When a Boundary is selected the SELECTION - TOOLS menu will be available. The SELECTION - TOOLS menu contains tools that allow you to edit, change styling, annotate, or perform advanced functions on your Boundary. 

Individual Boundary selection

Multiple Boundary selection

Tools group

Select WithinSurvey (Point, Polyline, Boundary, Surface) and Measurement items inside the selected boundary will become selected. 

Styling group

LineAllows you to change the Boundary line color. 
ThicknessAllows you to change the Boundary line thickness.

Annotate group

NameBoundary Descriptor & Number displayed over the Boundary in the Viewport.
LabelAllows you to change the Boundary Label color.
SizeAllows you to change the Boundary Label size.

Edit group

Edit VertexEnables Edit mode for selected boundary. Displays the Edit Vertex Mode box where you can select editing options and check individual vertices X,Y,Z coordinates.

Transform group

To TerrainSelected Boundary will be draped to the underlying Elevation terrain by changing the Z value of the vertices to the same elevation as the Z level of the terrain at their XY location. 
SplitEnables Split mode. The Boundary can now be split into Polyline items that can then be reassembled to your needs. Left-mouse click at the start and ending locations along the Boundary where you would like to split the boundary. Two Split locations must be chosen to split a Boundary. If only one is chosen, the boundary will only add a vertex that will be used as the first input if the Split mode is used again.

DensifySelected Boundary will become more complex by adding vertices to it that drape the Boundary to the underlying terrain. Densify has 2 methods of adding vertices, Break Points & Regular. Breakpoints will add vertices by elevation change along the Polyline, while Regular will add vertices at a specified interval. All vertices created will always drape onto the underlying terrain.

Create group

Offset LineCreates concentric boundary items to the selected Boundary. A Z Offset can also be applied via the dialog box. Left mouse click in the Viewport determines the offset distance.

Result: Boundary
Extract PointsCreates Point items at every vertice of the selected Boundary.

Result: Point(s)
Triangulate WithinCreates a Surface item utilizing all active survey items within the selected Surface.

Result: Surface
Create WaterCreates a Water item within the selected Boundary that has it's water level set to the highest vertice of the Boundary.

Result: Water

Volumes group

Volume DifferenceCreates a Cut/Fill map within the selected Boundary between the current Terrain State and another Terrain State selected into the Reference State box. This functionality only appears when you have a boundary selected AND multiple terrains states available.

Result:  Volume

Terrain group

Offset WithinShifts the Elevation terrain's Z value within the selected Boundary according to the amount entered into the Level box. Shift can be a positive or negative value.