Tuesday, August 14, 2012

Encanto Park and Radioactive Tritium

Majia here: I've posted previously about the work of Capt. Clyde Stagner, Retired. 

He spent much of his professional life monitoring radiation readings for government agencies. I will post links to his book, Hidden Trituim and my previous discussions of his work at the bottom of this post. 

Tritium is essentially a radioactive isotope of hydrogen that emits beta particles as it decays. Its high energy beta particles can cause damage to human DNA.

Harrison and Day describe the biological effects of tritium in their article “Radiation Doses and Risks from Internal Emitters”:

[Excerpted] "low energy beta emissions from tritium (3H) decay have been shown to have RBE (ratio of the absorbed dose) values of up to between 2 and 3 (compared to gammay rays), for in vitro end-points including cell killing, mutation and induction of chromosomal aberrations.[x]

Tritium is released by nuclear power plants, routinely (see http://www.msnbc.msn.com/id/43475479/ns/us_news-environment/t/radioactive-tritium-leaks-found-us-nuke-sites/#.UAZNT6N0jwk). 

The Palo Verde nuclear power plant is located in the far west of the Phoenix metropolitan area. The wind typically blows from the west to the east, bringing tritium with it.  

Capt Stagner is petitioning the NRC to resume tritium monitoring in Maricopa County air.
Monitoring of tritium in the air ceased several years ago, in 2010, after consecutive years of annual increases in tritium detections.

Capt Stagner's data suggest that open water in the county, especially smaller bodies of water, such as lakes and swimming pools, may have become contaminated with tritium. 

Radiologically contaminated water poses dangers to those who swim in it, eat fish living in it, and accidentally swallow it.

Below you will find a letter sent by Capt. Stagner to the Director of the City of Phoenix Parks about the radioactive tritium contaminating water sources in Maricopa County, including the lake at Encanto Park.  
People eating fish from this lake or others may be consuming contaminated fish. Testing should be resumed and extended to evaluate the impact of tritium on local waters.

Also below find the NRC email stating that the petition to resume tritium monitoring in Phoenix will be reviewed.


Director
Phoenix Park and Recreation Department,
200 W. Washington St #16,
Phoenix,AZ  2003
                                                                                   
Subject: Encanto Lake

Dear Sir,

Encanto Lake was in existance before 1985 when the EPA, with ARRA assistance, began radioactive tritium precipitation monitoring at the Phoenix monitoring station. Yearly monitoring sampling continued through 2010, after which only two samples were taken in early 2011.

No reason for cessation of the tritium precipitation monitoring in Phoenix has been ascertained.

[Prior] Results of the Phoenix tritium precipitation monitoring are available to the public at the EPA RADNET ENVIROFACTS DATABASE on the internet.

The Phoenix monitoring station collected and published an annual tritium average from 1985 until 1995 when the measurement of tritium in rainfall protocol change to instrumentation using LLD and MDC ranges of solution.

Consequently,an annual tritium concentration from 1985 through 1994 and an annual rainfall average for Phoenix were used to calculate the average annual tritium concentration from 1995 through 2010.

Prevailing winds are from the west during eleven months of each year.

In 2005, a second Phoenix monitoring station,Phoenix/956 became operational by the EPA.


Monitoring identical radioactive isotopes at both locations resulted in concentrations at the Phoenix station being 82.5 per cent of those measured at Phoenix/956.

The annual average used for the Encanto Lake was determined by an adjustment to the concentration of the annual tritium concentration at the Phoenix site due to the Encanto Lake proximity to Phoenix/956.

Encanto Lake has a surface area of 11,700 sq.ft. with an average depth of 8 ft  for a pool volume of 9,3850.3 ft^3 = 26.57840 x 10^5 Liters. The 1985 Phoenix Rainfall was 6.62 inches = 0.5572 ft. The precipitation volume was 11,700 sq. ft. x 0.552 ft = 6458 ft^3 = 182902 Liters.

The following is an example of determining  the Phoenix Encanto Lake tritium concentration  from the EPA Phoenix annual tritium rainfall concentration of 157 pCi/L:
           1.84618 L x 10^5 x 157pCi/L = 289.9 x 10^5 pCi which is evenly distributed in the total volume of the Lake plus the volume of the rainfall:

           26.57840 x 10^5 L + 1.82902 x 10^5 L = 28.426 x 10^5 L

and     (289.9 x 10^5 pCi ) /  (28.426 x 10^5 L) = 10.198  pCi/L

For reasons to be explained later, the residual concentration quantity remaining after nine years is determined by the exponential decay equation to be 5.79 pCi/l.

Similarly, the concentrations of each year 1986,1987,1988,1989,1990,1991,1992,1993,and 19904 are calculated and their residual concentrations in 5.79,3.139,0.483,7.716,67.04,6.877,10.27, 14.41,15.21, and 9.779 pCi/L respectively for a 1994 total tritium concentration of 126.8 pCi/L  in Ecanto Lake.
                                                                   
Circa 1995, the EPA replaced its tritium counting instrumentation with a protocol that places low counting unknown concentration results within a range involving an LLD or a an MDC, which resembles an antithesis to ALARA or censoring of existent specific low radiation concentrations necessary for radiation accumulation assessments.

