March 2018 page for PAL updates 2018-06-11T16:08:51+00:00

Public Archaeology Laboratory (PAL) – March 2018  

On behalf of National Grid, archaeologists from The Public Archaeology Laboratory, Inc. (PAL) monitored and recorded the demolition of the granite seawalls. The demolition work began in October 2015 and was completed in January 2016.

The historic data analysis, done in the summer and fall of 2017, confirmed that the granite seawalls were gravity-type structures composed of battered, dry-laid, split-faced granite blocks and stones, one-stone thick, with uneven or no coursing. The single stone vertical walls were reinforced with dense ballast composed of mixed-size cut stones and cobbles, reinforced with earth fill containing old timbers near the bottom of the wall. Some of the seawall capstones and upper granite blocks were anchored with 1-inch rounded wrought iron rods or pins for structural support.

The historic granite seawalls exemplify nineteenth-century stone seawall and wharf construction that required the highest quality granite and expert stone masonry cutting and fitting techniques. The granite would have been readily available and abundant in the local Cape Ann quarries around Gloucester.

Landward side of the granite seawall in Solomon Jacobs Park during demolition, showing the iron rod or pinning in the upper granite blocks (PAL photo).

Detail of iron rod or pinning in the upper granite blocks of the Solomon Jacobs Park seawall (PAL photo).

 

 

 

 

 

 

 

 

 

Cobble and stone ballast exposed on the landward side of the Solomon Jacobs Park seawall during demolition work (PAL photo).

Overview of the granite seawall demolition along Solomon Jacobs Park, showing exposed rock ballast and earth fill in the historic wharf area (PAL photo).

 

 

 

 

 

 

 

 

Remnant timbers in the lower fill deposits of the wharf behind the granite seawall in Solomon Jacobs Park (PAL photo).

Lowest course of granite stones visible at low tide at the corner of the granite seawall in Solomon Jacobs Park (PAL photo)

 

 

 

 

 

 

 

On behalf of National Grid, architectural historians from PAL oversaw the reconstruction of the granite seawalls in the remediation project area of Solomon Jacobs Park and the National Grid building lot.

The new seawall reconstruction began in January 2016 and was completed in the late summer of 2017. The new granite seawalls were designed and built to be compatible with Gloucester Harbor’s historical character and to meet stringent engineering requirements. The front faces of the new walls are battered and gaps between the face and backing walls are filled with chink stones and gravel.

The granite used in the new seawalls was salvaged on site during the seawall demolition and supplemented as needed to meet the historical design requirements. The seawall reconstructions involved the placement of new wood deck railings. New granite block benches made from materials salvaged during the demolition work were also installed in Solomon Jacobs Park.

Employees of Custom Stone Builders placing 18-inch-wide coping on the top course of the Solomon Jacobs Park seawall (PAL photo).

Completed seawall along the east side of Solomon Jacobs Park, September 2017 (PAL photo).

 

 

 

 

 

 

 

 

Top of the completed seawall and visitor seating area along the waterfront at Solomon Jacobs Park (PAL photo).

Almost completed seawall in front of the National Grid building, May 2017 (PAL photo).

 

 

 

 

 

 

 

 

Rear view of the National Grid building seawall under construction with poured concrete backing wall, May 2017 (PAL photo).

Completed granite seawall with wood railing in front of the National Grid building, September 2017 (PAL photo).

 

 

 

 

 

 

 

 

Completed seawalls at Solomon Jacobs Park and on the National Grid building lot, September 2017 (PAL photo).

 

 

 

 

 

 

 

 

 

 

 

 

 

PAL’s oversight work also included the reconstruction of the granite seawall on the nearby Maritime Gloucester property.  The remediation work required the removal of the top 4 feet of the wall, including the concrete cap and one course of granite blocks in front of the Maritime Gloucester boat house.  A new timber deck walkway was added on top of the seawall, which was made to look like the original seawall.  The reconstruction was done from February to April 2017.

Maritime Gloucester seawall before the addition of the timber deck walkway, April 2017 (PAL photo).

Completed Maritime Gloucester seawall with timber deck walkway, September 2017 (PAL photo).

 

 

 

 

 

 

 

On behalf of National Grid, PAL’s marine archaeologist from David S. Robinson Associates (DSRA) monitored, inspected, and recorded portions of the two historic marine railways as part of the harbor dredging operations.

Submerged portions of an inactive marine railway were exposed and removed from the harbor floor during the dredging operations. The inactive marine railway was the first and smaller of the two railways built in the Burnham Brothers Shipyard by the Crandall Dry Dock Company of East Boston. The railway was completed in 1849–1851 with an approximate length of 250 feet, and was used to repair vessels up to 500 tons until it was destroyed by fire in 1953. Following the fire, the shipyard owners abandoned the railway and left it to decay in place below the high water line.

