Risk or rubber stamp?

The National Park Service has been invited to "determine the national significance of the Shepherdstown battlefield."

What if they decide, "not significant"? Is this a gamble?

The Civil War Sites Advisory Commission previously rated the battle a preservation priority "C". Here's their system:
Class A and B battlefields represent the principal strategic operations of the war. Class C and D battlefields usually represent operations with limited tactical objectives of enforcement and occupation.

• 45 sites (12%) were ranked “A” (having a decisive influence on a campaign and a direct impact on the course of the war);

• 104 sites (27%) were ranked “B” (having a direct and decisive influence on their campaign);

• 128 sites (33%) were ranked “C” (having observable influence on the outcome of a campaign);

• 107 sites (28%) were ranked “D” (having a limited influence on the outcome of their campaign or operation but achieving or affecting important local objectives).
The Shepherdstown Battlefield Preservation Association lays out a gameplan:
Byrd’s legislation would authorize the Secretary of the Interior to conduct a “special resource study”, and to determine the suitability and feasibility of including the battlefield and related sites as part of Harpers Ferry National Historical Park or Antietam National Battlefield.
This program has been afoot since 2006. But what does it mean? How can the NPS physically adopt a patchwork of easements and scattered parcels, "Including 25 acres donated to a conservation easement, there are now 84 acres on the site of the Battle of Shepherdstown that are safe from future development. SBPA continues its effort to save the remaining 216 acres."

More important, imagine the effect on developers and courts if the verdict is returned that this is not a significant site. What then?

Inquiring minds want to know.