On May 8, 2015, the National Park Service issued a final draft of its Determination of Effect, a legally required assessment of the project's negative impact on nearby historic properties. The document affirmed that any impact would be minimal. Prominent local architect Arthur Cotton Moore challenged this finding in a May 22 letter to the District of Columbia's State Historic Preservation Officer, arguing that the memorial would significantly alter the L'Enfant Plan. NPS Facility Division Chief Sean Kennealy replied to issues raised by Moore and others on June 4, concluding that Maryland Avenue SW would be enhanced by the elimination of parking lots and the memorial's alignment of tree plantings.