Okinawa Defense Bureau's Report on Okinawa City Soccer Field Raises Questions

On February 10, 2015, the Okinawa Defense Bureau (OBD) released a new report on its investigation of the Okinawa city soccer field.  The ODB’s report was then delivered to the other side of the fence—it was used by Kadena Air Base (KAB) to declare its community’s safety. Three experts argue however that the Bureau’s report downplayed the results of the investigation on the “stagnant water” in the ground, and suggested that ODB should carry out further analysis and investigation. 

Background
In June 2013, 26 barrels –some marked Dow Chemical—were discovered at the Okinawa City’s soccer field, former US Base site. Following the discovery, Okinawa Defense Bureau (ODB), Okinawa Prefectural Government (OPG) and Okinawa City began their investigations into the barrels and surrounding soil.  As of today, more than one hundred barrels have been discovered there and further investigations have been conducted.  

The series of investigations undertaken so far can be broken down into three rounds. The first round of investigation started in June 2013 and they focused on the 26 barrels. A report was issued by the OBD in July 2013, revealing that the barrels were highly contaminated by dioxins. 

The Second round of investigation took place in October 2013 when the OBD, under pressure from Okinawa City Assembly, NGOs, and Okinawan people, conducted a full-scale investigation of the soccer field. It included magnetic survey and interview with local people. The number of the barrels unearthed by then amounted to 83. Okinawa City cross-checked (cross-examined) the ODB’s investigation and concluded that the contamination of the succor field need to be understood as “multiple contamination” with substances including dioxins, PCP, PCB, arsenic, fluorine and so forth. Three experts stated that it is highly likely that, in the past, “herbicides containing components of defoliants” were present in the soccer fields. 

The Third Round of Investigation

The third round of investigation, started in October 2014, stepped into a new direction. Until the second round, the main focus of investigations was on analysis of the contamination of the residues in these barrels and surrounding soil. In the third round, the focus was on determining the extent of dioxin contamination. To do so, OBD investigated and analyzed underground stagnant water sampled last October from four sites near where those 83 barrels were unearthed. The underground stagnant water was considered to have been oozed out of the soil in which the barrels were buried and to have “stagnated” in soil pore spaces in those sites.

Okinawa Defense Bureau sampling the stagnant water（source: Report of Okinawa Defense Bureau)

On Februray 10, ODB released a report on the analysis on the stagnant water and concluded that the extent of contamination was limited. 

Experts’ comments on Okinawa Defense Bureau’s report
To cross-examine ODB’s investigation and report on the stagnant water, the Citizens’ Network for Biodiversity in Okinawa (Okinawa BD) contacted and asked three experts to review and give comments on the OBD report. All the three experts argued that ODB downplayed the result of the investigation and the extent of dioxin contamination. On March 12, Okinawa BD held a press conference and released the experts’ comments. Okinawa BD also sent copies of the comments to the Okinawa Defense Bureau and four related administration offices, requesting them to review and discuss these experts’ comments. 

Summaries of the experts’ comments are as follows. 

1. Dr. Miyata Hideaki, a prominent expert on dioxin, analyzed the ODB’s report: he focused on data regarding dioxins present in the stagnant water. 

Dr. Miyata pointed out the stagnant water was highly contaminated with dioxins. 170pg-TEQ/L of dioxin was detected in the unfiltered stagnant water (170 times higher than the standard value set forth in the water quality environmental standards) , and 33pg-TEQ/L of dioxin in the filtered water (33 times higher than the value set up in the water quality environmental standards). 
 Dr. Miyata also indicated that these dioxins were present in dissolved form, not in particulate form. Implications are, according him, that highly concentrated dioxins should have been continuously eluted from the barrels through rainwater into the soil for a long period of time.  The ODB’s report does not mention nor does it assess the possibilities of elusion of dioxins from the barrels.  

Additionally, Dr. Miyata pointed out several invalidities in ODB's report, including their isomer specific analysis on dioxins. It indicates that ODB’s report has failed to undertake accurate assessment of the source of contamination. 

 2. Ms. Komichi Ikeda, a Japanese expert on dioxin contamination, argued that ODB and Okinawa Prefectural Government should have paid serious attention to the very fact that dioxins were detected in the discharged water sampled from a drainage ditch in the soccer field area.  She stated that even though 3 pg TEQ/L of dioxins in the discharged water was below the environmental standards for drainage water (, which is 10pg TEQ/L), ODB should have addressed this issue carefully. This is because those dioxins were detected at the soccer field, where children played/would play, not at industrial factories and hazard waste facilities. 

Ms. Ikeda also emphasized that 15% of the dioxin isomers detected in the stagnant water was 2,3,7,8-TCDD, the most toxic dioxin, and this percentage value is not low, and warned that ODB and OPG should not underestimate this result.

