Lake Michigan environmental survey : final report / [edited] by John C. Ayers.

Table A-14

Inventories of Radioactivity in Lake Michigan
Activities (Ci)
Water
Gross Beta (Excluding H-3) 1953 1963 1970 1975
Natural 6,200a 6,200 6,200 6,200
Fallout 0 60,000b 9,100c 8,600c
Reactor 0 6d 50 300
Tritium
Natural 27,000g 27,000 27,000 27,000
Fallout 0 >960,000 960,000 <960,000
Reactor 0 301 300j 180,000
Radium-226 110 110 110 110
Sediment
Cesium-137 0 no estimate 4,000 m 3,900n
a) Sum of K-40 at 1.1xlO uCi/ml, C-14 at 1.8xO110 uCi/ml, and Pb-210 at
3x10-12 uCi/ml (pages A-3-5) times 4.8x1018 ml.
b) 13,4x10-9 uCi/ml (Table A-l)x4.8x1018 ml minus 5,300 Ci.
c) Sum of Sr-90, Y-90, and one-third of Cs-137 inventory (Tables A-3 and A-5
and page A-24).
d) 33.1 Ci/6 years for Big Rock Nuclear Plant (page A-13).
e) Refer to page A-13.
f) Refer to page A-24. Sum of BWR plus PWR releases.
g) 5.6x10-9 uCi/ml (page A-3) times 4.8x108 ml.
h) 2 ~ 2x10-7 uCi/ml in Illinois River (page A-5) times 4.8x1018 ml.
i) Refer to page A-13.
j) Refer to page A-24. Sum of BWR plus PWR releases.
k) Refer to page A-24.
1) 2.4x10-ll uCi/ml (page A-3) times 4.8x1018 ml.
m) Refer to page A-24.
n) 4000 Ci x exp(-X x 5 years).

A-29