Document ID: EPA-HQ-OW-2002-0043-0145
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2003-07-22T04:00Z

STAGE
2
DISINFECTANTS
AND
DISINFECTION
BYPRODUCTS
RULE
United
States
Environmental
Protection
Agency
Office
of
Water
(
4601)
EPA
[
No.
TBD]
July
2003
Draft
This
text
is
a
draft
provided
for
public
comment.
It
has
not
had
a
final
review
for
technical
accuracy
or
adherence
to
EPA
policy;
do
not
quote
or
cite
except
as
a
public
comment.
INITIAL
DISTRIBUTION
SYSTEM
EVALUATION
Note
on
the
Stage
2
Disinfectants
and
Disinfection
Byproducts
Initial
Distribution
System
Evaluation
Guidance
Manual,
July
2003
Draft
Purpose:

The
purpose
of
this
guidance
manual,
when
finalized,
is
solely
to
provide
technical
information
for
water
systems
and
States
to
use
for
compliance
with
the
Initial
Distribution
System
Evaluation
(
IDSE),
a
component
of
the
Stage
2
Disinfectants
and
Disinfection
Byproducts
Rule
(
Stage
2
DBPR).
EPA
is
developing
the
Stage
2
DBPR
to
reduce
DBP
occurrence
peaks
in
the
distribution
system
based
on
changes
to
compliance
monitoring
provisions.
Chapter
1
of
this
manual
contains
additional
information
about
this
regulation.

This
guidance
is
not
a
substitute
for
applicable
legal
requirements,
nor
is
it
a
regulation
itself.
Thus,
it
does
not
impose
legally­
binding
requirements
on
any
party,
including
EPA,
states,
or
the
regulated
community.
Interested
parties
are
free
to
raise
questions
and
objections
to
the
guidance
and
the
appropriateness
of
using
it
in
a
particular
situation.
Although
this
manual
describes
many
methods
for
complying
with
IDSE
requirements,
the
guidance
presented
here
may
not
be
appropriate
for
all
situations,
and
alternative
approaches
may
provide
satisfactory
performance.
The
mention
of
trade
names
or
commercial
products
does
not
constitute
endorsement
or
recommendation
for
use.

Authorship:

This
manual
was
developed
under
the
direction
of
EPA's
Office
of
Water,
and
was
prepared
by
The
Cadmus
Group,
Inc.
and
Malcolm
Pirnie,
Inc.
Questions
concerning
this
document
should
be
addressed
to:

Thomas
Grubbs
and
Elin
Warn
U.
S.
Environmental
Protection
Agency
Mail
Code
4607M
1200
Pennsylvania
Avenue
NW
Washington,
DC
20460­
0001
Tel:
(
202)
564­
5262
(
Thomas
Grubbs)
(
202)
564­
1807
(
Elin
Warn)
Fax:
(
202)
564­
3767
Email:
Grubbs.
Thomas@
epamail.
epa.
gov
and
Warn.
Elin@
epamail.
epa.
gov
Request
for
comments:

EPA
is
releasing
this
manual
in
draft
form
in
order
to
solicit
public
review
and
comment.
The
Agency
would
appreciate
comments
on
the
content
and
organization
of
technical
information
presented
in
this
manual.
Please
submit
any
comments
no
later
than
90
days
after
publication
of
the
Stage
2
Disinfectants
and
Disinfection
Byproducts
Rule
proposal
in
the
Federal
Register.
Detailed
procedures
for
submitting
comments
are
stated
below.
Acknowledgements:

American
Water
Works
Association
Association
of
Metropolitan
Water
Agencies
Andrew
DeGraca
 
San
Francisco
Water
Walter
Grayman
 
W.
M.
Grayman
Consulting
Mike
Grimm
 
Oregon
Health
Department
Rich
Haberman
 
California
Department
of
Health
Services
Mike
Hotaling
 
City
of
Newport
News
Alexa
Obolensky
 
Philadelphia
Water
Department
David
Reckhow
 
University
of
Massachusetts
Amherst
Tom
Schaeffer
 
Association
of
Metropolitan
Water
Agencies
Charlotte
Smith
 
Charlotte
Smith
&
Associates
Vanessa
Speight
 
University
of
North
Carolina
Scott
Summers
 
Colorado
University
Jim
Uber
 
University
of
Cincinnati
Marguerite
Young
 
Clean
Water
Action
Procedures
for
submitting
comments:

Comments
on
this
draft
guidance
manual
should
be
submitted
to
EPA's
Water
Docket.
You
may
submit
comments
electronically,
by
mail,
or
through
hand
delivery/
courier.

