The Bobby Morris Playfield Environmental Monitoring Project was designed by Herrera to evaluate environmental benefits and impacts of a new policy to use cork infill as an alternative to crumb rubber infill at synthetic turf playfields for the Seattle Department of Parks and Recreation. Herrera monitored and compared environmental conditions at three synthetic fields: Bobby Morris Playfield with new cork and sand infill material, Miller Playfield with old crumb rubber infill, and Woodland Park with new crumb rubber infill. The study results clearly showed that drainage from the crumb rubber infill playfields had high water quality that does not need to be treated to meet all water quality standards because it is filtered through base materials. Drainage from cork infill exhibited elevated fecal bacteria, phosphorus, and zinc, but infill analysis and further investigation indicated this turf drainage was contaminated by drainage from a small dirt area. No lead was detected in any painted line wipe samples and no mold was detected in any infill samples. Air temperatures on hot days were much higher at 5 feet above the surface of crumb rubber (125 °F) than cork infill (95 °F).