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HomeMy WebLinkAboutALLIED BUILDING PRODUCTS - PDP - PDP180015 - SUBMITTAL DOCUMENTS - ROUND 2 - EROSION CONTROL LETTER/REPORTPDP EROSION CONTROL REPORT ALLIED BUILDING PRODUCTS LOCATED AT 2155 MIDPOINT DRIVE CITY OF FORT COLLINS, STATE OF COLORADO Prepared By: Baseline Engineering Corporation 4007 S. Lincoln Ave, Suite 405 Loveland, CO 80537 Todd Rand, PE _____________________________ October 3, 2018 Rev. November 19, 2018 2 Table of Contents I. General Location and Descriptions .................................................................................................. 3 A. Erosion Analysis ........................................................................................................................... 3 B. Storm Water Management Controls ........................................................................................... 4 C. Establishment of Dryland Vegetation .......................................................................................... 6 D. Detailed Sequence of Construction Activities ............................................................................. 7 E. Erosion Control Security Calculations .......................................................................................... 7 II. References ....................................................................................................................................... 7 VI. APPENDIX ................................................................................................................................................. 8 A. Sequence of Construction Activity .......................................................................................................... 9 B. Erosion and Sediment Control Escrow/Security Calculation for .......................................................... 10 The City of Fort Collins ............................................................................................................................... 10 C. NRCS Soil Resource Report .................................................................................................................... 11 D. Guidelines for Revegetation of Disturbed Areas .................................................................................. 12 3 I. General Location and Descriptions A. Erosion Analysis The project site is currently an undeveloped platted lot of 1.853 acres. The site slopes towards the east. The majority of the site has a slight 1 to 2 percent slope to the east; the southern edge has a slope of 3 to 5 percent slope to the east. The site is approximately 50% vegetated with native grasses and weeds. The site is mowed at least annually and non-irrigated. The lot contains existing easements on the east, south and west sides dedicated to access, drainage and utilities. A City of Fort Collins sanitary and water mains are contained in the western easement along with access to Lots 1 and 3 of Centerpoint Plaza. A building material storage building is proposed for the site. Construction of the project is expected to disturb approximately 1.51 acres. Construction will consist of stripping and stocking topsoil, site grading, hardscape, paving, building construction and landscaping. Site drainage will be conveyed to Spring Creek in an existing City of Fort Collins storm sewer, installed in the southern portion of Lot 1. Currently, site drainage sheet flows to the eastern lot line of Lot 2, then flows south through Lot 3. The existing flows eventually reach the Cache La Poudre River approximately three-quarter miles to the east of the site in old irrigation laterals on the north side of the railroad tracts. The Cache La Poudre River then flows into the South Platte River approximately 5 miles east of the City of Greeley Colorado. Proposed site grading will direct the flows from impervious surfaces west to the existing WQ pond in the southern portion of Lot 1. Flows from the WQ pond are directed west approximately 230 ft and then north 570 ft where it outfalls into Spring Creek. Spring Creek ultimately discharges into the Poudre River approximately 0.57 miles to the east. An NRCS Soil Resource Report classifies the soil in the disturbed area as Loveland clay loam, 1 to 3 percent slopes and 0 to 1 percent slopes. The report addresses the following Soil Erosion Factors:  K Factor, Rock Free. Erosion factor K indicates the susceptibility of a soil to sheet and rill erosion by water. Values of K range from 0.02 to 0.69. Other factors being equal, the higher the value, the more susceptible the soil is to sheet and rill erosion by water. The Table-K Factor, Rock Free rates the site 0.20.  T Factor. Erosion factor T is an estimate of the maximum average annual rate of soil erosion by wind and/or water that can occur without affecting crop productivity over a sustained period. The rate is in tons per acre per year. The Table-T Factor rates the site 3.  Wind Erodibility Index. The wind erodibility index is a numerical value indicating the susceptibility of soil to wind erosion, or the tons per acre per year that can be expected to be lost to wind erosion. The Table-Wind Erodibility Index, gives the site a rating of 48. The loss rating goes from 0 (zero) to 310 tons per acre per year. 4 The site is susceptible to and, shall be protected against water and wind erosion potential during construction until paving operations, landscape installation and permanent erosion controls are completed. A copy of the NRCS report is included in this report. B. Storm Water Management Controls Prior to mobilization of equipment on site, installation of flow barriers shall be completed on the edge of all disturbed areas. Existing inlets shall have sediment filters installed prior to land disturbance activities, to control conveyance of sediments into existing streets and storm sewer systems. Site grading shall include installation of a vehicle tracking pad, a temporary sediment basin, and a concrete washout basin. Sediment protection shall be installed in the swale to the existing Water Quality pond, sediment protection shall be installed before land disturbance and removed after landscape and hardscape installation. The vehicle sediment tracking pad shall be removed prior to paving installation. Inlet protection shall be removed when installation of flat work and paving has been completed and the potential for conveyance of construction sediment from the site to the public ROW has been eliminated. Flow barriers shall be removed after all landscaping is completed and reseeding is established. Refer to the Sequence of Construction Activity in this report for additional sequence detail. i. The site SWMP Administration will be the General Contractor selected for the project build out. Dohn Construction, Inc’s, Project Manager’s contact information is provided below until the General Contractor is selected. Garth McCann, Preconstruction Manager Cell number: Fax number: 970-490-1855 Address: 2642 Midpoint Dr., Fort Collins, CO 80525 Email: ii. Sources of Potential Pollutants: Sources are sediment contained in storm water runoff. Sediment will be controlled by a BMP selection of Fiber Flow Barriers, Inlet Socks, Vehicle Tracking Control pad, Concrete Washout and site watering. 