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HomeMy WebLinkAboutFile Documents.800 S Monarch St.0062-2021-BRES (19) DRAINAGE REPORT FOR 800 S MONARCH ST. ASPEN, CO 81611 I hereby affirm that this report and the accompanying drawings for the analysis of 800 S Monarch Street, Aspen, Colorado was prepared under my direct supervision for the owners thereof in accordance with the provisions of the City of Aspen Urban Runoff Management Plan with proposed variances and exceptions listed thereto. I understand that it is the policy of the City of Aspen that the City of Aspen does not and will not assume liability for drainage facilities designed by others. Permit #: 0016-2020-BRES May 24, 2022 Rick Barth, P.E. 36749 Prepared by 118 West Sixth Street, Suite 200 Glenwood Springs, CO 81601 970.945.1004 970.945.5948 fax 05/25/2022 Reviewed by Engineering 06/07/2022 9:51:27 AM "It should be known that this review shall not relieve the applicant of their responsibility to comply with the requirements of the City of Aspen. The review and approval by the City is offered only to assist the applicant's understanding of the applicable Engineering requirements." The issuance of a permit based on construction documents and other data shall not prevent the City of Aspen from requiring the correction of errors in the construction documents and other data. 800 S Monarch Street, Aspen, Colorado May 24, 2022 Drainage Report for Major Design i DRAINAGE REPORT FOR 800 S MONARCH ST. ASPEN, CO 81611 REVIEWED BY RICK BARTH SGM Project # 2020-452.001 05/25/2022 800 S Monarch Street, Aspen, Colorado May 24, 2022 Drainage Report for Major Design ii TABLE OF CONTENTS 1.0 Existing Site 3 1.1 Description of Existing Site 3 1.2 Description of Existing Drainage 3 2.0 Proposed Project 3 3.0 Proposed Basins 3 3.1 Basin 1 4 3.2 Off-site 4 4.0 Water Quality Methodology 4 5.0 Maintenance 5 5.1 Drywell 5 6.0 Conclusion 5 LIST OF APPENDICES Appendix A – Proposed Drainage Schematic Appendix B – Water Quality Capture Volume Calculations Appendix C – Slot Drain Capacity Appendix D – Drywell Drain Down Calculations Appendix E – Outflow Pipe Capacity Appendix F – Side Channel Capacity Appendix G – Web Soil Survey 05/25/2022 800 S Monarch Street, Aspen, Colorado May 24, 2022 Drainage Report for Major Design 3 1.0 Existing Site 1.1 Description of Existing Site The physical address of the project is 800 S Monarch Street, Aspen, Colorado, and it is located on parcel no. 2735-131-28-800. This parcel is approximately 43,500 square feet and is owned by various owners as part of the Mountain Queen Condo Association. The existing structures on the parcel is a condo complex that will remain unchanged in terms of the residences. The project focuses on demolishing the pool deck and rebuilding a new one. 1.2 Description of Existing Drainage Existing storm water is collected on the pool deck through area drains and is known to drain to the sanitary service system, an approach that will not be allowed for the new pool deck. Topography of the site suggests that the existing drainage patterns flow from the south side of the property to the north side of the property. There are no apparent erosive or runoff issues (gullies, channels, etc.). A web soil survey was performed and found the soils to be Mine loam, classified as Hydrologic Soil Group A will well-draining soils consisting of gravelly and cobbly sandy loam to very gravelly and cobbly sandy loam. There is no existing offsite runoff that enters the property. The property will not require detention beyond the water quality capture volume (WQCV) as it exists within the Aspen Mountain Drainage Basin. 2.0 Proposed Project The primary purpose of this project is to replace and pool deck and build a new spa and pool deck. Other improvements include the addition of onsite snowmelt and improving storm water runoff quality. The proposed project is considered a major project as defined by the COA Urban Runoff Management Plan (URMP) because more than 1000 square feet but less than 25% of the site will be disturbed. For this disturbance, only the new impervious area will be required to be treated for water quality. The proposed pool deck will have a footprint of roughly 2400 square feet and consist of a spa and pool deck. Storm water quality improvements consist of slot drains directed to one (1) water quality drywell. The drywell is sized to treat the impervious area that is being changed on site. In addition, an outflow pipe will be utilized to direct stormwater on the side of the property with gravel at the outlet to prevent erosion. This runoff will travel down an improved drainage swale that will end up at the ROW at the north end of the property. 