I am not sure how you will get the two TOCs to be side-by-side but, I would create each TOC separately following the normal TOC construction process for each TOC using this link as guidance:

http://www.shaunakelly.com/word/numb...l#CreateTheTOC.

The only difference being that using the styles "Heading 1, 2 and 3" for the Header Level 1 TOC and the using the styles "Heading 5, 6 and 7" for the translation level 1 TOC (or some variation thereof). Of course, you would have to modify the behavior (font, line spacing, et al) of each style so that they match each other. However, if you have other requirements for a TOC in the same document (i.e., a TOC for Appendicies), it may become restricted somewhat.

This is my opinion only, others on this board may offer other/better solutions of their own (in which I would be interested in learning as well).

Hope this helps.