Reclamation of urban areas

A literature study was conducted in order to compare the effectiveness and cost of different reclamation procedures that may be employed after an accident on a nuclear facility takes place in which radioactive material is released to the atmosphere. A substantial anount of work has been done on reclaming soil and snow-covered surfaces. Using scrapers or other soil-moving equipment decontamination factors are 10-100. (The decontamination factor is the ratio of the contamination before to that after the decontamination procedure). However, information on decontamination of paved areas by simple methods such as firehosing and vacuum sweeping are poorly documented. Therefore, only a very uncertain figure in the range 2-10 can be given for the decontamination factor here. It is recommended that a major effort be made in the future to investigate the efficiency of these simple methods, because of their relatively low cost. Also, more expensive methods for reducing the dose such as vacuuming, road planing and deep plowing are treated because of their feasibility under certain circumstances. Using these methods dose reduction factors in the 2-100 range can be obtained. Very expensive techniques, such as sandblasting, water cannon, flame spalling, etc. are justifiable usable only in special situations and are therefore considered very briefly here. The methods vary widely in cost. A simple method like vacuum sweeping costs $0,004 per square meter of surface; whereas one like road planing can reach $4 per square meter. A more sophisticated technique like flame spalling costs as much as $100 per square meter.