The 2016–2017 archaeological monitoring work identified and recorded 50 individual railway elements, including wood rail sections, iron rail plates, wood bilge blocks, wood pier piles and a railway foundation pile, and wood cross-ties.

One of two intact rail sections (tipped on its side with underside visible) from the inactive marine railway.  Note the angled scarph joint at the end of the rail section. A scarph joint is a method of connecting two or more lengths of timber into a single structural unit. Matching tapers are cut in the mating ends of the wood and secured with iron nuts and bolts to make the structure stable (DSRA photo).

Iron rail plates preserved on the top surface of the recovered intact sections of the inactive marine railway’s wood rail (shown tipped on its side). Note the butt-joint and in-line double iron fastening of two track sections and the staggering of joints in two runs of track (DSRA photo).

 

 

 

 

 

 

 

 

 

 

Lowermost bilge block timbers with flared bases recovered from the inactive marine railway (DSRA photo).

Lowermost bilge block timbers with flared bases recovered from the inactive marine railway (DSRA photo).

 

Possible rail foundation pile (with sharpened end) recovered from the inactive marine railway (DSRA photo).

 

 

 

 

 

 

 

 

 

 

Cross-tie recovered from the inactive marine railway (DSRA photo).

The single iron fastener hole near the end of the timber where the rail was fastened to the cross-tie (DSRA photo).

 

 

 

 

 

 

 

 

 

 

Underwater portions of a second marine railway that extends approximately 350 feet into the harbor from the Maritime Gloucester property were also recorded and documented. This second railway was built in 1853 for the Burnham Brothers Shipyard by the same Crandall Dry Dock Engineers of East Boston to service and repair vessels up to 1,000 tons, and is the oldest continuously operating marine railway in the country. Maritime Gloucester now uses the railway to repair wooden schooners and enhance its maritime educational programs.

DSRA reviewed underwater video of the submerged portions of the marine railway that were exposed in the harbor floor during the remediation project’s hand-dredging operations. Identified remains consist of the back-haul sheave assembly and its wood foundation, diagonal cross-bracing between the rails, and wood shims and wood caps between foundation piles and cross-ties where they connected to the undersides of the rails.

Cluster of closely-spaced foundation piles under the active marine railway (Steele and OceanEye’s 2017 post-dredge ROV video)

Two misplaced foundation piles (circled areas) located beyond the edges of one of the railway’s rails (Steele and OceanEye’s 2017 post-dredge ROV video)

 

 

 

 

 

 

 

Gaps between the active marine railway’s foundation piles and rails were filled with shim and caps (Steele and OceanEye’s 2017 post-dredge ROV video).

The active marine railway’s back-haul sheave that was completely exposed after hand-dredging by commercial divers (Steele and OceanEye’s 2017 post-dredge ROV video).

 

 

 

 

 

 

 

To learn more about the historic and archaeological resources studied as part of the Former Gloucester MGP Remediation Project, see

 

Public Archaeology Laboratory (PAL) – December 2016 

The Public Archaeology Laboratory, Inc. (PAL) is providing cultural resources services in support of the Remediation Project.  PAL’s work at the site was ongoing throughout 2016, and the following narrative and photographs provide a summary of their work completed to date to document the seawall removal, excavation, and reconstruction; and progress on the marine railways documentation and recordation.

Project contractors removed the historic granite wharf and adjacent soils in Solomon Jacobs Park during the fall of 2015 and winter of 2016. Excavations uncovered several components relating to historical gas manufacturing activities at the site. These consisted of large concrete footings, remnants of brick walls and foundations, and piping.

Below these more recent archaeological remains, the lower soils behind the wharf were composed of fill. Previous occupants of the site had dumped this material into the harbor as they “wharfed out” their property to create more usable land. Mixed into this fill were large amounts of granite rubble salvaged from Cape Anne’s many quarries, as well as isolated cultural artifacts such as shoes and broken bottles.

Solomon Jacobs Park and seawall at the beginning of remediation activities (PAL photo).

Solomon Jacobs Park and seawall at the beginning of remediation activities (PAL photo).

Concrete footings of the Former Gloucester MGP buildings in fill within Solomon Jacobs Park (Anchor QEA photo).

Concrete footings of the Former Gloucester MGP buildings in fill within Solomon Jacobs Park (Anchor QEA photo).

 

 

 

 

 

 

 

During excavation of impacted soils, contractors carefully removed and cleaned the seawall granite to save it for a new park seawall (PAL photo).

