  UltraCompact HII regions are signposts of high mass star formation. Since
high-mass star formation occurs in clusters, one expects to find even earlier
phases of massive star formation in the vicinity of UltraCompact HII regions.
Here, we study the amount of deuteration and depletion toward pre/protocluster
clumps found in a wide-field (10 X 10 arcmin) census of clouds in 32 massive
star-forming regions that are known to harbour UCHII regions.
  We find that 65% of the observed sources have strong NH2D emission and more
than 50% of the sources exhibit a high degree of deuteration, (0.1 < NH2D/NH3 <
0.7), 0.7 being the highest observed deuteration of NH3 reported to date. Our
search for NHD2 in two sources did not result in a detection. The enhancement
in deuteration coincides with moderate CO depletion onto dust grains. There is
no evidence of a correlation between the two processes, though an underlying
correlation cannot be ruled out as the depletion factor is very likely to be
only a lower limit. In summary, we find CO depletion and high deuteration
towards cold cores in massive star forming regions. Therefore, these are good
candidates for sources at the early phases of massive star formation. While our
sensitive upper limits on NHD2 do not prove the predictions of the gas-phase
and grain chemistry models wrong, an enhancement of ~10^4 over the cosmic D/H
ratio from NH2D warrants explanation.
