Multiple text selections

We need to have multiple selections of text in a table cell and to make things more challenging, these can be different colors and lastly, they might over lap each other.  So really this can't be "selected text" but some type of an underlay layer of rectangles.

This will be in a table that will have 1000s of rows so performance is also a consideration.

Here's an example where:
Green spans "one (1) pipeline in one (1) trench,"
Orange spans "place one (1) pipeline"
Blue spans "one (1) trench"