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HomeMy WebLinkAboutAstera Parachute Phase 1 Clearing grading geo weed Narrative ASTERA PARACHUTE PROJECT NARRATIVE PHASE 1 4111 6 HWY, Parachute Parcel Number 2409-331-00-002 Project Description Installation of a Solar Photo Voltaic array on the northwest 0.67 acres of the 5.2-acre lot. Consisting of 934 panels 535W each with a total maximum output of 499,690W. The panels are 7.5’ x 3.7’ each and will use a ballast system. No boring, or permanent structures will be constructed to mount the system. The ballasts will be designed for 115mph wind load and 40 lbs snow load. The array will not be interconnected with the existing Xcel power grid. The area will be de-brushed and cleared Ballasts will rest on the existing topo. Some leveling is expected to fill wheel ruts, and divots and to remove any large rocks. Less than 20,00 sqft and under 5000 cubic yards. SEE SITE PLAN: Astera Parachute Site Plan & Existing Topo Initial Investigation and Site Condition. July 11, 2024 Preliminary site visit. Property Description: The lot is located at 4111 6 HWY Garfield County Colorado. It lies South East of the I70 freeway and borders on the South West by a I70 Drainage and access easement, the South East property line is the Highway 6 and 24 ROW, the North East property line Parallels a wash, and the industrial complex road Named Fox?. The property is moderately covered in brush and some grass. Access is from the industrial park to the east. The North West property line. Found Pin labeled I70 ROW (LS24318) on the North corner of the property a I70 fence runs South West N49°E along the property line approx. 557.8 ft to a found Pin labeled I70 ROW (LS24318) then South East N65°W 223.2 ft to the beginning of a curve following the I70 Drainage and access easement, arc length 413.3 ft to a found Pin labeled I70 ROW. No pin was located for the easternmost property corner. The South East property line, however, is S55°W 238.09 ft and the North East property line is S34°E 605.6 ft returning to the North corner Pin. In addition to the I70 ROW and the Highway 6 and 24 ROW, there are two powerlines running through the property. The first of which, is on the North West property line. The other large transmission line runs through the top third of the property paralleling the North West property line. It has one large steel pole in the middle of the northern 1/3 of the lot. There exists a wash adjacent to the east property line. There are two driveways that cross this wash to access the property. Each driveway has a 3 ft diameter culvert. This wash starts at the I -70 embankment and a 3 ft culvert. GPS Survey data collected was compared to the legal description obtained from Garfield County Recorder CADASTRAL (17066) Book 590/643 and is consistent with that document. The average elevation observed by the GPS data is 5040 feet, which correlates well with the Garfield County GIS. Property History 1278 19 Road, Fruita Colorado 81521 Phone 970-250-3502 No history of construction permits is available and there is no evidence of former structures on the lot. The property seems to have been vacant since at least 1959. No attempt at farming is indicated. Purchase document history: 12-13-2023 Silt Energy Development LLC Purchase from UNA DEVELOPMENT LLC Receipt # 992092. Account R460073 Garfield County. 02/01/2022 UNA DEVELOPMENT LLC purchase from STRONG, JOHN E Receipt # 970360 Garfield County.. 04-23-2019 Public Service of Colorado 20’ Utility Easement for Electric Power transmission on the property owner John E. Strong northern property line. Recorded Receipt # 919507 Garfield County. 09-02-2014 Access easement dedicated from the Travelers Highlands Subdivision PID to Property owner John E. Strong. Recorded Receipt #853319 09/05/2014 Garfield County. 04-07-1995 STRONG, JOHN E purchase from ANVIL POINT PROPERTIES LTD Receipt #476423 Garfield County. 01-19-1982 Resolution COMMISSIONERS-GARFIELD COUNTY 01-13-1982 L G EVERIST INC purchase from ANVIL POINTS PROPERTIES LTD Receipt # 323649 Garfield County. 06-06-1959 KENDRICK HAROLD H purchased from ESHE ANNIE H Receipt # 205669 Garfield County. Geologic Hazard and Soil Evaluation. Scope of Investigation. 1, Conduct a surface condition, existing vegetation investigation, and a percolation test to evaluate the conditions at the site. 3, Develop recommendations for: Clearing and Grading the property. Calculated stormwater absorption and runoff Surface prep for Ballast-type solar structures and driveway. 