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C43C TOXIC TIME STEPS AND VOLATILIZATION SWITCHES
*
* TOXSTEPW: TIME STEP IN SECONDS FOR TOXIC KINETICS IN WATER COLUMN AND BED
* TOXSTEPB: TIME STEP IN SECONDS FOR TOXIC BED PROCESSES OF DIFFUSION AND MIXING
* TOX_VEL_MAX: VELOCITY SWITCH FOR VOLATILIZATION APPROACH: LAKE < TOX_VEL_MAX > RIVER
* TOX_DEP_MAX: DEPTH SWITCH FOR VOLATILIZATION APPROACH: LAKE > TOX_DEP_MAX < RIVER
* ITOXTEMP: TEMPERATURE OVERRIDE IF ISTRAN(2)=0
* 1 - CONSTANT TEMPERATURE = TOXTEMP
* >1 - TIME VARYING TEMPERATURE SERIES FROM TSER(ITOXTEMP-1)
* TOXTEMP: CONSTANT TEMPERATURE FOR TOXICS CALCULATIONS(DEG C)
*
C43C STEPW STEPB VEL_MAX DEP_MAX ITOXTEMP TOXTEMP