1. Disturbed and stored soils: The project site disturbance area will be limited to approximately 1.51 acres. Typically these sites do not have soil stockpiles, if 5 there are; the topsoil will be stripped in the disturbance area and stockpiled at the south end of the lot. BMP measures to control water and wind conveyance of stored soil’s, sediment shall consist of the following: The stockpile shall have a flow barrier installed around the perimeter of the toe of slope to control water based conveyance of sediment and shall also be included in site watering to prevent and control wind generated conveyance of fugitive dust. 2. Vehicle tracking of sediments: The site will have a single, dedicated access entrance with a VTC pad. Any tracked sediment on paved City streets will be removed by sweeping and scraping at the end of day as necessary. The nearest existing inlets on Midpoint Drive, are approximately 1,900 ft. southeast of the site. Sediment protection in the south curb and gutter of Midpoint Drive, from the construction entrance east to Specht Point Road, will be installed prior to construction activities and will be inspected on a scheduled basis and after each storm event. 3. Management of contaminated soils: There are no known contaminated soils on the site. If contaminated soils are located, the project Geotech will be notified to inspect the contaminated area and advise of disposal procedures. 4. Loading and unloading operations: Due to the size of the project, equipment and materials will be unloaded on the site as much as possible for the project duration. Any movement of soil from the site will be removed as described in ii.2. 5. Outdoor storage activities: Due to the project size, building materials shall be scheduled for delivery as needed to minimize material storage. Landscape materials shall be scheduled for delivery as needed during installation. Storage of fertilizers, chemicals or other hazardous materials during project construction is not anticipated based on previous projects. Any movement of soil from the site will be removed as described in ii.2. BMP’s for shipping materials such as pallets, straps, boxes, plastic wrapping etc. shall be disposed of in non-industrial waste receptacles located near the site entrance at the time of use. 6. Vehicle and equipment maintenance and fueling: Site dirt work will be minor and short term. Most of the project equipment are in good working order when onsite. Maintenance and fueling as necessary will be conducted on-site in a designated staging area. The staging area shall have a low dirt berm installed around the perimeter to prevent migration of fluids prior to clean up should a spill occur. Contaminated soils shall be disposed of properly. 7. Significant dust or particulate generating processes: The site shall be watered regularly during grading operations. Once grading is complete, Curb and Gutter, and paving of the parking lot will be completed, further reducing dust or particulate occurrences. Landscape areas and areas of disturbance outside of landscape limits will continue to be watered until landscaping and reseeding is completed. A wind barrier fence shall be installed if site watering is ineffective and construction activity cannot be halted. Any disturbed or exposed soil 6 surface areas that will be inactive for more than 30 days or while vegetation is being established shall be seeded and or watered to prevent soil loses. A copy of the Dust Prevention and Control Manual shall be referenced for additional BMP’s should additional dust prevention and control be necessary in addition to these methods. 8. Routine maintenance activities involving fertilizers, pesticides, detergents, fuels, solvents, oils, etc.: It is not anticipated any of these materials will be used for routine maintenance activities. If necessary these activities will take place in the designated staging area. Any losses will be swept or otherwise collected and properly disposed of daily. The staging area shall have a low dirt berm installed around the perimeter to prevent migration of fluids prior to clean up should a spill occur. Contaminated soils shall be disposed of properly. 9. On-site waste management practices: On-site waste will be collected in approved rented receptacles located near the construction entrance for ease of removal. 10. Concrete truck/equipment washing, including the concrete truck chute and associated fixtures and equipment: A concrete washout area will be provided and signed near the construction entrance. The Contractor shall be responsible for any loses outside of the concrete washout area and contacting the supplier of the violation. 11. Dedicated asphalt and concrete batch plants: THERE WILL BE NO BATCH PLANTS ON SITE. 12. Non-industrial waste sources: These will be provided near the construction entrance and separated from the construction waste collection containers. 13. Other areas or procedures where potential spills can occur: Saw cutting activities shall prevent the public from entering the area where dust emissions occur. Saw cutting shall be temporarily halted during high wind events greater than 30 mph if operations would result in off-property transport. Equipment and work area clean up shall use wet wiping, wet sweeping, or vacuuming with HEPA filtration for equipment and work area clean up to prevent dust to become airborne during clean up. Slurry clean up shall prevent water used for dust control or clean up from entering any public right-of-way, storm drainage facility, or watercourse by using containment, vacuuming, absorption, or other method to remove the slurry, and dispose of slurry and containment materials properly. C. Establishment of Dryland Vegetation Due to this site being an infill project, there will be minimal disturbance in areas that will be left in a dryland vegetation state. Areas of slope grading to existing surface, and areas outside of the landscape limits that have been disturbed shall be re-seeded based on the this site’s approved Landscape Plan. In these areas, Dryland vegetation reseeding shall be installed as stated in the Notes and Specifications of the Landscape Plan. Supplemental 7 watering shall be available if needed to insure establishment in non-landscaped areas. The remainder of the areas not paved or occupied by the building will be landscaped. A copy of the Guidelines for Revegetation of Disturbed Areas is included in this report. D. Detailed Sequence of Construction Activities A sequence of construction activities chart is included with this report and copied onto the erosion and sediment control plan. E. Erosion Control Security Calculations The Calculations for Erosion and Sediment Control Escrow/Security is included with this report. The sequence is typical of the order stated on the erosion control report and drawing requirements. II. References 1. City of Fort Collins, Colorado, Erosion Control Report and Drawings Requirements Accompanying Document. 