Storm conditions

As mentioned earlier, the process facilities have been designed to operate in environmental conditions based on a 1-year storm condition. During the 2 years that have elapsed, several bad weather periods have been experienced during which significant wave heights of 21 ft [6.S ml have been observed. It has been established that the worst environmental conditions encountered so far do cause liquid movement in the separators but have not adversely affected (he functioning of the process and utility systems and do not cause level alarms or shutdowns. 

Tropical Storm Watch Tropical storm conditions with sustained winds from 39 to 73 mph are possible in the watch area within the next 36 hours. 

Tropical Storm Warning Tropical storm conditions are expected in the warning area within the next 24 hours. 

Local flow systems dominate groundwater circulation at shallow depths (down to as much as 100 m) in humid regions (i.e., having significant diffuse areal recharge), unless the topography is very flat (Toth, 1963). Such systems vary from —100 m to several kilometers in horizontal scale. It is the discharge from such systems that supports surface-water flow in streams and rivers under all but storm conditions. The primary control on... 

They are greater in the winter months because of the broadening of the distributions of and v under storm conditions ( and v are E-W and N-S velocity components). In Long Island Sound the pellets at the sediment-water interface undergo frequent resuspension before their incorporation into the permanent sediment. Dispersion of resuspended pellets by both advection and diffusion is rapid. New silt-clay-size mineral matter Introduced into the Sound will be rapidly distributed throughout the layer of pellets mantling the mud buttom. Chemical species adsorbed on silt-clay particles will be similarly dispersed. 

CMA is not only costly but also slower in action than rock salt. When applied as a solid, CMA exhibits marginal performance in light traffic freezing rain and dry and cold storm conditions. However, when CMA is applied as a solid or concentrated solution, the rate of action is similar to that of rock salt. The New York City DOT has... 

Inclement weather conditions. Consideration will be given to weather related conditions. If the wind, rain, or storm conditions, or other situations regarding hazardous weather occur, this operation will be temporarily suspended. ... 

Consider emergency access and egress from the site in storm conditions. 

Figure 2. Storm conditions at the end of dismantling of existing pier...

An announcement that tropical storm conditions exist with sustained winds of 39-73 mph and conld hit a specified coastal area within the next 48 h. 

A facility that is down for even 5 min can suffer a significant loss of productivity or data that may take hours or days to rebuild. A blackout affecting a transportation or medical center could be hfe threatening. Coupled with this threat is the possibihty of extended power-service loss due to severe storm conditions. Many broadcast and communications relay sites are located in remote, rural areas, or on mountaintops. Neither of these kinds of locations are weU known for their power reliability. It is not uncommon in mountainous areas for utihty company service to be out for days after a major storm. Few operators are willing to take such risks with their businesses. Most choose to install standby power systems at appropriate points in the equipment chain. 

Wave and swell observations for both normal and storm conditions ... 

Second, seiches affect the design and management of a movable storm surge barrier (MSSB) in Rotterdam Waterway (Fig. 8.1), which protects the low areas behind it against flooding. The MSSB must be closed dm-ing extreme storm conditions. In that case a semi-closed basin is created on its seaside. Seiches are expected to occur in this temporary basin, with a dominant eigenperiod of approximately 30 min. These contribute to the failure probability of the barrier, but their expected heights were not known. 

Often it is not possible to build a perfect filter separating the mound breakwater from the bed, particularly under water. Some movement of sand in the mound pores under heavy waves can therefore be anticipated in these cases. Moreover, if the bed is composed of fine sand some liquefaction or partial liquefaction of the upper layers are possible in storm conditions. 

For those processes that are mainly driven by the wave action under storm conditions, the proposed methodology assumes that each storm is an independent realization or run of the same underlying stochastic process. In such a way that each year is considered as a random sequence of runs and pauses. 

---