 In addition, she pointed out that ODB failed to identify the sources of the dioxin contamination in the discharged water. In its report, ODB analyzed the chronological data regarding dioxins detected in the discharged water from the drainage ditch and acknowledged that the presence of dioxins in the discharged water was due to the ODB’s excavation of the barrels, which took place from the end of January to early February in 2014.  While it can be referred that the excavation of the barrels had transferred dioxins to the drainage ditch, ODB did not discuss the sources of the dioxin contamination in the discharged water and nor did it examine possible pathways through which those dioxins had been transferred to the discharged water.  

Ms. Ikeda and Dr. Miyata (in his email to us) stated that it would be the next step of investigation to ascertain why those dioxins were presented in the discharged water. 
         
3. Dr. Shingi Kuniyoshi, a geologist who worked on the environmental cleanup program at the March Air Reserve Base, California, questioned ODB’ assessment that the extent of contamination through ground water is limited and reasoning that the top silt clay layer in which the barrels were fund and the clay layer immediately below are both impermeable and thus that there was little possibility of the ground water containing dioxins moving downward and spreading in the layers. 

 Dr. Kuniyoshi pointed out that since silt clay is not completely impermeable, the ground water moves through the silt clay layer downward though slowly until it hit the clay layer; once the water hit the clay layer, it would move horizontally until it reaches the edge (end) of the clay layer and moves downward to the next layer below. Therefore, Dr. Kuniyoshi argued that Okinawa Defense Bureau should determine and explain the extent of contamination through ground water by using maps of the ground water supply and the Kadena aquifer.   




Problems of Kadena Air Base’s Announcement to its Community 
Following the ODB’s February report, the Kadena Air Base (KAB) issued an announcement to assure its community that “Kadena, ODB, OPG experts continue to agree there is no health risk to the local population from the excavation site; our children are safe.” 
here. 

Okinawa BD however has to say again, as we did it in our October 2014 letter to KAB, that KAB should provide accurate, sufficient and transparent information to its community. 
For reference: “Letter to Kadena Air Base from Okinawa environmental NGO” (blog article on Okinawa Outreach, October 11, 2014)

This time, we have found the following problems with KAB‘s announcement: 

1.Kadena Air Base provides little information regarding details of ODB’s investigation on stagnant water. 

As KAB failed to include in its announcement important primary data of ODB’s report regarding the stagnant water, the KAB community has not been informed that the stagnant water sampled from the soccer field was highly contaminated with dioxins. Omission of such important information could mislead the KAB community either to have a false sense of safety or to have doubt about the credibility of KAB announcement. KAB should provide its community ODB’s primary data as well. 

2. Kadena Air Base provide little information regarding details of its own investigation on air samples.

 Regarding KAB’s own investigation on air samples, KAB wrote that “the samples shown that there is no migration of substances from the soccer field excavation site through the air.” KAB failed to provide any primary data or analysis to support this claim. Nor did it mention what these “substances” were. Omission of such information deprives the KAB’s community and us of chances to check whether the KAB’s investigation was conducted adequately/properly and whether their analysis was accurate. We believe the KAB community should request KAB to release its official report for reviewing their investigation. 

3. KAB’s description of its coordination with ODB and OPG is inaccurate. 

 In its announcement, KAB describe the coordination with ODB and OPG as saying “Kadena health and environmental experts continue to discuss these results to ensure mutual understanding of each report”. However, according to the Okinawa Prefectural Government, KAB did not hold a meeting to discuss these results as they had done after when the report of the second round investigation was issued. This description is thus misleading. 
  


In addition to these problems of the KAB’s announcement, we are concerned that there are no “dust nets” set up on the side of the excavation site facing Bob Hope Primary School and Amelia Earhart Intermediate School. On the other side of the excavation facing the road  upon Okinawa City’s request, Okinawa Defense Bureau set up “dust nets” to prevent airborne dust from escaping to outside the excavation site.  We are wondering if nets are need or not. KAB should discuss this issue with ODB and explain to its community.  





VOCs detected in Other Barrels 
On March 23, 2015, ODB released an interim report regarding its on-going investigation on 17 barrels, which were unearthed in February 2015. The report indicated that volatile organic compounds (VOCs), including tetrachloroethylene（PCE） and Trichloroethylene (TCE), were detected from some of the barrels . 
Noticeably, in one sample of the residues from the barrels, 9100 mg/L of dichloromethane (http://www.cdc.gov/niosh/ipcsneng/neng0058.html) was detected, exceeding 46,000 times the environmental standards set forth in the Soil Contamination Countermeasures Law. We will upload an article discussing the OBD’s interim report on VOCs. 


Dr. Masami Kawamura
Director/Co-Representative 
Citizens’ Network for Biodiversity in Okinawa