Ultraflourescent image of page 1, before treatment, showing glassine tape and other damage

This decision -- a sound one for the time -- did not impede the further chemical deterioration of the declaration nor do anything to address the weakness of the paper along the folds. By 1999, when conservators stepped in, numerous paper repairs had accumulated across the folds and along the edges in attempts to stabilize and strengthen the two leaves, and as a possible result of condensation between the panes of glass, the paper had cockled and become heavily discolored. Worst of all, under some unknown set of circumstances, severe water damage had occurred on the second leaf resulting in the mobilization of the (unfortunately) water soluble ink and the loss of some text. Unsightly water stains and harsh "tidelines" further impaired visibility. Small paper losses were noticeable at the intersection of the folds and along the edges.

Thus, after careful examination, the conservators decided to remove the Jefferson draft from the glass and wooden enclosure in which it had been housed for over 150 years and treat the document to stabilize it and prevent further deterioration. The treatment included surface cleaning of the leaves with grated vinyl eraser and a soft brush. The glassine tape along the folds and margin was removed using poultices of methylcellulose and enzyme, and adhesive residues were reduced by swabbing around the text with cotton tips moistened with deionized water and ethanol. The tidelines were reduced using dilute ammonium hydroxide. The disassembled leaves were immersed in successive baths of ethanol and deionized water and the pH was adjusted to 7.5 with calcium hydroxide.

Small tears and losses were mended using acrylic and pastel-toned Tengujo (Japanese paper) adhered with cooked wheat starch. The reconstructed leaves are now housed in a state of the art sealed package to isolate them from atmospheric pollutants.