18E.60.050 Increased Occupancy for Covered Assembly.
The occupancy limits for covered assembly structures within the Case II Lahar Inundation Zone, Travel Time Zone A, may be increased by the Director to a maximum of 400 persons when the following criteria have been met:
A. The applicant has demonstrated through submittal of a travel time analysis the amount of time that is anticipated for a lahar to reach the proposed project and evacuation route.
B. The applicant has demonstrated through submittal of a volcanic hazard emergency evacuation plan that:
1. The proposed project is located directly adjacent to a safety zone (area completely located outside the limits of a Case I lahar) that is within walking distance in an amount of time less than the anticipated time that it takes a lahar to reach a given point (refer to PCC 18E.60.020 C.). (Note: The time that it takes a lahar to reach a given point is calculated from either the source of the event to the given point, or from the source of the lahar warning signal to the given point, i.e., only the Puyallup and Carbon River drainages at this time have the Acoustic Flow Monitoring System. Other drainages, such as the Nisqually and White Rivers, have no warning systems. Persons in those areas would be reliant on other emergency notification systems, such as the National Weather Radio. At this time, no other warning system is planned for the Nisqually or White River drainages.) The time of walking distance shall be calculated based upon the amount of time necessary for physically or mentally challenged individuals to get from the proposed project to the safety zone.
2. The estimated travel time analysis for the lahar to reach the evacuation route is less than the estimated travel time for physically or mentally challenged individuals to have cleared the evacuation route and reached the safety zone.
3. The evacuation route must be at a slope and surface to be considered handicapped accessible (e.g., slopes may not exceed 1' in 12' rise and surface must be an all weather, hard material) as determined by the County Building Official.
4. The evacuation route has been determined not to contain any other potential natural hazards, such as landslide or flood hazards, to cause a blockage or destruction of the evacuation route during an event (i.e., seismic event triggers a landslide that results in the evacuation route becoming impassible).
5. The evacuation route is not located adjacent to any highways or arterial road networks that may cause a life safety threat to evacuating pedestrians.
6. The safety zone is an area with adequate ingress/egress (i.e., a direct exit once individuals reach this location).