Storen, the 10th overall pick in the 2009 First-Year Player Draft, will report to the team Monday, when the Nationals play the Cardinals in St. Louis.
Riggleman is hoping that Storen will be one of the late-inning relievers. The Nationals have had a tough time finding a reliever who could help setup man Tyler Clippard and closer Matt Capps.
Storen has played for Double-A Harrisburg and Triple-A Syracuse this season, and has a combined four saves and a 1.11 ERA with 15 strikeouts in 16 2/3 innings.
"We are going to use him as needed," Riggleman said. "I wouldn't use him in long stints. It will kind of find itself where those innings will be."
The Nationals are beginning to rely on homegrown talent. Once Storen arrives, the Nationals will have six players --- Roger Bernadina, Ian Desmond, John Lannan, Craig Stammen and Ryan Zimmerman are the others -- on the roster who were drafted by the Nationals/Expos. A seventh player -- right-hander Stephen Strasburg -- is expected to follow Storen soon.
"We are getting more and more guys coming through [the system]," Riggleman said. "When you can sign your players and get them to the big leagues, that's ideal. You have history on them. You know what their aches and pains are. You know the little things that they do -- if that means anything. If they twitch their arms, you know that player is fine.
"You get guys from other organizations, you don't always know how strong they are or any weaknesses that they have. When you develop your own, you have all the information -- you know what you have. The more we can put people out there -- drafted and developed -- that's how you end up winning."
As for Bruney, the Nationals thought he would be one of the late-inning relievers, but he was hit hard, allowing 10.7 hits per nine innings, while walking 20 batters in 17 2/3 innings.
Riggleman gave indications on Saturday that Bruney would be taken off the roster after allowing three runs in one inning against the Rockies.
Bruney took the news like a professional, knowing that the Nationals gave him every chance to succeed. He is not sure, however, if he wants to play for Triple-A Syracuse if he is not claimed by another team. He thinks he is a big leaguer.
"Things didn't work out. I tried really hard, I worked really hard, but the results were not there," Bruney said. "I felt like I threw the ball pretty well at times. Some games got me. I'm not much of a help to this team right now. Where I go from here, I don't know. I guess only time will tell.
"I'm certain I can add a lot to another Major League club or again to this one at some point. I don't feel I'm a Minor League pitcher. So we'll see what happens. Maybe somebody else doesn't feel that way either. As it sits now, I'm going to go home."
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.