most commonly based on measurements of vegetative growth. Site index (SI), which is a measure of stand mean height at a given age for a particular tree species, is the most commonly used surrogate for expressing site productivity in forestry. However, geocentric (earth-based) methods are used to classify site productivity, as well (Skovsgaard and Vanclay 2008). My observations of the mine site indicate soil depths are uneven and may vary from shallow to deep. Moreover, there is often no soil visible at the surface and finer particles are often buried beneath gravels, cobbles and stones. In addition, coarse rock fragment content of the terrace substrate is generally high. Therefore, the site is believed to have a lowered productivity in comparison to pre-mining conditions (Brady and Weil 1999, Rodrigue and Burger 2004). The large percentage of coarse fragments is likely detrimental to SI, which typically declines as coarse fragment proportions increase (Sandusky 1980, Rodrigue and Burger 2004). Medium to coarse pores (voids between rocks and soil particles) undoubtedly increase water drainage and influence gas exchange in the soil (Brady and Weil, 1999). It is thus reasonable to presume the combination of high coarse fragments and excess voids make these well-drained mine soils droughty during dry periods, impairs gas exchange and decreases nutrient availability (Thurman and Sencindiver 1986). However, despite the obvious visual cues that suggest impairment of site productivity, large trees that are of value to the riparian environment are present within the proposed activity area and are growing well. The presence of these trees is a testament to resilience of the soil at the mine site to long-lasting productivity loss. The apparent resilience of this soil, as evidenced by the cover of large trees on the site (Figure 3), implies that any previous impairment (damage) caused to the terrace substrate was not permanent or irreversible insofar as tree colonization is concerned. Since this site has not been irreversibly damaged from past activities, reclamation requirements of the LRMP (page IV- 55, Minerals 10-7, 1a. 1b. & 1c) should be attainable. However, the success 1 Condition may be beneficial to moisture holding capacities in some sandy textures (Powers et al. 2005)

of reclaiming the site for growing trees would largely depend upon the deliberate actions taken to retain fine materials near the surface and to replenish organic matter. Active reclamation of the site should decrease the time needed for forest tree recovery following mining, which could be extended much longer without active reclamation. Regardless of the efforts to reclaim the mine site, with every mining entry, some level of site productivity may be lost due to the nature of placer mining activities. PRACTICES for PROTECTING SOILS and SITE RECLAMATION The discussion on practices and standards in this section focuses on the measures to be included in Alternative 2. Figure 4 shows the major features associated with mine operations as they would be implemented in Alternative 2. These features are described in detail in the EIS.

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Figure 4. Site plan map illustrating in detail the claim boundary, mine activity area, bridge site, tractor trail, slash/log disposal areas and other features associated with Alternative 2.



Mr. Tracy proposed broad ideas or practices for mine site reclamation and revegetation in his submitted plan of operations (Alternative 1) but identified only boulder placement and re-contouring as specific mitigation/reclamation measures he would use. Because EIS Alternative 1, the Proposed Action, is Mr. Tracy’s proposal for mining operations, practices and standards for mitigating soils impacts in Alternative 1 are those that he included in his plan of operations. In Alternative 2, the Forest Service proposes supplementary standards and measures aimed at minimizing soils damage during mining operations and for completing reclamation and site revegetation (as provided in the Siskiyou National Forest LRMP, Minerals Standard 10-7, 1a, 1b, and 1c) after mining. As depicted in Figure 4, the slash/log storage areas are disposal sites where trees and vegetation cleared from the mine activity area would be deposited, so that the mine site is free of vegetative clutter and debris. In the storage areas, most trees are likely to be cut down and stacked to make room for the debris generated from the mine site itself. However, no excavations would occur within the storage areas and so ground disturbance would be limited to surficial damage caused by moving logs and debris into the area. On the other hand, the mine activity area would be fully excavated down to bedrock (in both Alternative 1 and Alternative 2) and so substrate materials there are likely to be completely re-sorted and remixed. In addition, a holding pond would be used in the gold separation process and this pond would be progressively shifted across the mine site as materials are dug from one end of the pond and dumped on the other end. What follows are descriptions of reasonable, operationally feasible measures and objectives that would be implemented to protect soils and to reclaim the mined site in Alternative 2. Heavy Equipment Use A crawler dozer, tracked excavator and dump trucks would be used in bridge construction, site clearing and to excavate and process substrate materials within the mine activity area. However, soil compaction created by equipment are not of concern throughout the operations area generally because of the high rock fragment content within the placer terrace. Gravels, cobbles and stones are by volume a substantial proportion of the alluvial deposits that cover the mine site and adjacent areas. Therefore, detrimental increases in bulk density or decreases in soil porosity are not ex-pected because of the inherent rockiness of the site. Moreover, where soils are continually wet because of the surface water that occurs within the mine site (e.g., Cedar Gulch, the un-named creek, etc.), the water would be put into a temporary channel and so excavation work would be conducted without excessive soil saturation. All in all, direct damage to the terrace substrate from compaction is not anticipated. Nonetheless, porous soils, water on the site and the proximity of Sucker Creek and other streams to the mine excavations makes the site susceptible to injury from contamination by fuels, lubricants or other machine fluids. Therefore, spill avoidance is a top priority. The use of fuels, lubricants and other machine fluids, which are likely to be used in substantial quantities, compels several practices and requirements to avoid site contamination. The objectives of these practices and requirements are to 1), protect on-site soils (and water) against contamination by petroleum products and other machine fluids, and 2), to maintain natural features (such as the stream-side buffers) as barriers to movement of contaminants, should a spill occur.


