On December 7, 1941, the Japanese attack on the US Navy base at Pearl Harbor, island of Oahu, Hawaii (plus Kaneohe Airbase, eastern shore, and the inland Wheeler Army Airfield near Schofield Barracks), resulted in the official entry of the United States into World War II. The event is annually commemorated in several US cities, most notably at the USS Arizona Memorial in Pearl Harbor. In 2016, with survivors of the attack at least in their 90’s, the Pearl Harbor events on the 75th anniversary may have been the last major gathering of military personnel present during the devastating raid. As of September 2019, only three survivors were still alive; according to CNN, but only one of them attended 2019 ceremonies at the memorial. However, one of those three died in February 2020. [Update: the last USS Arizona survivor, Lou Conter, died on April 1, 2024; a June 2023 interview with Conter is here.] This year (2020), the National Park Service and the Navy has closed the ceremony to the public, including Pearl Harbor survivors, due to the coronavirus.
Like the Vietnam Veterans’ Memorial in Washington, DC, the Arizona Memorial is enveloped in intense solemnity and a bubble of consensual and imposing silence, awe, and reverence, despite the surrounding boat traffic. “The wrecked Arizona” is “a crystallized moment in time, its death wounds visible and still bleeding oil, the intact hull holding most of the crew.” The leaking oil is estimated at 2-9 quarts per day . The major “oil release” points identified in the 1980’s are two hatches, but since then the estimate volume of oil leaked has increased as the number of identified and monitored leakage points has risen. Volume also varies with weather and tides. The oil has been called the ship’s blood or the “black tears of the Arizona”; legend says the leak will end when the last surviving Arizona crewmember dies.
The Arizona Memorial, as we know it today, was dedicated in 1962. The Memorial building sits over, but does not touch, the battleship USS Arizona, sunk in the Pearl Harbor attack, and the resting place of 1,102 of the 1,177 crew members killed, about half of all the fatalities from the raid. In the 1950’s, before the current memorial, a flag was raised and lowered at the site daily; to this day, personnel of passing US military ships “man the rails”, salute and honor the Memorial and sacrifice of those killed in the 1941 attack. The Memorial itself is on the National Register of Historic Places”. The wreck (ship) is a National Historic Landmark and an active military cemetery.
In addition to crewmembers entombed during the attack, 44 survivors of the attack have been interred on the Arizona. The information about internment and the list of those buried there are at https://www.nps.gov/valr/learn/historyculture/ussarizonainterments.htm . There are links from some names to photos, articles or videos of the internments. In 2019, FC2c Lauren F. Bruner (https://www.youtube.com/watch?v=Ko0QBUqs1BE) was the final crewmember interred on the Arizona since the remaining survivors have chosen to be buried elsewhere. A re-enactment of such a burial is also at the end of NCIS episode “The Arizona”, Season 17, episode 20, April 2020.
The USS Arizona (BB-39) is a Pennsylvania-class battleship (“super-dreadnought”, decommissioned now) launched in 1915. At the time, it was the largest battleship built. It was 608 feet long with four triple-gun turrets. Exterior armor thickness in 1941 ranged from 8-13.5 inches (20-34 cm), bulkheads 8-13 inches. Deck armor was 4-8 inches (10-20 cm). A modernization in 1931 replaced, among other things, the original masts with “new tripod masts, surmounted by three-tiered fire-control directors”. A detailed structural description and timeline of the Arizona, as originally built plus subsequent upgrades, can be found in the 2012 maritime history and archaeology Masters’ thesis by Valerie Rissel at East Carolina University.
Rissel also explains the significance of Arizona as one of the first oil-fueled battleships in 1915, rather than being a traditional coal-burning vessel. Using fuel oil extended the time between refueling since, for the same volume of fuel, oil produces more units of energy (i.e. BTUs or joules) and requires less maintenance crew, therefore, cheaper overall. However, this limited the ship’s utility in World War I since many strategic European ports did not stock oil.
