Pacific Ocean Division News

Army engineers remove World War II-era explosives from national historic landmark on a remote Alaskan island

USACE Alaska District
Published Aug. 31, 2022
The U.S. Army Corps of Engineers’ Alaska District and Range Support Center collaborated to remove unexploded ordnance from 337 acres of land in 2020 and 2021 at the Fort Glenn Formerly Used Defense Site on Umnak Island in Alaska. The environmental restoration project is the first in the state to be funded by the DoD Military Munitions Response Program. (U.S. Army Photo)

The U.S. Army Corps of Engineers’ Alaska District and Range Support Center collaborated to remove unexploded ordnance from 337 acres of land in 2020 and 2021 at the Fort Glenn Formerly Used Defense Site on Umnak Island in Alaska. The environmental restoration project is the first in the state to be funded by the DoD Military Munitions Response Program. (U.S. Army Photo)

A field crew for the U.S. Army Corps of Engineers placed recovered military munitions in trenches at the Fort Glenn Formerly Used Defense Site on Umnak Island in Alaska. Technicians used controlled explosions to safely dispose of the consolidated piles of ordnance. (U.S. Army Photo)

A field crew for the U.S. Army Corps of Engineers placed recovered military munitions in trenches at the Fort Glenn Formerly Used Defense Site on Umnak Island in Alaska. Technicians used controlled explosions to safely dispose of the consolidated piles of ordnance. (U.S. Army Photo)

To find unexploded ordnance from the Fort Glenn Formerly Used Defense Site, a field crew for the U.S. Army Corps of Engineers initially conducted methodical surface sweeps of the land on Umnak Island in Alaska. Workers then used hand tools to extract munitions from the soil for consolidation into piles that were safely destroyed. For larger objects that were too dangerous to remove by hand, the team conducted detonations in place before removing remnants and debris. (U.S. Army Photo)

To find unexploded ordnance from the Fort Glenn Formerly Used Defense Site, a field crew for the U.S. Army Corps of Engineers initially conducted methodical surface sweeps of the land on Umnak Island in Alaska. Workers then used hand tools to extract munitions from the soil for consolidation into piles that were safely destroyed. For larger objects that were too dangerous to remove by hand, the team conducted detonations in place before removing remnants and debris. (U.S. Army Photo)

As a crew for the U.S. Army Corps of Engineers worked to clear buried munitions from the Fort Glenn Formerly Used Defense Site on Umnak Island in the summer of 2020, it unexpectedly discovered a 500-pound bomb. The following year, the team returned to the project site in remote Alaska with a remote-controlled excavator to safely neutralize the explosive device along with three others of the same size. (U.S. Army Photo)

As a crew for the U.S. Army Corps of Engineers worked to clear buried munitions from the Fort Glenn Formerly Used Defense Site on Umnak Island in the summer of 2020, it unexpectedly discovered a 500-pound bomb. The following year, the team returned to the project site in remote Alaska with a remote-controlled excavator to safely neutralize the explosive device along with three others of the same size. (U.S. Army Photo)

In 2008, the eruption of Mount Okmok generated a volcanic mudflow that covered a 70-acre portion of the Fort Glenn Formerly Used Defense Site on Umnak Island in Alaska. A field crew for the U.S. Army Corps of Engineers found that this lahar layer varied in depth from a few inches to as much as 4 feet in some areas during the process of removing unexploded ordnance from the site in 2020 and 2021. This issue required the team to excavate wider and deeper to ensure all munitions were safely recovered from the soil. (U.S. Army Photo)

In 2008, the eruption of Mount Okmok generated a volcanic mudflow that covered a 70-acre portion of the Fort Glenn Formerly Used Defense Site on Umnak Island in Alaska. A field crew for the U.S. Army Corps of Engineers found that this lahar layer varied in depth from a few inches to as much as 4 feet in some areas during the process of removing unexploded ordnance from the site in 2020 and 2021. This issue required the team to excavate wider and deeper to ensure all munitions were safely recovered from the soil. (U.S. Army Photo)

Boom! Another explosion went off as a field crew for the U.S. Army Corps of Engineers – Alaska District worked to safely clear and detonate munitions remaining from the World War II-era Fort Glenn, an abandoned military installation in the Aleutian Islands 850 miles from Anchorage.

