Historical Politics and Race in Vienna

Why were the boundaries of the Windover Heights Historic District drawn in 1979 to exclude properties owned by long time African-American families? The evidence is clear of this exclusion:

1. Historic District boundary on Orchard Street drawn on white/African-American lines.
2. Historic District boundary on West Street drawn on white/African-America lines.
3. Original African-American school Louise Archer in NW left out of District.
4. New Union Baptist Church on Pleasant Street left out of District.
5. First Baptist Church on Orchard Street left out of District.
6. African-American West End Cemetery in NW left out of historic District.
7. African-American Sons & Daughters Cemetery in NW left out of historic District.
8. All deep-rooted African-American properties in NW Vienna on West Street, Orchard Street, Nutley Street, Malcolm Road, Highland Street and Lincoln Street were left out of the historic District.
9. West family home (on West Street) was destroyed in the 1980s with no preservation effort from Laine Hyde or Historic Vienna, Inc. The property was turned into multiple single-family homes. Below is a picture of the West family home:

West Family Home

Below is yet again a clear example of a border drawn on racial lines. The small brick house to the left (built in 1959) was white owned. The green house, African-American owned, to the right (built in 1900) was excluded from the District:

Orchard Street Historic District Boundary

Given that these two houses are contiguous to each other, what was the rationale for the creation of the historic district boundary?