2. City of Fort Collins, Colorado, Erosion Control Report and Drawings Submittal Requirements Check Sheet. VI. APPENDIX A. Sequence of Construction Activity Mobilization Demolition Grading Utilities Installation Flat work Installation Vertical Installation Landscape Demobilization Best Management Practices (BMPs) Structural "Installation" Silt Fence Barriers* N/A N/A N/A N/A N/A N/A N/A N/A Contour Furrows (Ripping / Disking) N/A N/A N/A N/A N/A N/A N/A N/A Sediment Trap / Filter N/A N/A N/A N/A N/A Vehicle Tracking Pad* N/A N/A N/A N/A N/A N/A Flow Barriers (Wattles)* N/A N/A Inlet Filter Bags* N/A N/A N/A N/A N/A N/A N/A N/A Rock Bags* N/A N/A N/A Terracing N/A N/A N/A N/A N/A N/A N/A N/A Stream Flow Diversion* N/A N/A N/A N/A N/A N/A N/A N/A Rip Rap N/A N/A N/A N/A N/A N/A N/A N/A Collecting Asphalt / Concrete Saw Cutting Waste N/A N/A N/A N/A N/A N/A N/A *All BMPs to be Removed once Construction is Complete. Vegetative Temporary Seeding Planting Mulching/Sealant Permanent Seeding Planting Sod Installation Rolled Products : Netting/Blankets/Mats Other: SEQUENCE OF CONSTRUCTION ACTIVITY Erosion Control Report and Drawings Submittal Requirements Check Sheet JS 6/2015 Erosion Control Report Written Analysis of the site including… Current Developed Conditions Detailed and Site Specific Existing Percent Vegetation Nature and Purpose of Construction Detailed and Site Specific Total Disturbed Area (Onsite and Off) Closest Receiving Waters (Path to those waters) Rainfall Erodibility & Erosion Sediment Control Methods Analysis of Temporary & Permanent Mitigation Methods Timing (Phases) & Sequence of BMP Installation Sequence Chart …or… Separate Sheets for each sequence Choice of BMPs to minimize sediment transport Source of Non Stormwater Discharge Extra Site Data (Soil Boring/Lab Tests/Groundwater Levels) Stormwater Management Controls (SWMC) Description of all SWMC Appropriate & Priority of all SWMC Identify the SWMP Administrator Identify Potential Pollutant Sources (Identify and Describe the Means of Control) Disturbed and Stored Soils Vehicle tracking of sediment Management of contaminated soils Loading and unloading operations Outdoor storage activities Equipment maintenance and fueling Significant particulate generating Routine maintenance activities On-site waste management Concrete washing Dedicated asphalt or concrete batch plants Non-industrial waste sources (worker trash and portable toilets) Other potential spills Dry land vegetation Soil Types Seed Mixes Soil Amendments Mulches Detailed sequence of construction activities Sequence of all land disturbing activity chart Categories such as: Soil Stockpiling; Drainage Facility; Maintenance activities; Sediment basins; temporary channel stabilization; Seeding; Mulching; etc… Report Redlines have been corrected from prior submittal N/A Erosion Control Plans Clear and uncluttered plans General Location Map 22”x34” Drawing Scale 1”=1000’ to 1”=8000’ Must identify any major construction along the drainage B. Erosion and Sediment Control Escrow/Security Calculation for The City of Fort Collins Project: Disturbed Acres: 1.51 EROSION CONTROL BMPs Units Estimated Quantity Unit Price Total Price LF 1023 $2.50 $2,557.50 EA 1 $200.00 $200.00 EA 5 $200.00 $1,000.00 EA 0 $200.00 $0.00 LS 0 $500.00 $0.00 EA 1 $1,000.00 $1,000.00 EA 1 $500.00 $500.00 SF 0 $2.50 $0.00 LS 1 $1,000.00 $1,000.00 LS 1 $1,000.00 $1,000.00 LS 1 $5,000.00 $5,000.00 Sub-Total: $12,257.50 1.5 x Sub-Total: $18,386.25 Amount of security: $18,386.25 Total Acres x Price/acre: $3,020.00 $2,000.00 Sub-Total: $3,020.00 1.5 x Sub-Total: $4,530.00 Amount to Re-seed: $4,530.00 Minimum escrow amount: $3,000.00 Erosion Control Escrow: $18,386.25 Fields in yellow should be amended for this project. Rock Sock (RS) Inlet Protection Modified (IP) Scour Stop (TRM) Final Escrow Amount Erosion and Sediment Control Escrow/Security Calculation for The City of Fort Collins BMP Amount Silt Fence (SF) or Straw Waddles (SW) Vehicle Tracking Control (VTC) SWMP Administration Reseeding Amount Non-Industrial Waste Management Miniumum Escrow Amount Allied Building Products 2155 Midpoint Drive Unit Price of Seeding per acre: “The amount of the security must be based on one and one-half times the estimate of the cost to install the approved measures, or one and one-half times the cost to re-vegetate the disturbed land to dry land grasses based upon unit cost determined by the City's Annual Revegetation and Stabilization Bid, whichever is greater. In no instance, will the amount of security be less than one thousand five hundred dollars ($1,500) for residential development or three thousand dollars ($3,000) for commercial development” Inlet Protection (IP) Concrete Washout (CW) (add all other BMPs for the site in this list) On-Site Waste Management Temporary Sediment Basin (TSB) 11/19/2018 12:33 PM M:\_Golden Survey Projects\373 Allied Building Products\Reports\ABP Erosion Control Report\Example_Escrow.xls C. NRCS Soil Resource Report 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 Larimer County Area, Colorado 2155 Midpoint Drive, Fort Collins Natural Resources Conservation Service September 28, 2018 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 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 Contents Preface.................................................................................................................... 2 How Soil Surveys Are Made..................................................................................5 Soil Information for All Uses.................................................................................8 Suitabilities and Limitations for Use......................................................................8 Water Management...........................................................................................8 Surface Water Management, System............................................................8 Soil Properties and Qualities.............................................................................. 