Last updated: July 20, 2023
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Podcast 081: Getting Dirty With HACE
National Park Service
Conservation of Waterlogged Wood
Alex Beard: Hi, my name is Alex Beard. I’m here in the Northeastern Branch of the National Park Service in Lowell, Massachusetts with objects conservator Margaret Breuker. Today I wanted to ask her about an object that is currently undergoing treatment in the lab. It is an artifact that is historic to Boston and I wanted to know if she could shed some light on its rich history and the treatment it’s currently under in the lab.
Margaret Breuker: Sure Alex. This is a piece of the hoisting apparatus from the Bunker Hill Monument in downtown Boston, Massachusetts. It is two pieces of timber that are connected with iron pins and it was excavated in the 1980’s from the basement of the Bunker Hill Monument along with some other archeological objects, but this is the only engineering object that was excavated. And as far as we know, the only piece of engineering ever located that was used to build the Bunker Hill Monument. So it’s a very important piece.
It was waterlogged when it was excavated, which means that it was found completely submerged underwater. Now that makes it a challenging piece to conserve because when wood is waterlogged, the wood cells become filled with water and it overtime degrades the cellulose in the wood cell replacing it with water so that all of the cells of the wood become filled with water and that provides the structure for the wood. So that when you excavate it and take it out of that water it has no structure if you remove it from the water environment. So when you excavate waterlogged wood or any material made of cellulose, you have to keep it waterlogged until you can treat it. And this has an interesting treatment history where it was kept actually in a tank of water for many, many years and it wasn’t until the 90’s where it was left to slowly dry out in dark storage. And it was brought to me this year, 2016, to conserve only after it had dried out over a long period of time.
Alex Beard: Would you say that the wood is stable now?
National Park Service
Margaret Breuker: It’s stable in that it is no longer filled with water, but it’s very, very fragile, and very, very dry, and the iron elements are very, very unstable as well as the iron when it is buried starts to revert back into its elemental state. It’s now probably closer to an iron(III) which is a very unstable state. It’s very friable, so that also needs to be consolidated. What we need to do now-
Alex Beard: It’s essentially rust now. It’s not even-
Margaret Breuker: Yeah, it’s very orange looking and it is very weak, has no real strength anymore. Same with the wood, it’s also very weak. So what we’re going to do is we have to consolidate, it’s called, both the iron and the wood with a consolidant. It’s going to be different consolidants for the iron and the wood because they’re very different materials. So we’re going to replace the voids that is in the plant fiber with a material called methylcellulose that we’re going to spray onto the timbers and we also are going to consolidate the iron with a material called B-48, which is an acrylic used a lot on metals.
Alex Beard: So you’re mainly looking just to stabilize and preserve this interesting history of this object without trying to make it look brand new.
Margaret Breuker: Yeah. We couldn’t make it look brand new even if we tried, Alex, but we’re going to just keep it as stable as we can so that no more pieces of either the wood crumble or fall off or the iron. So that people can view it and see it for all of its interesting little notches and holes and pieces.
Alex Beard: How will the piece be displayed and where will it be displayed?
Margaret Breuker: It will be displayed in the Boston Navy Yard Museum and we’re going to create a mount for it that will be specially created just for it to support it underneath in locations that are the most stable for it and it will have an enclosure so that no one can touch it, but they can view it safely.
Alex Beard: If you’re ever in the Boston area you might be able to come and see this hoisting apparatus after it’s been treated. I will upload pictures onto the website so that you can view some before and after pictures of this piece. Thank you so much for your time Margaret. I appreciate it.
I’m here with another HACE object conservator, Carol Warner and she’s going to talk about a current project that she’s working on from Weir Farms in Connecticut and discuss the treatment and historical significance of the piece.
National Park Service
Plaster Relief Conservation
Carol Warner: Okay, well this is a plaster relief and it’s seven feet high by eleven feet and it’s a working model, was never a piece that was intended for exhibit. It’s one of the steps in the process of making a bronze. This particular piece is one of three pieces that would go end to end and it represents the trip of the Mormons across the country to establish their settlement in Salt Lake City, Utah.
The bronze that we’re talking about that this plaster would have facilitated the fabrication of is on the side of this very large monument called This Is The Place Monument and it’s tall granite obelisk and it has figurative groups, oversized figurative groups in bronze in these relief panels along the sides. And this would be the model that would be sent to the foundry where they would make another mold and then they would make the bronze.
So the relationship of this piece to the park, this comes from Weir Farm National Historic Park. Mahonri Young was the son-in-law of J. Alden Weir, who the park is named after, the American Impressionist painter. Mahonri Young was the grandson of Brigham Young, the head of the Mormon movement. That’s why this piece is a part of the Weir Farm Collection. This piece was stored in a barn. It had it’s useful life but the artist chose to save this, actually most of these panels, there’s six all together that fit together to form two long reliefs.
Alex Beard: Could you tell us a little bit about the condition of the plaster relief and what the treatment will involve?
Carol Warner: Yes, the condition is the effect of it being stored by the artist in a barn with no protection for many years. He chose to retain these working pieces. Three of them are in fairly good condition in that they’re mostly complete. Some of them are missing major figurative pieces. But the result of being stored in the barn, the main damage to it was water continually ran over the plaster surface and water erodes plaster. So there were lots of streaks and pits and losses of the surface on this particular piece. And then at a certain point when the park service took over, this piece was crated and then it was kept from any further deterioration for many years and was surveyed by our conservation group in 1995. So we did see the condition of it and then it finally has been funded for treatment and we’re treating it now. As we open the crate the condition is similar to what it was when it was crated by the park service.