·
 
To
submit
comments
using
EPA's
electronic
public
docket,
go
directly
to
EPA
Dockets
at
http://
www.
epa.
gov/
edocket,
and
follow
the
online
instructions
for
submitting
comments.
Once
in
the
system,
select
"
search,"
and
then
key
in
Docket
ID
No.
OW­
2002­
0039.

·
 
To
submit
comments
by
e­
mail,
send
comments
to
OW_
Docket@
epa.
gov,
Attention
Docket
ID
No.
OW­
2002­
0043.
If
you
send
an
e­
mail
comment
directly
to
the
Docket
without
going
through
EPA's
electronic
public
docket,
EPA's
e­
mail
system
automatically
captures
your
email
address,
which
is
included
as
part
of
the
comment
that
is
placed
in
the
official
public
docket.

·
 
To
submit
comments
on
a
disk
or
CD
ROM,
mail
it
to
the
address
identified
below.
These
electronic
submissions
will
be
accepted
in
WordPerfect
or
ASCII
file
format.
Avoid
the
use
of
special
characters
and
any
form
of
encryption.

·
 
To
submit
comments
by
mail,
send
three
copies
of
your
comments
and
any
enclosures
to:
Water
Docket,
Environmental
Protection
Agency,
Mail
Code
4101T,
1200
Pennsylvania
Ave.,
NW,
Washington,
DC,
20460,
Attention
Docket
ID
No.
OW­
2002­
0043.

·
 
To
submit
comments
by
hand
delivery
or
courier,
deliver
your
comments
to:
Water
Docket,
EPA
Docket
Center,
Environmental
Protection
Agency,
Room
B102,
1301
Constitution
Ave.,
NW,
Washington,
DC,
Attention
Docket
ID
No.
OW­
2002­
0043.
Please
identify
the
appropriate
docket
identification
number
in
the
subject
line
on
the
first
page
of
your
comment.
If
you
submit
an
electronic
comment,
please
include
your
name,
mailing
address,
and
an
e­
mail
address
or
other
contact
information
in
the
body
of
your
comment.
Also
include
this
contact
information
on
the
outside
of
any
disk
or
CD
ROM
you
submit,
and
in
any
cover
letter
accompanying
the
disk
or
CD
ROM.

For
public
commenting,
please
note
that
EPA's
policy
is
that
public
comments,
whether
submitted
electronically
or
in
paper,
will
be
made
available
for
public
viewing
in
EPA's
electronic
public
docket
as
EPA
receives
them
and
without
change,
unless
the
comment
contains
copyrighted
material,
confidential
business
information,
or
other
information
whose
disclosure
is
restricted
by
statute.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
i
Contents
Acronyms
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
viii
Definitions
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
ix
1.0
Introduction
1.1
Classifying
Systems
for
the
Purposes
of
the
IDSE
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
2
1.1.1
Determining
Source
Water
Classification
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
3
1.1.2
Determining
When
an
IDSE
Report
is
Due
to
the
State
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
3
1.1.3
Buying
or
Treating
Water
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
7
1.1.4
Number
of
"
Plants"
 
