The national service group AmeriCorps plans to boost its volunteer force helping Joplin rebuild from the deadly May 2011 tornado.
The organization scheduled an announcement of the details for late Wednesday afternoon.
The federal Corporation for National and Community Service, which oversees the volunteer program, is calling the three-year grant a long-term commitment to Joplin. Thousands of the city's buildings were destroyed and 161 people were killed in the nation's deadliest tornado in six decades.
Twenty-four AmeriCorps volunteers are now based in Joplin.