13 Soil Erosion Factors........................................................................................13 K Factor, Rock Free.................................................................................... 13 T Factor.......................................................................................................16 Wind Erodibility Index..................................................................................19 References............................................................................................................23 4 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 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 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 Soil Information for All Uses Suitabilities and Limitations for Use The Suitabilities and Limitations for Use section includes various soil interpretations displayed as thematic maps with a summary table for the soil map units in the selected area of interest. A single value or rating for each map unit is generated by aggregating the interpretive ratings of individual map unit components. This aggregation process is defined for each interpretation. Water Management Water Management interpretations are tools for evaluating the potential of the soil in the application of various water management practices. Example interpretations include pond reservoir area, embankments, dikes, levees, and excavated ponds. Surface Water Management, System The ratings for Surface Water Management, System are based on the soil properties that affect the capacity of the soil to convey surface water across the landscape. Factors affecting the system installation and performance are considered. Water conveyances include graded ditches, grassed waterways, terraces, and diversions. The ratings are for soils in their natural condition and do not consider present land use. The properties that affect the surface system performance include depth to bedrock, saturated hydraulic conductivity, depth to cemented pan, slope, flooding, ponding, large stone content, sodicity, surface water erosion, and gypsum content. The ratings are both verbal and numerical. Rating class terms indicate the extent to which the soils are limited by all of the soil features that affect the specified use. "Not limited" indicates that the soil has features that are very favorable for the specified use. Good performance and very low maintenance can be expected. "Somewhat limited" indicates that the soil has features that are moderately favorable for the specified use. The limitations can be overcome or minimized by special planning, design, or installation. Fair performance and moderate maintenance can be expected. "Very limited" indicates that the soil has one or more features that are unfavorable for the specified use. The limitations generally cannot be overcome without major soil reclamation, special design, or expensive installation procedures. 8 Numerical ratings indicate the severity of individual limitations. The ratings are shown as decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil feature has the greatest negative impact on the use (1.00) and the point at which the soil feature is not a limitation (0.00). The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as that listed for the map unit. The percent composition of each component in a particular map unit is given so that the user will realize the percentage of each map unit that has the specified rating. A map unit may have other components with different ratings. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site. Custom Soil Resource Report 9 10 Custom Soil Resource Report Map—Surface Water Management, System 4490430 4490440 4490450 4490460 4490470 4490480 4490490 4490500 4490510 4490520 4490530 4490540 4490550 4490560 4490430 4490440 4490450 4490460 4490470 4490480 4490490 4490500 4490510 4490520 4490530 4490540 4490550 4490560 496780 496790 496800 496810 496820 496830 496840 496850 496860 496870 496780 496790 496800 496810 496820 496830 496840 496850 496860 496870 40° 33' 56'' N 105° 2' 17'' W 40° 33' 56'' N 105° 2' 12'' W 40° 33' 52'' N 105° 2' 17'' W 40° 33' 52'' N 105° 2' 12'' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 30 60 120 180 Feet 0 5 10 20 30 Meters Map Scale: 1:665 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons Very limited Somewhat limited Not limited Not rated or not available Soil Rating Lines Very limited Somewhat limited Not limited Not rated or not available Soil Rating Points Very limited Somewhat limited Not limited Not rated or not available 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: Larimer County Area, Colorado Survey Area Data: Version 13, Sep 10, 2018 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Mar 20, 2015—Oct 15, 2016 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 Tables—Surface Water Management, System Map unit symbol Map unit name Rating Component name (percent) Rating reasons (numeric values) Acres in AOI Percent of AOI 64 Loveland clay loam, 0 to 1 percent slopes Somewhat limited Loveland (90%) Large rock fragments (0.02) 1.9 100.0% Totals for Area of Interest 1.9 100.0% Rating Acres in AOI Percent of AOI Somewhat limited 1.9 100.0% Totals for Area of Interest 1.9 100.0% Rating Options—Surface Water Management, System Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Custom Soil Resource Report 12 Soil Properties and Qualities The Soil Properties and Qualities section includes various soil properties and qualities displayed as thematic maps with a summary table for the soil map units in the selected area of interest. A single value or rating for each map unit is generated by aggregating the interpretive ratings of individual map unit components. This aggregation process is defined for each property or quality. Soil Erosion Factors Soil Erosion Factors are soil properties and interpretations used in evaluating the soil for potential erosion. Example soil erosion factors can include K factor for the whole soil or on a rock free basis, T factor, wind erodibility group and wind erodibility index. K Factor, Rock Free Erosion factor K indicates the susceptibility of a soil to sheet and rill erosion by water. Factor K is one of six factors used in the Universal Soil Loss Equation (USLE) and the Revised Universal Soil Loss Equation (RUSLE) to predict the average annual rate of soil loss by sheet and rill erosion in tons per acre per year. The estimates are based primarily on percentage of silt, sand, and organic matter and on soil structure and saturated hydraulic conductivity (Ksat). Values of K range from 0.02 to 0.69. Other factors being equal, the higher the value, the more susceptible the soil is to sheet and rill erosion by water. "Erosion factor Kf (rock free)" indicates the erodibility of the fine-earth fraction, or the material less than 2 millimeters in size. Custom Soil Resource Report 13 14 Custom Soil Resource Report Map—K Factor, Rock Free 4490430 4490440 4490450 4490460 4490470 4490480 4490490 4490500 4490510 4490520 4490530 4490540 4490550 4490560 4490430 4490440 4490450 4490460 