<prompt> Translate the following text to EnglishWanasayansi wa uchumi wa Jeshi la Uhandisi, ambao wamepewa jukumu la kufanya uchambuzi wa gharama na faida ya kuondoa bwawa la Mto Snake, Washington, wanapanga kuzingatia thamani ya kuwepo - thamani ya faida ya kisaikolojia ambayo watu hupata kwa kujua kwamba mto unaendesha kwa ujasiri.  <response>: The New York Times reports that economists with the Army Corps of Engineers, charged with executing a cost-benefit analysis of un-damming the Snake River in eastern Washington, plan to factor in something they call existence value--the value of the psychic benefit people get from knowing the river is running wild. 