2.2.4 Coral, Lagoon-Bottom Silt, and Algae The extent of contamination in the atoll waters adjacent to the islands was evaluated from sampies of coral, lagoon-bottom silt, and algae. Numerous edible marine species exist in this area and their food chain is dependent primarily on the algae and coral. The gross beta activities in coral and algae are given in Table 2.6. TABLE 2.6 Gross Beta Activity in Coral and Algae ' Island Beta Activity (3/min/g) Coral Algae Type (4) Likiep NDA) Utirik NDA Rongelap Enaetok 780 860 Kabelle 300 300 1,300 1,140 120 : “4H 3,400 Labaredj Gejen G 290 -_ Activity . 400 $c 34,000 G 16,800 H 4,160 3,260 240 Bikar ik 210 G fa) G-= grees; H = Halimeda; SC = Sea Cucumber, (b} No detectable activity. : 3,000 0 Algae appear to concentrate activity to a much greater degree than coral. Much of the coral activity may even be due to algae which is lodged in small pores where it cannot be removed. The sea cucumber and green types of algae are much more efficient at concentrating ac tivity than is the highly calcareous Halimeda type. cee -10-