4490470 4490480 4490490 4490500 4490510 4490520 4490530 4490540 4490550 4490560 496780 496790 496800 496810 496820 496830 496840 496850 496860 496870 496780 496790 496800 496810 496820 496830 496840 496850 496860 496870 40° 33' 56'' N 105° 2' 17'' W 40° 33' 56'' N 105° 2' 12'' W 40° 33' 52'' N 105° 2' 17'' W 40° 33' 52'' N 105° 2' 12'' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 30 60 120 180 Feet 0 5 10 20 30 Meters Map Scale: 1:665 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons .02 .05 .10 .15 .17 .20 .24 .28 .32 .37 .43 .49 .55 .64 Not rated or not available Soil Rating Lines .02 .05 .10 .15 .17 .20 .24 .28 .32 .37 .43 .49 .55 .64 Not rated or not available Soil Rating Points .02 .05 .10 .15 .17 .20 .24 .28 .32 .37 .43 .49 .55 .64 Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Table—K Factor, Rock Free Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 64 Loveland clay loam, 0 to 1 percent slopes .20 1.9 100.0% Totals for Area of Interest 1.9 100.0% Rating Options—K Factor, Rock Free Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Layer Options (Horizon Aggregation Method): Surface Layer (Not applicable) T Factor The T factor is an estimate of the maximum average annual rate of soil erosion by wind and/or water that can occur without affecting crop productivity over a sustained period. The rate is in tons per acre per year. Custom Soil Resource Report 16 17 Custom Soil Resource Report Map—T Factor 4490430 4490440 4490450 4490460 4490470 4490480 4490490 4490500 4490510 4490520 4490530 4490540 4490550 4490560 4490430 4490440 4490450 4490460 4490470 4490480 4490490 4490500 4490510 4490520 4490530 4490540 4490550 4490560 496780 496790 496800 496810 496820 496830 496840 496850 496860 496870 496780 496790 496800 496810 496820 496830 496840 496850 496860 496870 40° 33' 56'' N 105° 2' 17'' W 40° 33' 56'' N 105° 2' 12'' W 40° 33' 52'' N 105° 2' 17'' W 40° 33' 52'' N 105° 2' 12'' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 30 60 120 180 Feet 0 5 10 20 30 Meters Map Scale: 1:665 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons 1 2 3 4 5 Not rated or not available Soil Rating Lines 1 2 3 4 5 Not rated or not available Soil Rating Points 1 2 3 4 5 Not rated or not available 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: Larimer County Area, Colorado Survey Area Data: Version 13, Sep 10, 2018 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Mar 20, 2015—Oct Table—T Factor Map unit symbol Map unit name Rating (tons per acre per year) Acres in AOI Percent of AOI 64 Loveland clay loam, 0 to 1 percent slopes 3 1.9 100.0% Totals for Area of Interest 1.9 100.0% Rating Options—T Factor Units of Measure: tons per acre per year Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Lower Interpret Nulls as Zero: No Wind Erodibility Index The wind erodibility index is a numerical value indicating the susceptibility of soil to wind erosion, or the tons per acre per year that can be expected to be lost to wind erosion. There is a close correlation between wind erosion and the texture of the surface layer, the size and durability of surface clods, rock fragments, organic matter, and a calcareous reaction. Soil moisture and frozen soil layers also influence wind erosion. Custom Soil Resource Report 19 20 Custom Soil Resource Report Map—Wind Erodibility Index 4490430 4490440 4490450 4490460 4490470 4490480 4490490 4490500 4490510 4490520 4490530 4490540 4490550 4490560 4490430 4490440 4490450 4490460 4490470 4490480 4490490 4490500 4490510 4490520 4490530 4490540 4490550 4490560 496780 496790 496800 496810 496820 496830 496840 496850 496860 496870 496780 496790 496800 496810 496820 496830 496840 496850 496860 496870 40° 33' 56'' N 105° 2' 17'' W 40° 33' 56'' N 105° 2' 12'' W 40° 33' 52'' N 105° 2' 17'' W 40° 33' 52'' N 105° 2' 12'' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 30 60 120 180 Feet 0 5 10 20 30 Meters Map Scale: 1:665 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons 0 38 48 56 86 134 160 180 220 250 310 Not rated or not available Soil Rating Lines 0 38 48 56 86 134 160 180 220 250 310 Not rated or not available Soil Rating Points 0 38 48 56 86 134 160 180 220 250 310 Not rated or not available 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 Table—Wind Erodibility Index Map unit symbol Map unit name Rating (tons per acre per year) Acres in AOI Percent of AOI 64 Loveland clay loam, 0 to 1 percent slopes 48 1.9 100.0% Totals for Area of Interest 1.9 100.0% Rating Options—Wind Erodibility Index Units of Measure: tons per acre per year Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Custom Soil Resource Report 22 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 23 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 24 D. Guidelines for Revegetation of Disturbed Areas GUIDELINES FOR REVEGETATION OF DISTURBED AREAS I. GENERAL: Re-seeding of disturbed areas to establish a viable vegetative cover is often the most effective method for long-term control of erosion. Proper selection of species to be used will maximize the success of the project. In most of the outlying areas of the County, selection of appropriate native grasses is recommended. Introduced species, such as smooth brome and crested wheat, are not recommended unless the area to be re-seeded is in an area of the county that is dominated by such species. This could be in areas where introduced aggressive pasture grasses have been established and are likely to replace other species over time. Appropriate species for the seed mix should be determined by a knowledgeable specialist after adequate reconnaissance and inventory of the site. Species selection for sites in areas under the jurisdiction of other agencies, such as U.S. Forest Service, Colorado State Forest, or BLM, should be done in consultation with the agency involved. The specialist should also specify appropriate mulching and soil amendment parameters for the re-seeded areas. II. TOPSOIL: Retention of topsoil, when a site is to be disturbed, is perhaps the most critical aspect of site reclamation. It is also the initial step to be accomplished when the work begins. Topsoil is the uppermost horizon of soil and contains organic material which often gives it a dark brown color. In addition to the organic matter, topsoil contains nutrients, microbes and a seed bank from the plants existing at the site. If these can be saved and replaced when the work is done, the chances of a successful re-establishment of vegetative cover is enhanced manifold. The following guidelines will optimize the topsoil retention and redistribution processes when areas are disturbed during the course of typical projects. 