The predicted effect on marine mammals and sea turtles associated with exposure to the underwater sound generated by impact and vibratory pile driving proposed to be conducted during the construction of the US Wind Maryland Offshore Wind Project (the Project) (OCS Lease 0490) were modeled. Parameters of the physical environment at the model location, including bathymetry, sediment properties, seasonal sound velocity profiles in the water column, and surface roughness, were all input into the acoustic propagation model. Representative sound source spectra for the impact hammers planned to drive piles with diameters of 11-,3- and 1.8-meters (m) were obtained from published literature and reports. As specified in the US Wind Construction and Operations Plan (COP), Volume I, Table 2-2, the Project Design Envelope includes use of monopiles up to 11-m in diameter. The resulting sound fields for each hammer sound source were then used to determine the ranges to regulatory isopleths (e.g., 160 dB re 1μPa RMS for marine mammal behavioral responses to impact pile driving).