Heavy Equipment Practices and Requirements: • Equipment shall be prohibited from entering the stream-side buffer along Sucker Creek,

except for ingress and egress to the mine site on designated routes. • Dump trucks, heavy equipment and dredging apparatus could be left on site within the

claim area during the seasonal annual shutdown period, if requested and with explicit ap-proval from the Forest Service. Approval for over-winter storage would be obtained an-nually in the fall each year and would be conditioned on using storage specifications mu-tually determined by the Forest Service and the operator for safeguarding the environment. One requirement of on-site storage shall be that all heavy equipment and dredging appara-tus is moved to and stored on the 4612 side of Sucker Creek.

Handling and Storage of Fuel, Lubricants and other Machine Fluids:

• Prepare a Spill Prevention, Containment and Cleanup Plan as required by the Oregon De-partment of Environmental Quality.

• Fuel and lubricants storage must meet State standards for minimum distance from a stream. • Store fuel drums in an upright position to prevent the possibility of spills and leaks. • Fill fuel tanks and change all machine fluids (anti-freeze, hydraulic fluid, transmission oil,

etc.) in fueling areas designated by Forest Service. • All fuel, liquid lubricant and anti-freeze containers, drums or tanks that are temporarily

stored on site shall be placed inside of a spill catchment device (such as an Enpac “Spill-pal®”) constructed of material impervious to petroleum products and that is of sufficient size to accommodate at least 50 percent of the total quantity of stored liquids.

• During fueling or machine fluid changes, a spill catchment device shall be placed under the machine to provide containment of incidental spills.

• On-site absorbent materials will be kept on hand adjacent to storage facilities. The absor-bent material will be either 1) a commercially available petroleum product absorbent ma-terial, or 2), any alternative material acceptable to the Forest Service and State that is capa-ble of absorbing spilled petroleum products.

• Fuel spills must be immediately contained, cleaned up and reported to the Forest Service. Final Mine Site Reclamation Reclamation is the procedure used to make land suitable for future use where a mine had been. Most land disturbed by placer operations can successfully revegetate as long as the area is left within a reasonable range of conditions. However, soil is scarce at the ground surface presently and, because of the mining method proposed, much fine-textured material that is excavated is expected to settle toward bedrock and coarser material is likely to dominate the land surface after gold processing. In fact, the ability to collect, segregate and retain fine-textured site materials is likely to be limited, overall. Moreover, the quality of saved soil materials for placement at the ground surface is not likely to be high, either, because availability of nutrients and organics within saved materials may be compromised, as well. There is widespread acceptance that placing locally-obtained soils at or near the land surface on reclaimed mine lands is fundamental for restoration of those lands. Fine-textured materials that are spread on the surface of reclaimed lands benefits vegetative recovery by improving water infiltra-tion, promoting plant rooting, enhancing nutrient cycling and by providing a potential source of plant propagules, which can perpetuate a native plant community (Bowen et al. 2005). Rodrigue (2004) identified four soil properties fundamentally important to trees for good growth in mine reclamation projects: ample rooting media, proper aeration, adequate moisture retention and

nutrient availability. Thus, it is important to provide for these soil factors and properties by using materials obtained from the existing site when reclaiming mined land. Notably, too, the usual droughtiness of highly porous mine substrates can be offset somewhat by providing an adequate depth of soil at the land’s surface (Wade et al. 1985, Sencindiver and Smith 1978). While Figure 3 above shows that mature conifers occupy the existing site, the visible cobbles and stones in the photo also reveal the lack of surface soil presently in much of the area west of Cedar Gulch. Water availability, which is related to the proportion of fine-sized soil materials, is the most important growth-promoting factor for many native forest types (Pritchett and Fisher 1987) and is particularly vital on reclaimed mine sites (McFee et al. 1981, Czapowskyj 1978). To achieve reclamation of the site, retention of finer site materials (that are texturally considered “soil”) is needed for use in the reconstruction of a stratified soil profile. Segregation and stockpil-ing of these types of materials during normal operations would aid in site reclamation later. The direction provided at LRMP Standard 10-7 (1a), (1b) and (1c) offers general guidance on mining reclamation objectives. Illustrated below are soil profiles for the mine site as hypothesized to currently exist and as desired once reclamation is complete. The stratified layers of each profile, in order from the ground surface to bedrock (R), are depicted in Figure 5. The desired reclamation profile is shown on the right side of the illustration.