1) Storage: Topsoil should be removed and stockpiled whenever practical for redistribution over the disturbed area to provide a viable seedbed. This can be accomplished by removing the topsoil and storing in piles on the perimeter of the area to be disturbed or wind rowing the topsoil along the outside edge of areas such as road cuts. The topsoil can then be redistributed over the disturbed areas in preparation for seeding activities. When 1 soil is to be stockpiled for a period exceeding six months, the stockpile should be seeded to appropriate grasses. This will protect the soil from erosion and will maintain the existing microorganisms and other soil constituents through natural nutrient cycling processes. 3) Redistribution: Clean, uncontaminated topsoil should be reapplied to a depth of 4-6 inches. Soil replacement will minimize the need for soil amendments and the seed will be placed in an optimum medium for germination and establishment. If topsoil stockpiling is not possible, or is insufficient to attain the 4-6 inch depth, the material to be used as soil should be amended to replace organic material, nutrients and other soil characters as needed. Composted manure, fertilizers, and other amendments, as prescribed by the Specialist, should be applied and incorporated into the top 6 inches of material. In all cases adequate sampling should be accomplished for soil testing at the Colorado State University Soils Lab or a laboratory of comparable capabilities. Recommendations for soil amendments are reported with the results and should be followed. To insure proper recommendations are received, it is necessary to describe the type of seeding application intended (eg: native range grasses, cereal crops, irrigated pasture grasses, etc.) when presenting the soil samples for analysis. 3) Soil sampling: A composite sample should be collected for analysis using a spade or soil auger. No galvanized tools should be used. Sampling tools should be clean and free of rust. The composite should combine no fewer than three subsamples taken from the top 6 inches of soil material. The number of composite samples will depend upon the size of the area and homogeneity of soil material. Appropriate number of samples should be determined by the Specialist. If more than one composite is collected, the location of areas represented should be recorded and marked in the field. A composite sample should contain approximately one quart of material for analysis. The sample should be placed in a clean one quart polyethylene bag and sealed. Samples must be delivered to the lab within 24 hours of collection if at all feasible. If samples cannot be delivered within 24 hours, the sample should be air-dried for 48 hours in a dust free environment. III. FERTILIZER RECOMMENDATIONS: Fertilizers should be added only to the extent necessary. Native grasses are adapted to soils with low nutrient content and often require minimal fertilization to do well. If sufficient topsoil is stockpiled and redistributed, it will often retain adequate amounts of nutrients and microbes for good seed germination and establishment of native range grasses. Native grasses respond best to slow-release organic fertilizers, such as Biosol™ or an equivalent, and these are preferred for soil amendment in cases where native species are seeded. Over application of commercial fast-release fertilizers will encourage weed growth in these applications. If a commercial fertilizer is to be used, its formula should be based upon analysis of the existing soil or growing medium. This analysis can be accomplished by sampling the soil to be seeded and having it analyzed for nutrient composition by a qualified lab. If this is not possible, 11-48-0 commercial fertilizer is recommended. V. SEED BED PREPARATION: 2 The soil to which the seeds are to be applied should be in a firm condition, but not so firm or compacted as to inhibit infiltration. Loose soils may require light rolling. If the surface is compacted to the point to inhibit infiltration, the top 4-6 inches should be harrowed or tilled before rolling. The intent is to accommodate seeding to proper depth and to provide sufficient infiltration of precipitation for soil storage of moisture and to decrease runoff and erosion. On slopes, harrowing along contours should be accomplished to slow runoff and promote infiltration. Depth of harrowing or tilling should be determined by depth of topsoil applied and should be set to minimize intermixing of this topsoil layer and the underlying subsoil or spoil material. V. METHODS OF SEEDING: Seeds must be placed at the appropriate depth in the soil to optimize germination. In general, seeds should be placed ¼” to ½” deep in the soil. There are several acceptable methods to accomplish efficient seeding on disturbed sites. 1. Drill Seeding: Drill seeding is normally considered to be the most efficient and effective seeding procedure. Seed should be drilled to a depth of ¼” to ½” in depth. Drill seeding is very effective and economic on large relatively flat areas (up to 3:1 slope). Drilling depths should be determined by recommended depths for the species selected for the project mix. 2. Hand/Mechanical Broadcast Seeding: Hand or mechanical broadcast seeding can be very effective, with proper technique, and is more practical and economic for small or hard to reach areas. The seedbed is tilled or harrowed prior to seeding. After broadcasting the seed, the seedbed should be lightly harrowed or chain dragged to fully incorporate the seed with the soil. Seeding rates shall be double the recommended drill-seeding rate. 3. Hydro-seeding: Hydro-seeding is an efficient means of applying seed to steep areas (>3:1). This method has the disadvantage of a less effective means of achieving proper soil to seed contact. The operation should be done as a separate operation from hydro-mulching, although it is acceptable to add a small amount of mulch in the seed slurry to bind to the soil and allow visible evidence of covered areas. Seeding rates should be double the recommended drill-seeding rate. VI. MULCHING: Upon completion of seeding and fertilizing operations, mulch should be applied to the soil surface. Mulch will deter erosion during the establishment of vegetation and will serve to conserve moisture and reduce surface compaction or crusting. The following mulching techniques are acceptable: 3 1. Crimped straw or hay: The material should be native grass hay or cereal grain straw. Native hay should be certified weed free. At least 50 percent of the mulch, by weight, should be ten inches or more in length. Hay or straw is crimped in place with a mechanical crimper made for such purposes or using a farm-type disc plow set straight with adequate weight to crimp the material to a depth of approximately 4 inches. The hay or straw should be applied at a minimum rate of 2000 lbs. per acre. Slopes exceeding 5:1 or areas where windy conditions are likely should be mulched at 4000 lbs. per acre. 2. Hydro-mulch: Hydro-mulch, comprised of