Geophysical Survey of Xiangyin Landfill Site
Last update time : 03/01/2018
Purpose and mission
The test area is located in Xiangyin County, Hunan Province. The landfill site is next to the Xiangjiang River. The type of the site is an unlawful dumping landfill with no bottom protection measures. It is adjacent to the surrounding agricultural land and has the problem of exudation of garbage seepage. The types of landfill are mainly living Trash, the geophysical exploration range of about 25,000 square meters, the test area as shown in Figure 1-1 below.
The test area will also measure the ERT resistivity method and induction electromagnetic method method,evaluating the geophysical technology on a large area of waste landfill area and the applicability of the understanding of the underground buried distribution, including evaluation of buried depth, boundary, volume, leachate characteristics and surrounding land formation, providing reliable information for future construction.
Work planning and deployment
The detection project range is about 26000 square meters, and 13 ERT resistivity measurement lines are arranged in the garbage field.
Analysis of Induced Electromagnetic Method
|EM||26,000Square meter||20m||20,000point||20～30m||0.2～0.3m||Fast detection of the distribution range of high conductivity waste water exudation water|
|ERT||100||25m||4PVES、2PVES||30～40m||1～2m||Detection of landfill depth, burial volume, and groundwater pollution position|
As the detection results shown that the whole stratum electricity can be roughly divided into four layers from top to bottom, the resistivity show high resistivity (first layer) and low resistivity (second layer), high resistivity (third layers) and high resistivity (fourth layer) electrical change trend, that is the original formation with depth the electrical resistivity trends to rise.
The first layer of evaluation for dry garbage and soil, has the characteristic of high resistivity, a depth of about 0 to 2.5 meters, the range of resistivity is about 15 ~ 60 Ohm-m, the resistivity falls on the green to red and yellow color, analysis of average depth of about 0 to 2.5 meters.
Second layer composite evaluation for wet resistivity living garbage and landfill leachate, because it contains a lot of leachate, has obvious characteristics of low resistivity value, the resistivity value range is about 100 ~ 150 Ohm-m, the resistivity levels fall in blue interval,the average depth is about 2.5 ~ 12 meters.
Third layer composite evaluation for the living garbage and wet background formation at the junction of composite resistivity, has obvious characteristics of low resistivity, the resistivity analysis range is about 10 ~ 20 Ohm-m, the resistivity levels fall in green interval, analysis of average depth of about 8 to 18 meters.
3D ERT resistivity method Interpreted
The landfill ERT resistivity method to E-1 field E-13 line results establish the 3D model, it can obtain all the field data results. As shown, the overall analysis of 0 ~ 15 meters most are low resistivity, resistivity less than 20 Ohm-m, through the 3D depth section shows a depth of 15 meters, the formation resistivity have been rising feature analysis, has been close to the original formation, suggesting that 3D section depth of 18 ~ 20 meters for the original formation, no landfill resistivity. The distribution of 3D resistivity below 15~20 Ohm-m is analyzed. The average buried depth is 11.5 m to 13.5 M. the volume volume of garbage is about 300 thousand to 350 thousand M3.
Note: the analysis of the resistivity below 20 Ohm-m, the volume of garbage distribution is about 30~35 million cubic meters.