Soils movement

The wind fences/screens method uses screens, which take up or deflect a sufficient amount of wind so that the wind velocity is lowered below the threshold required for initiation of soil movement. The maximum reduction of wind velocity is expected for a distance of one to five fence heights downstream. Tests have shown that wind screens can achieve up to 60% efficiency in controlling inhalable particulates and 75% of total suspended particulates at wind speeds of about 10 to 13 mi/h. 

Flexible conforms to subsurface soil movement and will not crack under stress. 

Applicability in fine-grained soils around buried structures (tanks, pipes, etc.) may be limited because of soil movement. 

Although the majority of an applied triazine herbicide remains in the surface soil where it controls weeds while degrading, soil movement and persistence has been well studied and documented. A variety of factors affect triazine runoff, including method of application, soil properties, type of tillage, and environmental conditions. Estimates of triazine amounts in runoff from agricultural fields vary widely, with the highest concentrations occurring in the first 2 months after application. 

Measurements will be made of the form and levels of elements in soil, movement of elements to plant roots, uptake of elements by plant roots, and translocation to above-ground, and edible portions of plants. The elements to be studied include magnesium, calcium, potassium, zinc, phosphorous, nitrogen, iron, manganese, copper, and aluminum. 

Hoang TQ, Dai LC, Hong Thom LT. 1989. Effects of geographical conditions, soil movement and other variables on the distribution of 2,3,7,8-TCDD levels in adipose tissues from Vietnam Preliminary observations. Chemosphere 18 967-974. 

Geoiogy. An example of electrochemistry in geology concerns certain types of soil movements. The movement of earth under stress depends on its viscosity as a siurry that is, a viscous mixture of suspended solids in water with a consistency of very thick cream. Such mixtures of material exhibit thixotropy, which depends on the interactions of the double layers between colloidal particles. These in turn depend on the concentration of ions, which affects the field across the double layer and causes the colloidal structures upon which the soil s consistency depends to repel each other and remain stable. Thus, in certain conditions the addition of ionic solutions to soils may cause a radical increase in their tendency to flow. 

Keep Soils Out of Sewers Use road sweeper to remove dirt from roadways and concrete areas which would otherwise blow or be washed into the drainage system. Develop and install new sewer boxes designed to reduce soil movement into sewer system, particularly from Tankfarm area. Estimate cost for installation on a refinery-wide basis. Both items reduce soil infiltration, in turn reducing hazardous solid waste generation. 

Chemically resistant masonry joints in clay pipe are rigid. Ground movement, such as settlement, can therefore break the pipe. For this reason it is important that all industrial waste lines be laid with continuous support. No matter what opinion others may have of the stability of the soil in the area where the pipe is to be laid, this writer has never seen any trench excavation, no matter how well prepared, that did not require adjustment to attain the suitable smooth surface and slope after the trenching operation had been completed. These adjustments require fill in some spots and further surface removal in others. In addition bell excavations are required to provide working room to make the joints. After the line is in service, heavy rains, flooding and even percolation of groundwater can cause soil movement above and around the pipe, and eventually, without uniform support, movement will take place that breaks the pipe. 

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