4, Evaluate and report potential geologic hazards at the site. Proposed Usage. Install Ballast mount solar array. Site Conditions The property is on alluvium created from the decay of the Book Cliffs, Torriorthents-Camborthids-Rock outcrop complex, steep. NRCS Soil data indicates 64.6% Arvada Loam, 1 to 6% slopes, and 35.4% Arvada Loam 6 to 20% slopes. Arvada Loam is Highly saline alluvium derived from sandstone and shale. Typical profile • H1 - 0 to 3 inches: loam • H2 - 3 to 17 inches: silty clay loam • H3 - 17 to 60 inches: silty clay loam Properties and qualities • Slope: 1 to 6 percent • Depth to restrictive feature: More than 80 inches • Drainage class: Well drained • Runoff class: High • Capacity of the most limiting layer to transmit water (Ksat): Moderately low to moderately high (0.06 to 0.20 in/hr) • Depth to water table: More than 80 inches • Frequency of flooding: None • Frequency of ponding: None • Calcium carbonate, maximum content: 10 percent • Gypsum, maximum content: 2 percent • Maximum salinity: Slightly saline to strongly saline (4.0 to 16.0 mmhos/cm) • Sodium adsorption ratio, maximum: 30.0 Arvada Loam Development Rating: -Solar Arrays Soil Anchored: Shrink-swell rating of 1.00 and a rating of “Very Limited”, Low Strength -Solar Arrays Ballast Anchored: Very Limited, Low Strength 1.00. See Appendix C for the rating Description. Hazards and Limitations: -Unpaved Local Roads and Streets: Somewhat limited. Aggregation Method: Dominant Condition. Low strength 0.73. -Landscape: Somewhat limited. Aggregation Method: Dominant Condition. Drainage The lot slopes to the south with an average slope of 1.3%. As shown on the Site Plan. There exists a wash adjacent to the east property line. Two driveways cross this wash to access the property. Each driveway has a 3 ft diameter culvert. This wash starts at the I -70 embankment and a 3 ft culvert. No other ditches catch ponds culverts or any other runoff apprentices are in place on the lot. From the soil properties and testing the area does not generate runoff. Alterations on this property adding impervious surfaces will create concentrations of runoff. This will be contained on-site. Therefore, the improvements proposed for this site will not alter the existing stormwater flows off this property. Storm Water Drainage The lot slopes to the southwest with an average slope of 1.3%. The capacity for absorption has been calculated based on soil data from the NRC and on-site soil evaluation and testing. Flood Irrigation is not permitted nor is it available on this lot. Storm Water Runoff Appendix B, Rainfall Values for the Parachute Area, gives an average of .13 inches per hour based on a 100-year 24-hour storm event. From Appendix A Perk Test results the lowest infiltration rate for the surface test holes, Post Soak, is 16.2 inches per hour. This value is much greater than the Rain Event Value. - The infiltration rate of the surface soil exceeds the precipitation rate. Drainage Recommendations -Slope grade away from the structure to sufficiently protect the footing as designed. 1:12 for dirt and .5:12 for pavement Min. -After the site is cleared and graded. It should be vegetated with native grass to provide dust and weathering protection. -the upper section of the wash adjacent to the east property line should be riprapped on the property side of the wash from the northeast property pin to the first driveway culvert to prevent future washout into the lot. Material Specification: -Concrete Exposed to weather: FC 3500 PSI @ 28 Days -Concrete Unexposed to weather, FC 3000 PSI @ 28 Days -Cement: Type II or Type II-V no Calcium Chloride added -Aggregate ASTM C33 -Reinforced Steel: ASTM A615 Grade 40 -Anchor Bolts A-307 Reinforcing Steel: -Reinforcing steel to be D formed bars conforming to SSTM A616, grade 60 -Unless otherwise noted cover on reinforcing steel shall be: 1-1/2” all flat work surfaces 3” on all formed footings -Reinforcing bars shall be continuous or overlapped a min. of 37”for contact joints, and 15” for noncontact joints. -Welding bar is allowed on 707 re-bar -Miscellaneous steel shall conform to ASTM A82 -No direct contact from the native soil to the reinforcing bar embedded in concrete is allowed. Any support ties must be isolated from reinforcing steel. Driveways -Arvada Loam soils have low