wood fiber, should be applied at a rate of 1000 to 2000 lbs. per acre, depending on slope conditions. Hydro-mulching should be limited to areas that exhibit slopes too steep to allow safe operation of drill-seeding equipment or are otherwise inaccessible to other means. Slopes greater than 3:1 require addition of tackifying agents to the slurry to maximize retention of the mulch on the soil surface. These agents should be mixed as per manufacturers’ specifications to achieve the desired coverage for the topography of the site. 3. Erosion control blankets: Erosion control blankets should be used in conditions where steep slopes (>3:1) with relatively smooth surface soil surface are encountered or areas where concentrated flows are expected, such as drainage channels. These blankets come in a number of configurations and weights. Manufacturer’s specifications should be consulted for appropriate application. These blankets are to be adequately anchored in place with staples as per manufacturers’ specifications. Blankets are not effective on rough, uneven or rocky surfaces since adequate continuous contact with the soil cannot be attained. 4. Bonded Fiber Matrix Systems: In cases where rough, uneven, or rocky surfaces preclude the use of blankets, a bonded fiber matrix system should be specified. These systems involve the hydraulic application of a fiber and tackifier mulch in a continuous cover and are very effective on steep slopes if properly applied. Manufacturers’ specifications shall be consulted for the appropriate application rate for the site circumstances. VII. SEED MIX SPECIFICATIONS: Larimer County is divided into three distinct areas of topography and climatic conditions (Figure 1). Area I consists of flatlands, Area II consists of the foothills area, and Area III the mountainous areas of the County. The tables attached illustrate native grass species that are best adapted to each particular area. Seed mixes should be comprised of choices from the appropriate table for the site to be seeded. Seed mixes should be designed to accomplish an application rate of 65 seeds per square foot, on a PLS* basis. A minimum of four species should be specified for mixes and a mix of cool and warm weather species used if possible. A standard mix is shown for each area as well as other representative grasses. Substitutions or * PLS = Pure Live Seed (percentage of live seed per unit calculated by multiplying the germination rate (in %) by the purity % for each species. 4 additions to the standard mix should come from this list. It should be noted that the seeding rates from the tables are for drill seeding specifications. Broadcast seeding or hydraulic seeding rates should be specified at twice this rate to assure proper germination rates. Custom mixes may be appropriate for localized projects. Instances may be in areas within U. S. Forest Service jurisdiction or other sensitive areas where use of appropriate native species, particular to that area, is mandatory or desired. Such mixes should be designed by the Specialist or other knowledgeable party to meet the criteria. For added interest or a more “naturalized” plant establishment, wildflowers and other native forbs may be added. Some species of native wildflowers are easily established and perennial species will establish extensive root systems that enhance erosion control and soil stabilization. A few native wildflower species are suggested in the tables and can be added to the seed mix. VII. SLOPE CONFIGURATION AND PREPARATION: Cut and fill slopes should be designed and constructed to maximize stability and optimize conditions for reseeding as much as is practical. In general, cut slopes in soil or loose material should be constructed to be no steeper than 3:1 unless site constraints limit this configuration. Fill slopes should be no steeper than 3:1. All slopes should be scarified along contours for the final dressing to retard erosion and optimize seed placement. Tracking with dozers, or other tracked equipment, up and down slopes is acceptable placing cleat marks parallel to contours. Blading up and down slopes is not acceptable for final dressing of the slope. On slopes where regular farm equipment can be used safely, harrowing of the surface along contours is an excellent method. The surface should be left in a slightly roughened condition with harrow or cleat marks along contours. Seeding operations should be completed as soon as possible to stabilize the surface while the soil is still in optimum condition to accept seed, amendments and mulch. If seasonal conditions are inappropriate for seeding, the slope may require interim mulching to control erosion until the proper conditions exist for successful seed placement. VIII. ROAD-SIDE STORM WATER CHANNELS: Reconstruction or regrading of roadside channels is an integral part of most projects in which the Engineering Department is involved. Timely revegetation of these channels is critical for the ongoing viability of these channels as conduits for storm water. By definition, roadside storm water channels are often submitted to concentrated flows that make it a challenge to establish adequate grass cover to optimize control of erosion and to prevent sedimentation of the storm water flows. It is important to protect the soil surface of the channel adequately for a time sufficient to allow germination and establishment of the seeded grasses. Geometry of the channel should be designed and constructed to maintain side slopes of no greater than 3:1 if at all possible. In cases where continuous flows are anticipated, or intermittent large flows are likely during the establishment period, the bare soil should be adequately mulched or covered with appropriate erosion control blankets after seeding. If hydro mulch is used, it should be applied at 3,000 lb/ac with tackifier added at the manufacturer’s recommended rate. It is often advisable to cover the bottom and sides of the channel, at least to the anticipated high-water 5 flow, with blankets. Composition and construction of specified erosion control blankets will depend upon geometry of the channel and expected flow rates. Manufacturer’s specifications should be consulted to determine the appropriate weight and composition of the blankets. Manufacturer’s installation instructions for the proper staple pattern, overlap and blanket placement should be followed. Details of installation should be included in the plans if the contractor is expected to install the blankets. Installation should be monitored and inspected to insure correct application. To repeat, quick establishment of grass cover is often critical in these situations. Although the native species mixes detailed in the tables attached are often preferable or mandated in certain areas, additions of species noted for quick establishment may be necessary to