Soil-sampling data

Figure 2. Plot of the first two factors (accounting for 69 percent of the variance) from a principal components analysis of the residential soil sample data (n = 38) from El Coyote using 11 chemical elements (Al, Ba, Ca, Fe, K, Mg Mn, Na, P, Sr, Ti). Ovens tend to have higher concentrations ofBa, Fe, and Na (which are all highly correlated, r>.7) compared to hearths, while hearths tend to have higher concentrations of P, K, Al, Mg and Ti (which are all highly correlated, r>0.7) compared to ovens.

Review soil sampling data and compare levels against dioxin comparison values (environmental media evaluation guide or EMEG for children) that are not site-specific. If one or more soil sampling values exceed the screening value of 50 parts pertrillion (ppt) of toxicity equivalents (TEQs), further site-specific evaluations are needed as described next and in Tablet. 

Since the average concentrations for the 5 ASL of the Naples province have been calculated exclusively on soil sample data whereas stream sediments samples have been used for the rest of the ASL, geochemical data from different media were not mixed in statistical analysis. 

A baseline risk assessment is conducted to assess the potential human health and environmental impacts associated with soil contamination. The primary exposure pathways evaluated for explosives contaminated surface soils are dust inhalation, soil ingestion, and dermal absorption. Reasonable Maximum Exposure (RME) concentrations are based on the 95% upper confidence interval (UCI) on the arithmetic mean of soil sampling data. The land use scenarios quantitatively evaluated may include industrial and residential use, utilizing EPA standard default exposure parameters. 

The District of Columbia was also concerned that the Remedial Investigation is dated June 1,1995, whereas the Record of Decision recommending no further action was first presented to the public on March 23,1995. This creates the appearance of a rush to judgment. The risk assessments did not include the FRA soil sample data. Moreover, there was no mention of the FPA s extremely high arsenic readings. Because the FPA and the Army analyzed different samples, not including the FPA data in the risk assessment for all chemicals was fundamentally flawed. 

Calculate... void ratio, degree of saturation, water content, density, and unit weight from a given set of soil sample data. (3)... 

Outdoor soil Pb Nationally measurement approach representative residential soil Pb val ues Soil sampling data Predictive model near facility to estimate soil regression modeling Pb, using a farther away surrogate location ... 

If the designer is to do the job properly, it is important to have accurate data on which to base calculations. That is why test borings and proper laboratory analysis to determine the E value of the soil sample are essential. An arbitrary textbook selection of a soil modulus should always be avoided. However, if a pipe is to be buried deeper than the sampling zone that underwent laboratory testing to determine E and if the test bore shows the deeper material to be equal or better, then the designer may increase the E value proportionally to the square root of the differential soil stress. 

Ihnat M (1993) Reference materials for data quality. In Carter MR, ed. Soil Sampling and Methods of Analysis, Chap. 26, pp 247-262. Lewis Publishers, Boca Raton, FL. 

How critically interdependent matrix and analytical methods can be is illustrated in the example of the analysis of a soil sample. Table 7.1 shows the method dependent certified values for some common trace elements. The soil had been subjected to a multi-national, multi-laboratory comparison on a number of occasions (Houba et al. 1995) which provided extensive data. The data was subjected to a rigorous statistical program, developed for the USEPA by Kadafar (1982). This process allowed the calculation of certified values for a wide range of inorganic analytes. Uniquely, for the soil there are certified values for four very different sample preparation methods, as follows ... 

The soil residue level is determined from the relative responses of the analytes to the internal standards. A five-point calibration curve is analyzed in triplicate, and the data are analyzed by a weighted 1 /x linear regression model. The calculated slope and intercept from the linear regression are used to calculate the residue levels in the soil samples. A 20% aliquot of the sample extract receives 10 ng of each internal standard... 

Soil properties A Soil texture (sand, silt, clay), organic matter/carbon content, and pH Stones, roots, and hardpans must be largely absent to allow representative sampling of soil profile Soil properties should appear uniform over test site Soil texture data should be available at time of site selection. Soil properties must match study purpose. This can be realistic use conditions, realistic worst-case or worst-case in terms of agrochemical mobility and persistence Must ensure that the majority of samples can be taken from the deepest sampling horizon. Information about sub-soils can be obtained from soil maps, test coring and on-site interviews... 

Once soil samples have been analyzed and it is certain that the corresponding results reflect the proper depths and time intervals, the selection of a method to calculate dissipation times may begin. Many equations and approaches have been used to help describe dissipation kinetics of organic compounds in soil. Selection of the equation or model is important, but it is equally important to be sure that the selected model is appropriate for the dataset that is being described. To determine if the selected model properly described the data, it is necessary to examine the statistical assumptions for valid regression analysis. 

Soil Sample fusion with KF and pyrosulfate, coprecipitate with BaS04 Scintillation counter No data No data Sill and Williams 1969... 

Soil Sample leached with HNO3/HF, filtered, purified by KL-HDEHP resin columns, solvent extracted, and electrodeposition a -Spectroscopy No data 95-99% Guogang et al. 1998... 

Soil Drying of soil sample followed by sieving, digestion with HN03, filtration AAS no data no data Mielkeetal. 1983... 

Ground water t,/2 0.3 yr from observed persistence in groundwater of Netherlands (Zoeteman et al. 1981) t,/2 = 168-672 h, based on unacclimated grab sample data of aerobic soil from groundwater aquifers (Wilson et al. 1983 Swindoll et al. 1987 Howard et al. 1991). 

Fig. 2. Shiko Lake bedrock geology and soil sample locations. Geochemical data described here were compiled from BC Geological Survey studies by Lett Doyle (2009) and a Novagold Resources till survey (Petsel 2006).

A spatial join of the analytical data with BGS DiGMapGB-50 Superficial Geology returned data for 4,700 soil samples, which had been collected over glacigenic till deposits (Fig.1) of Mid-Pleistocene, Anglian age. 

Data have been compiled from 15 exploration campaigns between 1982 and 1988 (MR reports 628, 629, 630, 631,632, 641, 647, 649, 654, 657, 665, 669, 682, 2270, 2532), and one in 2007 (MR report 4307). These included stream sediment, pan concentrate, rock chip and soil sample media (Table 1). 

Fig 3. Factor 1 and 2 scores for (post-AAC) HXL-extraction data from the sub-soil samples. 

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