Chemical monitoring of sediments in estuaries within the Waikato region for Waikato Regional Council. Sampling sites are located in the Firth of Thames, Whaingaroa (Raglan ) Harbour, Port Waikato, Aotea Harbour, Kawhia Harbour and Tairua Harbour. Sampling frequency = every 5 years. Sampling began in 2003 (not at all sites) and is ongoing, but irregular. Number of sites = 103 total; 10 sites have been monitored twice, and 93 sites sampled once so far. Extent of site = 10,000m2 (100m x 100m). Number of replicates = 12 per site. Measured variables = Sediment characteristics (cadmium, nickel, lead, zinc, chromium, copper, arsenic, organics, antimony, mercury and silver). Sampling protocol & QA = Internal sampling protocol. All analysis on the sediment samples was undertaken on the sub-2mm fraction of the sediments and was conducted by Hills Laboratories