Laserfiche WebLink
<br />Characteristics <br /> <br />Collapsing and 5attl ing soils have considerable strength when <br />dry and genera II yare not a prob I em to structures and <br />improvements. When they become wet, they are subject to <br />rapid collapse and can be reduced In volume as much as 10 to <br />15 percent. Surface ground dIsplacement of several feet can <br />result. Similar processes frequently affect old landfills or <br />poor I y P I aced earth f II 15. <br /> <br />Consequences <br /> <br />The I arge ground d Isp I acements caused by co I I apsl ng 50 115 can <br />tota II y destroy roads and structures and a I ter surface <br />drainage. Minor cracking and distress may result as the <br />improvements respond to small adjustments In the ground <br />beneath them. <br /> <br /> <br />Hydrocompactlon of salls caused by a ruptured water line in <br />Boulder County. <br /> <br />42 <br /> <br />Aggravating Circumstances <br /> <br />:-.1ants activities are definitely the cause of most sol Is <br />collapsing. These activities Include watering grass and <br />shrubs, fai 1 iog to repair leaking water lines In utility <br />trenches, Impounding water, blocking drainages by highways, <br />loading excessive weight upon collapsible sol Is, and any <br />activIty which increases subsurface moisture in soi Is prone <br />to co I I ap se. <br /> <br />Man-made and/or man-placed materials frequently are subject <br />to collapse and settlement. The fi Illng of mined out areas, <br />natural depressions and swamps with trash and debris is a <br />common practice. Eventually the site Is put to another use. <br />Decomposition and compaction at landfill dumps also ~an <br />result in generation of explosive methane and poisonous <br />hydrogen sulfide gases, as well as pollution of subsurface <br />water with carbo I ic acid or other chemicals. These problems, <br />In addition to settl lng, occur despite compaction during the <br />landfi II operation. <br /> <br />Damage to structures erected on landfl lIs Is common if proper <br />construction methods are not used to counteract settl ing and <br />other prob I ems. Dangerous methane can seep into basements and <br />crawl spaces and explode, demol ishlng the structure. <br /> <br /> <br />These 50115 In Garfield County collapsed from wetting. <br />