Common Questions and Answers
Common Questions and Answers
Type Curves
Q. I selected a type curve method from the menu. The pump test data appeared on the screen, but no type curves. What happened?
A. Type curves are stored in a windows metafile with a EMF extension. The file COOPER.EMF should have been placed in the directory containing the program executable at the time of installation. When a type curve method is selected, these files are called up to display the type curves. Check to make sure the EMF file is located in the correct directory. If you are running the program from a floppy drive, the type curves may not appear even though the files are available. This is because the program can not access them fast enough from a floppy drive. Check Help | About to determine which directory should contain COOPER.EMF.
Test Methods
Q. Output results from the automated methods have a lot of hydraulic conductivity values. Which one is correct?
A. This answer requires some professional judgment on the part of the user. In the final output file, calculations are summarized with arithmetic and geometric means of hydraulic conductivity. You will probably get less disagreement if you select the geometric mean as the actual answer. For the Bouwer and Rice method, the hydraulic conductivity determined by sensitivity analysis is probably the best estimate of true hydraulic conductivity.
It may be helpful to use a graphical method to exclude some data points from the analysis. Data excluded from the graphical analysis will also be excluded from the automated solutions. If the best fit line in the graphical analysis is a good fit to all of the points, there is less likely to be variation in the results of the automated solutions.
Q. I have heard about something in the Hvorslev method called a Shape Factor. How does Super Slug determine this value?
A. The Hvorslev method includes a value called a shape factor that is dependent on how much of the aquifer is penetrated by the well. For partial penetration, the shape factor depends on the ratio of horizontal hydraulic conductivity to vertical hydraulic conductivity. This value must be estimated before the test data is analyzed. For full penetration, the shape factor depends on the radius of influence of the test. Super Slug approximates the radius of influence with the well screen length, which is sufficient in most cases. If the ratio of horizontal hydraulic conductivity to vertical hydraulic conductivity is not entered, Super Slug calculates the shape factor as if there were full penetration. If the ratio is entered, Super Slug evaluates the amount of penetration, and either use the ratio for one of the partial penetration scenarios, or uses the full penetration Shape Factor.
Operation
Q. How come the bottom left corner buttons sometime disappear during the Hvorlsev graphical analysis?
A. If the method is weighting the analysis to the first point, and is not recalculated head ratio with each data adjustment, you will not be able to add or subtract data from the beginning of the analysis. Therefore, the arrows disappear.
Q. I always use the same units when I collect data for a slug test. Is there a way to set up Super Slug so that I don't have to keep selecting these units?
A. Super Slug will save settings such as unit selection and window size. Set the units you want, including output file format. Check Options | Save Settings on Exit and exit the program. To keep changed settings from being saved in the future, restart the program, un-check Options | Save Settings on Exit, and exit the program again.