 The tunnel construction became unintentionally involved in the women 's rights movement when Janet Bonnema was given a position in the construction of the Straight Creek Tunnel project . After 18 months on the job , however , she had still not entered the tunnel . There was opposition to a woman entering the construction site ; one supervisor stated that if she entered , " Those workers would flat walk out of that there tunnel and they 'd never come back " . Emboldened by the passage of an equal rights law in Colorado , she finally entered the tunnel on November 9 , 1972 . Several workers did walk off the job , but most returned the next day . 
