This form has been prepared to help the observer in collecting data on new subsidence occurrences. These reports, in conjunction with information from other sources, will provide a comprehensive data source on subsidence events.

1. DATE and time subsidence was first observed: 
    Month ______________ Day ____ Year _______
    Time___________am/pm.

2. LOCATION:  
    LONGITUDE: ______Degrees ______Min ______Sec.
    LATITUDE: _______Degrees ______Min ______Sec.
    County: ______________________ T____ R ____Section _____,
     _____1/4 of _____1/4. 7-1/2 min. Quad. Name_________________
     Name and Address of property where subsidence occurred:
     ____________________________________________________
     Phone: (     )__________

3. SUBSIDENCE DATA: (Circle or fill-in the blank).
    SIZE and SHAPE: Are dimensions measured ____or estimated ____?

    Is the shape roughly circular ____ or elongate____?

    Subsidence depression DIMENSIONS at surface: LENGTH______ feet; 
    WIDTH______ feet. DEPTH of subsidence below land surface:____feet

    Approximate SLOPE of depression walls when first observed: ______. 
    (Flat land slopes 0; a vertical wall slopes 90).

    Is there WATER in the depression? ____ Y ____ N. 
    DEPTH of water below land surface: _______ feet.

    Is LIMESTONE visible in the walls of the depression? Y____ N____. 

    Is a CAVERN or cavity visible in the depression? Y____ N____.

4. CIRCUMSTANCES OF COLLAPSE: How long did it take for the
    subsidence to form?________________________________________

    Were there any probable TRIGGERING MECHANISMS, such as: new
    construction nearby ___; new well-drilling nearby ___; blasting
    nearby___; heavy loading of the ground ___; heavy rainfall ___; heavy
    ground-water pumpage___; other_________________.

    Were there any PRE-COLLAPSE INDICATORS, such as: ponding of 
    runoff ___; ground cracks___; tilting of posts or trees ___; small
    preliminary holes ___; turbidity in nearby well ___; changes in nearby
    vegetation (wilting) ___; other___.

    Was there any property damage? ____ Y ____N Describe in
    COMMENTS, below.

    Was depression filled or repaired? ____ Y ____ N.  
    Is this planned? ____ Y ____ N.

5. TERRAIN CHARACTERISTICS:
    TOPOGRAPHY: flat, hilltop, slope, valley bottom, depression.
    Please describe any drainage channels or structures that are in the
    immediate area: _________________________________________

    LAND USE / COVER: cropland, pasture (or similar), forest, grove,
    wetland, suburban (low density), urban (high density), industrial
    SOIL TYPE at the site (eg.: white clean sand, orange clayey sand,
    etc.): _________________________________________________

    Is this depression in line with, or very near, other recent subsidence depressions? ____ Y ____ N

    Is this depression in line with, or very near, older subsidence depressions or lakes? 
    ____ Y ____ N. Please explain:
    _____________________________________________________

   ADD ANY OTHER COMMENTS OR OBSERVATIONS HERE:

    _____________________________________________________
    _____________________________________________________
    _____________________________________________________
    _____________________________________________________
    _____________________________________________________

    PLEASE SKETCH THE SUBSIDENCE DEPRESSION ON THE BACK OF THIS FORM.