Glossary

The erosion control world is filled with a variety of different terms and phrases that may mean one thing to a seasoned veteran but make no sense whatsoever to someone who is just starting out. ErosionControlNetwork.com has comprised a database of many of these phrases and their definitions to help you gain a better understanding of erosion control terminology. How To Use: Click a letter below to see phrases starting with that letter, or enter your word into the text box below and click the Search button. Search by Alphabet A B C D E F G H I J K L M N O P Q R S T U V W X Y Z or Search by Keyword All Search Results are Displayed Below Can't Find A Term? If there are any terms or phrases that are not in our database that you think should be, please click on the button below. We will process your request as soon as possible.

Glossary Results ------------------------------------------------------------------------------------------------------------- Daily Discharge The discharge of a pollutant measured during any 24-hour period that reasonably represents a calendar day for purposes of sampling. For pollutants with limitations expressed in units of mass, the daily discharge is calculated as the total mass of the pollutant discharged during the day. For pollutants with limitations expressed in other units of measurement (e.g., concentration) the daily discharge is calculated as the average measurement of the pollutant throughout the day (40 CFR 122.2). Daily Maximum Limit The maximum allowable discharge of pollutant during a calendar day. Where daily maximum limitations are expressed in units of mass, the daily discharge is the total mass discharged over the course of the day. Where daily maximum limitations are expressed in terms of a concentration, the daily discharge is the arithmetic average measurement of the pollutant concentration derived from all measurements taken that day. Deadman A log or block of concrete, or other material buried in a streambank that is used to tie in a revetment with cable, chain, or steel rods Deflector Structural barrier (groin, jetty) projecting into a stream to divert flow away from eroding sections of streambank Derhatch Remove an excessive thatch accumulation either (a) mechanically, as by vertical cutting, or (b) biologically, as by topdressing with soil. Development Document A report prepared during the development of an effluent limitation guideline by EPA that provides the data and methodology used to develop limitations guidelines and categorical pretreatment standards for an industrial category. Dike A structure designed either to reduce the water velocity as streamflow passes through the dike so that sediment deposition occurs instead of erosion (permeable dike), or to deflect erosive currents away from the streambank (impermeable dike); also groin, palisade, spur, jetty, or deflector Director The Regional Administrator or State Director, as the context requires, or an authorized representative. When there is no approved state program, and there is an EPA administered program, Director means the Regional Administrator. When there is an approved state program, "Director" normally means the State Director. Discharge The volume of water passing through a channel during a given time, usually measured in cubic feet per second Discharge Monitoring Report (DMR) The form used (including any subsequent additions, revisions, or modifications) to report self-monitoring results by NPDES permittees. DMRs must be used by approved states as well as by EPA. 1 2