Seepage

CeUulosic fibers, powdered limestone, gHsonite, and asphalt are frequently added to both water and oH muds at levels of 10 to 25 kg/m (4—10 lb /bbl) when high differential pressures are encountered to control seepage losses to the formation. This treatment also is used to improve the quaHty of the mud filter cake to reduce the chance of differential pressure sticking. 

Tracer methods involving chemical markers injected into the contents of the tank may be used. Instmmentation capable of picking up the chemical marker can then determine the presence of a leak caused by seepage of the tracer into the ground. This, like the hydrocarbon sensing method, is genericaUy referred to as soil vapor monitoring. This method suffers the same weaknesses that have to do with undertank soil permeabUities. 

Taste and Odor Control. Tastes and odors in surface waters result from the action of biological organisms, eg, algae, or from various minerals, pollution by industry, domestic seepage, or agriculture. Groundwaters may have taste and odor if they are polluted or if they contain gases, eg,... 

Collective protection enclosures are required for groups of personnel. Such enclosures must be airtight to prevent inward seepage of contamination. They can be independent units or can be formed by adequately treating the interior walls of stmctures, tents, airplanes, or vehicles. A supply of uncontaminated air, provided by passing ambient air through high efficiency aerosol and carbon filters, must be provided. 

The market for PPVC film and sheet is only slightly less than for wire and cable insulation. Uses are as diverse as seepage barriers, factory doors, inflatables, baby pants, car trim, covering materials for book bindings and document cases and shower curtains. UPVC film has also been widely used for packaging of food, particularly for shrink-wrap purposes, but this market has been subject to some substitution by polypropylene. 

Stores should be ventilated and sound, e.g. no cracks in floors, no rusty window frames, no water seepages, etc. 

Soil surveys relating to eonstruetion work require samples from at least the depth of exeavation water seepage may eause eross-eontamination of land. Some guidelines for the elassifieation of eontaminated soils are summarized in Table 16.17. 

Petroleum Locate and eliminate seepage. Activated carbon will adsorb oil and gasoline (most hydrocarbons) on a short term basis. Airstrip with (40 1 air/water ratio) followed by 2 ft carbon units in series... 

The minus sign results from the definition of Ap, which is equal to p2 - Pi, a negative quantity. The term q is known as the seepage velocity and is equivalent to the velocity of approach v , which is also used in the definition of the Reynolds number. 

Absorption Field A system of properly sized and constructed narrow trenches partially filled with a bed of washed gravel or crushed stone into which perforated or open joint pipe is placed. The discharge from the septic tank is distributed through these pipes into trenches and surrounding soil. While seepage pits normally require less land area to install, they should be used only where absorption fields are not suitable and well-water supplies are not endangered. 

Distribution box Serves to distribute the flow from the septic tank evenly to the absorption field or seepage pits. It is important that each trench or pit receive an equal amount of flow. This prevents overloading of one part of the system. Dissolved solids Chemical substances either organic or inorganic that are dissolved in a waste stream and constitute the residue when a sample is evaporated to dryness. 

Infiltration The seepage of groundwater into a sewer system, including service connections. Seepage frequently occurs through defective or cracked pipes, pipe joints, connections or manhole walls. 

For services where ambient or inlet temperamres may fall below 0°C, flashback protection is provided by a special seal drum or loop seal in the inlet line. This equipment is designed specifically for the particular liquid and vapor materials being flared. In these cases a 150 mm minimum water layer is included in the bottom of the pit to prevent oil seepage into the ground, and the hydrocarbon inlet distributor is mounted 150 mm above the water surface. Details of the inlet distributor are shown in Figure 5. 

Versicherungsschein, m. insurance policy bond, vcrsickem, v.i. ooze away, seep away, percolate. Verslckening, /. seepage, percolation, versiegeln, v.t. seal, seal up. versiegen, v.i. dry up, be exhausted, versllbcm, v.t. silver, silver-plate. 

A very rapid seepage loss Gradual seepage loss... 

In order to prevent seepage loss of circulation to the vugular formation, bridging the formation—by properly sized, acid-soluble on oil-soluble resin particles as well as colloidal particles—should be considered. 

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