Database Manual

Oak Ridges Moraine Groundwater Program

Appendix G.23

G.23 Population of D_INTERVAL_MONITOR (Top and Bottom)

D_INTERVAL_MONITOR contains various screen information - of primary importance (here) are the depths/elevations of the interval/screen top and bottom. Note that there should only be a single INT_ID row - no duplicate INT_IDs should be present.

A variety of screen ‘types’ are specified (as found in R_INT_TYPE_CODE; each screen type is given a ‘Screen’ tag in the INT_TYPE_ALT_CODE field; refer also to V_SYS_INT_TYPE_CODE_SCREEN). They are:

Each of these are described below. Note that some of these types are only used when there is a lack of information and various assumptions must be made. In the case where there is no depths (of any kind) reported, no screen is assigned.

Reported Screen (18)

The top- and bottom-depth of the screen has been reported as part of the dataset. This is used directly.

Assumed Screen (Overburden Well 1ft Screen Assigned) (19)

Reported Open Hole (20)

Assumed Open Hole (Bottom of Casing to Bottom of Hole) (21)

Casing information has been specified as part of the borehole construction information and bedrock has been intersected - no screen has been listed. In this case, the screen interval is taken as the bottom of the casing to the bottom of the hole.

Assumed Open Hole (Top of Bedrock to Bottom of Hole) (22)

If this is a bedrock well (i.e. the borehole intersects bedrock), the screen interval is taken from the top of bedrock to the bottom of the hole.

**Reported Open Hole (Derived from Borehole Construction) (27)*

Screen Information Omitted (28)

No information is available (either reported or derived from construction details) to populate the top- and bottom-depths of the screen interval. No record will appear in the D_INTERVAL_MONITOR table.

Assumed Screen (‘Top of ?’ Information Only) (123)

From borehole construction information, only a ‘Top of ?’ value is available (e.g. a top of plug depth has been specified but no depth). In this case, a 1ft (0.3m) screen interval is assigned below this depth.

Temporary Test Interval (124)

These intervals were only valid for a short time during well construction and/or development and were subsequently removed.