Locations and field artifacts
A Location is a monitored or sampled point within a Site — a well, a soil boring, a pit, or a coring station. Each Location can be realized as a physical subsurface feature called a field artifact: a Well, a Borehole, a Test Pit, or a Sediment Core. The artifact holds the construction and logging detail; the Location holds the identity, coordinates, and status that the rest of the system references.
What a Location is
A Location is the addressable point on a Site. It carries the things that stay true regardless of how the point is physically realized: a Code (unique within the Site, max 50 characters), an optional Name, a Location type (LocationTypeId), a Status, and its spatial and elevation data.
A Location is an aggregate root in its own right, not a child of any single artifact. Its coordinates and elevation live on a child set of measurements (one Location can hold several, with one marked primary), so survey re-measurements accumulate over time rather than overwriting.
Status values (LocationStatus):
| Value | Meaning |
|---|---|
Active | In service — part of the active sampling program |
Inactive | Temporarily dormant but physically present and re-samplable |
Proposed | Planned, not yet physically established |
Decommissioned | Terminal — plugged, abandoned, or destroyed |
A Location starts as Active. Setting Decommissioned pairs with a decommissioned date; recording that date requires the Decommissioned status.
Field artifacts
A field artifact is the physical record of how the point was constructed or logged. The four types are separate aggregate roots that each reference their parent Location, so a Location's feature set is determined by which artifacts actually exist there — not by its chosen Location type.
Figure: a Site contains Locations; each Location may be realized as one or more field artifacts. The application keeps a Test Pit or Sediment Core to one per Location; the database does not enforce this.
A Location is often realized as a single artifact. The exception is drilling: a Well and a Borehole can coexist at one point (a well is frequently completed inside a logged borehole), and you can record more than one of each. A Test Pit or a Sediment Core, by contrast, occupies its Location exclusively — once one exists, the feature set is closed.
Comparing the four types
Every artifact shares a Code (unique per Site), a Status, and optional notes. They differ in the construction and logging detail each one captures.
| Artifact | What it is | Distinguishing data |
|---|---|---|
| Well | A constructed groundwater or monitoring well — a hole completed with casing and, optionally, screen | Measuring point: top-of-casing elevation with a vertical datum and stickup height. Casing intervals (casing, screen, sump) with depths and diameters, plus annular intervals (filter pack, seal, grout, backfill, other) with depths and placed quantity |
| Borehole | A drilled or bored hole logged for stratigraphy and sampling | Drilling dates and method; refusal type; lithology intervals; sampling runs (with recovery); point-in-time groundwater observations |
| Test Pit | A shallow machine- or hand-excavated pit or trench | Excavation method, dimensions (length, width, depth), termination reason, backfill detail; lithology intervals and groundwater observations |
| Sediment Core | A sediment core taken by push or drop methods (typically marine or lacustrine) | A required depth range from the sediment-water interface downward; recovered length; lithology intervals; storage location and disposal tracking |
Status defaults differ by type: a Well, Borehole, or Sediment Core starts Active; a Test Pit starts Open. Each type also carries its own set of status values, including one or more terminal states. A Well or Borehole can end as either Decommissioned (formal, protocol-compliant sealing) or Abandoned (walked away from, with no sealing record); a Test Pit ends as Backfilled; a Sediment Core ends as Disposed.
The full status set per type:
| Type | Status values |
|---|---|
| Well | Active, Inactive, Proposed, Abandoned, Decommissioned |
| Borehole | Planned, Active, Completed, Decommissioned, Abandoned |
| Test Pit | Planned, Open, Backfilled, Abandoned |
| Sediment Core | Active, Archived, Disposed |
Top-of-casing elevations and vertical datums
A Well's Top of Casing elevation must resolve to a vertical datum — an elevation without one is ambiguous, because NAVD88, NGVD29, and local mean-sea-level datums differ by up to a meter. When you enter a top-of-casing elevation without picking a Vertical Datum, Erde falls back to the Site's default datum; if the Site has no default either, the save is rejected: "Select a vertical datum or set a default on the site."
Historical well inventories often carry top-of-casing elevations whose datum is genuinely unknown. Keep those elevations rather than dropping them, and do not guess a real datum: add a Vertical Datums reference-data entry for the case — for example Code UNKNOWN, Name Unknown / assumed local datum — and assign it to those wells. Elevation comparisons across datums are only as good as the datum records, so an honest unknown preserves the data while flagging that its elevations should not be mixed with surveyed ones.
How it fits together
You reach a Location's artifacts on its Features page (in the Location's left navigation). The page shows one section per existing artifact type — Well, Borehole, Sediment Core, Test Pit — under its own heading, and offers Add buttons for the types you can still add:
| Already present | What you can add |
|---|---|
| Nothing | Well, Borehole, Test Pit, or Sediment Core |
| A Well or Borehole | Another Well or Borehole only |
| A Test Pit or Sediment Core | Nothing — the feature set is closed |
When the Site is locked, adding features is blocked until it is unlocked.
Field artifacts hold construction and field-log data — they do not hold continuous monitoring streams. Recurring readings such as Water Levels, Well Purges, and Field Parameters are recorded through the Field Monitoring tools, not on the artifact itself.
Related
- Sites — the container that holds Locations and their artifacts
- Sites & Locations overview — the rest of this section, including adding Locations and artifacts
- Field Monitoring — recording Water Levels, Well Purges, and Field Parameters at a Location