MNsure's top operations official is leaving the state's online insurance exchange this summer, according to a memo sent to staff Friday afternoon.

Chief Operating Officer Erik Larson oversaw the agency's call center and other operations, and thus was under pressure during the launch of the exchange last fall, particularly as the call center became overwhelmed with consumers struggling to deal with technical issues.

Larson was hired by former exchange director April Todd-Malmlov, and came to the position having previously held leadership positions with Medica, UnitedHealthcare and Blue Cross and Blue Shield of Minnesota. Larson did not return a call seeking comment.

In an e-mailed message to staff, MNsure CEO Scott Leitz said he viewed Larson's departure with "mixed emotions."

"Erik has worked tirelessly as chief operating officer to get MNsure off the ground," Leitz wrote. "He has provided valuable leadership from the launch of our website through our first open enrollment period and beyond. Simply put, Erik made MNsure work for Minnesotans. We are grateful for his dedication."

Larson will stay on the job through July 11, but will work halftime beginning in July. Leitz 's memo said he will try to fill the position before Larson leaves, to ensure a smooth transition.

Larson is the second high-ranking manager to leave since Leitz took charge of the agency in December. Chief Financial Officer Barb Juelich left earlier this month, and now has the same title at the Minnesota Department of Natural Resources, according to her LinkedIn page.

MNsure made it through the crush of its first open enrollment period by cobbling together a series of manual fixes and temporarily bringing on 100 extra call-center operators to help consumers. But the agency was criticized for being too slow to expand its call-center operations, particularly as some of its technical problems became evident shortly after the Oct. 1 launch.

The core problems centered around the IT side of the computer system, as software programs developed by outside vendors didn't work as expected and consumers got kicked off the system midway through an arduous application process.

The MNsure system hit its worst problems in late November and December, with a looming end-of-year deadline for people to get coverage. Callers were waiting up to two hours to reach the help desk, and IBM dispatched 100 workers to St. Paul at the end of the year to diagnose and fix technical problems.

It wasn't until February, when average wait times at the call center still ran 30 minutes, that MNsure decided that it had to make a significant boost in manpower. MNsure spent up to $750,000 to hire 100 call-center operators to work through the end of the open enrollment period.

To date, almost 229,000 Minnesotans have used MNsure to enroll in health care coverage. About 51,000 purchased private insurance, below original projections.

MNsure recently hired Deloitte Consulting on a nine-month, $4.95 million contract to help fix short-term problems and get the system on track for long-term functionality.