TIME LAG AND SOIL PERMEABILITY IN GROUND-WATER OBSERVATIONS

A REVIEW IS PRESENTED OF IRREGULARITIES IN GROUND-WATER CONDITIONS AND THE PRINCIPAL SOURCES OF AIR IN GROUND-WATER OBSERVATIONS. MANY OF THESE SOURCES OF ERROR CAN BE ELIMINATED BY PROPER DESIGN, INSTALLATION, AND OPERATION OF OBSERVATION WELLS, PIEZOMETERS, OR HYDROSTATIC CELLS. SINCE PORE-WATER PRESSURES CHANGE CONTINUALLY DURING THE PERIOD OF OBSERVATIONS, THEY MUST BE CORRECTED FOR INFLUENCE OF THE TIME LAG. THEORETICAL AND EXPERIMENTAL METHODS FOR DETERMINATION OF THE TIME LAG AND ITS INFLUENCE ON THE RESULTS OF GROUND-WATER OBSERVATIONS ARE PROPOSED. SIMPLIFICATIONS ARE OBTAINED BY INTRODUCING A TERM CALLED THE BASIC TIME LAG, AND SOLUTIONS ARE PRESENTED FOR STATIC, UNIFORMLY CHANGING, AND FLUCTUATING GROUND-WATER CONDITIONS. DATA ARE PRESENTED WHICH WILL ASSIST IN THE PRACTICAL APPLICATION OF THE PROPOSED METHODS. FORMULAS FOR DETERMINATION OF THE FLOW OF WATER THROUGH VARIOUS TYPES OF INTAKES OR WELL POINTS ARE SUMMARIZED AND EXPANDED TO INCLUDE CONDITIONS WHEN THE COEFFICIENTS OF THE VERTICAL AND HORIZONTAL PERMEABILITY OF THE SOIL ARE DIFFERENT. DETERMINATION OF THE COEFFICIENTS OF VERTICAL AND HORIZONTAL PERMEABILITY FOR THE SOIL IN SITU BY MEANS OF TIME LAG OBSERVATIONS IS THEORETICALLY POSSIBLE AND IS DISCUSSED BRIEFLY.

  • Supplemental Notes:
    • Bull No 36, 50 PP, 18 FIG, 34 REF
  • Corporate Authors:

    U.S. Army Waterways Experiment Station

    3909 Halls Ferry Road
    Vicksburg, MS  United States  39180-6199
  • Authors:
    • Hvorslev, M J
  • Publication Date: 1951-4

Subject/Index Terms

Filing Info

  • Accession Number: 00234450
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 28 1994 12:00AM