Loading...
HomeMy WebLinkAbout1.05 Impact analysisImpact Analysis Encana Oil and Gas (USA) Inc South Middle Fork Water Facility OLSSON ASSOCIATES OA Project No. 012-0400 826 21 '/2 Road 1 Grand Junction, CO 81505 1 TEL 970.263.7800 1 FAX 970.263.7456 Encana Oil & Gas (USA), Inc. South Middle Fork Water Facility Impact Analysis Article IV, 4-502 E.1. Adjacent Property Garfield County Assessor's GIS data was used to create adjacent parcels map identifying parcels located within 200' of the subject parcel boundary. Below are the tax parcel numbers in bold and the corresponding land owners and mailing addresses. Surface Owners Parcel Number: 217112300003 Mobil Oil Corp PO Box 53 Houston, TX 77001 Parcel Number: 217133100020 Encana Oil & Gas (USA) Inc. KE Andrews & Company 1900 Dalrock Rd Rowlett, TX 75088 Parcel Number: 217133200019 Sandy Hotard, Mgr Land Dept WPX Energy Rocky Mountain, LLC PO Box 370 Parachute, CO 81635 Parcel Number: 217134200017 Puckett Land Company 5460 S Quebec St, Ste 250 Greenwood Village, CO 80111 Parcel Number: 217134300022 Sandy Hotard, Mgr Land Dept WPX Energy Rocky Mountain, LLC PO Box 370 Parachute, CO 81635 Impact Analysis Page 1 Mineral Owners Encana Oil & Gas (USA) Inc. c/o K E Andrews & Company 3615 S Huron Street, Suite 200 Englewood, CO 80110 Bureau of Land Management c/o: Colorado River Valley Field Office 2300 River Frontage Road Silt, CO 81652 Article IV, 4-502 E.2. Adjacent Uses The adjacent uses within a 1500' radius of the site primarily consist of agricultural activities and natural gas extraction. There is a private residence located approximately 1/4 mile from the project site on the east side of County Road 215. The proposed use is consistent with existing uses in the surrounding area. These uses will not be adversely impacted by construction and operation of the water impoundment facility on the subject property. Article IV, 4-502 E.3. Site Features The site is located on private lands approximately three miles north of the Parachute, Colorado city limits in the SW1/4NW1/4 of Section 34, and the NE1/4 of Section 33, Township 6 South, Range 96 West, 6th Principal Meridian. There is an existing access to this site that is located north of the Wheeler Gulch Road intersection. This access will be eliminated when the new access is constructed and the Water Facility is completed. Terrain is relatively flat at an elevation of approximately 5,577 feet above sea level on the valley floor of the eastern edge of the Piceance Basin. The specific location for the proposed facility is not within any identified slope hazard areas. Slope hazard areas do exist surrounding the proposed site. As noted in the Geotechnical Report prepared by Yeh and Associates, the site slopes down to the west and southwest at grades of less than 2 percent. No significant faults or fissures have been identified proximate to the proposed location. The Geotechnical Report noted that "the site appeared suitable for the proposed construction." The site is located within a historically irrigated agricultural area that has begun to revert to a xeric plant community. The affected vegetation on the project site consists of rabbitbrush and greasewood with an understory of mixed of native and non-native grasses and forbs. Native vegetation in undisturbed areas surrounding the site is composed of greasewood and sagebrush shrublands, pinyon -juniper woodlands, and a riparian area along Parachute Creek. Impact Analysis Page 2 No significant natural features are located in close proximity to the project area. As a result of applying engineering design criteria detailed in the accompanying diagrams, implementation of storm water best management practices (BMPs) and EnCana's industry BMPs the water impoundment facility will not affect the surrounding vegetation and water resources. No major geological hazards exist in the immediate vicinity of the proposed facility. The proposed facility is not located within a floodplain or floodway. Article IV, 4-502 E.4. Soil Characteristics According to information prepared by the Natural Resources Conservation Commission Soil Survey soils in these sections have been mapped as Arvada loam (3), Halaquepts (27), and the Olney loam, (50). Arvada loam (3), soils are developed on 1 percent to 6 percent slopes, and consist of well drained soils on terraces, and fans. Elevations range from 5,100 feet to 6,200 feet above mean sea level. The parent material of this soil is highly saline alluvium derived from sandstone and shale. The Halaquepts (27) is developed on 0 percent to 6 percent slopes, at elevations of 5,400 to 7,400 feet. Found in landform setting of terraces, fans, and valleys. The parent material of this soil is alluvium. The Olney loam (50) soils are developed on 3 to 6 percent slopes, and consist of well drained soils on valley sides, and alluvial fans at elevations of 5,000 to 6,500 feet. These soils are alluvium derived from sandstone and shale. A copy of the Custom Soil Resource Report is included under the supplemental material tab. Article IV, 4-502 E.S. Geology and Hazard A Geotechnical Investigation for the proposed facility has been prepared by Yeh and Associates, Inc. and included in the Supplemental Materials Section. As described in the report, the project area is located