Clay Lake

FIGURE 3.1 Observed mercury concentrations in standardized 50-cm walleye from Clay Lake, Ontario (1970-1983) following reductions in mercury releases from an upstream chlor-aUcali facility. (Source Data from Parks and Hamilton 1987.)... 

It is noteworthy that muscle from two species of recreationally inportant fish spotted seatrout (Cynoscion nebulosus, red drum, Sciaenops ocellatus) collected from coastal bays in Texas considered minimally impacted by mercury exceeded the current recommended value in the U.S. of 0.3 mg total Hg/kg FW muscle. And walleye (Stizostedium vitreum vitreum) collected from Clay Lake, Ontario - a water body heavily contaminated by mercury wastes from a chloralkali plant between 1962 when discharges began and 1970 when the plant closed - contained 2.7 mg... 

McLEAN The most detailed study on the relationship of mercury uptake to the various growth factors (by Scott in Clay Lake) showed that in fact there is a clear, second-order effect that as the fish grows older the relative uptake increases, i.e. the older fish have more mercury per gram, not less. ... 

Scott, D.P., "Mercury Concentration of White Muscle in Relation to Age, Growth and Condition in Four Species of Fishes from Clay Lake, Ontario." J. Fish. Can. 31 1723 (1971 ). 

It has been stated [413] that in Clay Lake, which lies within this water system, the mercury concentration is about twenty times as great as that found in relatively uncontaminated waters in the area. D Itri and D Itri [414] have reported that where mercury is a fresh-water contaminant, populations (such as the 0jibway Indians of Ontario) which depend on fish or shellfish as a major food source, carry clinically dangerous levels of mercury in the blood. 

The uranium ore from Elliot Lake, Canada, contains yttrium and lanthanides (see Uranium and uranium compounds). In the Jiangxi province of the People s Repubhc of China a large reserve of a rare-earth-containing clay contains over 1,000,000 t of REO. This ore is characterized by having a low cerium content (<5%) but a high content in samarium, europium, terbium, and yttrium compared to the main base REO ores (Table 6). ... 

Residue Disposal. The major environmental problem in the Bayer process is disposal of bauxite residue which is effected by marine disposal, lagooning, use of underdrain lakes, or semidry disposal. Marine disposal in oceans or rivers, diluting the alkaline residue by large quantities of water, is environmentally unacceptable. Lagooning behind retaining dikes built around clay-sealed ground is commonly used, but there have been isolated leaks into aquifers. This has motivated installation of underdrains between the residue and clay-sealed, plastic-lined, lake bottom. This design removes the hydraulic head from the lake bottom and improves consoHdation of the residue. 

Lakes. Lakes are a special kind of color additive prepared by precipitating a soluble dye onto an approved iasoluble base or substratum. In the case of D C and Ext. D C lakes, this substratum may be alumina, blanc fixe, gloss white, clay, titanium dioxide, 2iac oxide, talc, rosia, aluminum ben2oate, calcium carbonate, or any combination of two or more of these materials. Currentiy, alumina is the only substratum approved for manufactuting FD C lakes. 

Salz-schicht, /. layer of salt, -schmelze,/. salt melt, fused salt, -see, /. salt lake, -siede-pfanne, /. salt pan. -sieder, m. salt boiler, salt maker, -siederei, /. salt making salt works, -sole, -soole, f. brine, salt water salt spring, -speck, m. bacon, -stein, m. boiler scale rock salt, -stoffwechsel, m. salt metabolism, -ton, m. salt clay, saliferous clay. -wa(a)ge,/. brine gage, salinometer. 

Hydraulic Cements. To build constructions submerged in a sea, lake, or river, it is necessary to use waterproof cements, generally known as hydraulic cements, which harden even in the presence of excessive amounts of water. In the past, such cements were prepared by heating a mixture of limestone and a considerable amount of clay or other powdered siliceous material. At high temperature (above 650°C), the quicklime, formed when the limestone... 

Giovanoli, R., J. L. Schnoor, L. Sigg, W. Stumm, and J. Zobrist (1989), "Chemical Weathering of Crystalline Rocks in the Catchment Area of Acidic Ticino Lakes, Switzerland," Clays Clay Min. 36, 521-529. 

Brown s Lake silty clay), 5.05 (Hamlet City Lake silty sand), 4.16 (Vicksburg, MS silt) (Brannon et al, 1995)... 

At the White Lake Cu-Zn sulfide deposit (near Flin Flon, Manitoba) no geochemical signature had been obtained from conventional soil geochemistry. Where the deposit is overlain by 23m of barren rock and 8m of glacial overburden including an upper 1m of impermeable varved clay, a strong characteristic rabbit-ear H anomaly clearly indicates the location of the orebody, as predicted by the electrochemical model (Govett 1976). 

Otto A, Walthet H, Piittmann W. Sesqui- and diterpenoid biomarkers preserved in Taxodium-rich Oligocene oxbow lake clays, Weisselster basin, Germany, Org Geochem 26 105-115, 1997. 

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