O layer: Materials for this layer are some portion of the slash and other organic debris created from land clearing activities. The depth of this layer shall not exceed fuel loading recommendation of fuels specialist. Topsoil (Reclaimed): fine textured mined spoils. Materials shall be obtained from mine materials being processed. Buried Slash Layer: Materials used for this layer are some portion of the slash and other organic debris that would be created from land clearing. Materials for this layer can be deposited to < 3 feet deep, when mixed and compacted with rock/soil. Organic matter, if not in excess (such as in peaty soils), typically improves soil physical condition. Displaced Rock (Mining Spoils) and Mixed Soil Layer: Cobbles, stones, boulders and fine-textured materials deposited and layered mostly as a direct result of mine excavation and gold processing within the holding pond.

Figure 5. Depictions of hypothesized current soil profile and the desired soil profile. The illustrations are not to scale; these depictions are meant to display specific layers in the soil mitigations.

R Layer: The bedrock layer, is not expected to be disturbed during the mining process.



I anticipate the desired soil profile can be achieved generally across much of the mined area. Since fine-sized materials are likely to be limited in quantity, though, the priority for use of this material would be along both banks of Cedar Gulch and the unnamed tributary. Elsewhere, coarser mate-rials may substitute for “topsoil” as the covering over the buried organic debris that is mixed together with available placer terrace materials. Where the depth of fine-sized materials (with a sandy loam texture) is at least 10 inches thick on the surface, successful plant colonization is expected to occur readily (Bowen et al. 2005, Machulla et al. 2005). Organic matter tends to improve the water-holding capacity and nutrient relationships of sandy soils (Ashby and Vogel 1994) as well as in loam soils. Therefore, incorporation of woody debris and slash (created during land clearing) into the top three feet of the terrace profile would aid in developing an organic component within the terrace as buried materials decompose over time. While a soil amendment application (fertilizers and/or other materials) can improve short-term soil productivity, the cost of transport and application is sometimes difficult to justify based on the realized long-term soil quality improvement (Banderfelt et al. 2001). Therefore, no soil amend-ment applications are prescribed for reclamation of the Tracy mine site. Following each mine operations phase, then, reclamation would consist of several steps. First, the activity area would be smoothed and re-contoured to leave an elevated terrace along Sucker Creek (this terrace would in many places be well above a height that could be inundated by even a 100-year frequency flood). As part of the grading process, as much as 30 percent of the limbs, treetops, bark (slash) and stumps originally removed from the site should be incorporated (that is, buried and backfilled) into the upper three feet of the waste rock as the area is re-contoured. Next, to the degree that sand, soil or other fine earthen materials are stockpiled and available, these should be spread over the top of coarser rock materials, especially adjacent to streams. To encourage plant growth along the banks of Cedar Gulch and the unnamed creek, fine-sized soil materials as are available should be prioritized first for placement next to these waterways. Focusing the spread of fine materials next to these two creeks ensures the topsoil that is available would be used where planting of trees and shrubs is of highest precedence. It is anticipated that the some of the processed mine aggregates can be recovered and withheld in stockpiles to provide loamy soil. A mixture of clay (~10-30%), silt (~30-50%), and sand (~25-50%) is considered to be a loam soil (USDA 1993). Loam soil is considered the most desirable rooting medium for many kinds of trees (Ashby and Vogel 1994). See Table 1 in Attachment A for particle size classes for sand, silt and clay. No catchments, depressions, ponds or other impoundments capable of holding water would remain on the general terrace surface following reclamation. Cedar Gulch would be reconnected with Sucker Creek diagonally northwest through the phase 1 area, meeting with Sucker Creek approx-imately 400 to 500 feet downstream from the current confluence. No native or non-native grass/forb seeding would occur anywhere on the mine site; however, planting of at least 100 specified native hardwood and/or conifer species (Oregon ash, cottonwood, Port-Orford-cedar, willow, etc.) would be required along Cedar Gulch and the un-named creek (split in roughly equal proportions). Finally, after re-contouring and spreading of topsoil is completed, tree boles (logs) (at least 10 per acre) previously designated for reclamation use would be placed on top of the disturbed area. These logs, each having a minimum length of 35 feet, would be well-distributed across the ground


surface in a natural-appearing, minimal-depth arrangement. Two or three logs may be grouped together, or they may be arranged singly, but a uniform, evenly-spaced distribution is not essential. Other removed vegetative debris, which was piled in disposal areas, may also be distributed across the ground surface, as available. Seasonal Suspension of Mine Operations Included in Alternative 2 is an annual winter shutdown period when no active mining would occur. During the late fall, winter and early spring, the mine site typically receives snow periodically and soils become saturated. To avoid excessive damage to the 058 road and to reduce the potential for erosion and sedimentation, cessation of work is scheduled between November 15 and May 15 each year. Prior to the annual shutdown, the following measures are required:

• The operator shall ensure that exposed slope faces, stock piles and stripped overburden, which are located such that sediments could be deposited directly into water courses, are secured to prevent soil erosion, slumping and subsidence. Any combination of weed free mulches, soil binders or control structures (for example, silt fences, wattles, rice straw bales, jute matting, EcoBlanket®, etc.) may be used to stabilize soil and minimize erosion or sediment delivery to streams.

