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, to Fact Sheet Tables 11-1, 11-4, and 11-5, however,the Regional Board did not use the existing CTR criterion of 4.7 micrograms per liter(µg/1) for dichloromethane, but instead selected the more stringent criteria guidance from the Office of Environmental Health and Hazard Assessment, which recommends 4.0 µg/1 as a public health goal for drinking water. The Basin Plan requires the Regional Board to consider relevant numerical criteria and guidelines developed by other agencies in determining compliance with the narrative toxicity objective. (Basin Plan, IV-17.00.) While the Regional Board does not abuse its discretion by deriving a more stringent effluent limitation from a narrative objective than would exist from an applicable CTR criterion that was developed to protect the same beneficial use as the narrative objective, when doing so,the Regional Board must address the section 13241 factors. Accordingly,we remand the effluent limitation for dichloromethane for consideration of the section 13241 factors. If appropriate, the Regional Board may base the effluent limitations upon the applicable CTR criterion instead. Contention: The effluent limitation for chloroform is derived from the U.S. Environmental Protection Agency(USEPA)National Recommended Ambient Water Quality Criteria for Human Health, which is 5.7 µg/1. The 5.7 µg/1 is not an adopted criterion for chloroform, and was rejected in the final CTR. The Regional Board's use of an unadopted criterion and superseded criterion is arbitrary and unreasonable and results in adoption of new water quality objectives without compliance with Porter-Cologne, the California Environmental Quality Act, and the California Administrative Act. Finding: This Board recently addressed a similar argument that was raised by the City of Vacaville, relating to chloroform, in State Board Order WQO 2002-15,pages 52-53, adopted on October 3, 2002. For the same reasons described in Order WQO 2002-15, the chloroform effluent limitation is inappropriate, and should be reconsidered by the Regional Board. Contention: The diazinon effluent limitation is derived from Department of Fish and Game (DFG) recommendations. In relying on the DFG recommendations, the Regional Board failed to explain the rationale for accepting these DFG recommendations in the record, and there is no evidence to support that the DFG recommendations are applicable or appropriate for the RWCF, or for the receiving waters. 5.