The Arizona used Bunker C (#6) fuel oil. As Nuroil describes it: “Number 6 fuel oil is a high-viscosity residual oil requiring preheating to 220–260 °F (104–127 °C). Residual means the material remaining after the more valuable cuts of crude oil have boiled off. The residue may contain various undesirable impurities including 2 percent water and one-half percent mineral soil.”
The Arizona was assigned to the Pacific fleet in 1921 and based out of Hawaii starting in 1940. After a “night-firing exercise” with the Nevada and Oklahoma on December 4, the Arizona was moored in “Battleship Row” on the east side of Ford Island; on December 6, the repair ship Vestal arrived alongside, docked, and was tethered to the Arizona (Figure 8). On the same day, the battleship was refueled with a final supply of 1.2-1.5 million gallons of fuel oil (estimates vary). The oil was stored in 200 bunkers (tanks) on four decks. The Arizona also had on board aviation fuel plus powder for 14-inch guns.
On Sunday, December 7, 1941, “Japanese aircraft appeared in the air over Pearl Harbor just before 8:00 am . . .The color detail was on deck in anticipation of raising the flag at the stern at 8:00. The Arizona came under attack almost immediately, and at about 8:10 received a hit by an 800-kilogram bomb just forward of turret two on the starboard side” and about 40 feet from the bow. “Within a few seconds, the forward powder magazines exploded, gutting the forward part of the ship. The foremast and forward superstructure collapsed forward into the void created by the explosion and turrets one and two, deprived of support, dropped more than 20 feet relative to their normal position. The explosion ignited furious fires in the forward part of the ship. The majority of the crewmembers were either killed by the explosion and fire or were trapped by the rapid sinking of the ship.” The fires burned for 2 1/2 days. Description of the attack (4 minute video) with actual footage and borrowed clips from the movie "Pearl Harbor": https://www.youtube.com/watch?v=F6Ttfri8H6Q
The Arizona settled nearly upright. It is currently partially buried in about 25 feet (8 m) of harbor sediment (Rissel, p. 34) in ca. 38 feet (12 m) of water. The draft of the Arizona was just under 29 feet (Rissel), so the water/sediment line now is about at the ship’s original waterline. The overhead view of the Memorial and wreck (Figure 3) shows the visible bow is separated by a gap from the rest of the ship, the gap being the location of the collapsed and exploded forward magazines. The stern of the ship sits on soft clay while the bow is underlain by stiff clay with coral debris. “The sunken vessel provides substrate for many encrusting filter-feeding organisms such as sponges, bryozoans, annelid worms, mollusks, and tunicates as well as filamentous diatoms, and green and red algae. These organisms (both live and dead) comprise over 99% of the cover of all vertical surface area (Henderson, 1986", cited in Daniel, 2006, below).
It is estimated that 1/3 of the fuel on board the Arizona burned in the fires, 1/3 was released uncombusted into the harbor, and 1/3 (500,000-600,000 gallons, 11,900-14,300 barrels or ~2 million liters) remained on board. As mentioned earlier, the estimates of current leakage rate range from 2-9 quarts per day (1.9-8.5 liters): at a high average rate of 7 qts/day, I calculated about 50,000 gals (~1200 barrels; 190,000 liters) would have leaked, post attack, since 1941. Compared to the general range of estimated remaining oil, my calculated loss is relatively insignificant and doesn’t really diminish the estimated onboard load.
The large amount of oil remaining on the Arizona, coupled with the corrosion of the wreck, has raised concerns about a sudden catastrophic release of oil. The Arizona National Historic Landmark is cooperatively administered by the National Park Service and the Navy. An initial 1983-84 study (Lenihan, 1990, citation and link below; 1991 blog post by Lenihan describing diving on the Arizona) was the first undertaken to determine exactly what was still present and the condition of the ship. Most of the superstructure and armaments were removed during salvage through 1943, but the Lenihan study discovered that the No. 1 turret 14-inch guns were still in place, in addition to a number of live shells, which were removed. Although helmeted, tethered divers were used to salvage materials from inside the ship in the immediate aftermath of the attack, currently neither human divers nor remote robot investigations cannot, or do not, venture many places inside the ship due to both concern about wreck integrity and out of respect for the dead entombed there. Rissel’s Master’s thesis (2012, link below) summarizes the contrasting issues of environmental protection and resting-place respect.
