'Difficult' Millyard Restoration Decision Goes to Aldermen

The Finance Committee, set to meet Aug. 7, will discuss what to do about the rebuilding and restoration of the iconic Millyard chimney as part of the city's Broad Street Parkway construction project, after none of the bids received for the chimney work came in under budget.

According to a memo attached to the Finance Committee agenda for Wednesday's meeting, bids were solicited from six firms after being advertised on August 28, 2012. Seven vendors attended a pre-bid meeting. Two proposals were received and opened on September 20, 2012. The project was re-bid for qualifications under RFP0208-022713 and advertized in both The Nashua Telegraph and Union Leader on January 13, 2013. Another mandatory pre-bid was held on February 7th. Three proposals were received and only one was deemed qualified, from the International Chimney Corporation out of New York. That submittal would restore the chimney to 180'. Various alternatives for height are listed below:

180-feet: $921,700
165-feet: $762,300
150-feet: $763,073
120 feet: $677,800

Mayor Donnalee Lozeau also included a memo with the Finance Committee minutes saying that the "difficult decision" will go back to the Board of Aldermen, and that keeping the project on budget has been a priority, including requesting the the Department of Transportation renew a federal funds program that has been designated for the work:

From the mayor's memo:

"We have established an aggressive schedule with the primary purpose of minimizing cost. As I have indicated, if we find that our schedule is so aggressive that we may incur additional cost rather than save costs, we will adjust the schedule. Cost control remains our primary focus.

"Recently, NHDOT notified us that immediate action is needed on this chimney contract due to time limits on the federal funds programmed for this aspect of the work. I believe that the decision to be made on this chimney is too important to allow time constraints to be imposed unless absolutely necessary.

"For this reason, we have requested that NHDOT work with the Federal Highway Administration to reprogram these funds to be used on a future parkway contract instead of the chimney contract. NHDOT has agreed to this adjustment in funding and confirmed that this adjustment only pertains to individual contracts and will not reduce the level of overall federal funding for the Parkway."

Eighteen months ago, Alderman Jim Donchess highlighted the issue of chimney restoration via his Facebook page when the old boiler house demolition project was underway, calling the chimney "a symbol of the Nashua Millyard for more than 100 years."

Lozeau is including the matter on the Aug. 13 Board of Aldermen agenda.

To get an idea of the scope of the restoration, below is an excerpt of the proposal submitted by International Chimney, included with the Aug. 7 Finance Committee Minutes:

"Below we've outlined our technical approach for the above mentioned project. Understanding that additional investigations must be performed, this should not be considered the final scope of work. In that this is a Preservation project we will follow the Secretary of Interior's "Standards" while performing all Technical Approach:

1. The chimney shall be rigged with an "International" repair bracket chimney scaffold.
2. A structural evaluation will be preformed first by a trained crew of International Chimney personnel. Field measurements will be taken including all wall thickness at various elevations. The liner will be examined for stability and removal. Ash will be tested to determine content and method of disposal. The crew that will be performing this work will be in contact with the project manager and the chief engineer.
3. Once all data has been recorded engineering will re-evaluate the above subject chimney. Our preliminary evaluation of this chimney indicated that the chimney can be reinforced by guniting (pneumatically applied concrete and sand mix) the interior, which would add strength to the column in order to meet current wind load codes. This method would not require any ongoing maintenance. Periodical inspections should be preformed one year after installation and every three years thereafter.
4. The existing lining would be removed by piecemeal removal from suspended scaffolds installed at the top and dropped down the interior for removal thru the openings at the base. The weight reduction of removing the existing lining would be an approximate offset of the weight new guinite lining on the existing foundation.
5. The seismic criteria for a structure of this height cannot be met, given the existing construction of unreinforced masonry. While normally historic structures are "grandfathered" against code, we understand the concerns relative to the chimney's close proximity to the future highways. The seismic situation would be somewhat improved (but not close to the degree required by code) by the repairs and the lining, but if deemed necessary to pursue, a variance to the code is necessary.
6. We are assuming that the existing foundation consists of a granite block foundation resting on dense soil. At this time however, the size and condition of the existing foundation is unknown. Once the initial masonry stabilization is performed we strongly recommend digging a test pit adjacent to the existing foundation (by others) to verify size and condition; before the more expensive repairs are performed. If the foundation is found to be substandard, remedial options could be considered, which might include relocation of the chimney to a different (less exposed) location and construct an adequate foundation.
7. If the gunite wind-load reinforcing plan is selected, the interior of the chimney would then be cleaned by either pressure washing or sand blasting to reveal a good sound substraight prior to guniting.
8. Steel steer horn anchors will be installed into the brick wall to which we will attach mesh. Long anchors would also be installed (epoxy) into the floor or foundation to which mesh will be attached. Then an application of a bonding agent would be applied prior to the gunite. Gunite would be sand and cement premix and the thickness would be determined by the engineering study.
9. Note that all interior work is intended to strengthen the chimney and will not be visible from the exterior. This work is not part of the original design and is not covered by the "Standards".
10. On the exterior, a significant portion of the existing mortar joints require restoration. While rigged, samples will be taken of (what we can identify as) the existing mortar and sent for testing. A suitable mix design will be developed that will mimic the existing mortar consistency and coloration. It is important to ensure that the mortar is not too hard for the brick. The workmanship of the existing joints will be examined and the tooling shall match as close as possible to the existing. Special care will be taken not to damage the brick units while removing old mortar. We use Arbor-Tech mortar saws as opposed to grinders which can remove the mortar with greater precision and have small saw blades for working on head (vertical) joints.
11. Significant cracks, such as found around the breeching opening shall be cut out and previously salvaged brick used to stitch gaps larger than 178th inch. Below 1/8th inch, either colored sealant or grout will be used to infill the cracks thru masonry units.
12. The exterior would then be rebuilt utilizing the bricks that were salvaged during the previous dismantling. Suitable back up brick would be located and used. These brick would be of the same size and hardness as possible. Mortar to be used would be similar to that used in the original construction. Chimney will be brought to its original height.
13. A monolithic cast in place steel reinforced concrete cover will be installed over the chimney top. This cover would be vented in order to allow the chimney to breathe and prevent interior condensation. There will be also a hatch installed for future inspections.
14. The existing lettering will be re-painted as specified.
15. The existing Lightning protection system shall be shall be replaced in kind. 16. We advise against putting on a waterproofing agent as this would tend to entrap moisture on the interior, especially with the cover installed. The masonry is too thick walled and will retain moisture. The result of moisture entrapment can include effervescence; rapid degradation of mortar and spalling of brick faces.
17. As the work is completed, the site shall be picked up, all tools and equipment removed and left in a "broom clean" condition.

What do you think the city should do about the chimney?