Dear Authors,

The two expert reviewers both noted the strengths of this work, which has shed new light on floodplain processes in organic carbon transfer through regions of permafrost. Thank you for your responses to the reviewers comments during the discussion period.

Given the nature of the comments from reviewers 1 and 2 regarding the mixing model that was formulated and applied, I sent the revised version to one of them with a brief to focus on this important aspect. They have completed their assessment and were satisfied with the revisions made, as was I. Thank you for carefully considering this point and re-analysing your data and making thorough changes to the linked discussion.

Having read the revised manuscript I am happy to recommend that this work is accepted pending technical corrections:

Line 180 (tracked changes version) - add a note after Equation 2 to spell out f_bio and f_petro (i.e. "where f_bio and f_petro are the fraction of organic carbon from biospheric and petrogenic sources", or similar)

Line 560 - the sentence implies that woody material in has been specifically sampled and targetted. Please rephrase. Also, could this be plant debris, not necessarily wood? (also see elsewhere where the term wood is used).

Dear Madison M. Douglas and team,

I am happy to convey that your manuscript has now been accepted for publication after the small technical correctsions indicated by the Associate Editor Bob Hilton.

Thank you for considering ESurf,

Andreas Lang