• The operator shall ensure that drainage on road 058 is secure and capable of diverting win-ter flows from the running surface.

• All camping equipment and supplies shall be completely removed from the claim. IMPACTS ANALYSIS FOR SOILS Erosion Erosion is the detachment and wearing away of soil or rock by water, wind, ice or gravity. Flow-ing water is typically the chief agent of surface erosion in a forest setting. The latent energy needed to foster erosive movement comes primarily from water interacting with gravity. Within the proposed mine activity area, though, coarse rock fragments and the stony content of the placer deposit provides an inherently lower potential for surface erosion because large particles do not easily move. Moreover, the surface slope of the deposit is gentle and the overall terrain is appro-priately identified as a streamside bench with little gradient generally. Nonetheless, at the scale of a few tens of feet, there are presently some steepened pitches within the hummocky terrain of the terrace. These small-scale surface irregularities are likely to persist during mining operations or new piles of rock rubble would be created in their places that have steepened sides. Therefore, in combination with complete vegetation removal and almost com-plete surface disturbance across the mine site, short steep inclines created by piled terrace materials or excavation cuts are likely to create conditions for erosion to occur. Alternative 1 and Alternative 2: For the two action alternatives, the key ground-disturbing actions are nearly indistinguishable and so effects related to erosion would be fundamentally the same. Mine site clearing for either alternative would result immediately in removal of all vegetation on approximately 2.5 acres (during each operating phase) and almost concurrently would cause surface disturbance over the entire activity area (including slash/log storage areas). Then, during mining operations, overbur-den of soil and loose rocks, including areas underlying two small stream channels, would be


excavated down to bedrock across the mined area. Consequently, surface erosion on exposed ground surfaces is a likely result during ongoing mining operations when heavy rains occur. Nevertheless, the quantity of material moved by rainstorms is expected to be small, or the trans-ported materials would be unlikely to enter streams, in most circumstances foreseen. For both alternatives, an undisturbed, no-work buffer between the mine activity area and Sucker Creek would act as a nearly continuous barrier to movement of materials detached from exposed aggregate and soil surfaces. However, two natural gaps occur in the buffer where Cedar Gulch and the un-named creek flow into Sucker Creek. It is at these locations, where the buffer is penetrated by existing water courses, that a pathway is present for erosion products to enter Sucker Creek. Moreover, fine-textured soils are most prevalent within and near these creeks. Therefore, the highest likelihood for erosion products to be mobilized and transported as sediment into Sucker Creek would occur when mining in or near the two small creeks (or during reconnection of these two tributaries) within the mine activity area. Mine excavations are expected to expose, pile and incise terrace substrate materials near these creeks. The arrangement and locations of piled and exposed materials would shift with the progress of mining and, indeed, the creek channels would be mined. Although dust would accom-pany mining activities, little effect is anticipated to adjacent areas or streams from wind-carried soil particles. Surface erosion would inevitably occur, however, during intense rain showers wherever steepened piles or cut slopes are exposed to sheet or gully runoff. Complete prevention of this transient surface erosion is difficult during on-going mining excavations but can be miti-gated somewhat by attentive placement of rock waste and stockpiles. Reclamation in Alternative 2 is anticipated to more rapidly remediate the conditions of exposed soil and barren surfaces in comparison to Alternative 1. Incorporation of sizeable quantities of organic matter in the upper placer profile and placing woody debris on the ground surface would likely enhance vegetative colonization of the site and thus would decrease potential for erosion short-term (Bennett 1982, Bowen et al. 2005). In addition, stabilization of stream banks with trees and shrubs has shown to offer erosion resistance from the fine root mass of the growing vegetation (Wynn et al. 2004). Planned plantings along the channel banks in Alternative 2 would ameliorate exposed soil conditions along stream banks and so would decrease erosion more rapidly than Alternative 1. Alternative 3 – No Action No erosion from anthropogenic activity would occur; however, natural erosion would still take place due to the forces of rain, wind and/or gravity. Site Productivity Effects As a rooting medium for higher plants, soil furnishes water, structural support, nutrients, aeration, cation exchange and soil biota that are essential for primary plant production. A close tie clearly exists between organic matter and the inherent mineral properties of a soil for sustaining a given site productivity (Jurgensen et al. 1996). Mixing, loss and/or displacement of topsoil and surface organic matter (OM) at a site affects soil physical and biological properties and so may reduce overall productivity and regeneration potential (Henderson 1995, Jurgensen et al. 1996). Alterations in soil structure can readily reduce soil moisture retention, lower cation exchange capacity or lessen nutrient availability.


