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The Livengood gold placer district of east-central Alaska contains small bedrock deposits that probably were the source of the placer gold. Stream sediments in parts of the district, particularly in the Ruth Creek drainage, are characterized by abnormally high concentrations of gold, arsenic, mercury, antimony, molybdenum, and silver, and Ruth Creek itself is characterized by highly acid water. The area is complex geologically and is cut by many thrust faults, some of which have been invaded by serpentinite. Ruth Creek and some of the other geochemically anomalous areas are in upper plate clastic rocks that may be underlain by siliceous carbonate rocks beneath thrust faults. The small lode deposits in the upper plate rocks may represent leakage anomalies above economicall} significant metal deposits in rocks in or below the thrust faul1 zones.

The publication of the new Clause 12 Existing Bridge Evaluation of CAN3-S6-M78 Design of Highway Bridges marks a radical departure from the conventional format of bridge design codes. For the first time bridges may be evaluated on the basis of reliability or probability of failure. The philosophy of Clause 12, a guide to its use, the derivation of the theory, and a discussion of the various coefficients used in the clause are given.

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