Producing
Systems
Only
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
8
1.2
Summary
of
the
Stage
2
DBPR
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
13
1.3
Overview
of
IDSE
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
17
1.3.1
Purpose
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
17
1.3.2
Applicability
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
17
1.3.3
IDSE
Options
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
17
1.3.4
IDSE
Reporting
and
Recordkeeping
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
18
1.3.5
IDSE
Standard
Monitoring
Program
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
19
1.4
Guidance
Manual
Navigation
Charts
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
22
2.0
Requirements
for
Systems
NOT
Conducting
an
IDSE
SMP
or
SSS
2.1
Introduction
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
2­
1
2.2
Criteria
for
Receiving
a
Very
Small
System
Waiver
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
2­
2
2.3
Criteria
for
Qualifying
for
the
40/
30
Certification
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
2­
3
2.4
Selecting
Stage
2B
Compliance
Monitoring
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
2­
4
2.4.1
Protocol
for
Adding
Stage
2B
Compliance
Monitoring
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
2­
5
2.4.2
Protocol
for
Dropping
Stage
1
Compliance
Monitoring
Locations
.
.
.
.
.
.
.
.
.
.
.
.
2­
6
2.5
Reporting
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
2­
7
3.0
System­
Specific
Studies
3.1
Introduction
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
1
3.2
Schedule
for
an
SSS
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
2
3.3
SSS
Using
Historical
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
2
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
ii
3.3.1
Sample
Site
and
Frequency
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
3
3.3.2
Analytical
Data
Quality
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
4
3.3.3
Historical
Sampling
Period
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
4
3.3.4
Treatment
and
Source
Conditions
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
5
3.3.5
Distribution
System
Conditions
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
6
3.4
SSS
Using
a
Water
Distribution
System
Model
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
7
3.4.1
Minimum
Model
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
9
3.4.1.1
Model
Details
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
9
3.4.1.2
Accurate
Simulation
of
Water
Consumption
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
10
3.4.1.3
Model
Calibration
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
11
3.4.2
Identifying
Preliminary
Sites
Using
Model
Results
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
12
3.4.2.1
EPS
Modeling
to
Estimate
Residence
Time,
Influence
Zones,
and
Mixing
Zones
3­
12
3.4.2.2
Preliminary
Sample
Site
Selection
to
Meet
SMP
Criteria
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
13
3.4.3
Performing
At
Least
One
Round
of
Sampling
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
15
3.5
Alternative
SSSs
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
16
3.5.1
Evaluation
of
Alternative
SSSs
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
16
3.5.2
Historical
Data
Combined
with
New
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
17
3.5.3
Historical
or
New
DBP
Data
Combined
with
a
Distribution
System
Tracer
Study
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
18
3.6
Selecting
Stage
2B
Compliance
Monitoring
Sites
Using
SSS
Results
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
20
3.6.1
Selecting
High
TTHM
and
HAA5
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
23
3.6.2
Selecting
Average
Residence
Time
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
25
3.6.3
Examples
of
Stage
2B
Site
Selection
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
26
3.7
Reporting
Results
to
the
State
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
29
4.0
Standard
Monitoring
Program
Requirements
for
100
Percent
Purchasing
Systems
4.1
Introduction
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
1
4.2
Schedule
for
Conducting
the
SMP
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
1
4.3
SMP
Monitoring
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
4
4.4
Timing
of
Sample
Collection
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
6
4.5
Sampling
Protocol
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
8
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
iii
5.0
Standard
Monitoring
Program
Requirements
for:
Producing
Surface
Water
Systems
Serving
at
Least
10,000
People
5.1
Introduction
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
1
5.2
Schedule
for
Conducting
the
SMP
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
1
5.2.1
Consecutive
Water
Systems
and
Wholesalers
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
3
5.3
Number
of
Samples
Required
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
3
5.4
Sample
Site
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
5
5.4.1
Changing
Disinfectants
During
the
SMP
Period
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
5
5.5
Timing
of
SMP
Sample
Collection
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
