A number of factors spring to mind.
Is the carpet wool rich or synthetic? Were the boots sodden wet when cleaned or just surface wet? Were the boots a particularly strong colour? Could it just be dirty water dripping as opposed to dye? How far off the ground was the shelf as the drips will penetrate the carpet further the higher up the shelf was ? Is is a plain, light-coloured carpet?
Without some answers to these and probably other questions it's difficult to say. However if you push me into saying "yes or no" then I would think that a more than acceptable treatment of the drip marks is possible.
Roger