Wind Energy Decommissioning/Site Reclamation Impacts
Decommissioning and site reclamation activities that may cause environmental impacts include turbine, pad, and facility removal, land recontouring, and revegetation.
Typical activities during the wind energy facility decommissioning and site reclamation phase include turbine and facility removal, breaking up of concrete pads and foundations, recontouring the surface, and revegetation. Potential impacts from these activities are presented below, by the type of affected resource.
Air Quality (including Global Climate Change and Carbon Footprint)
Emissions from decommissioning activities include vehicle tailpipe emissions; diesel emissions from large construction equipment and generators; and fugitive dust from many sources such as land clearing, structure removal, backfilling, dumping, restoration of disturbed areas (e.g., grading, seeding, planting), and truck and equipment traffic. Permitting would be required (as during construction), and therefore these emissions would not likely exceed air quality standards or impact climate change.
Sources of noise during decommissioning would be similar to those during construction, and would result primarily from equipment (e.g., rollers, bulldozers, and diesel engines) and vehicular traffic. Whether the noise levels exceed EPA guidelines or local ordinances would depend on the distance to the nearest residence. If near a residential area, noise levels from blasting and some equipment operation could exceed the Environmental Protection Agency (EPA) guideline, but would be intermittent and occur for a limited time.
Decommissioning activities would be unlikely to impact cultural resources because these resources would have been removed professionally prior to construction, or would have been already disturbed or destroyed by prior activities. Collection of artifacts could be a problem if access roads were left in place and the area was not monitored.
Visual impacts of the wind development would be mitigated if the site were restored to its preconstruction state. However, despite the physical removal of the development, the impact of a scarred landscape on an area considered sacred to Native Americans would likely remain.
Impacts to biological resources from decommissioning activities would be similar in nature to impacts from construction, but of a reduced magnitude. There would be temporary increases in noise and visual disturbance associated with the removal of wind energy project facilities and site reclamation. Negligible to no reduction in wildlife habitat would be expected, and injury and mortality rates of vegetation and wildlife would be much lower than they would be during construction. Removal of turbines and meteorological towers would eliminate impacts associated with wildlife interactions with wind facility structures and habitat fragmentation. Following site reclamation, the biological resources at the project site could return to preproject conditions.
If significant impacts occurred in any resource areas, and these impacts disproportionately affected minority or low-income populations, then there could be environmental justice concerns. Issues that could be of concern during decommissioning are noise, dust, and visual impacts from the project site.
Hazardous Materials and Waste Management
Substantial amounts of solid and industrial waste would be generated during the decommissioning and dismantling of the facility. Much of the solid material could be recycled and sold as scrap or used in road building or bank restabilization projects; the remaining nonhazardous waste would be sent to permitted disposal facilities.
Industrial wastes (lubricating oils, hydraulic fluids, battery electrolytes, dielectric fluids, coolants, solvents, purging solutions, and cleaning agents) would be treated similarly to maintenance wastes during operation (put in containers, characterized and labeled, possibly stored briefly, and transported by a licensed hauler to an appropriate permitted off-site disposal facility). Impacts could result if these wastes were not properly handled and were released to the environment.
Human Health and Safety
Potential impacts to worker and public health and safety during the decommissioning of a wind energy development would be similar to those from any construction-type project with earthmoving, crushing, large equipment, and transportation of overweight and oversized materials. In addition, health and safety issues include working at heights, working in potential weather extremes, and possible contact with natural hazards, such as uneven terrain and dangerous plants, animals, or insects.
Upon decommissioning, land use impacts resulting from construction and operation of a wind facility would be largely reversed. No permanent land use impacts would occur during this phase.
Decommissioning activities have little potential to impact paleontological resources because these resources would have been removed professionally prior to construction, or would have been already disturbed or destroyed by prior activities. Fossil collection could be a problem if access roads were left in place and the area was no longer periodically monitored.
Direct impacts would include the creation of new jobs for workers during decommissioning activities, and the associated income and taxes paid. Indirect impacts would occur from new economic development and would include things such as new jobs at businesses that support the decommissioning workforce or that provide project materials, and associated income and taxes. Decommissioning activities would not be expected to affect property values.
Soils and Geologic Resources (including Seismicity/Geo Hazards)
Activities during the decommissioning phase that would impact soils and geologic resources include removal of access and on-site roads, substations, buildings, and other structures; and heavy vehicle traffic. Surface disturbance, heavy equipment traffic, and changes to surface runoff patterns can cause soil erosion. Impacts of soil erosion include soil nutrient loss and reduced water quality in nearby surface water bodies. Upon completion of decommissioning, disturbed areas would be recontoured and revegetated to minimize the potential for soil erosion.
Short-term increases in the use of local roadways would occur during the decommissioning period. Heavy equipment would remain at the site. Overweight and oversized loads could cause temporary disruptions to local traffic.
During decommissioning, visual resource impacts would be similar to those from construction. Impacts could occur from road redevelopment, temporary fencing of the work site, removal of buried structures and equipment, intermittent or phased activity persisting over extended periods of time, and the presence of idle or dismantled equipment, if allowed to remain on site.
Restoring a decommissioned site to preproject conditions would entail recontouring, grading, scarifying, seeding and planting, and perhaps stabilizing disturbed surfaces. Newly disturbed soils would create visual contrasts that would persist at least several seasons before revegetation would begin to disguise past activity. Restoration to preproject conditions may take much longer. Invasive species may colonize newly and recently reclaimed areas. Nonnative plants that are not locally adapted could produce contrasts of color, form, texture, and line.
Water Resources (Surface Water and Groundwater)
Water might be trucked in from off-site or obtained from local groundwater wells or nearby surface water bodies, depending on availability. It would be used for dust control for road traffic, dismantling of towers, substations, and other buildings; and for consumptive use by the decommissioning/site reclamation crew.
Water quality could be affected by activities that cause soil erosion, weathering of newly exposed soils leading to leaching and oxidation that could release chemicals into the water, discharges of waste or sanitary water, and pesticide applications. Upon completion of decommissioning, disturbed areas would be contoured and revegetated to minimize the potential for soil erosion and water-quality-related impacts.
Surface and groundwater flow systems would be affected by withdrawals made for water use, wastewater and stormwater discharges, and the diversion of surface water flow for access road reclamation or stormwater control systems. The interaction between surface water and groundwater could also be affected if the two resources are hydrologically connected, potentially resulting in unwanted dewatering or recharging of any of these water resources.