Screenings and Preliminary Assessments

PRELIMINARY ASSESSMENT: SOURCE AREAS AND WASTE CHARACTERISTICS

This section covers past, present, known, and potential sources of hazardous substances at the site. These comprise areas with documented releases of hazardous substances, where there is a threat of release, or where hazardous substances have been stored or disposed of.

A source can mean any building, structure, installation, equipment, pipe or pipeline (including any pipe into a sewer or publicly owned treatment works), well, pit, pond, lagoon, impoundment, ditch, landfill, storage container, above-ground or underground storage tank, motor vehicle, or any area where a hazardous substance has been deposited, stored, disposed of, placed, or otherwise come to be located, and where a release has occurred or where there is a threat of a release.

This section includes areas where hazardous substances may be present but do not pose a threat of release to the environment. All areas where hazardous substances are handled should be listed.

Discussion of permitted or authorized releases belong in the PA’s Regulatory History section. A permitted or authorized release is a release from an active facility that is subject to and in substantial compliance with a current and legally enforceable permit issued by an authorized public agency [Oregon Administrative Rule 340-122-115]. Note that deposition, accumulation, or migration of substances resulting from an otherwise permitted or authorized release is excluded from the definition of a permitted or authorized release [OAR 340-122-073].

Where detailed information is not available, such deficiencies should be noted, and estimates used for source containment, size, and quantity/types of contaminants present. This section will also identify hazardous substances that have not been handled in the hazardous substance release areas listed above. Describe how the facility uses, treats, disposes of, or recycles these substances.

For each source, where a release or a threat of a release exists, describe:

1. Name and location of source
2. Type of source - landfill, surface impoundment, container, storage tank, contaminated soil, pile, etc. A landfill is an engineered hole in the ground into which hazardous substances have been disposed by backfilling or by contemporaneous soil deposition that covers wastes from view. A surface impoundment is a topographic depression, excavation, or diked area, formed from earthen materials (lined or unlined) and designed to hold wastes containing free liquids. Drums are portable containers that hold a standard 55-gallon volume of hazardous substances. Tanks and Non-Drum Containers are other portable or stationary devices used to contain accumulated wastes. A pile is any non-containerized, above-ground accumulation of solid, non-flowing wastes, including open dumps.
3. Current use and length of use - active, inactive, documented clean-closed, undocumented clean-closed, frequency and dates of use, etc.
4. Permits addressing source (if applicable).
5. Type and condition of containment - Is the source lined or unlined? Is it breached or unbreached, is there a cap or cover, and if so, what type? Are containment structures maintained, and if so, at what intervals does this maintenance occur?
6. Name and quantity of hazardous substances and contaminated media found in each source, including past and current disposals. If actual quantities are unknown, use estimates based on areal extent or volume (from dimensions of the release area). If available, provide documentation in the form of analytical results and manifests.
7. Documented releases of hazardous substances - A release is defined as any spilling, leaking, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, or disposing into the environment. Releases include the abandonment or discarding of barrels, containers, and other closed receptacles containing a hazardous substance. Releases exclude the following:
   • Releases that result in exposure to a person solely within a workplace with respect to a claim that the person may assert against the person's employer under ORS chapter 656 (i.e., OSHA).
   • Emissions from the engine exhaust of a motor vehicle, rolling stock, aircraft, vessel (watercraft), or pipeline pumping station engine.
   • Any release of source, by product or special nuclear material from a nuclear incident, as those terms are defined in the Atomic Energy Act of 1954, as amended, or any removal, remedial action, or release of source, by-product or special nuclear material from any processing site designated under section 102(a)(1) or 302(a) of the Uranium Mill Tailings Radiation Control Act of 1978.
   • The normal application of fertilizer.

   A release can be verified through visual or analytical evidence, facility documentation, or owner/operator admission.

8. Pathways affected or potentially affected - Is the source contributing to contaminant migration? A pathway is the route by which a hazardous substance can migrate to a target or receptor. Four pathways are used to evaluate a site: 1) groundwater; 2) surface water; 3) air; and 4) direct contact (soil).
9. Disposal history (both on- and off-site) for each waste type, including names of companies contracted with for disposal, and locations of disposal.
10. Accessibility to source by the public and on-site workers, including whether the source is fenced, the extent of fencing, and type of security present.

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