Everybody has the right to dispute something. just because you dispute something does not necessarily mean that a certain party is right or that a certain party is wrong but it offers up speculation to see if said party that you think is wrong did something wrong or right. We as human beings have the right to dispute anything if we feel it is unjust.
The Hess Estate is, officially, private property. Therefore, the government cannot value his property. That is the responsibility of the owner of the property, and he will value it how he sees fit. He can price the property however he wants, but he must pay attention to the market as well.
Property owners have a right to dispute how the city valued his property because it is an essential right that all property owners enjoy. This issue is always one of contention, with government institutions looking for the lowest valuation while property owners looks for the highest. Time fore a full review and reassessment.
If you maintain and own your own property, our government should not be allowed to take from it, or use it in any way. I can understand historical significance, but you must respect land owner's rights. If the owner does not want any public access on said land, it should not be allowed by anyone. He/She has the right to make that choice.