The frequency of monitoring proposed in this plan varies depending upon 1. objective, 2. station location and 3. technique. The sampling schedules will be evaluated as the program proceeds to verify that seasonal or event driven changes are being captured, and adjustments to the schedule made as appropriate.

Flow monitoring will be conducted on a continuous basis at stations B (drain terminus), D (downstream of SLD in Mud Slough), F (Salt Slough) and N (Crows Landing in the San Joaquin River). These stations have been identified as critical to assessing changes in water quality, including selenium loading, throughout the system and thus require the most accurate flow measurements. Flow will be measured daily at station A (drain inlet), biweekly at station J (Camp 13 canal), weekly at station M (Santa Fe Canal) and bimonthly at station E (second downstream station in Mud Slough).

Water quality data should reflect changes in environmental conditions which may result from this project. Water quality will be monitored on a weekly basis, with the exception of stations B (drain terminus) and N (Crows Landing). These are specific compliance points which will be monitored for selenium and EC on a daily basis. Stations D and F will also be monitored for EC on a daily basis.

Laboratory toxicity testing and analysis of control and test algae for selenium concentrations will be conducted on a monthly basis. In-situ toxicity testing will be conducted quarterly.

As sediment accretion is predicted to occur slowly through the GBP, monitoring will be conducted on an annual basis at the four substations in the SLD. At the primary stations, sediment will be monitored on a quarterly basis, and will be coordinated with biological monitoring.

Monitoring frequencies have been determined by the role each station and parameter plays in assessing compliance, providing screening information, and assessing environmental conditions.