“Many scientists have addressed the problems of metal corrosion but rarely with the variables encountered at Pearl Harbor: an immense steel object with water on both sides of the plates, existing in an environment rich in biological organisms and full of stray currents from many possible sources. The water was presumably aerobic on the hull's exterior but the oxygen content of water in the interior was unknown” (Lenihan, p. 9). The goals of that study were collecting data and describing the environmental conditions of the wreck site, and, probably the most important contribution, a description and drawings of the wreck below the water.
Building on this initial documentation, since 1998, investigations of the USS Arizona Preservation Project have focused on the structural integrity (metal degradation) of the Arizona and the contained oil. The onsite studies have value not just for understanding degradation of that ship but of how other liquid-fuel-bearing wrecks in US waters may also corrode. A list of several studies by year are included at the end of this post. These include those by scientists and engineers from the National Park Service’s (NPS) Submerged Resources Center; National Institute of Standards and Technology; University of Nebraska; the Rissel thesis; a study of the organic geochemistry of and microbes digesting the leaked oil (Graham, 2003). US Geological Survey studies include instrumentation installed to measure water currents around the wreck, and investigation of sediment type on which the wreck sits and resultant settling rate. Oil studies at Woods Hole Oceanographic Institution and by US Coast Guard cadets are ongoing.
From metal corrosion studies, estimates of time until hull collapse and possible catastrophic release of oil have ranged from 10-20 years (Foecke et al., 2010, citation below) to 150-200 years (Johnson et al., 2018). The National Park Service currently estimates 100-150 years. Organic geochemistry of oil from the Arizona indicates that some leaked oil is degraded suggesting it had leaked from its original storage bunker and pooled somewhere else in the ship before release to the harbor (Graham in Murphy, 2008, p. 371-372).
In contrast, it is interesting to note that a study of the deterioration of coal from the Titanic (sank April 1912) showed it had little chemical alteration and, therefore, minimal environmental impact due to interaction with the seawater, compared to widespread environmental damage effects of oil spills. However, in limited surface and stream drainages, the weathering of coal, specifically of iron sulfides like pyrite in the coal, can produce damaging acid mine drainage.
A two-and-a-half minute underwater video tour of Arizona by National Geographic can be found at https://www.youtube.com/watch?v=8zVV7AX-lfQ .
*Selected articles and reports on USS Arizona metal corrosion, wreck environment, and contained oil, in chronological order:
1990: Lenihan, Daniel (editor), Submerged Cultural Resources Study: USS Arizona Memorial and Pearl Harbor National Historic Landmark: Submerged Cultural Resources Unit, National Park Service, Submerged Cultural Resources Center Professional Papers No. 23 (First edition, 1989; second edition, 1990). Link to complete Table of Contents, with chapter links, at https://www.nps.gov/parkhistory/online_books/usar/scrs/scrst.htm; links to scanned pdfs of original report https://www.nps.gov/orgs/1635/upload/USAR_017_D6A_-34619.pdf and https://ia800606.us.archive.org/4/items/submergedcultura01ussa/submergedcultura01ussa.pdf .
1991 Lenihan, Daniel: The Arizona revisited: Divers explore the legacy of Pearl Harbor. https://www.naturalhistorymag.com/htmlsite/master.html?https://www.naturalhistorymag.com/htmlsite/editors_pick/1991_11_pick.html
2003 Russell, M.A., and Murphy, L.E., Long-Term Management Strategies for the USS Arizona: A Submerged Cultural Resource in Pearl Harbor, Hawaii: National Park Service, Submerged Resources Center and USS Arizona Memorial Legacy Resources Management Fund Project No. 03-170, 2003 Annual Report Technical Report 15, 21 pages. https://www.denix.osd.mil/cr/archives/archaeology/archaeology-underwater-archaeology-archives/2003-report/27_USS%20Arizona%20Memorial%20-%202003%20Annual%20Report%20(PDF),%20Report%20(Legacy%2003-170).PDF The report summarizes the methods of various investigative projects and goals, most results of which are in subsequent publications listed below.
