Ontologies

Each of the graphs in the SAWGraph project is built upon a set of ontologies that define the structure and relationships within the data. Ontologies define the concepts and categories and how they relate. SAWGraph reuses and extends existing ontologies to ensure consistency and interoperability across datasets. Each graph also has dataset specific ontology extensions that preserve the original data structure and semantics while aligning it with the overall SAWGraph framework.

Ontologies Overview

SAWGraph (PFAS) KG

Ontology	Description	Source	Documentation	Publication
The Contaminant Observations and Samples Ontology (ContaminOSO)	The core ontology for the SAWGraph knowledge graph, defining key concepts and relationships related to environmental sampling and release of contaminants. An extensions of SOSA	Github	ContaminOSO	[1]

FRS KG

Ontology	Description	Source	Documentation	Publication
Facilities and Industries Ontology (FIO)	Concepts and relations between facilities, industries and organizations	Github	FIO	[2]
Facility Registry Service	Dataset ontology for EPA Facility Registry Service	Github
North American Industry Classification System	Dataset ontology for NAICS industry classification	Github

Spatial KG

SAWGraph uses topological enrichment with S2 and Administrative Region 3 (county subdivisions and towns) in order to semantically link data in all graphs via their location. This is further outlined in our paper [3]

Ontology	Description	Source	Documentation	Publication
SAWGraph Spatial Ontology	A KWG-Ont extension that simplifies querying of spatial predicates by adding a superproperty for all spatial relations (excluding disjoint)	Github
KnowWhereGraph Ontology	Ontology for representing and querying geospatial data (Administrative Regions, Precomputed Topological Relations)		KnowWhereGraph
GeoSPARQL	OGC standard for representing and querying geospatial data on the Semantic Web	OGC	GeoSPARQL

Hydrology KG

Ontology	Description	Source	Documentation	Publication
SAWGraph Water Ontology	Ontology for representing both surface and groundwater. Combines concepts from HY_Features, HYFO, GWML2 and alsoaligns to Geoconnex.	Github

DSSTox

Ontology	Description	Source	Documentation	Publication
DSSTox Ontology	Ontology for representing chemical substances and their properties based on the DSSTox database structure	Github		[4]