3.0 Proposed Basins The proposed site has 1 basin, as shown in Appendix A. Detailed calculations for the basin can be found in Appendix C. Storm water runoff will be routed to the designated BMP for 05/25/2022 800 S Monarch Street, Aspen, Colorado May 24, 2022 Drainage Report for Major Design 4 water quality treatment through a combination of grading, inlets, and drainpipe. All proposed storm water runoff will discharge from the site in a northernly direction to match historical flow patterns. The basin is detailed in the section that follows, with a description on how the required WQCV is treated by the BMP within the basin. WQCV is calculated based on the proposed water quality drywell. Table 1 – Pipe Capacity 3.1 Basin 1 Basin 1 is located on the SW corner of the property. This basin is 2142 square feet of which 2142 square feet is impervious. One drywell will be used to treat the WQCV. See Appendix A for the proposed location of the BMP in this basin. A portion of this area is snow melted impervious area with slot inlets that will collect water and direct it to the water quality drywell that is 4’ in diameter and 5’ deep. Calculations for the drain down time of the drywell can be seen in the Appendix. Perforations and gravel void space are proposed away from the pool to prevent risk to the existing pool. Storm water will be routed from the pool deck to the drywell in the upper section of the drywell to collect sediment and silt and prevent clogging and ease with future maintenance. The drywell will have an outlet line that runs north along the side of the property and discharges on the east side of the property with a rock outfall to prevent erosion. The stormwater will infiltrate into the native hillside and run north in a historical manner until it reaches the ROW. Drainage will utilize a roadside swale and, if needed, will be improved to provide adequate drainage capacity and capability. A 4” schedule 40 PVC will be utilized as the outlet pipe with an end cap and a drilled 0.5” hole that will restrict outlet flows to less than historic rates. Tree canopy credit within the tributary area of the proposed development is counted as a reduction in water quality treatment. 1629 square feet of deciduous and 202 square feet of coniferous tree canopy was utilized for a total of 305 square feet of tree canopy credit. 3.2 Off-site Off-site drainage will be untouched, specifically the drainage swale that is not on this property and located to the east that is utilized for mudflow as well. The potential area of blockage of the structure will remain unchanged in terms of mudflow. Grading for this project’s drainage swale will be a 3” deep swale that is only on the property and does not affect or damage the drainage swale to the east. 4.0 Water Quality Methodology The Required WQCV (cf) for the basin on the property was estimated from Figure 8.13 of the URMP based on the basin imperviousness and basin area. These calculations can be seen in the Appendix and take no credits for grass buffer or other BMPs. 05/25/2022 800 S Monarch Street, Aspen, Colorado May 24, 2022 Drainage Report for Major Design 5 5.0 Maintenance 5.1 Drywell Dry wells must be inspected and maintained yearly to remove sediment and debris that is washed into them. Minimum inspection and maintenance requirements include the following: • Inspect dry wells as annually and after every storm exceeding 0.5 inches. • Dispose of sediment, debris/trash, and any other waste material removed from a dry well at suitable disposal sites and in compliance with local, state, and federal waste regulations. • Routinely evaluate the drain-down time of the dry well to ensure the maximum time of 24 hours are not being exceeded. If drain-down times are exceeding the maximum, drain the drywell via pumping and clean out the percolation area (the percolation barrel may be jetted to remove sediment accumulated in perforations). Consider drilling additional perforations in the barrel. Check outlet cap with drilled hole to ensure clogging has not affected the drainage pipe. If slow drainage persists, the system may need to be replaced. 6.0 Conclusion The proposed BMP (water quality drywell) is expected to treat 100% of the required WQCV at the 800 S Monarch Street project with room to spare. With proper maintenance and installation, this BMP will meet the criteria outlined in the City of Aspen’s current Urban Runoff Management Plan. 05/25/2022 05/25/2022 Input Calculation Sub Basin Basin Name Total Area Imp. Area Imperv- iousness Req'd WQCV (depth) Req'd WQCV (vol.) Decid. Area Conif. Area Drywell Volume Canopy Credit Eff. Imp. Area Eff. Imperv- iousness Eff. WQCV (depth) Net WQCV (#)(sq. ft.)(sq. ft.)(%)(in)(cu. ft.)(sq. ft.)(sq. ft.)(cu. ft.)(sq. ft.)(sq. ft.)