Buried material

A small fraction (less than 1%) of the fixed carbon produced by photosynthesis is buried and physically removed from any potential reaction with oxygen (until the buried material is brought to the surface - at a much later time). Thus, the oxygen in our contemporary atmosphere is the consequence of many millions of years of fixed carbon burial. More details on this topic can be found in Chapters 8 and 11. 

When salts in groundwater precipitate and crystallize within the cavities of buried materials such as pottery, cement, and wood, they may generate internal pressures sufficient to disrupt these materials and turn them into gravel. Salts are also active in blistering and scaling painted surfaces on a variety of materials. 

In places where there are concerns about buried materials or sources of contamination, ground penetrating radar (GPR) surveys may be helpful in determining the best sampling approach. GPR can also detect coarse textured subsoils and water relationships in soils having these types of horizons. However, there are some limits as to where GPR can be used and the equipment for doing a GPR survey is expensive [3],... 

Lawson, T Hopkins, D. W Chudek, J. A., Janaway, R. C and Bell, M.G. (2000). Experimental earthwork at Wareham, Dorset after 33 years 3 Interaction of soil organisms with buried materials. /. Archaeol. Sci. 27, 273-285. 

Location of buried materials at a hazardous waste site is usually for the purpose of remedial action l.e., excavating these materials and ultimately disposing of them. The key unknowns are type (bulk-dumped or packaged in drums or other containers), quantity (volume of waste number of drums), and location, particularly depth of burial. The concerns are for safe excavation without puncturing containers or breaching any existing trench liners and thus aggravating the cleanup problems. 

Excavation The exposure, recording, and recovery of buried materials from the past. 

Annex A of BS7430 gives formulae for various shapes of buried conductors. See also Appendix H of Reference 1. Reference 2 shows the mathematical derivations of some basic cases. Reference 3 provides much useful information regarding buried materials. If the rod or pipe is surrounded by a casing or backfill of more conductive material such as Bentonite, then a lower resistance is obtained for the same depth, the formula is -... 

One of the most difficult problems associated with buried CWM is the lack of available information. Even at well-documented burial sites, the condition of the material in the subsurface is usually unknown. Even when many sophisticated geophysical procedures are employed in attempting to determine the identity and condition of the buried material, until excavation and positive identification can be made, the actual hazards associated with the material remain relatively unknown. Archeological type excavation by hand is frequently employed in uncovering CWM,... 

The sample at Baker 3 revealed 2800 ppb of benzo(a)pyrene. This has probably been removed with the cleanup of a nearby disposal site. At Baker 5, the level was 170 ppm it is unclear whether this has been removed. POI 24 had multiple compounds detected in nearly every sample. Its proximity to the Lot 18 excavations suggests the likelihood of buried material. 

Choosing the correct burial site is important, since the environment will have a direct effect on the performance of buried materials. This choice must take into account more than just characteristics of a soil, and must include consideration of local conditions of temperature, rainfall, and location. For example, a soil located in a valley near a stream provides a different environment to the same soil on a nearby hill. In general, the best test site is near the structure... 

Due consideration must be given to the environment that surrounds the metal. For instance, water containing copper ions, like seawater, is likely to form galvanic cells on a steel surface of the tank. If the water in contact with steel is either acidic or contains salt, the galvanic reaction is accelerated because of the increased ionization of the electrolyte. In marine environments, galvanic corrosion may be accelerated due to increased conductivity of the electrolyte. In cold climates, galvanic corrosion of buried material is reduced because of the increased resistivity of soil. In warm climates, on the other hand, it is the reverse because of the decreased resistivity of the soil. 

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