at the confluence of Parachute Creek Road (County Road 215), Wheeler Gulch and Riley Gulch approximately 4 miles northwest of Parachute, Colorado. Parachute Creek is located west of the site. This area is located in the Piceance Basin of western Colorado, a complex of numerous anticlines and synclines and a major gas production area. The asymmetrical, arc -shaped basin is 100 miles long by 50 miles wide and is oriented northwest -southeast and is deepest on the east edge. It is bounded structurally on the northeast by the Axial Uplift, on the east by the White River Uplift/Grand Hogback and the Elk Mountains, on the south by the Uncompahgre Uplift and on the west by the Douglas Creek Arch. Exposed in the project area is Tertiary age sedimentary rocks including the ledge forming red, gray, and brown sandstone and siltstone and the slope forming variegated (purple, gray and brown) claystone of the Wasatch Formation. The surficial deposits include alluvium and flood plain deposits of mud, silt, sand and gravel and coalescing alluvial fans and sheetwash deposits of locally derived materials. Other deposits observed at the site included artificial fill in the stockpiles. No geologic hazards have been mapped by Garfield County in this area and no faults or other hazards are evident on the Geologic Map of Colorado. No other hazards have been observed by Encana. Impact Analysis Page 3 Article IV, 4-502 E.6. Effects on Existing Water Supply and Adequacy of Supply The effects from construction and operation of this facility on existing supplies of freshwater on the region will be negligible. The proposed project will primarily store water produced from Encana's natural gas wells in the area; therefore, no supply of water is required and little or no demand will be placed on local water resources related to the collection and storage of produced water. Water delivered to the facility will not infringe on any existing water rights. The produced water generated from Encana's natural gas production operations and stored at this facility is a result of Encana's drilling operations within the Williams Fork Formation. Williams Fork Formation is classified as a non -tributary formation. Details specific to the non -tributary nature of the water that will be delivered to the proposed facility are provided in an attachment accompanying this submittal. In the future Encana may store Colorado River water in these ponds. Documentation regarding the nontributary status of the water used, as well as water rights showing Encana's right to draw water from the Colorado River, are included with this application. Water will be delivered to and removed from the new ponds at South Middle Fork via trucks and the pipeline connecting the South Middle Fork Water Treatment Facility and the South Middle Fork Ponds. A source of non -potable water will be supplied for the restroom facility at the control room. Potable water will be provided via a licensed provider with adequate water rights. Article IV, 4-502 E.7. Effects on Groundwater and Aquifer Recharge Areas According to the Geotechnical Report, groundwater was encountered during drilling. The report determines that groundwater will not impact the off-load pad area, however, based on proposed pond bottom elevations, groundwater could impact the ponds. Due to capillary action and current groundwater levels, pond liners may be susceptible to floating/uplift. Encana will implement the recommendations contained in the Geotechnical Report, including but not limited to additional groundwater measurements, especially in the springtime, during high seasonal groundwater and possibly before construction. Dewatering and/or subgrade stabilization may be necessary for the construction of the ponds in order to provide a stable platform. Variations in groundwater conditions may occur seasonally. The magnitude of the variation will be largely dependent upon the amount of spring snowmelt, duration and intensity of precipitation, site grading changes, and the surface and subsurface drainage characteristics of the surrounding area. Taking into consideration the information and recommendations contained in the Geotechnical Report, the facility has been designed to eliminate the potential of produced water impacting surface or ground waters. The facility will be designed according to engineering standards required by the COGCC as part of the E&P waste permitting process. Stormwater management and other drainage controls have been designed into the facility as shown on the Grading and Drainage diagram as well as on the Construction Erosion Control Plan(s). Additional details related to surface and ground water protection are included in sections 3.0, 4.0 and 5.0 of Encana's Storm Water Management Plan (SWMP) The produced water impoundments will be double lined with 60miI liner(s), a leak detection system and high level detection Impact Analysis Page 4 monitors/alarms will be installed for each pond. Additionally, groundwater monitoring wells will be utilized if required by the COGCC as part of their E&P Waste Facility Review. A complete assessment of the potential impacts to shallow groundwater and aquifers is required as part of the Colorado Oil and Gas Conservation Commission (COGCC) Form 28 review and approval