Hi Julie,
I received some very thorough feedback for you from conservator Ellen Carrlee at the Alaska State Museum. Let me know if you want me to dig further or get any follow up from Ellen. Here's Ellen's advisement to you:
"There are three challenging factors here, one is the fragility of newsprint, another is the harshness of the outdoor environment, and a third is an imaginary "perfect coating" that would mitigate the other two. I would not recommend accessioning this into the collection, especially if they intend to repurpose it and have it outdoors, since preserving it is so challenging. If they really want to keep it as part of their collection, they would need to commit to an indoor option. Newsprint has a high lignin content, is among the most acidic and poor quality of all paper, and deteriorates even in good museum conditions. Constant exposure to the also-acidic wood, temp/RH changes, very high light levels, exposure to water, etc make preservation outdoors on a log really tough. Engineering and application of a coating that will prevent all moisture from getting in and prevent any moisture from being trapped under the coating is really difficult. All coatings break down over time, especially with UV exposure, and need to be removed and re-applied (this is from long legacy of bronze sculpture preservation outdoors, lots published about that). Even the most delicate archival coating applied to paper is very difficult to remove under the gentlest circumstances. A robust, waterproof, UV-resistant coating on paper will be impossible to remove and re-apply. Outdoors, coating it will destroy it eventually, and not coating it will destroy it quickly.
The institution needs to articulate its long-term goals with this item and design a solution to address them. Perhaps there is a really appealing section of log with particularly exciting newpaper attached, or maybe diagnostic tool marks...maybe this portion is a size that might be worth cutting down to reasonable dimensions and keeping in the collection? Assuming the institution decides this is something going outside with a finite life span, perhaps 10 years, and is an education piece for consumptive use, then going with the most robust clear waterproof outdoor coating possible and locating the display in a protected area out of direct sunlight would give the best chance to last for a while. In that case, calling around to paint stores for advice on commercial products will be best. Things that are clear with UV protectants and hopefully something that resists yellowing would be good. Price is often an indicator of quality, so going with something more expensive will tend to give better results. My degree of confidence in a product would go up if the paint store person took a nerdy interest in the question. The log will outlast the newspaper, so making good photodocumentation of the newspaper might allow reproduction newspaper to be attached to the logs in the future? Of course, the logs themselves will last longer with treatment, too. Avoiding direct contact with the ground, applying borates, and a water repellent could well keep those outdoors for 20 years or more. Beware the end grain, rot will start there first."
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Lissa Kramer
Washington State Historical Society
lissa.kramer@wshs.wa.gov------------------------------