1815 13TH ST SEPA 016 - 013 - PRMC NEW CLINIC BUILDING Land Use Decision Documents 2025-04-21

EVALUATION FOR AGENCY USE ONLY uncertainty would require additional research, subsurface exploration, sampling and/or testing. 3. Petroleum -impacted soil remains in a localized area on the adjacent PEMC property west of the site. The impacted soil originated from a release(s) of heating oil in residential USTs formerly at this location. Available reports do not indicate clearly whether impacted soil or groundwater on the adjacent western property extended to the subject Site. Based on the proximity of soil with diesel concentrations greater than the MTCA Method A cleanup level, this is considered a REC. 4. There is no documentation available regarding the original source of heating/cooling for the field house structure and prior structures on the site (original gymnasium and boys' club). Heating oil may have been used in the past for these structures. Further evaluation of this uncertainty would require additional research, subsurface exploration, sampling and/or testing. One additional environmental condition was identified in our Phase I ESA. Adjacent residences have or may have had heating oil AST or USTs. We were unable to verify the heating sources for adjacent residential properties. Releases of heating oil from adjacent properties could potentially impact the subject Site if the releases were of significant volume; however, the practical risk of this possibility given the relative distances between the subject Site and the adjacent residential properties appears reasonably low. All contamination that was found during initial development of the site for the Central Utility Plant and parking lot was cleaned up during that phase of the project. 2) Describe existing hazardous chemicals/conditions that might affect project development and design. This includes underground hazardous liquid and gas transmission pipelines located within the project area and in the vicinity. In addition to what has been noted above in the Phase 1 Environmental assessment, there are active fuel lines from active UST's immediately north of the Central Utility Plant which service the emergency generators and boilers located in the central utility plant. 3) Describe any toxic or hazardous chemicals that might be stored, used, or produced during the project's development or construction, or at any time during the operating life of the project. Chemicals used for form release agents and the curing and sealing of concrete, as well as fuels for powering equipment and oils for maintaining equipment, might be used during construction. These chemicals will be stored in a hazardous materials containment area secured against unintended uses. Environmental Checklist — Providence Regional Medical Center Everett — North Site Page 16 © 1!t2a Y