Alternative 1 and Alternative 2: Mining excavations and use of heavy equipment would likely cause a decline in site productivity through mixing, sorting and displacement of terrace substrate materials. Mine excavations of existing placer aggregates and soils would decrease accumulated organic matter at the surface, where it is most useful, by mixing and resorting OM so that it is diminished by distribution throughout the rock spoils. Moreover, productivity on the mine site would be degraded because soil, organic materials and rock aggregates are likely to be mixed and resorted in such a way that coarse stones and subsoils dominate at or near the ground surface, even following reclamation. In addition, this placer deposit has been previously worked (more than once) during the last 150 years and, although partially recovered, is probably less productive than prior to the original mining entry. Observations of current conditions at the mine site suggest that site productivity may be lessened already because previous placer mining did undoubtedly cause surface soil removal, subsoil loss, degraded soil structure and a lack of surface litter or large organic debris (Borine 1983). Proposed mining would exacerbate this presumed earlier decline in soil OM and productivity. This is to say that a further (cumulative) decline in site productivity is likely and this decline is predicted to be a long-term impact, with recovery to current productivity perhaps taking a century or longer. While the site appears resilient to an irreversible decline in productivity, as evidenced by the regeneration and growth of trees since the last mining entry, the time needed for full recovery of site productivity to current (or pre-mining) conditions is not known. Still, plants are expected to grow on the site and improvement in site productivity would happen with time. Steady regeneration of site vegetation is expected following proposed placer mining even though this entry is likely to further deteriorate the soil mantle. Reclaimed mine spoils would at first have an exposed and barren ground surface and high rock content. These initial conditions probably would impede re-establishment of vegetation and would also slow plant growth, once establishment occurs. Because the disturbed area would be small (<8 acres) and narrow, however, adjacent forest conifers and hardwoods would immediately begin contributing organic matter in the form of fallen needles and leaves, broken limbs and root exudates2. These surrounding trees would therefore contribute a long-term and continuing supply of fine litter that is readily decom-posed and then incorporated into the surface profile by soil organisms (Ashby and Vogel 1994). Alternative 2, with its emphasis on returning considerable OM to the site, would accelerate soil development and vegetative recovery when compared to the basic re-contouring and shaping of Alternative 1. Because quantities of OM would be incorporated into the upper soil/rock profile and placed on top of the site in Alternative 2, water storage capacity and physical soil properties would be enhanced in comparison to a more limited replacement of OM (Amaranthus et al. 1989, Bowen et al. 2005). As well, above-ground woody residues can play an important role in site nutrition (nitrogen fixation) and animal activity (Harmon et al. 1994, Tallmon and Mills 1994). Thus, vegetation establishment is likely to be better supported. The more rapidly vegetation is established on site, the sooner exposed soil is covered and any lingering erosion is arrested (Brady and Weil 1999). As vegetative cover reduces the amount of exposed soil and erosion, site produc-tivity increases from the cumulative contribution of organic matter (Bowen et al. 2005). Since soil development and site productivity are dependent upon organic decomposition and mineral wea-thering (Brady and Weil 1999, McColl and Powers 2003, Jurgensen 2006), leaving greater amounts of woody residues jump-starts site recovery.

2 Low molecular weight metabolites that enter the soil from plant roots


Alternative 3 – No Action In the absence of mining, recovery of site productivity would continue into the future as organic matter accumulates and soil development takes place. Soil particles derived from weathering on site will be supplemented by decomposing organic matter and any addition of water-deposited soil and humic substances. This deposition will increase the site productivity with each incremental addition to the soil profile. REFERENCES Amaranthus, M.P., D.S. Parrish and D.A. Perry. 1989. Decaying logs as moisture reservoirs after drought and wildfire. Pages 191-194 In: Proc. Of Watershed ’89: a conference on the stewardship of soil, air, and water resources, E.B. Alexander (ed.). USDA Forest Service, Alaska Region. Juneau, AK. Ashby W.C. and W.G. Vogel. 1994. Tree planting on mined lands in the midwest: a handbook. Coal Research Center, Southern Illinois University. Carbondale, IL. Bendfeldt, E.S., J.A. Burger and W.L. Daniels. 2001. Quality of amended mine soils after sixteen years. Soil Sci. Soc. Am. J. 65:1736-1744. Bennett, K.A. 1982. Report to the Siuslaw National Forest. Effects of slash burning on surface soil erosion rates in the Oregon Coast Range. Borine, R. 1983. Soil survey of Josephine County, Oregon. USDA Soil Conservation Service. Scanned version of the original survey report available online at: http://soils.usda.gov/survey/online_surveys/oregon/#josephine1983. Bowen, C. K., G.E. Schuman, R.A. Olson and L.J. Ingram. 2005. Influence of topsoil depth on plant and soil attributes of 24-year old reclaimed mined lands. Arid Land Research and Management. Taylor & Francis, Inc. ISSN: 1532-4982 print/1532-4990 online. 19:267–284. Brady, N.C. and R.R. Weil. 1999. The nature and properties of soils, 12th ed. Prentice Hall, NJ. Coonce, L. 1991. FY 91 timber suitability update. Letter written regarding Umpqua National Forest direction for determining suitability, dated August 5, 1991. Roseburg, OR. Czapowskyj, M.M. 1978. Hybrid poplar on two anthracite coal-mine spoils: 10-yr results. USDA Forest Service, Northeast For. Exp. Sta. Res. Note NE-267. Broomall, PA. Fox, T.R. 2000. Sustained productivity in intensively managed forest plantations. Forest Ecology and Management. 138:187-202 Harmon, M.E., J. Sexton, B.A. Caldwell and S.E. Carpenter. 1994. Fungal sporocarp mediated losses of Ca, Fe, K, Mg, Mn, N, P, and Zn from conifer logs in the early stages of decomposition. Canadian Jouranl of Forest Research. 24:1883-1893. Henderson, G.S. 1995. Soil organic matter: a link between forest management and productivity. Pages 419-435 In: Carbon forms and functions in forest soils. McFee, W.W. and J.M. Kelly (eds.). Soil Science Society of America. Madison, WI. Jurgensen, M.F., A.E. Harvey, R.T. Graham, D.S. Page-Dumroese, J.R. Tonn, M.J. Larsen, and T.B. Jain. 1996. Impacts of timber harvesting on soil organic matter, nitrogen, productivity, and health of inland Northwest forests. Forest Science. 43(2):234-251.

