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C I Product Integrity Process Chevron has developed and implemented a proactive product integrity process as we attempt to ensure that all of the products we refine and market always meet or exceed specifications. A significant part of the process attempts to ensure that customers receive clean and dry fuel. To this end we have adopted the following "best practices" in our tank design and maintenance standards. Tank covers Finished fuel tanks are covered with either steel roofs or geodesic domes to minimize the intrusion of rainwater and other contaminants such as dirt and rust. How Chevron Prevents Tank Fires Chevron goes beyond the basic industry practices outlined in the National Fire Protection Code (NFPA 30) for storage of flammable and combustible liquids. Serious tank fires generally develop in two different ways: the floating roof, which covers the liquid surface, loses buoyancy and sinks or partially sinks, or the tank overflows. To preserve the integrity of the floating roof, Chevron uses all steel construction with buoyant pontoons made of liquid tight steel compartments. Even if three compartments are punctured, the floating roof will remain buoyant, so a full surface fire cannot develop. If a fire does occur in a floating roof with inherent buoyancy, it is normally limited to a small rim fire in the annular space between the floating roof and the tank shell. Rim fires are easily extinguished with foam supplied by hand lines. Tank Alarm Levels Internal coating Tank bottoms and two feet up the first course are coated to minimize corrosion and extend tank life. Water sensors Sensors are being installed to detect water bottoms which can lead to tank corrosion and biological growth in the fuel/water interface. This supplements our vigorous tank water draw procedures. Sloping tank bottoms Bottoms are sloped to a sump, enabling water (or any other potential contaminants that settle out) to be collected and removed more effectively than conventional tank bottom designs. Our stringent overfill prevention program uses both the practices of API 2350 "Overfill Protection for Storage Tanks in Petroleum Facilities" and a redundant and independent, automated safety shutdown system to reduce tank fires produced by overfills. The automated shutdown system closes a block valve when the product level is too high and shuts off or diverts the receipt. Chevron believes that an efficient way to reduce the frequency and consequences of tank fires is the program outlined above. This preventive approach combined with our emergency response procedures and the manual method of fire fighting we employ provide a reliable, balanced alternative to tank fire protection. Overfill Prevention Standard What Actions Occur OD (Overfill or Damage point). Tank inlet valve closes automatically. Local external audible and visual alarms. LSH (Level Shutdown High)This is considered an "incident". Rising flow. 5 minute L$H On two-stage systems there is an additional Less than five minutes or six inches minimum response time. alarm (LAHH) above the LAH alarm. below OD. (See note 1 below) t See note 1 below LAH Local external audible and visual alarms. LAH (Level Alarm High) Working Capacity of Tank. Terminal automation graphics and LAL (Level Alarm Low) Normal maximum fill alarms. six inches above LSLL. level. Do not hit LAH No new truck loading allowed to begin. LSL (Level Shutdown Low) LAL ITS visual alarm. six inches above roof landing or loss of suction. Truck loading stopped. Tank discharge valve closes automatically. ITS visual alarm. Tank bottom Note 1: Any alarm system must have adequate response time to enable the operator to shutthe flow or directthe flow to a safe tank. Typically the minimum response time is 5 minutes. Note 2: Every pipeline system is checked for hydraulic shock to ensure pipeline is not over pressurized as a result of the automated shutdown system. M