NR 111.03 Note Note: Examples of flow reduction include variable speed pumps, seasonal flow reductions, wet cooling towers, dry cooling towers, hybrid cooling towers, unit closures, or substitution for withdrawals by reuse of effluent from a nearby facility.

NR 111.03(18) (18) “Fragile species” means those species of fish and shellfish with an impingement survival rate less than 30 percent, including alewife, gizzard shad, rainbow smelt, and any other species deemed fragile by the department.

NR 111.03(19) (19) “Hydraulic zone of influence” means the portion of the source waterbody hydraulically affected by the cooling water intake structure withdrawal of water.

NR 111.03(20) (20) “Impingement” means the entrapment of any life stages of fish and shellfish on the outer part of an intake structure or against a screening device during periods of intake water withdrawal. Impingement includes those organisms collected or retained on a sieve with maximum distance in the opening of 0.56 inches and excludes those organisms that pass through the sieve. The owner or operator of a facility shall use a sieve with the same mesh size when counting entrainment as is used when counting impingement.

NR 111.03 Note Note: This definition is intended to prevent the conversion of entrainable organisms to counts of impingement or impingement mortality.

NR 111.03(21) (21) “Impingement mortality” means death as a result of impingement. “Impingement mortality” also includes the inevitable mortality of organisms due to their removal from their natural ecosystem and lack of ability to escape the cooling water intake system.

NR 111.03(22) (22) “Independent supplier” means an entity, other than the regulated facility, that owns and operates its own cooling water intake structure; directly withdraws water from surface waters of the state; and provides the cooling water to other facilities for their use, regardless of whether the entity also retains a portion of the water for its own use. “Independent supplier” does not include an entity that provides potable water to residential populations such as a public water system.

NR 111.03(23) (23) “Lake or reservoir” means any inland body of open water with some minimum surface area free of rooted vegetation and with an average hydraulic retention time of more than 7 days. “Lake or reservoir” includes a flow-through reservoir with an average hydraulic retention time of greater than 7 days.

NR 111.03 Note Note: Lakes or reservoirs might be natural waterbodies or impounded streams, surrounded by land or by land and a man-made retainer, such as a dam. Lakes or reservoirs might be fed by rivers, streams, springs, or local precipitation.

NR 111.03(24) (24) “Latent mortality” means the delayed mortality of organisms that were initially alive upon being impinged or entrained but that do not survive the delayed effects of impingement and entrainment during an extended holding period. “Delayed effects of impingement and entrainment” includes temperature change, physical stress, and chemical stress.

NR 111.03(25) (25) “Maximize” means to increase to the greatest amount, extent, or degree reasonably possible.

NR 111.03(26) (26) “Maximum design intake velocity” means the value assigned during the cooling water intake structure design to the maximum instantaneous speed at which the cooling system is capable of withdrawing water through the intake screen or inlet from a source waterbody, applied at all points between the point at which water is withdrawn from a water of the state and the first screen or other structure that has a mesh with a maximum distance in the openings of 0.56 inches, and calculated using the following equation:

where:

V = the maximum design intake velocity.

Q = the maximum volumetric flow rate based on pump capacities, excluding emergency and redundant pumps.

A = typical wetted area of the screen at Q7,10 flows.

P = screen open area percentage divided by 100.

For a facility that uses other intake designs that do not use a screen, the maximum design intake velocity shall be determined using an alternate method approved by the department.

NR 111.03(27) (27) “MGD” means millions of gallons per day.

NR 111.03(28) (28) “Minimize” means to reduce to the smallest amount, extent, or degree reasonably possible.

NR 111.03(29) (29) “Modified traveling screen” means a traveling water screen that incorporates measures protective of fish and shellfish, including all of the following:

NR 111.03(29)(a) (a) A screen with a collection bucket or an equivalent mechanism designed to minimize turbulence to aquatic life.

NR 111.03(29)(b) (b) The addition of a guard rail or barrier to prevent loss of fish from the collection system or the replacement of screen panel materials with smooth woven mesh, drilled mesh, molded mesh, or similar materials that protect fish from descaling and other abrasive injury.

NR 111.03(29)(c) (c) The continuous or near-continuous rotation of screens and operation of fish collection equipment to ensure any impinged organisms are recovered as soon as practical.

NR 111.03(29)(d) (d) A low pressure wash or gentle vacuum to remove fish prior to any high pressure spray to remove debris from the screens.

NR 111.03(29)(e) (e) A fish handling and return system with sufficient water flow to return the fish directly to the source water in a manner that does not promote predation or re-impingement of the fish or require a large vertical drop. The department may approve of fish being returned to water sources other than the original source water, taking into account any recommendations from the U.S. fish and wildlife service with respect to endangered or threatened species.

NR 111.03 Note Note: Examples of modified traveling screens include Modified Ristroph screens with a fish handling and return system, dual flow screens with smooth mesh, and rotary screens with fish returns or vacuum returns.

NR 111.03(30) (30) “Moribund” means dying or close to death.