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Jurgensen, M. 2006. Wood strength loss as a measure of decomposition in northern forest mineral soil. European Journal of Soil Biology. 42:23–31 Machulla, G., M.A. Bruns and K. M. Scow. 2005. Microbial properties of mine spoil materials in the initial stages of soil development. Soil Sci. Soc. Am. J. 69:1069–1077 McColl, J. G. and R. F. Powers. 2003. Decomposition of small woody debris of California red fir: mass loss and elemental content over 17 years. Soil Sci. Soc. Am. J. 67:1227–1233. McFee, W.W., W.R. Byrnes and J.G. Stockton. 1981. Characteristics of coal mine overburden important to plant growth. J. Environ. Qual. 10:300–308. Potter, K. N., F. S. Carter and E. C. Doll. 1998. Physical properties of constructed and undisturbed soils. Soil Sci Soc Am J. 52:1435-1438. Powers, R.F., D.A. Scott, F.G. Sanchez, R.A. Voldseth, D. Page-Dumroese, J.D. Elioff and D.M. Stone. 2005. The North American long-term soil productivity experiment: Findings from the first decade of research. Forest Ecology and Management. 220:31–50. Pritchett, W.L. and R.F. Fisher. 1987. Properties and management of forest soils. 2nd ed. p. 101, 179–218. John Wiley and Sons. New York, NY. Rodrigue, J.A. and Burger, J.A. 2004 Forest soil productivity of mined land in the midwestern and eastern coalfield regions. Soil Sci. Soc. Am. J. 68:833-844. Sandusky, J. 1980. Using trees on reclaimed mined lands in Southern Illinois. In: Proc., Symp. on Trees for Recla-mation in the Eastern U.S., Lexington, KY, 27–29 Oct. 1980. Interstate Mining Compact Commission, USDA Forest Service. Washington, DC. Sencindiver, J.C., and R.M. Smith. 1978. Soil and rock properties before and after mining. Pages 357–365 In: Forest soils and land use, C.T. Youngberg (ed.). Proc., 5th N. Am. Forest Soils Conf., Aug. 1978. Dep. Forest and Wood Sci., Colorado State University. Fort Collins, CO. Skovsgaard, J. P. and J. K. Vanclay. 2008. Forest site productivity: a review of the evolution of dendrometric concepts or even-aged stands. Forestry. 81(1):13-31. Tallmon, D. and L.S. Mills. 1994. Use of logs within home ranges of California red-backed voles on a remnant forest. J. of Mammology. 75(1):97-101. Thurman N.C. and J.C. Sencindiver. 1986. Properties, classification, and interpretations of minesoils at two sites in West Virginia. Soil Sci. Soc. Am. J. 50:181–185. USDA NRCS. 2000. Josephine series (1/2000 – last update). From: Official Soil Series Descriptions: View by Name Available online: http://www2.ftw.nrcs.usda.gov/osd/dat/J/JOSEPHINE.html. USDA Natural Resources Conserva-tion Service, Soil Survey Division. National Cooperative Soil Survey, USA. USDA NRCS. 2007. Web soil survey (6/20/2007 – last update). Available online: http://websoilsurvey.nrcs.usda.gov/app/. USDA Natural Resources Conservation Service. USDA Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. Handbook 18. Wade, G.L., J.T. Crews, and W.G. Vogel. 1985. Development and productivity of forest plantations on a surface mine in southeastern Kentucky. Pages 184–193 In: Proc., Better Reclamation with Trees Conf., Carbondale, IL, 5–7 June 1985. Southern Illinois Univ., Dep. of Botany. Carbondale, IL. Wynn, T.M., S. Mostaghimia, J.A. Burgerb, A.A. Harpolda, M.B. Hendersona and L. Henrya. 2004. Variation in root density along stream banks. J. Environ. Quality. 33:2030-2039.

