RESTON, VA, June 12, 2007 -- The Environmental and Water Resources Institute of the American Society of Civil Engineers (EWRI/ASCE) today announced it will conduct a public comment period on a new, two part professional standard, Fitting of Hydraulic Conductivity Using Statistical Spatial Estimation (KSTAT). The final public comment period for the two KSTAT Standard documents will be held from June 15, 2007, to August 30, 2007.
KSTAT Standard One (Standard Guideline for Fitting Saturated Hydraulic Conductivity Using Probability Density Functions) includes: range of applicability; estimation of sample average, standard deviation and coefficient of skew; the role of a coefficient of skew in choosing a probability density function (pdf) to fit saturated hydraulic conductivity (K) data; fitting K data with lognormal pdf; and fitting K data with the (3-parameter) log-gamma pdf. The standard outlines a procedure to optimize the fitting and goodness-of-fit testing of a pdf to a sample of saturated K measurements.
KSTAT Standard Two (Standard Guideline for Calculating the Effective Saturated Hydraulic Conductivity) includes: purpose and quantitative interpretation of the effective saturated K; range of applicability; calculation of the sample average, geometric mean and standard deviation; calculation of the effective saturated K when it is lognormally distributed with very small variance or has arbitrary pdf and variance; and examples of the calculation of the effective saturated K in which K is log-gamma distributed or exponentially distributed with isotropic covariance. The standard outlines a procedure to calculate the effective saturated K in local-scale groundwater flow.
To participate in the public comment period, contact Phillip Mariscal, ASCE Standards Administrator, at [email protected] or (703) 295-6338. For more information on the standard, or ASCE's standards program, please contact An Pham at [email protected] or (703) 295-6408.
Created in 1999, the American Society of Civil Engineers' Environmental & Water Resources Institute (ASCE/EWRI) is one of seven full-service institutes created to serve the needs of members and allied professionals working within specialized fields of engineering.
Founded in 1852, the American Society of Civil Engineers represents more than 140,000 civil engineers worldwide and is America's oldest national engineering society.
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