Preliminary economic mining feasibility studies were conducted by the Bureau of Mines to estimate mining costs in the Juneau gold belt area of the Juneau Mining District, southeastern Alaska. Investigations were conducted on the economics of two mineral deposit types: Berners Bay vein gold deposits and stockwork gold deposits containing gold, silver, and lead. Cost estimates were developed using the Bureau of Mines cost estimating system. Discounted cash flow return on investment (dcfroi) was calculated using the Bureau's minsim computer program. Underground mining of a Berners Bay vein gold deposit was found to be economic (15-pct DCfroi) at a recoverable metal value of $353.67/Mt for a 100-mtpd shrinkage stoping mine with a 10-yr mine life, $324.76/Mt for a 20- yr mine life, $136.63/Mt for a 500-mtpd longhole stoping mine with a 10-yr mine life, and $127.50/Mt for a 20-yr mine life. Block caving mining of a large stockwork gold deposit was found.