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Attachment A – From: USDA NRCS 2000 JOSEPHINE SERIES Soils Description The Josephine series consists of deep, well drained soils that formed in colluvium and residuum weathered from altered sedimentary and extrusive igneous rocks. Josephine soils are on broad ridgetops, toeslopes, footslopes, and sideslopes of mountains. Slopes are 2 to 75 percent. The mean annual precipitation is about 45 inches and the mean annual temperature is about 50 degrees Fahrenheit. TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Haploxerults TYPICAL PEDON: Josephine gravelly loam, forested and on a 55 percent slope. (Colors are for moist soil unless otherwise stated.) Oi--2 inches to 0; partially decomposed litter of needles and leaves. A--0 to 3 inches; dark brown (7.5YR 3/2) gravelly loam, brown (10YR 5/3) dry; moderate fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine and common medium roots; many irregular pores; 25 percent gravel; moderately acid (pH 6.0); abrupt smooth boundary. (3 to 8 inches thick) BA--3 to 9 inches; brown (7.5YR 4/4) gravelly loam, light yellowish brown (10YR 6/4) dry; moderate fine and very fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many fine and very fine and common medium roots; many very fine tubular pores; 15 percent gravel; slightly acid (pH 6.2); clear smooth boundary. (5 to 20 inches thick) Bt1--9 to 16 inches; reddish brown (5YR 5/4) clay loam, pink (7.5YR 7/4) dry; moderate fine subangular blocky structure; hard, friable, sticky and plastic; common very fine, fine and medium roots; many very fine tubular pores; common distinct clay films; 10 percent partially weathered gravel; slightly acid (pH 6.1); clear smooth boundary. (5 to 10 inches thick) Bt2--16 to 32 inches; yellowish red (5YR 5/6) clay loam, pink (7.5YR 7/4) dry; moderate fine subangular blocky structure; very hard, friable, sticky and plastic; common very fine, fine and medium roots; many very fine tubular pores; common distinct clay films; 10 percent partially weathered gravel; strongly acid (pH 5.4); clear wavy boundary. (10 to 24 inches thick) Bt3--32 to 42 inches; yellowish red (5YR 4/6) clay loam, reddish yellow (5YR 6/6) dry; moderate medium and fine subangular blocky structure; very hard, friable, sticky and plastic; many very fine tubular pores; common distinct clay films; 12 percent partially weathered gravel; very strongly acid (pH 5.0); clear wavy boundary. (5 to 12 inches thick) BC--42 to 51 inches; yellowish red (5YR 4/6) gravelly clay loam, reddish yellow (5YR 6/6) dry; weak medium and fine subangular blocky structure; hard, friable, sticky and plastic; many very fine tubular pores; 20 percent partially weathered gravel; very strongly acid (pH 4.9); clear wavy boundary. (0 to 10 inches thick)


BCt--51 to 59 inches; yellowish red (5YR 5/6) gravelly clay loam, reddish yellow (7.5YR 6/6) dry; massive; dark red (2.5YR 3/6) clay films in joints; common black stains; 20 percent angular saprolitic gravel and 30 percent hard angular gravel; very strongly acid (pH 4.9); gradual wavy boundary. (0 to 15 inches thick) Crt--59 inches; saprolitic siltstone; red clay films and black stains in fractures; very strongly acid (pH 4.9). TYPE LOCATION: Josephine County, Oregon; about 7 miles south of Selma near the east fork of McMullin Creek; about 520 feet north and 130 feet east of the SW corner of sec. 33, T. 38 S., R. 7 W. RANGE IN CHARACTERISTICS: The soils are dry during the summer for 60 to 90 consecutive days in Oregon and 90 to 110 in California in all parts of the moisture control section. The soils also are moist during the winter. The mean annual soil temperature is 47 to 56 degrees F. Depth to bedrock ranges from 40 to 60 inches. Uncoated sand and silt coatings are common on faces of peds in the upper part of the B horizon in some pedons. The A horizon has hue of 5YR through 10YR, value of 2 through 4 moist and 5 or 6 dry and chroma of 2 through 4 moist and dry. It has 10 to 30 percent soft rock fragments and 15 to 30 percent gravel. It is strongly acid to slightly acid. The BA horizon has hue of 10YR through 5YR, value of 3 or 4 moist, 5 to 7 dry, and chroma of 4 through 6 moist and dry. It has 15 to 30 percent soft rock fragments and 15 to 30 percent gravel. The Bt horizon has hue of 5YR or 2.5YR moist and 7.5YR or 5YR dry, value of 3 through 5 moist, 4 through 8 dry, and chroma of 4 through 6 moist and dry. It averages 27 to 35 percent clay and 0 to 35 percent partially weathered and unweathered gravel. It has weak or moderate structure and few to common, faint to distinct clay films. It is slightly acid to very strongly acid with acidity decreasing with depth. The BC horizon has similar ranges in color and texture but gravel content is 15 to 50 percent. It is gravelly clay loam, gravelly silty clay loam, very gravelly clay loam or very gravelly silty clay loam. COMPETING SERIES: These are the Acker, Diamond Springs and Jocal series. Acker soils have a Bt horizon with moist hue yellower than 7.5YR and are dry for 45 to 60 consecutive days. Diamond Springs soils are 24 to 40 inches deep to a paralithic contact, have a Bt horizon domi-nantly yellower than 7.5YR hue and are structureless. Jocal soils are dry for 90 consecutive days or more during the summer. GEOGRAPHIC SETTING: Josephine soils are on broad ridgetops, toeslopes, footslopes, and side slopes of mountains. Elevations are 200 to 4,000 feet in Oregon and up to 5,500 in California. Slope gradients dominantly are 35 to 60 percent but range from 2 to 75 percent. The soils formed in moderately fine textured colluvium and residuum weathered from sedimentary, metamorphosed sedimentary, and volcanic rocks. The climate consists of hot, dry summers and warm, moist to wet winters.


