Endpoint and test failure criteria for chronic tests

The endpoint for lethality for chronic WET testing and retesting is the NOECL. The endpoint for sublethality for routine chronic WET testing and retesting is the NOECS. Statistical analysis must be consistent with the methods described in the documents referenced in OAC 252:606-6- 29. For chronic test failure, see OAC 252:730. 252-606-6-41. WET testing frequency and trial period (a) The frequency of WET testing is once per quarter. Monitoring frequency reductions will not be granted during the first five years in which WET testing is required. (b) Monitoring frequency reductions may be granted in a second or subsequent permit renewal in accordance with OAC 252:606-6-42 after completion of a specified trial period. The minimum WET testing trial period is one year. The length of the WET testing trial period will be specified in the second or subsequent permit and will be established by DEQ based on whether and the degree to which a facility poses an increased toxicity risk due to the nature of its activities (e.g., accepting external waste streams, a history of WET test failures, or reported discharges of toxic compounds in toxic amounts). (c) If DEQ determines that an increased toxicity risk so warrants, quarterly or more frequent testing may be required for the life of the permit.