stabilize the soil. In many of the plains locations the surrounding area may be predominantly pasture or farmland. In these cases it is appropriate to seed the channel to species such as smooth brome or tall fescue for quick establishment and vigorous growth. Seed at the rate of 30 lb/ac, PLS. In other areas, where native seeding is preferred, addition of annual ryegrass or hard fescue may be appropriate. In these cases the species should make up about 10-15% of the total mix. If circumstances preclude use of non-native species in the mix, other mechanical or chemical means of soil stabilization will be necessary to allow sufficient time for seed germination and establishment of the grass. This could mean installation of erosion control blankets or addition of chemical additives to maintain a stable soil matrix for at least a year. 6 AREA I -Flatlands Standard Mix: Species Scientific name Variety % of mix lb/ac, PLS Buffalograss Buchloe dactyloides Texoka 44.4 8.4 Western wheatgrass Pascopyrum smithii Arriba 22.8 4.3 Slender wheatgrass Elymus trachycaulus San Luis 15.9 3.0 Sideoats grama Bouteloua curtipendula Vaughn 13.2 2.5 Blue grama Bouteloua gracilis Hachita 3.2 0.6 Sand dropseed Sporobolus cryptandrus 0.5 0.1 Seeding rate =18.9 lb/ac, PLS Representative species: Species Scientific name Seeds per pound Slender wheatgrass Elymus trachycaulum 159,000 Western wheatgrass Pascopyrum smithii 110,000 Blue grama Bouteloua gracilis 825,000 Buffalograss Buchloe dactyloides 56,000 Sideoats grama Bouteloua curtipendula 191,000 Little bluestem Schizachyrium scoparium 260,000 Sand bluestem Andropogon hallii 113,000 Sand dropseed Sporobolus cryptandrus 5,298,000 Green needlegrass Stipa viridula 181,000 Alkali sacaton* Sporobolus airoides 1,758,000 Inland saltgrass* Distichlis stricta 520,000 Switchgrass* Panicum virgatum 389,000 *Species adapted to wet, alkaline habitat Wildflower species: Yarrow Prairie coneflower Perennial gaillardia Plains coreopsis Blue flax Plains wallflower Lance-leaved coreopsis Prairie aster Scarlet globemallow Annual gaillardia 7 AREA II - Foothills Standard Mix: Species Scientific name Variety % of mix lb/ac, PLS Western wheatgrass Pascopyrum smithii Arriba 30.1 4.3 Big bluestem Andropogon gerardi Pawnee 25.2 3.6 Green needlegrass Stipa viridula Lodorm 18.2 2.6 Sideoats grama Bouteloua curtipendula Vaughn 17.5 2.5 Sheep fescue Festuca ovina Covar 4.8 0.7 Blue grama Bouteloua gracilis Hachita 4.2 0.6 Seeding rate = 14.3 lb/ac, PLS Representative species: Species Scientific name Seeds per pound Western wheatgrass Pascopyrum smithii 110,000 Bluebunch wheatgrass Pseudoroegneria spicatum 140,000 Green needlegrass Stipa viridula 181,000 Needle and thread Stipa comata 115,000 Big bluestem Andropogon gerardi 130,000 Little bluestem Schizachyrium scoparium 260,000 Sheep fescue Festuca ovina 680,000 Sandberg bluegrass Poa sandbergii 925,000 Canby bluegrass Poa canbyi 926,000 Indian ricegrass Oryzopsis hymenoides 141,000 Blue grama Bouteloua gracilis 825,000 Sideoats grama Bouteloua curtipendula 191,000 Wildflower species: Pasque flower Indian paintbrush Perennial gaillardia Blue flax Yarrow Penstemon spp. Sulphur flower Harebell Plains wallflower Low fleabane 8 AREA III - Mountains Standard Mix: Species Scientific name Variety % of mix lb/ac, PLS Mountain brome Bromus marginatus Bromar 33.1 5.2 Western wheatgrass Pascopyrum smithii Arriba 27.4 4.3 Slender wheatgrass Elymus trachycaulus San Luis 19.2 3.0 Annual ryegrass* Lolium multiflorum 12.7 2.0 Sheep fescue Festuca ovina Covar 4.4 0.7 Canby bluegrass Poa canbyi Canbar 3.2 0.5 Seeding rate = 15.7 lb/ac, PLS *Introduced species for quick cover. May not be acceptable in special areas. Representative species: Species Scientific name Seeds per pound Mountain brome Bromus marginatus 90,000 Canby bluegrass Poa canbyi 926,000 Sheep fescue Festuca ovina 680,000 Slender wheatgrass Elymus trachycaulus 159,000 Western wheatgrass Pascopyrum smithii 110,000 Sandberg bluegrass Poa sanbergii 925,000 Bluebunch wheatgrass Pseudoroegneria spicata 140,000 Prairie junegrass Koleria cristata 2,315,000 Idaho fescue Festuca idahoensis 450,000 Alpine bluegrass Poa alpina 1,000,000 Timothy Phleum pratense 1,300,000 Blue grama Bouteloua gracilis 825,000 Wildflower species: Pasque flower Yarrow Bellflower Fleabane daisy Arrowleaf balsa Dame’s rocket Colorado blue columbine Penstemon spp. Wallflower Rocky Mountain iris 9 NON-NATIVE SEEDING OF ROADSIDE DITCHES IN PLAINS AND FOOTHILLS AREAS* Species Scientific name % of Mix, PLS Lb/ac, PLS Smooth brome Bromus inermis 41 12.4 Tall fescue, Grande Festuca arundinacea 21 6.3 Western wheatgrass Pascopyrum smithii 21 6.3 Annual ryegrass Lolium multiflorum 17 5.0 30.0 * This seed mix is appropriate where quick germination and establishment are important and native seeding is not an issue (e.g., areas in agricultural settings where introduced pasture grasses are common). 10 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: Larimer County Area, Colorado Survey Area Data: Version 13, Sep 10, 2018 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Mar 20, 2015—Oct 15, 2016 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 21 15, 2016 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 18 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: Larimer County Area, Colorado Survey Area Data: Version 13, Sep 10, 2018 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Mar 20, 2015—Oct 15, 2016 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 15 11 Ditches, Extended Detention, Culverts, Storm sewers… Basins Divided into Topography Erosion Control Plans 22”x34” Drawing Scale 1”=20’ to 1”=200’ Sequence Plans indicating timing, extent and location, of the temporary BMPs Standard construction details and notes of erosion and sediment control measures Job-specific construction details and notes of erosion and sediment control measures List vegetative specification from either Urban Drainage Manual, or alternative sources. List structural specification from the Urban Drainage Manual, or other specifications and a justification if an alternative is sought after. A construction detail for ALL proposed construction BMPs. The ‘standard erosion and sediment control notes’ are included on the plan set. Plan Redlines have been corrected from prior submittal N/A Erosion control security calculations BMP Amount Calculated All BMPs Calculated Estimated Quantity and Price are realistic 1.5 Times the estimated BMP controls Reseeding Amount Calculated All Disturbed Area Calculated Estimated Area and Price are realistic 1.5 Times the estimated reseeding Higher of the BMP, Reseeding, or Minimum Selected (Final Erosion Control Number needs to be sent to City Engineer for the Project in order to be reflected in the Development Agreement) Escrow Redlines have been corrected from prior submittal N/A