strength, some frost action, and the potential for shrink-swell. They are very limited for direct use as a road. The area should be scarfed 9 to 12 inches moisture conditioned, and compacted. inches of road base, Class 6, should be placed in maximum 6-inch loose lifts, moisture conditioned, and compacted -For long-term stability of the road provide positive drainage away from the pavements. Crown road for runoff. Avoid ponding on or near the road. Notes and Conclusions These recommendations are based on investigation results of surface conditions and experience working in this general location. This report is valid only for the specified area in this document. All recommendations in this document should be followed to provide stable and long-lasting improvements and to reduce the risk of weathering. It is impossible to predict long-term changes in subsurface moisture conditions and/or the precise magnitude or extent of any volume change in the native soils. Where significant increases in subsurface moisture occur due to poor grading, improper stormwater management, utility line failure, excess irrigation, or any other cause, during or after construction, significant movements are possible. All construction of slabs, foundations, roadways, drainage, etc should be inspected and overseen by the engineer or an affiliate to ensure conformance to the recommendations of this report. The initial site investigation and soil research show that development on this property will need special attention. Soil treatment, Grading, Water control, Foundation design, and solar anchoring systems will all need to be designed to minimize the potential for failure of the structures. Weed Management: The property has been evaluated for existing Vegetation and Noxious Weeds. The following vegetation was identified on he property: Current Noxious Weeds on the Garfield County Website as od Sept 2024. The site to be evaluated annually for these plants: List A with more than 10 populations in colorado: Cypress spurge, Euphorbia cyparissias Mediterranean sage, Salvia aethiopis Myrtle spurge, Euphorbia myrsinites Purple loosestrife, Lythrum salicaria List B: Absinth wormwood, Artemisia absinthium Black henbane, Hyoscyamus niger, Bouncingbet, Saponaria officinalis Bull thistle, Cirsium vulgare Canada thistle, Cirsium arvense Chinese clematis, Clematis orientalis Chicory – cichorium intybus Corn chamomile – anthemis arvensis Astera Parachute Project - Vegitation 9/13/2024 4111 6 Hwy Parachute Co. Plants existing and identified on the property Name Amount Discription Uses Hoary tansyaster, (Machaeranthera canescens) Sparce Sunflower family (Asteraceae). Hoary tansyaster is a short-lived perennial forb with pale to dark purple flowers Revegitaion, Ethnobotanical Plants were used by Navajo Indians for nose and throat troubles Narrow Leaf yucca, (Yucca harrimaniae) Sparce is native to the southwestern US where it can be found growing on plateaus, on hillsides and rocky outcrops. Fibers from the leaves is used for making ropes, mats and baskets. The leaves can be used as a paint brush or broom. The roots are used to make a soap. Gutierrezia sarothrae, (broom snakeweed) Sparce It is a subshrub native to much of the western half of North America, and can be found in a number of arid, grassland, and mountain habitats. It can be toxic to livestock in large quantities, due mainly to the presence of saponins The Comanche bound the stems together to make brooms. The Blackfoot used the roots in an herbal steam as a treatment for respiratory ailments. shadescale SaltBush, (atriplex confertifolia)Sparce Shadscale saltbush is a low growing shrub (1-3 ft) with spine tipped branches. Shadscale saltbush is dioecious (separate male and female plants). The Gosiute and Hopi used the leaves of shadscale saltbush to be eaten as greens or to be cooked with meal to make a pudding Big Sagebrush, (Artemisia tridentata)Moderat Big sagebrush is a coarse, many-branched, pale-grey shrub with yellow flowers and silvery-grey foliage, which is generally 0.5–3 metres (1+1⁄2–10 feet) tall. large quantities of sagebrush seed ground it to make flour. The main modern use is as firewood, with the wood's oils being particularly flammable.