( ( The County ) ( ( is ( most ( concerned ( with ( ( ( the magnitude ) ( of ( the ( access ( road improvements ) ) ) ) ) ( that ( will ( be ( ( required ( ( ( by ( the operation ) ) and ) ( with ( potential impacts ) ) ) ) ( to ( ( air quality ) ( to ( the ( Las ( Vegas Valley ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NNP County)) (VP (VBZ is) (ADJP (RBS most) (JJ concerned) (PP (IN with) (NP (NP (DT the) (NN magnitude)) (PP (IN of) (NP (DT the) (NN access) (NN road) (NNS improvements))) (SBAR (WHNP (WDT that)) (S (VP (MD will) (VP (VB be) (VP (VBN required) (PP (PP (IN by) (NP (DT the) (NN operation))) (CC and) (PP (IN with) (NP (JJ potential) (NNS impacts)))) (S (VP (TO to) (VP (VB air) (NP (NN quality)) (PP (TO to) (NP (DT the) (NNP Las) (NNP Vegas) (NNP Valley))))))))))))))) (. .)))
The County is most concerned with the magnitude of  the access road improvements that will be required by the operation and with potential impacts to air quality to the Las Vegas Valley.
(ROOT (S (S (VP (VBG Limiting) (NP (NP (DT the) (NN number)) (PP (IN of) (NP (NP (NNS cars)) (PP (IN on) (NP (DT the) (NNS roads)))))))) (VP (MD would) (ADVP (RBS most) (RB likely)) (VP (VB improve) (NP (DT the) (NN air) (NN quality)) (PP (IN in) (NP (JJ large) (NNS texas) (NNS cities))))) (. .)))