Add additional CompareOperations http://github.com/ngageoint/geowave/blob/master/core/geotime/src/main/java/mil/nga/giat/geowave/core/geotime/store/filter/SpatialQueryFilter.java#L50 for all spatial relationships listed here as "geometric predicates" (the JTS library provides all of these predicates):
http://docs.geoserver.org/latest/en/user/tutorials/cql/cql_tutorial.html#geometric-filters

If the predicate has additional implications on the minimum bounding box for the query ranges SpatialQuery will need to be modified appropriately
http://github.com/ngageoint/geowave/blob/master/core/geotime/src/main/java/mil/nga/giat/geowave/core/geotime/store/query/SpatialQuery.java

In particular getIndexConstraints() from its parent class BasicQuery will be changed: http://github.com/ngageoint/geowave/blob/master/core/store/src/main/java/mil/nga/giat/geowave/core/store/query/BasicQuery.java#L175