It basically needs to be totally surface cleaned because it has a lot of surface dirt. We use white vinyl erasers to clean it because the plaster is extremely porous and if you would use any kind of liquid it would force the dirt in instead of take it off. Part of the work will consist of replacing some lost pieces in the erosion areas and we’re working with a fill material. It’s a variation on B-72 acetone microballoons. In this case we’re using 40% B-72 acetone and bulking it really thickly with microballoons and then tinting as needed. So with that material we are reconstructing the loss and we are filling the areas of erosion. We have to reconstruct ox horns, horse ears, some of the landscape.
Alex Beard: I hear that the previous two plaster reliefs that you worked on for the This Is The Place Monument will be on display at Weir Farms, but this one will not?
National Park Service
Carol Warner: Yes, the other two are currently on display in the Young studio and one of those two actually has Brigham Young in a coach. This is a part of one relief, those two are part of another relief. But anyway, they’re on exhibit and then will be stored until the park is ready to exhibit it and this one will be exhibited in the barn because they don’t have room to exhibit another large one in the Young studio.
Alex Beard: Thanks Carol for discussing the project with us. We appreciate it.
Now I’m speaking with Johnny Holdsworth who is also assisting Carol Warner with the Weir Farms project. He’s had a really interesting past with the National Park Service and has been in multiple geographic locations and worked on many different projects and I’d like to see if you could talk to us a little bit about your past and some previous projects you’ve worked on.
Projects: In-House & Contracting
Johnny Holdsworth: Sure, I started with the National park Service in 2009. I started out in New Mexico as an archeological technician at Bandelier National Monument and out there we would do restoration and preservation work on Native American ruin sites.
Some of them are in cliffs or just in the main canyon there. So a lot of masonry restoration work there but also some graffiti mitigation on ancestral Puebloan art that’s inside the spaces that are still surviving. So I did that for a number of years. A short stint after the Deep Water Horizon oil spill as an archeological resource advisor down at the gulf.
And not too long after that I had an offer to work for HACE up in New York City. Up until about 2013 I worked for Bandelier and then I moved to New York City working for HACE. With HACE I work as a preservationist and that job puts me anywhere potentially in the northeast doing restoration work.
Some of it’s down to the nitty gritty doing reroofing projects or tuck pointing. It kind of varies but I also do a bit of construction management or contractor management as a contracting officers representative.
I oversee some of the contract work that the government hires for different restoration work. So some of that work has taken me anywhere from upstate New York to here in Massachusetts right now, some work in Pennsylvania. It could be really anywhere but the projects are all varied, anything from fixing up somebody’s roof, or doing masonry restoration, or in this case doing preservation work to a sculpture.
Alex Beard: So where is Bandelier National Park located?
Johnny Holdsworth: Bandelier National monument is in Los Alamos, New Mexico. So it’s right next to the national lab and it was established for the resources there related to Native American occupations.
Some of the sites there date, some of their earliest stuff is right around 1100 up to around 1450. A number of the sites are actually excavated out of the sides of canyon walls. So they’re these spaces called cavates where Native Americans carved them out and made them into living working spaces.
So those are some of the primary resources at that park. And there’s also a number of CCC buildings in the historic district that all date to the 1930’s just prior to the Manhattan Project taking over the Los Alamos area. Some of those buildings were occupied during Manhattan Project for scientists working at the lab doing atomic testing.
Alex Beard: How many National Park sites have you been to would you estimate? Because it seems like you’ve traveled a lot for your job and that’s super rewarding and you’ve gotten to see so many different parts of the United States.
National Park Service
Johnny Holdsworth: Yeah, I have to recount. I’m somewhere around 120 park service sites now and there’s as of yesterday I think there’s 411 or 412. So I’ve been to at least a quarter of them now.
A lot of those I just visited as a casual visitor but probably about two dozen of them now I’ve actually worked at or had projects at. I’ve had a project at Yosemite one time, I’ve done a number of projects in the Southwest, a couple of random projects that I got to do with HPTC, the Historic Preservation Training Center out of Frederick, Maryland.
I did their preservation skills training a few years ago. I finished up last year. It’s a two year training program. So that gave me the opportunity to go and train at other parks and see how they do preservation work.
Those projects range anywhere from, again, Yosemite to Harper’s Ferry in Cape Cod, we were in the D.C. area for a little bit, back down actually into Southern California for one of those projects. That was a great opportunity to see preservation around the country with the park service and meet a lot of other people that do similar work.
Alex Beard: Can you tell us about a couple future projects that you have in store?
Johnny Holdsworth: Yeah, I’ve got a project lined up for later on this summer up at Marsh-Billings-Rockefeller, that’s in Woodstock, Vermont and one of the resources there is there’s an underground fallout shelter dating to the early 60’s that was installed by the Rockefeller family.
Overall it’s in really good shape but some of the bottom of one of the, or two of the shelters that are underground is starting to rust out. So we’re going to do some metal conservation work on those spaces, but even though it’s kind of straightforward in the sense that it’s going to be stabilizing the surface and coating them to prevent further rust, the location underground and limited air kind of makes it a more technical project for working in a small space and with limited oxygen.
It will be a matter of going over with a conservator what we want to use and then figuring out how that might impact the limited environment we have in coming up with a good safety plan for myself working in that space. So that’s one of the big upcoming projects I’ve got.
I’ve got another ongoing project in New York City working on Hamilton Grange, which is Alexander Hamilton’s house. There’s some restoration on his outdoor portico porches. So there’s a little bit of work there and wrapping up some work at Castle Clinton in Battery Park in New York City.
We’ve got a contractor finishing up work on some of the stone magazine, powder magazine roofs there. Lots of work, always varied, and in different places but that’s what makes it interesting is that every project’s a little different and in a different place.
Alex Beard: Well thank you Johnny. I look forward to hearing about the work you’re going to continue to do for the National Park Service.
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