[24 Rubber Rabbitbrush, (chrysothamnus nauseosus) Moderat Rubber rabbitbrush is highly variable, with several different subspecies located throughout the western United States. Native Americans reportedly used rabbitbrush as a yellow dye, to make a medicinal tea, and for chewing gum. important browse species for mule deer, pronghorn, and jackrabbits during fall and winter. Juniper Tree, (Juniperus osteosperma)Sparce Common juniper is a native, evergreen shrub or columnar tree Clump Grass Moderate Noxious Plants identified on the property No Noxious weed from List A were encountered No Noxious weed from List B were encountered Common burdock – arctium minus Curly dock – rumex crispus Common tansy, Tanacetum vulgare Common teasel, Dipsacus fullonum Cutleaf teasel, Dipsacus laciniatus Dalmatian toadflax, Linaria dalmatica & genistifolia Dame's rocket, Hesperis matronalis Diffuse knapweed, Centaurea diffusal Hoary cress, Lepidium draba Houndstongue, Cynoglossum officinale Jointed goatgrass, Aegilops cylindrica Leafy spurge, Euphorbia esula Mayweed chamomile, Anthemis cotula Meadow knapweed – centaurea x moncktonii Musk thistle, Carduus nutans Oxeye daisy, Leucanthemum vulgare Perennial pepperweed, Lepidium latifolium Plumeless thistle, Carduus acanthoides Poison hemlock – conium maculatum Russian knapweed, Rhaponticum repens Russian olive, Elaeagnus angustifolia Salt cedar, Tamarix chinensis, T. parviflora, and T. ramosissima Scentless chamomile, Tripleurospermum Scotch thistle, Onopordum acanthium Spotted knapweed, Centaurea stoebe ssp. micranthos Sulfur cinquefoil, Potentilla recta Yellow starthistle – centaurea solstitalis Yellow toadflax, Linaria vulgaris These plants are to be eradicated and or reported as required by Colorado Weed Management and Garfield County. Appendix A Date: 8/9/2024 to 8/9/2024 Address: Astera Parachute Pre Soak Start Time 10:15 Hole Depth 20" Add Gravel 2" Hole # 1 Test 1 Time Water Level inches Test 2 Time Water Level inches Test 3 Time Water Level inches Elapsed Min. Absorption Inches/10 Min. 2:17 16.50 2:51 16.50 3:50 16.5 0 0 2:27 10.25 3:01 12.25 4:01 12 10 6.25 2:37 6.50 3:11 9.00 20 3.75 2:47 3.75 3:21 6.00 30 2.75 3:31 4.50 40 4.25 3:41 2.75 50 3.25 60 3 70 1.5 80 1.75 30 12.75 50 13.75 11 4.5 80 26.5 TOTALS Min. & inch. Infiltration Rate 2.4 Min/In 3.6 Min/In 2.4 Min/In 3.0 Min/In 25.5 In/Hr 16.5 In/Hr 24.5 In/Hr 19.9 In/Hr Pre Soak Start Time 10:30 Hole Depth 16" Add Gravel 2" Hole # 3 Test 1 Time Water Level inches Test 2 Time Water Level inches Test 3 Time Water Level inches Elapsed Min. Absorption Inches/10 Min. 1:20 13.00 1:40 13.00 0 0 1:30 6.50 1:50 7.50 10 6.50 1:40 3.50 2:00 4.00 20 3.00 2:10 2.00 30 5.50 2:20 0 40 3.50 50 2.00 60 2.00 20 9.50 30 11.00 60 22.5 TOTALS Min. & inch. Infiltration Rate 2.1 Min/In 2.7 Min/In #DIV/0! Min/In 2.7 Min/In 28.5 In/Hr 22.0 In/Hr #DIV/0! In/Hr 22.5 In/Hr Precipitation Data: Parachute Site Colorado 2 year 6 hour 0.968 inches 0.16 inches per hour 5 year 6 hour 1.22 inches 0.20 inches per hour 10 year 6 hour 1.44 inches 0.24 inches per hour 100 year 24 hour 3.21 inches 0.13 inches per hour 0.18 Average (Using the max of the probability range) Combined Absorption RateStart Added Water Added Water Start Added Water Added Water Combined Absorption Rate Percolation Test Log 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 0 6.50 3.00 5.50 3.50 2.00 2.00 In c h e s o f d r o p Time Test Hole 3 Series3 test 2 conbined rate Appendix B APPENDIX C Rating Description Small commercial buildings are structures that are less than three stories high and do not have basements. The foundation is assumed to consist of spread footings of reinforced concrete built on undisturbed soil at a depth of 2 feet or at the depth of maximum frost penetration, whichever is deeper. The ratings are based on the soil properties that affect the capacity of the soil to support a load without movement and on the properties that affect excavation and construction costs. The properties that affect the load-supporting capacity include depth to a water table, ponding, flooding, subsidence, linear extensibility (shrink-swell potential), and compressibility (which is inferred from the Unified classification of the soil). The properties that affect the ease and amount of excavation include flooding, depth to a water table, ponding, slope, depth to bedrock or a cemented pan, hardness of bedrock or a cemented pan, and the amount and size of rock fragments. 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. Poor performance and high maintenance can be expected. 