process. No migration of hydrocarbons is anticipated to the existing groundwater. In order to ensure protection of water quality, Encana will install ground water monitoring wells in proximity to the facility. These wells will be installed, regularly monitored and reclaimed according to the criteria identified by the COGCC and adherence to Rule 908 of the COGCC code. Article IV, 4-502 E.B. Environmental Effects As detailed in the Wildlife and Vegetative Impact Analysis Report accompanying this submittal, given the limited construction activity and small footprint of the proposed facility, there will be minimal impacts to natural habitat as a result of construction and operation of the facility. To mitigate impacts associated with the proposed project Encana will adhere to the recommendations included in the Wildlife and Vegetative Impact Analysis Report. No impacts to federally listed or locally significant plant or animals are anticipated. See the Wildlife and Vegetative Impact Analysis Report for further information. Article IV, 4-502 E.8.a Determination of the Long Term and Short Term Effect on Flora and Fauna. FAUNA Raptors One potential Cooper's Hawk nest site occurs within 0.25 miles of the site, although nest occupancy could not be ascertained at the time of the survey. Potential Burrowing Owl habitat exists in the prairie dog colony, although inspection of the burrows revealed no sign of owls. No potential nest trees would be removed. Foraging habitat for raptors would be lost within the project footprint. The potential Cooper's Hawk nest is within 260 feet of a busy access road that provides access to Starkey Gulch and is approximately 815 feet from the proposed water treatment facility. Due to the scale and continuity of human activity in the area, indirect impacts related to human presence, vehicle traffic, and equipment operation are not expected. American Elk and Mule Deer The additional human activity associated with construction of the project may affect mule deer and elk in the surrounding area by creating avoidance areas if construction takes place during the winter and early spring months. The site was previously cleared of native vegetation, but some plants that have re-established on the site are being utilized by big game. Approximately 26.3 acres of foraging habitat would be removed within the project footprint. Due to sparse vegetation that is dominated by plants with low forage value for big game, the project would result in a small additional loss of habitat value. Due to the scale and continuity of other human activities nearby, the indirect disturbance from operation of the water treatment facility is Impact Analysis Page 5 probably low, as big game animals have become at least partially accustomed to human presence. Black Bear and Mountain Lion No vegetation will be lost in habitats that are important for black bear or mountain lion. Indirect effects from construction disturbance should not affect either species. Black bear encounters with construction personnel could occur if garbage or food is available on the site. If bears learn to associate human activity with creation of a food source, the resulting encounters sometimes result in the euthanasia of offending bears by the CPW. Small Mammals, Birds (including BCC), Reptiles, and Amphibians Approximately 0.49 acres of an occupied prairie dog colony would be removed by the proposed access road to the facility, and mortality from vehicles can be expected. Effects of habitat loss to other species are expected to be low due to poor habitat conditions resulting from previous development of the project area and the large amount of habitat available in the surrounding area. No aquatic habitats would be directly impacted by the project. FLORA The vegetation removed as a result of this project is primarily aggressive native species and weedy annual species that have become established on previously disturbed soils. Vegetation surrounding the project area will not be affected and will likely remain in its current condition. Article IV, 4-502 E.8.b Determination of the effect on significant archeological, cultural, paleontological, historic resources. Based on the results of the Class 1 inventory, Flattops Archaeological Consultants recommends a finding of no historic properties affected. Therefore, construction and operation of the proposed facility will not impact any cultural or historic resources. Article IV, 4-502 E.8.c Determination of the effect on designated environmental resources, including critical wildlife habitat. The development of the project is not expected to significantly affect any critical wildlife habitat for any wildlife species. Potential issues are outlined below. Creation of hazardous attractions: Wildlife may perceive the water treatment facility as watering source and should be prevented from accessing the pits. These pits could create a drowning or entrapment hazard for birds and wildlife if sufficient barriers (fencing, netting) or deterrents are not included as part of the project, along with escape mechanisms including ramps and proper sloping. Some passerine bird species may choose to nest in or on equipment or objects at the water treatment facility. By closing or covering all ports, hatches, cavities, and openings (such as the ends of pipes) this potential is decreased. Most non -game bird species are protected under the Impact Analysis Page 6 Migratory Bird Treaty Act (16 U.S.C. 703-712; Ch. 128; July 13, 1918; 40 Stat. 755) and tampering with occupied nests could be considered a "take" resulting in a violation. Alteration of Existing Vegetation: Vegetation within the project footprint is dominated by aggressive native and weedy non-native species due to prior soil disturbances. The 26.3 acre area affected by the project would be cleared of vegetation. No rare or special status species of plants would be affected. Big Game: The project would be located adjacent to a designated wildlife corridor recognized by Encana to allow minimally restricted movement from the Wheeler Gulch area to Parachute Creek. Fencing could pose a hazard to animals if not built to wildlife friendly standards as outlined by CPW guidelines (Hanophy 2009). Roadkill: Although vehicle speeds on the proposed access road are likely to be low, the road would pass through a white-tailed prairie dog colony and some degree of roadkill would be expected. Bird Nesting Habitat: The vegetation that would be removed is of poor quality for nesting by most bird species; nesting habitat for ground nesting species would be lost. Indirect Construction Effects: Operation of the facility introduces increased human presence and noise, which have the potential to affect wildlife distribution and habitat use in a negative manner. Since the site exists amid significant human presence related to other activities in the area, the additional disturbance from this project is low but does contribute to cumulative effects. Article IV, 4-502 E.8.d Evaluation of any potential radiation hazard that may have been identified by the State or County Health Departments. There are no potential radiation hazards associated with this facility. Article IV, 4-502 E.8.e Spill Prevention Control and Counter Measures plan, if applicable The facility will be covered under Encana's Spill Prevention Control and Countermeasures (SPCC). All hydrocarbon based liquid storage will be in accordance with the SPCC plan. Containment will be designed to accommodate 110% of the largest storage volume, including but not limited to earthen berms, impervious liners and steel containment. Article IV, 4-502 E. 9. Traffic Construction at the water storage facility will result in a temporary traffic increase as follows: Impact Analysis Page 7 Phase Vehicles Duration Construction Phase 10-15 pickups and 2 semi trucks* Cranes Earth moving equipment 6 months Lining Phase 4-6 pickups 3 weeks Cover Phase 4-6 pickups 4-6 weeks *Semi trucks will be utilized on first and last days of construction phase No additional mobilization of heavy equipment will be required for this location. All vehicles hauling equipment and material for project construction on County Road 215 will abide by Garfield County Road and Bridge's oversize/overweight regulations. All construction and operations personnel will park on the proposed site and will not block or hinder normal traffic on County Road 215. All activities on this site will be conducted out of the right-of-way of County Road 215 on the subject parcel, and all loading and unloading of vehicles will be conducted out of the public right-of-way. As discussed in the previous section, the construction of this facility will result in minor, temporary increases in traffic on County Road 215. As noted previously, this facility will ultimately result in a significant reduction in tanker truck traffic required to haul water to Encana's operations. Regardless of the traffic volume, Encana will implement the following measures, as necessary, to minimize impacts to transportation and roads: Control dust along unsurfaced access roads and minimize tracking of soil onto paved roads, as required by the CDPHE Construction Stormwater Permit and as per the details contained in the Dust Control Plan. Comply with county and state weight restrictions and limitations. Limit construction and operation traffic speeds to a low and reasonable level. Keep dusty, exposed areas damp with water or a magnesium -chloride solution or other dust suppressant. Stabilize traffic areas with gravel. Revegetate or stabilize non -traffic areas as soon as practicable. As detailed in the Auxiliary Lane Analysis, prepared by River City Consultants, access is proposed via a new access to County Road 215. This access will be the fourth leg of the County Road 215/Wheeler Gulch Road intersection. The Auxiliary Turn Lane Assessment addressed the sight distance, trip generation, directional distribution, site -assignment of trips, and recommendations for auxiliary turn lanes associated with the proposed Encana Oil & Gas South Middle Fork Water Facility near Parachute, Colorado. Based on the CDOT Access Code, the projected trip generation and directional distribution, a northbound left -turn deceleration lane is not warranted based on the revised use and trip generation but will be provided due to truck traffic. A copy of this report is included in the supplemental materials section. Impact Analysis Page 8 There is an existing access to this site that is located north of the Wheeler Gulch Road intersection. This access will be eliminated