The IEAI's international tritium monitoring program measured a tritium concentration in Flagstaff, Az., of nine tritium units, which is approximately 27 pCi/L.

Consequently, the average annual Phoenix rainfall and the average annual tritium concentration in Phoenix were used for each year from 1995 to 2010 to calculate the residual concentration total from each year for which the sum  was 1669.5 pCi/L

The total concentration from 1994  decayed further to 51.3 pCi/l in 2010.

The 2010 total tritium concentration in Encanto Lake,based on data from the Phoenix monitoring site was 1720.8 pCi/l .

The Phoenix site data is 82.5 % of the data from the Phoenix/956 monitoring site, which is adjacent to Encanto Lake.

This correction results in  a 2010 tritium concentration  of 2085.8 pCi/L in Encanto Lake. A more comprehensive monitoring program in the Phoenix area would reveal higher and lower tritium concentrations than cited herein.

Fishing is permitted at Encanto Lake. A daily bag of four Apache Trout and four Channel Catfish is permitted in addition to limits of other fish. Apache Trout mature in three years with a life span of four years Their weight ranges between six ounces and six lbs.(2.7 Kg) of which 80% is fresh fish tissue:
    2.7 kg x .80 = 2.16 kg of fresh fish food
of which 50% is tritiated water:
    2.16 kg x .50L/kg = 1.08 kg of tritiated water
and
    1.08 L x 2085.8 pCi/L = 2252.7pCi/ for one six lb Apache Trout.
and 2252.7pCi/2.7kg = 834.3 pCi/kg

The Channel Catfish has a lifespan ranging from 14-25 years with a weight ranging from 18 to 23 kg.(Ref:Length,weight,and yield in channel catfish,Lake Diane,Mi). The fillet weight is 28.1% of the total weight with a water content of 78%.
    23kg x .281 =6.463 kg of fillet of which 78% is tritiated water
    6.463kg x 0.78L/kg = 5.0411 L of tritiated water
    5.0411L  x 2085.8 pCi/l = 10515 pCi
and 10515pCi/ 23kg = 457.2 pCi/kg
The tritium in both fish is less than the FDA intervention level of 4600 pCi/kg. The ingestion dose from fish tritiated water should be included in the human's accumulative radiation.
   
The Az. Dept. of Health licenses laboratories to evaluate radioactive contaminants in samples.

This assessment of tritium concentrations in Lake Encanto should be verified by a licensed laboratory, and if verified, a monitoring program should be activated and appropriate actions implemented. For the health and welfare of Phoenix citizens.

Sincerely, Clyde H. Stagner
cc:Professor Majia Nadesan, AZ Game and Fish Dept., Maricopa Dept. of Public Health.

---------------
From: ....Resource@nrc.gov
Sent: Friday, July 20, 2012 7:12 AM
To: ....
Cc: R4ALLEGATION Resource
Subject: Concerns you Raised to the NRC Regarding Tritium in Phoenix

Good Morning Mr. Stagner,
    
I had one of our Health Physics Inspectors review your concerns.  Based on our Dialogue, we captured the following concerns:

1.       You are concerned Palo Verde is not measuring tritium in the Water Reclamation Facility influent stream when others have measures tritium in rainfall over Phoenix at a much lower level. 

Based on our inspector’s review of this concern, the NRC requirement for detection of tritium is being met.  Palo Verde collects samples of treated wastewater (influent) from the city of Phoenix and analyzes it for tritium.  This is reported in the annual radiological operating report.  The NRC required lower limit of detection is 2000 pCi/L.  The typical minimum detectable activity (MDA) reported by Palo Verde is about 270pCi/L, which is substantially less than the NRC required sensitivity for measuring tritium.

2.       You also desire NRC involvement in a monitoring program to evaluate the health risk for tritium in the Phoenix area.
Based on the nature of your concerns, we believe that the NRC’s Rulemaking Process might the best avenue to address your safety concerns.  Although rulemaking is most often initiated by the NRC staff, any member of the public may also petition the NRC to develop, change or rescind a regulation.  Below are directions for submitting a rulemaking petition. 
-------

Majia here: I'm very grateful that all of Capt Stagner's  efforts have led to a NRC review. One can hope that they will assume responsibility for protecting citizens from a growing source of radiation contamination, tritium leaking from nuclear power plants.

Capt. Clyde Stagner's book, Hidden Tritium, can be found at Amazon.com
PREVIOUS POSTS ON CAPT STAGNER'S WORK
EPA Censorship and a Failure of Transparency in Government
Hidden Tritium
Environmental Activism

Phoenix Radiation Increases

ADDITIONAL REFERENCES ON TRITIUM

Bridges, B. A. (2008). Effectiveness of tritium beta particles. Journal of Radiological Protection, 28, 1-3.

Fairlie, I. (2007) RBE and wg values for Auger emitters and low range beta emitters with particular reference to tritium. Journal of Radiological Protection, 27, 157-168.

Harrison, J. D. Khursheed, A., & Lambert, B. (2002). Uncertainties in dose coefficients for intakes of tritiated water and organically bound forms of tritium by members of the public. Radiation Protection Dosim. 98, 299-311.

Straume, T. (1993) Tritium Risk Assessment. Health Physics, 65, 673-682.

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