The mean annual precipitation is typically 30 to 60 inches but may range up to 70 inches in California and up to 100 inches in the interior mountains of Curry County, Oregon. The mean annual temperature is 45 to 54 degrees F in Oregon and as high as 58 degrees F in California. The average January temperature is about 35 degrees F, and the average July temperature is about 65 degrees F. The frost-free period is about 100 to 235 days in Oregon and as many as 260 days in California. GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beekman, Colestine, Pollard, Speaker and Vermisa soils. Beekman, Colestine and Vermisa soils lack an argillic horizon and are less than 40 inches deep to bedrock. Pollard soils occupy gently sloping to moderately steep terraces and are clayey in the control section. Speaker soils are 20 to 40 inches deep to bedrock. DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability. USE AND VEGETATION: Woodland, wildlife habitat and water supply. Native vegetation is Douglas fir, ponderosa pine, Pacific madrone, California black oak, tanoak, incense cedar, sugar pine, cascade Oregon grape and common snowberry in Oregon, and in California the dominant tree is ponderosa pine. DISTRIBUTION AND EXTENT: Klamath Mountains of southern Oregon (MLRA 5) and in the Sierra Nevada in northern California (MLRA 22). The series is extensive. MLRA OFFICE RESPONSIBLE: Davis, California SERIES ESTABLISHED: Josephine County, Oregon, 1919. REMARKS: The areas identified as Josephine in the Sierra Nevada Range (MLRA 22) in Califor-nia have been correlated to the Jocal series. Upon revision of the MUUF file for California, references to California in this series description will be removed. CEC activity class superactive added 1/2000, competing series not updated at that time. Diagnostic horizons and features recog-nized in this pedon: Argillic horizon - from 9 to 42 inches (Bt1, Bt2, and Bt3 horizons) Particle-size control section - from 9 to 29 inches (Bt1 horizon and part of Bt2 horizon) ADDITIONAL DATA: Characterization data on two profiles (S69-Oreg-17-1 and 17-2) reported in Riverside Laboratory print-outs for soils sampled in Jackson and Josephine Counties, Oregon in 1969. Profile S69-Oreg-17-1 is the typical pedon.


Attachment B Rock fragments within the soil profile and on the ground surface are categorized into size ranges, using the cross-sectional dimension of the rock, and identified by a specific term that denotes the size range. The following 3 tables show the classifications used in this report.

Table 1. Textural classes and size of each class.

Fine Earth (or Soil) Particle Size Classes Size in millimeters (mm) Clay <0.002 Silt 0.002 to .05 Sand 0.05 to 2

Table 2. Terms for Rock Fragments. Information adapted from USDA Soil Survey Manual, Chapter 3. Shape and size1 Spherical, cubelike, or equiaxial:

Noun Adjective

1/16 to 3 inches diameter Pebbles Gravelly 1/16 to 3/16 inch diameter Fine Fine gravelly 3/16 to 3/4 inch diameter Medium Medium gravelly 3/4 to 3 inch diameter Coarse Coarse gravelly 3 to 10 inch diameter Cobbles Cobbly. 10 to 24 inch diameter Stones Stony. >24 inch diameter Boulders Bouldery. Flat: 1/16 to 6 inch long Channers Channery. 6 to 15 inch long Flagstones Flaggy. 15 to 24 inch long Stones Stony. >24 inch long Boulders Bouldery. 1 The roundness of the fragments may be indicated as angular (strongly developed faces with sharp edges), irregular (prominent flat faces with incipient rounding or corners), subrounded (detectable flat faces with well-rounded corners), and rounded (flat faces absent or nearly absent with all corners.

Table 3. Rock fragments at the surface. Information adapted from USDA Soil Survey Manual Chapter 3. Stone Class % Stones on

surface Size and Distance between of Stones

Class 1 <1 Stones of the smallest sizes are at least 26 ft apart; boulders of the smallest sizes are at least 65 ft apart

Class 2 <1-3 Stones of the smallest sizes are not less than 3 ft apart; boulders of the smallest size are no less than 9 ft apart.

Class 3 3-15 Stones of the smallest size are as little as 1 ft apart; boulders of the smallest size are as little as 3 ft apart

Class 4 15-50 Stones of the smallest size are as little as 11 in apart; boulders of the smallest size are as little as 20 in apart.

Class 5 50-90 Stones of the smallest size are less than 2 in apart; boulders of the smallest size are less than 2 in apart.

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