(%)(in)(cu. ft.) 1 2142 2142 100%0.256 45.6 1629.0 202.0 63.0 305.0 1837 86%0.19 -28.8 Total 2142 2142 100%0.256 45.6 1629.0 202.0 63.0 305.0 1837 86%0.19 -28.8 Legend 05/25/2022 2/10/22, 1:21 PM HYDROlite | ACO https://hydrolite.acotechsupport.com 1/2 HYDROlite   STEP 4: REGISTER & VIEW RESULTS MTN QUEEN Summar y of input data and calculations. Drainage Area 3726 ft² Length of Drain to Outlet 127.95 ft (39m) Internal Channel Width 100mm (4") Rainfall Intensity 1.23 inch/hr Longitudinal Slope 0.5% Design Discharge 47.63 GPM Lateral Intake 0.372 GPM/ft 05/25/2022 2/10/22, 1:21 PM HYDROlite | ACO https://hydrolite.acotechsupport.com 2/2 RESULT S 4" Sloped (shallow) Sloped (0.5% built-in fall) Channel Numbers: 1 to 20 (20 units) Constant Depth (Neutral) Channel Numbers: 010 / 020 (9 / 10 units) Invert Depth: 100mm (3.94") to 200mm (7.87") Typical run (PDF) 25% Utilization Capacity is defined as 100% 4" Sloped (standard) Sloped (0.5% built-in fall) Channel Numbers: 1 to 39 (39 units) Invert Depth: 100mm (3.94") to 295mm (11.61") Typical run (PDF) 17% Utilization Capacity is defined as 100% 4" Sloped (deep) Sloped (0.5% built-in fall) Channel Numbers: 2 to 40 (39 units) Invert Depth: 105mm (4.13") to 300mm (11.81") Typical run (PDF) 17% Utilization Capacity is defined as 100% A note on specification Based on your inputs, this is a hydraulic recommendation to guide you on the optimal channel size and configuration. Select (tick) your preferred option above and hit the Inquire button below to request a full trench drain recommendation taking also into account loading, site and user requirements. For more info on this calculation, click here. 05/25/2022 K K Vr AP Drywell AP (2' dia. x 2.5' H) Available AP (71%) percolated 3 6.94444E-05 145.73 48.58 37.70 26.81 in/hr ft/sec cuft sqft sqft sqft Ouflow Drain Time Drain Time 0.023 6336.14 1.76 cfs seconds hours AP (Vr) / (K) (43,200)Percolation Area (Page 8-117 URMP): 05/25/2022 C₀g H₀A₀I.D.Q -ft/sec²ft ft²in.cfs 0.6 32.2 0.75 0.005 4.0 0.023 Orifice Area PVC Diameter Actual Outflow Q Historic 100 year Flow Rate (Q) Discharge Coefficient Gravitational Constant Headwater Depth cfs 0.029 05/25/2022 Channel Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Tuesday, May 3 2022 <Name> Triangular Side Slopes (z:1) = 10.00, 10.00 Total Depth (ft) = 0.25 Invert Elev (ft) = 8031.00 Slope (%) = 17.50 N-Value = 0.030 Calculations Compute by: Known Depth Known Depth (ft) = 0.20 Highlighted Depth (ft) = 0.20 Q (cfs) = 1.778 Area (sqft) = 0.40 Velocity (ft/s) = 4.45 Wetted Perim (ft) = 4.02 Crit Depth, Yc (ft) = 0.25 Top Width (ft) = 4.00 EGL (ft) = 0.51 0 1 2 3 4 5 6 7 Elev (ft)Depth (ft)Section 8030.75 -0.25 8031.00 0.00 8031.25 0.25 8031.50 0.50 8031.75 0.75 8032.00 1.00 Reach (ft) Swale flow at 80% capacity (full) 05/25/2022 Channel Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Tuesday, May 3 2022 <Name> Triangular Side Slopes (z:1) = 10.00, 10.00 Total Depth (ft) = 0.25 Invert Elev (ft) = 8031.00 Slope (%) = 17.50 N-Value = 0.030 Calculations Compute by: Known Q Known Q (cfs) = 0.03 Highlighted Depth (ft) = 0.05 Q (cfs) = 0.030 Area (sqft) = 0.03 Velocity (ft/s) = 1.20 Wetted Perim (ft) = 1.00 Crit Depth, Yc (ft) = 0.06 Top Width (ft) = 1.00 EGL (ft) = 0.07 0 1 2 3 4 5 6 7 Elev (ft)Depth (ft)Section 8030.75 -0.25 8031.00 0.00 8031.25 0.25 8031.50 0.50 8031.75 0.75 8032.00 1.00 Reach (ft) Swale flow at historic flow limit 05/25/2022 United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Aspen-Gypsum Area, Colorado, Parts of Eagle, Garfield, and Pitkin Counties Natural Resources Conservation Service October 19, 2020 05/25/2022 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 05/25/2022 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 05/25/2022 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................11 Map Unit Descriptions.........................................................................................11 Aspen-Gypsum Area, Colorado, Parts of Eagle, Garfield, and Pitkin Counties...................................................................................................13 77—Mine loam, 25 to 65 percent slopes.....................................................13 108—Uracca, moist-Mergel complex, 6 to 12 percent slopes, extremely...14 References............................................................................................................16 4 05/25/2022 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 05/25/2022 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 05/25/2022 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 05/25/2022 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 05/25/2022 9 Custom Soil Resource Report Soil Map 43 3 8 8 7 9 43 3 8 8 8 5 43 3 8 8 9 1 43 3 8 8 9 7 43 3 8 9 0 3 43 3 8 9 0 9 43 3 8 9 1 5 43 3 8 8 7 9 43 3 8 8 8 5 43 3 8 8 9 1 43 3 8 8 9 7 43 3 8 9 0 3 43 3 8 9 0 9 342601 342607 342613 342619 342625 342631 342637 342643 342649 342655 342601 342607 342613 342619 342625 342631 342637 