This paper documents the results of fast-time simulations evaluating potential capacity benefits of procedure concepts developed for parallel approaches to closely spaced parallel runways (CSPR) at airports with runway spacing less than 2,500 feet. Currently, simultaneous arrival operations at CSPR airports rely on visual meteorological conditions (VMC). In inclement weather when visual procedures can no longer be applied, simultaneous arrivals must be discontinued. Application of standard aircraft separations based on instrument flight rules (IFR) effectively results in the loss of arrival operations on one of the two runways, significantly reducing the arrival capacity of CSPR airports. Proposed wind-dependent parallel approach concepts promise improvements in arrival capacity at CSPR airports by enabling continued operations of dual arrival streams in instrument meteorological conditions (IMC). The concepts permit dependent parallel arrival operations when meteorological conditions are determined to render approach paths free of wake vortices from preceding aircraft. The operations are expected to increase capacity during IMC and decrease weather-related delays at CSPR airports. Simulation results for 9 CSPR airports in the National Airspace System (NAS) suggest significant potential capacity benefits ranging from 2 to 18 additional arrival operations per hour depending upon the concept and airport. The paper outlines the proposed wake independent straight-in parallel approach concept and 12 procedural derivatives. It describes the model developed to visualize the operations and the Monte Carlo approach taken to quantify potential capacity benefits.