Under the Department of Defense’s Formerly Used Defense Sites Program, the team removed more than 2,200 items classified as either discarded ammunition or unexploded ordnance, while recovering 56,000 pounds of metallic debris at the remote outpost during summer field seasons in 2020 and 2021.

The successful completion of these remediation activities reduced risk to human health, while helping to protect and preserve the environment.

“By conducting this work, it is a much safer place than it was three years ago, and it will allow the land to be used for other things down the road,” said Jeremy Craner, project manager.

Fort Glenn was built in secret under the guise of the Blair Fish Packing Company in late 1941 and is the most recent site in the state where USACE has executed an environmental restoration project with funding from the DoD Military Munitions Response Program.

During World War II, the military used a portion of land on Umnak Island as a disposal site for munitions and explosives. Unfortunately, not all the ordnance was detonated, leaving an unstable and unsafe environment.

To address these concerns, the Alaska District partnered with the technical staff at the USACE Range Support Center in Sacramento, California, for assistance with contracting services and oversight of the fieldwork. Because of the hazardous nature of the remedial action, on-site personnel included munitions experts along with an ordnance and explosives safety specialist.

“The team consisted of specially trained technicians,” Craner said. “Almost everyone was former military and certified to find and remove these items.”

Besides tackling a daunting assignment that required extensive coordination to ensure a technically sound approach and adherence to project requirements, group members had to mesh as a functional team.

“The Range Support Center and the Alaska District worked jointly on a challenging military munitions response program project – our first remedial action project,” said James Lukasko, RSC technical team lead. “None of the project delivery team members knew each other beforehand, so the roles and responsibilities needed to be decided, and because this was a joint effort, we had a great working relationship.”

Once on the ground, it was time to put months of planning and preparation into action. To locate the potentially dangerous, wartime remnants during the excavation process, the crew performed a methodical inspection of the surface area and underlying soil using planning grids and geophysical instruments.

With the help of a shielded excavator, workers removed most of the buried munitions by hand with a shovel or trowel. Once grouped into large trenches for disposal, the crew members destroyed the recovered items with controlled explosions. If they detected an object that was too dangerous to move, the team eliminated the threat at the spot where it was found. In total, technicians safely executed six consolidated detonations and 125 blow-in-place events.

To reduce costs and improve efficiencies, the crew employed two mobile soil screening plants. This approach decreased the volume of soil manually inspected by technicians and streamlined the process for segregating cleared soil.   

Based on earlier investigations of the property, the workers were prepared to extract a large volume of unexploded ordnance from the area. Projectiles, rockets, grenades, land mines and other types of munitions were known to be present in the soil. However, they did not anticipate finding a 500-pound bomb – let alone more than one. Eventually, the team uncovered four of the huge explosive devices along with 24 smaller bombs that weighed 20 pounds each.

“That really changed gears,” Craner said. “We had to quickly come up with a new plan to execute the work. We coordinated with the contractors, who gave us multiple alternatives, and then picked the best path forward for both executing the work and ensuring the safety of the team.”

The field crew decided to focus its efforts on other portions of the site until the appropriate equipment could be brought in to deal with the bomb the following year. At the time, workers were aware of just one. However, three more were revealed during the next field season.

“They did what they could in 2020 to demobilize and then went out in 2021 with a remote-controlled excavator to operate in the bomb craters and safely work through those areas,” Craner said.

The robotic vehicle allowed the crew to neutralize the massive bombs from a secure distance. Much like a video game, the equipment operator sat in a trailer outside the blast radius and monitored camera footage from the scene to safely maneuver the remote-controlled excavator into position and detonate the objects.

The unexpected discovery of enormous bombs was not the only obstacle that the team had to overcome. Crew members also needed to remediate 70 acres of land that was covered by a volcanic mudflow during the eruption of Okmok Volcano on Mount Okmok in 2008. The lahar buried munitions at depths ranging from a few inches to more than 4 feet.

In 2021, the team expanded the excavation zone to encompass the land coated by the volcanic layer. Once cleared of explosives, sites were backfilled with clean, native soil.