During excavation of impacted soils, contractors carefully removed and cleaned the seawall granite to save it for a new park seawall (PAL photo).

Solomon Jacobs Park seawall was removed during the winter of 2015–2016 (PAL photo).

Solomon Jacobs Park seawall was removed during the winter of 2015–2016 (PAL photo).

 

 

 

 

 

 

 

 

 

 

 

The Solomon Jacobs Park seawall was rebuilt in the winter and spring of 2016. The Project team designed and built a new wall that would be compatible with Gloucester Harbor’s historical character and meet stringent engineering requirements.

Employees of Custom Stone Builders lay out courses of the Solomon Jacobs Park seawall in the Remediation Support Area (PAL photo).

Employees of Custom Stone Builders lay out courses of the Solomon Jacobs Park seawall in the Remediation Support Area (PAL photo).

Careful handling and placement of stones while working “in the wet”.

Careful handling and placement of stones while working “in the wet”.

 

 

 

 

 

 

 

 

PAL made regular visits during seawall reconstruction for observation and recordation of the contractor’s work progress (PAL photo).

PAL made regular visits during seawall reconstruction for observation and recordation of the contractor’s work progress (PAL photo).

The seawall nears completion in the May 2015 (PAL photo).

The seawall nears completion in May 2016 (PAL photo).

 

 

 

 

 

 

 

Project contractors completed pre-dredge debris removal in the near shore areas of the historic marine railway structures in September 2016. The debris removal was performed by commercial divers assisted by a barge-based large machine-excavator that was used to lift items rigged by the divers out of the water and into a hopper barge. PAL’s marine archaeologist from DSRA inspected and recorded historic marine railway elements and other debris that were found by the divers lying on or extending above the surface of the inner harbor floor. Marine railway elements include pieces of wood railway timbers and iron. Included among the recovered wood elements are intact and fragmentary pieces of the inactive marine railway’s rails, cross-ties, and chocking-timber components of the inactive marine railway’s cradle. The iron pieces are fragments and intact sections of the inactive marine railway’s iron strapping with fasteners that were formerly attached to the top of the railway’s wooden rails.

Dredging work to remove contaminated sediments and portions of the inactive marine railway extending to the 2004 Gloucester Harbor Commissioner’s Line began in November 2016. PAL’s marine archaeologist will continue with the field monitoring and recordation work for any components of the historic marine railways that are encountered and removed from the harbor floor during dredging.

Overview of pre-dredging debris removal in the area of the historic (inactive) marine railway (DSRA photo).

Overview of pre-dredging debris removal in the area of the historic (inactive) marine railway (DSRA photo).

Debris removed from the underwater area of the inactive historic marine railway—pile of steel cable with complete marine rail timber in the foreground (DSRA photo).

Debris removed from the underwater area of the inactive historic marine railway—pile of steel cable with complete marine rail timber in the foreground (DSRA photo).

 

 

 

 

 

 

 

 

 

 

 

Profile view of a rail timber showing where preferential preservation of the wood reveals the locations, widths and spacing of the marine railway’s wooden cross-ties (DSRA photo).

Profile view of a rail timber showing where preferential preservation of the wood reveals the locations, widths and spacing of the marine railway’s wooden cross-ties (DSRA photo).

The ends of the inactive marine railway’s complete rail timbers terminate in nibbed flat scarf joints that were secured with iron fasteners (DSRA photo).

The ends of the inactive marine railway’s complete rail timbers terminate in nibbed flat scarf joints that were secured with iron fasteners (DSRA photo).

 

 

 

 

 

 

 

 

 

Cradle chocking timber recovered from the inactive marine railway (left image) (DSRA photo).

Cradle chocking timber recovered from the inactive marine railway (left image) (DSRA photo).

Composite cradle chocking timber recovered from the inactive marine railway (left image) and the same timber type seen in the base of a cradle chock on the active marine railway (right image) (DSRA photos).

The same timber type seen in the base of a cradle chock on the active marine railway (right image) (DSRA photo).

 

 

 

 

 

 

 

 

 

 

 

Fastener holes, remnant fasteners, and the impressions of the iron strapping left behind in residual corrosion on the upper surface of some of the rail timbers provides information on the iron strapping’s locations and dimensions (DSRA photo).

Fastener holes, remnant fasteners, and the impressions of the iron strapping left behind in residual corrosion on the upper surface of some of the rail timbers provides information on the iron strapping’s locations and dimensions (DSRA photo).

Iron strapping preserved on the upper surface of one of two complete rail timbers that was recovered during pre-dredging debris removal (DSRA photo).

Iron strapping preserved on the upper surface of one of two complete rail timbers that was recovered during pre-dredging debris removal (DSRA photo).