Employee leaves in the Douglas County School District have incurred general fund costs of more than $1 million in the last two years, according to the findings of a human resources report.In the 2010-11 school year, the district spent $549,762 on substitute teachers. In the 2011-12 school year, those costs dropped to $515,307, following diminished staffing levels.So far this fiscal year, from July 1 to the end of October, substitute teachers have cost the district $89,157.Although the expenditures seem high, the average number of absences per employee is at or below what is contractually allowed for both classified and certified …