342643 342649 342655 39° 11' 6'' N 10 6 ° 4 9 ' 2 0 ' ' W 39° 11' 6'' N 10 6 ° 4 9 ' 1 8 ' ' W 39° 11' 5'' N 10 6 ° 4 9 ' 2 0 ' ' W 39° 11' 5'' N 10 6 ° 4 9 ' 1 8 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 10 20 40 60 Feet 0 3 7 14 21 Meters Map Scale: 1:256 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. potential drywell location 05/25/2022 MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Aspen-Gypsum Area, Colorado, Parts of Eagle, Garfield, and Pitkin Counties Survey Area Data: Version 11, Jun 5, 2020 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Data not available. The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 05/25/2022 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 77 Mine loam, 25 to 65 percent slopes 0.1 86.3% 108 Uracca, moist-Mergel complex, 6 to 12 percent slopes, extremely 0.0 13.7% Totals for Area of Interest 0.1 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the Custom Soil Resource Report 11 05/25/2022 development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 05/25/2022 Aspen-Gypsum Area, Colorado, Parts of Eagle, Garfield, and Pitkin Counties 77—Mine loam, 25 to 65 percent slopes Map Unit Setting National map unit symbol: jq76 Elevation: 7,500 to 9,500 feet Mean annual precipitation: 18 to 20 inches Mean annual air temperature: 36 to 40 degrees F Frost-free period: 70 to 80 days Farmland classification: Not prime farmland Map Unit Composition Mine and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Mine Setting Landform:Fans, valley sides Down-slope shape:Concave Across-slope shape:Concave Parent material:Moderately coarse alluvium derived from metamorphic rock and/or moderately coarse colluvium derived from metamorphic rock Typical profile H1 - 0 to 4 inches: loam H2 - 4 to 16 inches: gravelly sandy loam H3 - 16 to 32 inches: cobbly sandy loam H4 - 32 to 37 inches: gravelly sandy loam H5 - 37 to 45 inches: very cobbly loamy sand H6 - 45 to 60 inches: very gravelly sandy loam Properties and qualities Slope:25 to 65 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.60 to 6.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Available water capacity:Low (about 4.8 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: A Other vegetative classification: Spruce-Fir (null_21) Hydric soil rating: No Custom Soil Resource Report 13 05/25/2022 Minor Components Other soils Percent of map unit:15 percent Hydric soil rating: No 108—Uracca, moist-Mergel complex, 6 to 12 percent slopes, extremely Map Unit Setting National map unit symbol: jq4h Elevation: 6,800 to 8,400 feet Mean annual precipitation: 16 to 19 inches Mean annual air temperature: 40 to 43 degrees F Frost-free period: 75 to 95 days Farmland classification: Not prime farmland Map Unit Composition Uracca, moist, and similar soils:50 percent Mergel and similar soils:40 percent Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Uracca, Moist Setting Landform:Alluvial fans, structural benches, valley sides Down-slope shape:Linear Across-slope shape:Linear Parent material:Mixed alluvium derived from igneous and metamorphic rock Typical profile H1 - 0 to 8 inches: cobbly sandy loam H2 - 8 to 15 inches: very cobbly sandy clay loam H3 - 15 to 60 inches: extremely cobbly loamy sand Properties and qualities Slope:6 to 12 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.20 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:10 percent Available water capacity:Very low (about 2.6 inches) Interpretive groups Land capability classification (irrigated): None specified Custom Soil Resource Report 14 05/25/2022 Land capability classification (nonirrigated): 6e Hydrologic Soil Group: B Ecological site: R048AY237CO - Stony Loam Other vegetative classification: Stony Loam (null_82) Hydric soil rating: No Description of Mergel Setting Landform:Structural benches, valley sides, alluvial fans Down-slope shape:Linear Across-slope shape:Linear Parent material:Glacial outwash Typical profile H1 - 0 to 8 inches: cobbly loam H2 - 8 to 20 inches: very cobbly sandy loam H3 - 20 to 60 inches: extremely stony sandy loam Properties and qualities Slope:6 to 12 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.60 to 6.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:10 percent Available water capacity:Low (about 3.3 inches) Interpretive groups Land capability classification (irrigated): 4s Land capability classification (nonirrigated): 4s Hydrologic Soil Group: A Ecological site: R048AY237CO - Stony Loam Other vegetative classification: Stony Loam (null_82) Hydric soil rating: No Minor Components Other soils Percent of map unit:10 percent Hydric soil rating: No Custom Soil Resource Report 15 05/25/2022 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 16 05/25/2022 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 17 05/25/2022