when the new access is constructed and the Water Facility is completed. Article IV, 4-502 E.10. Nuisance Adjacent lands will not be impacted by the generation of vapor, dust, smoke, noise, glare or vibration. Encana will apply the appropriate level of controls to accommodate potential impacts via adherence to CDPHE Air Quality regulations and the implementation of industry BMPs included in the SWMP and Encana's dust control plan. This proposed use will comply with Colorado Revised State Statute regarding noise impacts at all times. Article IV, 4-502 E.11. Reclamation Plan Encana estimates that the proposed facility will be in operation for an anticipated period of approximately thirty (30) years during development and production of Encana's Garfield County operations. Upon termination of the development and production activities, the facility will be reclaimed, as outlined below: All equipment and structures will be removed. Encana will remove all safety and storm water BMPs, and other surface objects from the premises. Encana will restore the site to pre -facility conditions by re -contouring and re -vegetating the site. Top soil will be redistributed across the site and will be reseeded with an approved seed mix (see attached seed mix recommendation). Encana will monitor the site to ensure that 70 percent of the pre-existing vegetation is achieved. Seedbed Preparation and Slope Reconstruction: Cut and fill slopes will be backfilled and re-contoured to a slope of 3:1 — 2.5:1 or less in instances where necessary to match the existing natural contours. Following final contouring, all backfilled or ripped surfaces will be covered evenly with topsoil. Re -contouring should form a complex slope with heavy pocking. In areas with slope greater than 3 percent, imprinting of the seed bed is recommended. Final seedbed prep will consist of scarifying/imprinting the topsoil prior to seeding. Imprinting can be in the form of dozer tracks or furrows perpendicular to the direction of slope. When hydro -seeding or mulching, imprinting should be done prior to seeding, unless the mulch is to be crimped into the soil surface. If broadcast seeding and harrowing, imprinting will be done as part of the harrowing. Furrowing can be done by several methods, the most simple of which is to drill seed perpendicular to the direction of slope in a prepared bed. Other simple imprinting methods include deep hand raking and harrowing, always perpendicular to the direction of slope. All compacted areas will be ripped to depth of 18" with max furrow Impact Analysis Page 9 spacing of 2'. Where practicable, ripping will be conducted in two passes at perpendicular direction. Topsoil: Following final contouring, all backfilled or ripped surfaces will be covered evenly with topsoil. The topsoil in the cut slope on the back of the pad will be heavily pocked using the excavator bucket to form an uneven soil surface complex which will aid in revegetation and help with slope stabilization. The fill slope, and remaining disturbed, and reclaimed areas will be track walked to aid in revegetation and slope stabilization. In areas that may not have been disturbed during the reclamation process or areas of suspected compaction that will be reseeded, measures will be taken to loosen and spread the topsoil. These measures may include scarifying the soil by racking or harrowing the soil. Seeding Procedures: For best results and success, the recommended grass mixture reseeding should be done in late autumn in order to take advantage of natural precipitation for the region. The reseeding rate should be doubled for broadcast application. Preferred seeding method is multiple seed bin rangeland drill with no soil preparation other than simple grading to slope and imprinting and waterbars, where applicable. Alternative seeding methods include, but are not limited to: harrow with just enough soil moisture to create a rough surface, broadcast seed and reharrow, preferably at a 90 degree angle to the first harrow; hydro -seeding (most economical in terms of seed cost); and hand raking and broadcast followed by re -raking at a 90 degree angle to the first raking. These are not the only means of replanting the site. However, these methods have been observed to be effective in similar landscapes. The prepared soils will be seeded (weather permitting) no more than 24 hours following completion of final seedbed preparation. The seeding will be conducted by means of drilling the prescribed seed at prescribed seeding rate. The seed will be drilled with a common range drill at a depth of 0.25 — 0.5" beneath the soil surface. The seed will be drilled horizontally across the pad faces and perpendicular to the track walking when possible. When slope gradient less than 2.5:1 exists and drilling is not possible from a mechanical and safety standpoint the soils will be broadcast seeded at twice the prescribed amount. The reseeding will be monitored and reseeded as appropriate until the reclamation standards detailed above are met. Mulch: With 24 hours of reseeding (weather permitting) hydromulch will be applied to all reclaimed and reseeded surfaces. Areas where the erosion potential is such that biodegradable blankets will be used will not be hydromulched. Impact Analysis Page 10