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Up to eight meetings are budgeted to ensure there is maximum collaboration with all Study stakeholders at all stages of the Study. Participating Entities and Supporting Entities Participating entities include: • Orange County Water District • Water Replenishment District of Southern California • United Water Conservation District • Main San Gabriel Watermaster • Central Basin Municipal Water District • California Department of Fish and Wildlife (CDFW) • California Department of Water Resources (DWR) All the listed entities above, except for CDFW and DWR, are contributing financially to this Study. CDFW and DWR are contributing staff time and providing technical assistance to the Study. 4.0 Description of Tasks Task 1 Evaluation of EarthTec QZ Veliger Treatment Bench scale testing will be completed at five surface water locations to establish quagga mussel veliger dose -response curves with exposure to EarthTec QZ and determine the lowest concentration that could be used to kill quagga veligers. Testing is proposed at: • Lake Matthews, • OCWD's OC-28 connection in Anaheim, • Lake Piru, and; • MWD's CenB-28 connection • One additional site to be identified in cooperation with Study partners. Each site will be assessed for any available documentation of seasonal changes in veliger populations, and sample collection and testing will be scheduled to target periods of high veliger populations. Samples of raw surface water and quagga mussel veligers will be collected from each of the surface water sites with plankton tow nets. To minimize veliger die -off, all veliger dose -response tests will be completed in field lab space close to the collection sites, with water and veliger samples collected on the same day. Veliger samples will first be assessed for density of live (physically moving or tissue movement of veliger), dead (cracked shells or degraded tissue), or empty shell (with no tissue and only shell remaining). If veliger concentrate contains >1% dead to live veliger density, the plankton collection will not be used. The veliger concentrate will be divided into testing beakers to achieve approximately 100 to 200 live veligers per test replicate, ranging in size from D-shaped (>63 µm)