§ 420.02 - General definitions.

§ 420.02 General definitions.

In addition to the definitions set forth in 40 CFR part 401, the following definitions apply to this part:

(a) The term TSS (or total suspended solids, or total suspended residue) means the value obtained by the method specified in 40 CFR 136.3.

(b) The term oil and grease (or O&G) means the value obtained by the method specified in 40 CFR 136.3.

(c) The term ammonia-N (or ammonia-nitrogen) means the value obtained by manual distillation (at pH 9.5) followed by the Nesslerization method specified in 40 CFR 136.3.

(d) The term cyanide means total cyanide and is determined by the method specified in 40 CFR 136.3.

(e) The term phenols 4AAP (or phenolic compounds) means the value obtained by the method specified in 40 CFR 136.3.

(f) The term TRC (or total residual chlorine) means the value obtained by the iodometric titration with an amperometric endpoint method specified in 40 CFR 136.3.

(g) The term chromium means total chromium and is determined by the method specified in 40 CFR 136.3.

(h) The term hexavalent chromium (or chromium VI) means the value obtained by the method specified in 40 CFR 136.3.

(i) The term copper means total copper and is determined by the method specified in 40 CFR 136.3.

(j) The term lead means total lead and is determined by the method specified in 40 CFR 136.3.

(k) The term nickel means total nickel and is determined by the method specified in 40 CFR 136.3.

(l) The term zinc means total zinc and is determined by the method specified in 40 CFR 136.3.

(m) The term benzene (or priority pollutant No. 4) means the value obtained by the standard method Number 602 specified in 44 FR 69464, 69570 (December 3, 1979).

(n) The term benzo(a)pyrene (or priority pollutant No. 73) means the value obtained by the standard method Number 610 specified in 44 FR 69464, 69570 (December 3, 1979).

(o) The term naphthalene (or priority pollutant No. 55) means the value obtained by the standard method Number 610 specified in 44 FR 69464, 69571 (December 3, 1979).

(p) The term tetrachloroethylene (or priority pollutant No. 85) means the value obtained by the standard method Number 610 specified in 44 FR 69464, 69571 (December 3, 1979).

(q) The term pH means the value obtained by the standard method specified in 40 CFR 136.3.

(r) The term non-process wastewaters means utility wastewaters (for example, water treatment residuals, boiler blowdown, and air pollution control wastewaters from heat recovery equipment); treated or untreated wastewaters from groundwater remediation systems; dewatering water for building foundations; and other wastewater streams not associated with a production process.

(s) The term nitrification means oxidation of ammonium salts to nitrites (via Nitrosomas bacteria) and the further oxidation of nitrite to nitrate via Nitrobacter bacteria. Nitrification can be accomplished in either:

(1) A single or two-stage activated sludge wastewater treatment system; or

(2) Wetlands specifically developed with a marsh/pond configuration and maintained for the express purpose of removing ammonia-N.

Indicators of nitrification capability are:

(1) Biological monitoring for ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) to determine if the nitrification is occurring; and

(2) Analysis of the nitrogen balance to determine if nitrifying bacteria reduce the amount of ammonia and increase the amount of nitrite and nitrate.

(t) The term storm water from the immediate process area means storm water that comes into contact with process equipment located outdoors, storm water collected in process area and bulk storage tank secondary containment structures, and storm water from wastewater treatment systems located outdoors, provided that it has the potential to become contaminated with process wastewater pollutants for the particular subcategory. Storm water from building roofs, plant roadways, and other storm waters that do not have the potential to become contaminated with process wastewater pollutants are not storm water from the immediate process area.

(u) The term 2,3,7,8-TCDF means 2,3,7,8-tetrachlorodibenzofuran.

[47 FR 23284, May 27, 1982, as amended at 67 FR 64260, Oct. 17, 2002]