2003 Graham, Amanda, The USS Arizona and Bunker C Fuel Oil: An Environmental Study, Master’s thesis, Medical University of South Carolina (MUSC). A 91-page report by Graham (the entire thesis?) is included in the 2008 report below, p. 295-386.
2006 Daniel, R., Appendix A: USS Arizona Memorial resource overview. In: HaySmith, L., F. L. Klasner, S. H. Stephens, and G. H. Dicus. Pacific Island Network vital signs monitoring plan. Natural Resource Report NPS/PACN/NRR—2006/003 National Park Service, Fort Collins, Colorado. https://irma.nps.gov/DataStore/DownloadFile/575315
2006 Russell, M.A., Conlin, D. L., Murphy, L.E., Johnson, D.L., Wilson, B.M., Carr, J.D., A minimum-impact method for measuring corrosion rate of steel-hulled shipwrecks in seawater: The International Journal of Nautical Archaeology, v. 35, p. 310-318. https://core.ac.uk/download/pdf/188135446.pdf Nice photos of metal disk samples of Arizona hull; cross-section of ship and plan views of wreck.
2006 Johnson, D.L., Wilson, B.M., Carr, J.D., Russell, M.A., Murphy, L.E., Conlin, D. L., Corrosion of steel shipwreck in the marine environment: USS Arizona: Materials Selection and Design. Part I- October 2006, p. 40-44 (https://digitalcommons.unl.edu/chemfacpub/192/ ); Part II- November 2006, p. 54-57 (https://digitalcommons.unl.edu/chemfacpub/191/ ).
2008 Murphy, L.E., and Russell, M.A., Long-term management strategies for USS Arizona, a submerged cultural resource in Pearl Harbor: National Park Service Submerged Resources Center Technical Report Number 27, 513 pages. https://www.history.navy.mil/content/dam/nhhc/research/underwater-archaeology/PDF/UA_ManagementUSS Arizona.pdf
2009 McNamara, C.J., Lee, K.B., Russell, M.A., Murphy, L.E., Mitchell, R., Analysis of bacterial community composition in concretions formed on the USS Arizona, Pearl Harbor, HI: Journal of Cultural Heritage, v. 10, p. 232-236. https://doi.org/10.1016/j.culher.2008.07.010
2010 Foecke, T., Ma, L., Russell, M.A.., Conlin, D.L. Murphy, L.E., Investigating archaeological site formation processes on the battleship USS Arizona using finite element analysis: Journal of Archeological Science, v. 37, p. 1090-1101. https://doi.org/10.1016/j.jas.2009.12.009
2012: Rissel, Valerie, The Weeping Monument: A pre and post depositional site formation study of the USS Arizona: Master’s Thesis, East Carolina University, 127 pages. http://thescholarship.ecu.edu/bitstream/handle/10342/3841/Rissel_ecu_0600M_10669.pdf?sequence=1 or https://pdfs.semanticscholar.org/e7b1/dd8d6ca6ba7146d5ea61b9ecff9d05ed86a8.pdf
2013: Carkin, B.A., and Kayen, R.E., Settlement of the USS Arizona, Pearl Harbor, Hawaii: US Geological Survey Scientific Investigations Report 2013-5096, 154 pages. https://pubs.usgs.gov/sir/2013/5096/pdf/sir2013-5096_text.pdf
2018 Johnson, D.L., DeAngelis, R.J., Medlin, D.J., Johnson, J.E., Carr, J.D., and Conlin, D.L., The secant rate of corrosion: correlating observations of the USS Arizona submerged in Pearl Harbor: The Journal of The Mineral, Metals & Materials Society (TMS), vol. 70, p. 747-752. https://www.researchgate.net/publication/323531809_The_Secant_Rate_of_Corrosion_Correlating_Observations_of_the_USS_Arizona_Submerged_in_Pearl_Harbor/link/5b5f3d160f7e9bc79a6f4712/download
2018 US Coast Guard, Cadets study the Tears of the Arizona: The Maritime Executive, (9-21-2018); https://www.maritime-executive.com/editorials/cadets-study-the-tears-of-the-arizona
