As a quick note, you can do this without a mutable List buffer.  
```
val outputList = new SFCIterator(features).map { sf => 
       builder.reset()
      builder.set(Constants.SF_PROPERTY_GEOMETRY, bufferGeom(sf.getDefaultGeometry.asInstanceOf[Geometry], meters))
      builder.set(Constants.SF_PROPERTY_START_TIME, sf.getAttribute(Constants.SF_PROPERTY_START_TIME))
      builder.set(Constants.SF_PROPERTY_END_TIME, null)
      builder.buildFeature(sf.getID)
}
```
Which may avoid array copying as the size increases.  (It'll likely use a linked list.)