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). Solar Array, Ground-based Solar Arrays, Ballast Anchor Systems Ground-based solar arrays are sets of photovoltaic panels that are not situated on a building or pole. These installations consist of a racking system that holds the panel in the desired orientation and the foundation structures that hold the racking system to the ground. Two basic methods are used to hold the systems to the ground, based on site conditions and cost. One method employs driven piles, screw augers, or concrete piers that penetrate into the soil to provide a stable foundation. The ease of installation and general site suitability of soil- penetrating anchoring systems depends on soil characteristics such as rock fragment content, soil depth, soil strength, soil corrosivity, shrink-swell tendencies, and drainage. The other basic anchoring system utilizes precast ballasted footings or ballasted trays on the soil surface to make the arrays too heavy to move. The site considerations that impact both basic systems are slope, slope aspect, wind speed, land surface shape, flooding, and ponding. Other factors that will contribute to the function of a solar power array include daily hours of sunlight and shading from hills, trees, or buildings. Ballast anchor systems can be used in some places where soil-penetrating systems cannot, such as in shallow or stony soil. Also, since they do not penetrate the soil, ballast systems can be used where the soil is contaminated and disturbance is to be avoided. The soil in the area must have sufficient strength to be able to support the vehicles that haul the ballast and the machinery to install it. Soils can be a non-member, partial member or complete members of the set of soils that are limited for "Ground- based Solar Panel Arrays". If a soil's property within 150 cm (60 inches) of the soil surface has a membership indices greater than zero, then that soil property is limiting and the soil restrictive feature is identified. The overall interpretive rating assigned is the maximum membership indices of each soil interpretive property that comprise the "Ground-based Solar Panel Arrays" interpretive rule. Minor restrictive soil features are identified but not considered as part of the overall rating process. These restrictive features could be important factors where the major restrictive features are overcome through design application. Soils are placed into interpretive rating classes per their rating indices. These are not limited (rating index = 0), somewhat limited (rating index greater than 0 and less than 1.0), or very limited (rating index = 1.0). Numerical ratings indicate the degree of limitation. The ratings are shown in decimal fractions ranging from 0.01 to 1.00. They indicate gradations between the point at which a soil has the least similarity to a good site (1.0) and the point at which the soil feature is very much like known good sites (0). OWTS, 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. Poor performance and high maintenance can be expected. 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). Steel, "Risk of corrosion" pertains to potential soil-induced electrochemical or chemical action that corrodes or weakens uncoated steel. The rate of corrosion of uncoated steel is related to such factors as soil moisture, particle- size distribution, acidity, and electrical conductivity of the soil. Special site examination and design may be needed if the combination of factors results in a severe hazard of corrosion. The steel in installations that intersect soil boundaries or soil layers is more susceptible to corrosion than the steel in installations that are entirely within one kind of soil or within one soil layer. The risk of corrosion is expressed as "low," "moderate," or "high." Concrete, "Risk of corrosion" pertains to potential soil-induced electrochemical or chemical action that corrodes or weakens concrete. The rate of corrosion of concrete is based mainly on the sulfate and sodium content, texture, moisture content, and acidity of the soil. Special site examination and design may be needed if the combination of factors results in a severe hazard of corrosion. The concrete in installations that intersect soil boundaries or soil layers is more susceptible to corrosion than the concrete in installations that are entirely within one kind of soil or within one soil layer. The risk of corrosion is expressed as "low," "moderate," or "high."