Volume 2: Draft Gorst Planned Action Environmental Impact Statement

GORST PLANNED ACTION EIS | AFFECTED ENVIRONMENT, SIGNIFICANT IMPACTS, AND MITIGATION MEASURES• Since encountering unreported spills or unreported underground fuel tanks is a risk when performingconstruction, require contractors to provide hazardous materials awareness training to all grading andexcavation crews on how to identify any suspected contaminated soil or groundwater, and how to alertsupervisors in the event of suspected contaminated material. Signs of potential contaminated soil includestained soil, odors, oily sheen, or the presence of debris.• Require contractors to implement a contingency plan to identify, segregate, and dispose of hazardous waste infull accordance with the MTCA.• Require contractors to develop and implement the Stormwater Pollution Prevention Plan, BMPs, and otherpermit conditions to minimize the potential for a release of hazardous materials to soil, groundwater, orsurface water during construction.• Require contractors to follow careful construction practices to protect against hazardous materials spills fromroutine equipment operation during construction; prepare and maintain a current spill prevention, control,and countermeasure plan, and have an individual on site designated as an emergency coordinator; andunderstand and use proper hazardous materials storage and handling procedures and emergency procedures,including proper spill notification and response requirements.• Require contractors to identify all ACM and lead-based paint in structures prior to demolition activities inaccordance with 24 CFR Part 35. If ACM or lead-based paint is identified, appropriately trained and licensedpersonnel would contain, remove, and properly dispose of the ACM and/or lead based paint materialaccording to federal and state regulations prior to demolition of the affected area.• If warranted, require contractors to conduct additional studies to locate undocumented USTs and fuel linesbefore construction of specific development projects (areas of concern include current and former commercialand residential structures) and will permanently decommission and properly remove USTs from project sitesbefore commencing general construction activities.The following general mitigation measure would minimize or eliminate operational impacts within the Study Areaand could be incorporated into the Planned Action Ordinance.• Require applicants for development on properties identified as having potential for contamination to conducta thorough site assessment. If contamination is discovered then require the applicant to comply with all stateand federal regulations for contaminated sites.Significant Unavoidable Adverse ImpactsUnder all of the alternatives future redevelopment of contaminated sites would presumably occur, potentiallyresulting in the release of hazardous materials to soil, groundwater, and surface water, or exposure of workers andthe public to these materials. Most of these potential impacts would occur within the UGA, at industrial sites.Contaminants from existing sites within the study area could continue to be transported off of these sites as aresult of stormwater and flooding issues. Such movement of contaminants would continue to impact surfacewater, groundwater, and soil resources within the study area. These impacts would be greatest under Alternative1, and lower under Alternatives 2 and 3, which would address stormwater and flooding issues in the UGA as well aslimit future land clearing in areas of protection in the watershed. Contaminated sites would be avoided duringproject design when possible. Implementing the mitigation approaches described above would reduce adverseeffects on human health and the environment.Draft | June 2013 3-97