Sites and site areas
A Site is the spatial scope in Erde — a single managed physical place, such as a former industrial property or a landfill. Everything spatial hangs off a Site: its Locations, the field artifacts beneath them, and the environmental data collected there. A site area subdivides a Site into named sub-areas (operable units) that close out on their own timelines.
What a Site holds
A Site is the top-level spatial container — an aggregate root that owns Locations, site users, contacts, registrations, and site areas. Its identity is the Code: a short, unique label (Code is unique across all Sites; Name is descriptive and is not required to be unique). You classify a Site by Site Type (a reference data value) and track its lifecycle with Status.
A Site carries two land-use fields by design — Current Land Use (what is there now) and Intended Land Use (what cleanup targets). Risk-based screening levels depend on the intended use, so the two are tracked independently.
| Field | Type | Required | Description |
|---|---|---|---|
| Code | text | Yes | Unique identifier, up to 50 characters. Carries the Site's identity. |
| Name | text | Yes | Descriptive label, up to 200 characters. Not unique. |
| Site Type | reference data | Yes | Classification; must be active. |
| Status | enum | Yes | Lifecycle. Defaults to Active. |
| Current Land Use | enum | No | What occupies the Site now. |
| Intended Land Use | enum | No | The cleanup goal that drives screening levels. |
| Start Date / End Date | date | No | Operating range. End Date requires Status of Closed. |
| Address fields | text | No | Address Line 1 / Address Line 2, City, County, State, Postal Code, Country. |
| Coordinate | point | No | Site location, always stored in WGS84 (World Geodetic System 1984; EPSG:4326). |
| Boundary | polygon | No | Site outline, managed through dedicated boundary editing. |
| Coordinate System | reference data | No | Default working frame for child geometry. |
| Vertical Datum | reference data | No | Default vertical reference for child geometry. |
| Area / Area Unit | number + enum | No | Set both or neither. |
| Time Zone | text | No | System time-zone identifier (IANA — Internet Assigned Numbers Authority — on Linux/macOS, Windows IDs on Windows). |
| Description | text | No | Free text, up to 2000 characters. |
The Site's own representative Coordinate (its map pin) is always in WGS84. The Boundary can be entered in any coordinate system — you pick it when editing the boundary, and Erde reprojects to WGS84 for the map (see Edit site and area boundaries). A separate Coordinate System and Vertical Datum set the default working frame for child geometry (Locations, Wells), so a Texas Site can default its features to a State Plane zone without changing how the Site point itself is mapped.
Status values
| Value | Meaning | Notes |
|---|---|---|
| Active | Operating Site under management | Default for a new Site. |
| Closed | Regulatory close-out | Pairs with End Date. |
Land use values
Both Current Land Use and Intended Land Use draw from the same set: Residential, Commercial, Mixed Use, Industrial, Agricultural, Recreational. There is no "Unrestricted" value — that is a regulatory cleanup outcome, not a land use.
Site areas
A site area is a named sub-area of a Site — an operable unit. Because different parts of one Site reach closure at different times, a site area carries its own Status, independent of the parent Site's status. Each site area also carries a Color so it reads distinctly on the map; the Site itself has no color.
A site area's Name is required and is unique within its Site (two areas on the same Site cannot share a name). You classify each area by its Type (a Site Area Type reference data value).
| Field | Type | Required | Description |
|---|---|---|---|
| Name | text | Yes | Unique within the Site, up to 100 characters. |
| Type | reference data | Yes | Classification (a Site Area Type value). |
| Status | enum | Yes | Defaults to Under Investigation. |
| Color | enum | Yes | Map color. Defaults to Blue. |
| Boundary | polygon | No | Area outline, managed through boundary editing. |
| Description | text | No | Free text, up to 1000 characters. |
Site area status values
| Value | Meaning |
|---|---|
| Under Investigation | Default for a new area; characterization in progress. |
| In Remediation | Active cleanup. |
| Monitoring | Post-cleanup monitoring. |
| Closed | Terminal; the area is closed out. |
Site area colors
A site area is one of 16 colors: Blue, Red, Amber, Emerald, Purple, Orange, Cyan, Pink, Teal, Indigo, Lime, Brown, Slate, Navy, Olive, Maroon. The default is Blue.
How it fits together
A Site contains Locations and any number of site areas. A Location can be assigned to any number of site areas (including none), which is how you tie a monitoring or sampling point to the operable unit it belongs to. The field artifacts — Wells, Boreholes, Test Pits, and Sediment Cores — live beneath Locations.
Figure: a Site contains Locations and site areas; Locations are assigned to site areas and may carry field artifacts (Wells, Boreholes, Test Pits, or Sediment Cores).
A Site is spatial; a Project is the work scope. The two are linked many-to-many: one Project can span several Sites, and one Site can be worked under several Projects. Data such as Samples and field measurements is scoped to a Project–Site pair, so the link must exist before that data can be recorded.
| Aspect | Site | Project |
|---|---|---|
| Answers | "Where?" | "Under what scope of work?" |
| Owns | Locations (and their field artifacts), site areas | Samples, Lab Reports, field measurements |
| Lifespan | Outlives any single Project | A defined engagement |
| Linked to | One or more Projects | One or more Sites |
For how the Site–Project link grants access and scopes data, see Sites and projects. For where Sites sit in the overall data model, see the data model.
Related
- Sites and projects — how the spatial scope and the work scope connect.
- The Erde data model — the full map of objects and how they relate.
- Locations and field artifacts — what lives beneath a Site.
- Sites and Locations — task guides for creating and managing Sites and site areas.