Risk Management Plan Data Elements

2. Toxics: Worst Case

Complete once for each Program 1 process containing a regulated toxic, and once to represent all regulated toxic substances held above the threshold quantity in Program 2 and Program 3 processes. In addition, you may need to complete additional worst-case release scenario(s) for a hazard class if a worst case release from another process within the source potentially affects public receptors different from those potentially affected by the worst-case release reported. See the RMP Offsite Consequence Analysis (OCA) Guidance for more information on determining your worst-case release scenarios.

2.1 Chemical name: The name of the regulated chemical evaluated in the worst-case scenario.

2.2 Physical state: Indicate with a check mark the physical state of the chemical as it is released in the scenario.

1. Gas: Indicate with a check if the chemical is a gas.

2. Liquid: Indicate with a check if the chemical is a liquid.

2.3 Results based on: Indicate with a check mark whether you used the reference tables provided in the RMP OCA guidance or conducted modelling to calculate your worst-case release. If you performed modelling, you must also indicate which model was used.

2.4 Scenario: Indicate with a check mark which of the following release scenarios describes your worst-case release scenario.

1. Explosion: A rapid chemical reaction with the production of noise, heat, and violent expansion of gasses.

2. Fire: A product (e.g., fuel) in a state of combustion.

3. Toxic gas release: A release of the substance in a vapor state.

4. Liquid spill and vaporization: A release of the substance in a liquid state with subsequent vaporization.

2.5 Quantity released: Indicate the quantity of the chemical released during the worst-case release in pounds.

2.6 Release rate: Indicate the rate of release in pounds per minute.

2.7 Release duration (if modeled): Indicate the length of time in minutes for the vessel, pipeline, or other location of the regulated substance to release all of its contents. For gasses, the duration is 10 minutes.

2.8 Wind speed: This is 1.5 meters per second unless you can demonstrate that local meteorological data applicable to the source show a higher minimum wind speed at all times during the last three years. If you can demonstrate higher minimums existed at all times, these minimums may be used. Provide wind speed in meters per second.

2.9 Stability class: This is an "F" stability class unless you can demonstrate that local meteorological data applicable to the source show a less stable atmosphere at all times. If you can demonstrate less stable conditions existed at all times, these minimums may be used.

2.10 Topography (check one): Indicate with a check mark whether the local topography is urban or rural. Urban means that there are many obstacles in the immediate area; obstacles include buildings or trees. Rural means that there are few buildings or other obstacles in the immediate area.

2.11 Distance to endpoint: Indicate the distance to the endpoint in miles for the chemical, using the endpoint specified for the chemical in Appendix A of the risk management program rule.

2.12 Residential population within distance: Indicate the population within the distance to the endpoint as specified in question 11 of this section. Populations should be estimated within a circle with a center at the point of the release and a radius determined by the distance to the endpoint. Populations estimated need only include residential populations and may be rounded to two significant digits (e.g., 5,500, 11,000).

2.13 Public receptors: These are the public receptors within the distance to the endpoint specified in the worst-case release. Public receptor means locations offsite where members of the public may be exposed to toxic concentrations, radiant heat, or overpressure as a result of an accidental release. Residences, institutions, industrial, office, and commercial buildings, parks, or recreational areas inhabited or occupied by the public at any time without restriction by the source are public receptors. You do not need to list specific locations or estimate populations at these locations. The presence of these receptors may be determined by using local street maps. Check all that apply.

1. Schools: Public and private elementary, secondary, or higher education schools.

2. Residences

3. Hospitals

4. Prisons

5. Public recreational areas or arenas: These include stadiums, parks, and public pools.

6. Major commercial, office or industrial areas: Industrial parks, office buildings, shopping malls, commercial areas.

2.14 Environmental receptors within distance: Environmental receptors should be identified within a circle with a center at the point of the release and a radius determined by the distance to the endpoint. Environmental receptor means natural areas, such as national or state parks, forests, or monuments; officially designated wildlife sanctuaries, preserves, refuges, or areas; and federal wilderness areas that could be exposed at any time to toxic concentrations, radiant hear, or overpressure as a result of an accidental release and that can be identified on local U.S. Geological Survey maps. Check all that apply.

1. National or state parks, forests, or monuments

2. Officially designated wildlife sanctuaries, preserves, or refuges

3. Federal wilderness areas

2.15 Passive mitigation considered: Mitigation means specific activities, technologies, or equipment designed or deployed to capture or control substances upon loss of containment to minimize exposure of the public or the environment. Passive mitigation means equipment, devices, or technologies that function without human, mechanical, or other energy input. Check all that were considered in defining the release quantity or rate to the worst-case scenario.

1. Dikes: A low wall that acts as a barrier to prevent a spill from spreading.

2. Enclosures: Physical containment of the release within a structure (e.g., a building).

3. Berms: A mound or wall of earth at the top or bottom of a slope that prevents a spill from spreading.

4. Drains: A channel that carries off surface water.

5. Sumps: A pit or tank that catches liquid runoff for drainage or disposal.

6. Other (specify)

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