Executing environmental cleanup activities in the far-flung Aleutian Islands is difficult during normal times, but the challenges were magnified by the COVID-19 pandemic. The first field season was in jeopardy of postponement because of uncertainty about health protection protocols and potential travel restrictions. However, the team quickly responded to the situation by developing mitigation plans, adapting to the new operating environment and finding ways to keep the project moving forward. Collaboration with industry partners, communities and regulators was a critical factor in accomplishing the mission.

Yet the greatest hurdles facing the crew revolved around the impact of the project site’s location and climate on the delivery of vital logistical support. Sandwiched between the Bering Sea and Pacific Ocean in the Eastern Aleutian Islands, Umnak Island is only accessible by boat or aircraft.

“The remoteness of the site was unique,” said Cheryl Webster, RSC geophysicist. “The logistics needed to work at the site was different than I had experienced working at sites in the continental United States.”

During the war, Fort Glenn served as an Army airfield and defense garrison. Its mission was to provide air protection to the naval base 50 miles to the southwest at Dutch Harbor on Unalaska Island. The installation originally consisted of four airstrips; one had been maintained into the 1980s by a local airway, so the team was able to use it to land planes that brought people, supplies and food. Meanwhile, large equipment and oversized items were transported by barge. The vast travel distance to the island by air and water emphasized the importance of sound communication, coordination and logistical planning to minimize setbacks to the project. 

According to Lukasko, the region’s extreme and unpredictable weather generated additional hardships that some members of the team had not encountered on previous job sites.

In this isolated area, weather conditions can be quite localized and change rapidly. Fog, low cloud ceilings, precipitation, high winds, and clear skies are all possible at the same time within a few miles of each other. Severe storms may arise with little warning.

“Inclement weather was a constant challenge that delayed fieldwork and resupply flights, and fatigued personnel,” Craner said.

Adding to the unusual aspects of working in Alaska, the crew was forced to evacuate to higher ground during the night because of an earthquake and subsequent tsunami alert. The experience reinforced the need to be flexible and adaptable at all times while on the island.

Despite contending with tremendous adversity on the project, workers can take pride in making a lasting contribution that benefits both the planet and future generations. Reflecting on the magnitude of the task and quality of the work accomplished, Craner was particularly impressed with how so many professionals from different fields united to achieve a common goal.   

“It is a challenge to put together a team for something that you could not do by yourself,” he said. “It takes a lot of support from people across USACE and the contractor, so it is rewarding to see the work done and that things become better than they were before we started the project. The contractors have to figure out all the difficult details of how to execute the work, so they are the real heroes of our success, and without them nothing would get done.”

After five years, USACE officials will return to the island conduct an assessment and ensure the remediation efforts are effective.

Thought to be one of the most intact World War II-era military installation in the Aleutians, the National Park Service nominated the site as a national historic landmark in 1986; it was designated as such by the Keeper of the National Register of Historic Places in 1987.

“In late 1941, then-Maj. Benjamin Talley and Maj. Everett Davis of the U.S. Army Corps of Engineers led reconnaissance surveys in the vicinity of the naval base at Dutch Harbor in an effort to identify possible locations for supporting air bases,” said Kelly Eldridge, district archeologist. “Upon their recommendation, the War Department authorized an airfield to be constructed on Umnak Island in December 1941.”

The construction of Fort Glenn came just in time; fighters scrambling out of Fort Glenn were able to react when the Japanese bombed Dutch Harbor in early June 1942. The installation served as the headquarters for the 11th Air Force from July to September 1942, and at its height of activity, on April 8, 1942, it reached a maximum strength of 12,898 personnel.

After placing the base into caretaker status in 1945, the military closed the installation in 1950.

Today, the project site is located on property managed by the Alaska Department of Transportation and Public Facilities. Despite its remote location, harsh weather and rugged terrain, the land now hosts a working cattle ranch.

So not only is Fort Glenn a prominent historical site, it is now a much safer for people – and cows – to enjoy.

The Alaska District oversees the largest Formerly Used Defense Sites Program in the country with more than 500 sites identified for remediation in the state. The agency is committed to reducing risk, while protecting human health and the environment through these efforts.