Environmental Engineering FOURTH EDITION

List of Symbols 461

ps
PIU
PMN
POW
PPBS
PSD

Q or4

Q

Q

Qh

Qo

QP

QP

QS

QS

QW

4

R
R
R
R
R or r
R
RX
R
RACT
RCRA
RDF
ROD
r
r
r
rad
rem

S
S
S
so

SO

SIP

SIU

sd

purity of a product x, %

parameter importance units

premanufacture notification

publicly owned (wastewater) treatment works

planning, programming, and budgeting system

prevention of significant deterioration

flow rate, in m3/s or gdmin

emission rate, in g/s or kg/s

number of Ci or Bq

heat emission rate, kJ/s

influent flow rate, m3/s

pollutant flow, in mgd or m3/s (Chap. 3)

flow rate of wastewater effluent, m3/s

stream flow, in mgd or m3/s (Chap. 3)

flow rate upstream from wastewater discharge, m3/s

waste sludge flow rate, in m3/s

substrate removal velocity, in s-l

radius of influence of a gas withdrawal well, m (Chap. 13)

Rainfall factor

recovery of pollutant or collection efficiency, 5%

% of overall recovery of, SS in settling tank

hydraulic radius, in m or ft

runoff coefficient (Chap. 13)

recovery of a product x, 5%

Reynolds number

reasonable achievable control technology

Resource Conservation and Recovery Act

refuse derived fuel

record of decision (Chap. 2)

radius, in m or ft or cm

hydraulic radius in Hazen-Williams equation, m or ft

specific resistance to filtration, m/kg

unit of absorbed energy: 1 erg/g

roentgen equivalent man

rainfall storage, mm

scroll pitch, m

substrate concentration, estimated as BOD, mg/L

influent BOD, kg/h

sediment delivery ratio (dimensionless factor)

influent substrate concentration estimated as BOD, mg/L

State Implementation Plans

significant individual user