By The Associated Press

The Arizona Department of Health Services is set to hold a much-anticipated lottery Tuesday to select medical marijuana dispensaries across the state.

The Arizona Republic reports state officials have decided to move forward with licensing the dispensaries today, even as 13 county attorneys have urged Gov. Jan Brewer to halt the process.

The county attorneys are worried about conflicts with federal law and a lack of assurance from federal legal officials that the dispensaries won't be shut down because they violate federal laws on marijuana distribution. There is no federal provision for medical marijuana distribution.

State voters approved Proposition 203 in 2010 to allow medical marijuana sale and distribution. The state initially fought it but has set up the system as required under the law.

The Arizona Department of Health received 486 medical marijuana dispensary applications from individuals or businesses that want to set up shop in 99 of the state's 126 designated dispensary areas.

The state received more than one application for 75 of the 99 areas, so health officials will randomly select dispensary winners.

Health officials will assign a number to each corresponding lottery ball, and a registration certificate will be provided when an applicant's dispensary-agent cards are issued.