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Entity Name: SWP Wellhead Protection Area
Table Name: SWP_WELLHEAD_PROTECTION_AREA_FT
Land area around a well where contaminants from land activities can reach and pollute the well water supply. Subdivided concentrically to show risk; scores range between 2 (lowest) and 10 (highest). In general, 8 or 10 indicate there is a policy for certain activities to prohibit or manage them. Wellhead protection areas are described as WHPA A: Area closest to the well, within a 100-metre radius. Land-based activities here pose the highest risk to well water. The vulnerability score is always 10. WHPA B: Contaminants from land-based activities in this area would take less than 2 years to travel to the well. Scores range between 6 and 10. WHPA C or C1: Contaminants would take less than 5 (C) or 10 (C1) years to travel to the well. Dense non-aqueous phase liquids (DNAPLs) continue to pose a threat here. The vulnerability scores range between 4 and 8. WHPA D: Contaminants would take up to 25 years to travel to the well. The vulnerability scores range between 2 and 6.
# | ATTRIBUTE/COLUMN NAME | DATATYPE | REQ | DESCRIPTION |
1 | OGF ID OBJECTID | NUMBER(13) | Yes | A unique numeric provincial identifier assigned to each object. |
2 | Source Protection Area ID SPA_ID | NUMBER(2) | Yes | Identifier for the source protection area that provided the original data about the feature. |
3 | Wellhead Protection Area ID WHPA_ID | NUMBER(13) | Yes | The object identifier of the feature from the original Wellhead Protection Zone dataset. |
4 | Area Name AREA_NAME | VARCHAR2(2) | Yes | The name of the well head protection area or zone, as a letter code. Values usually reflect the time period for water to reach the well. Code values are described as A: 100 m radius around the well, B: up to 2 years, C: up to 5 years, C1: up to 10 years, D: up to 25 years. VALID VALUES: A B C C1 D |
5 | Wellfield | VARCHAR(50) | No | Local name of water system |