6
5.6
Sampling
Protocol
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
9
6.0
Standard
Monitoring
Program
Requirements
for:
Producing
Surface
Water
Systems
Serving
500
to
9,999
People
or
Producing
Ground
Water
Systems
Serving
at
Least
10,000
People
6.1
Introduction
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
1
6.2
Schedule
for
Conducting
the
SMP
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
2
6.3
SMP
Monitoring
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
3
6.4
Timing
of
Sample
Collection
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
6
6.5
Sampling
Protocol
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
9
7.0
Standard
Monitoring
Program
Requirements
for:
Producing
Surface
Water
Systems
Serving
Less
Than
500
People
or
Producing
Ground
Water
Systems
Serving
Less
Than
10,000
People
7.1
Introduction
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
1
7.2
Schedule
for
Conducting
the
SMP
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
2
7.3
Number
of
Samples
Required
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
4
7.4
Sample
Site
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
5
7.5
Timing
of
Sample
Collection
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
6
7.6
Sampling
Protocol
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
6
8.0
Standard
Monitoring
Program
Site
Selection
and
Reporting
8.1
Introduction
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
1
8.2
Description
of
SMP
Sample
Site
Types
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
2
8.2.1
Near­
Entry
Point
SMP
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
5
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
iv
8.2.1.1
Near­
Entry
Point
SMP
Sites
for
100
Percent
Purchasing
Systems
.
.
.
.
.
.
.
8­
5
8.2.1.2
Near­
Entry
Point
SMP
Sites
for
Producing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
7
8.2.2
Average
Residence
Time
SMP
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
8
8.2.3
High
TTHM
and
High
HAA5
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
8
8.3
Considerations
for
Systems
with
More
than
One
Plant
or
Entry
Point
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
9
8.3.1
100
Percent
Purchasing
Systems
with
More
Than
One
Consecutive
System
Entry
Point
8­
9
8.3.2
Producing
Systems
with
More
than
One
Plant
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
12
8.4
Data
Sources
and
Tools
for
Identifying
Preliminary
SMP
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
19
8.4.1
Maps
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
20
8.4.1.1
High
TTHM
and
High
HAA5
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
20
8.4.1.2
Average
Residence
Time
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
21
8.4.2
Distribution
System
Water
Quality
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
21
8.4.2.1
Disinfectant
Residual
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
21
8.4.2.2
DBP
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
26
8.4.3
Simulated
Distribution
System
Laboratory
Test
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
26
8.4.4
Models
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
30
8.4.4.1
High
TTHM
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
31
8.4.4.2
High
HAA5
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
32
8.4.4.3
Average
Residence
Time
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
33
8.4.5
Tracer
Studies
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
33
8.4.6
System
Operating
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
35
8.4.7
Geographic
Information
System
(
GIS)
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
36
8.5
Methodology
for
Selecting
Final
SMP
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
38
8.5.1
Identifying
Preliminary
Sites
Using
Combinations
of
Tools
and
Data
Sources
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
38
8.5.2
Selecting
Final
SMP
Sites
from
Preliminary
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
43
8.5.2.1
Selecting
High
TTHM
and
HAA5
SMP
Sites
(
All
Systems)
.
.
.
.
.
.
.
.
.
.
8­
43
8.5.2.2
Selecting
Average
Residence
Time
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
45
8.6
Stage
2B
DBPR
Site
Selection
and
IDSE
Reporting
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
45
8.6.1
100
Percent
Purchasing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
48
8.6.2
Producing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
49
8.6.3
Examples
of
Stage
2B
DBPR
Site
Selection
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
50
8.7
Reporting
Results
to
the
State
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
53
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
v
Appendices
Appendix
A
Impacts
of
an
Alternative
Population­
Based
Monitoring
Approach
Appendix
B
Formation
and
Control
of
Disinfection
Byproducts
Appendix
C
TTHM
and
HAA5
Sampling
Protocol
Appendix
D
Simulated
Distribution
System
Test
Appendix
E
IDSE
SMP
Report
for
Producing
Surface
Water
Systems
Serving
$
10,000
People
Appendix
F
IDSE
SMP
Report
for
Producing
Ground
Water
Systems
Serving
$
10,000
People
Appendix
G
IDSE
SMP
Report
for
Producing
Surface
Water
Systems
Serving
500­
9,999
People
Appendix
H
IDSE
Report
for
Producing
Ground
Water
Systems
Serving
<
10,000
People
Appendix
I
IDSE
SMP
Report
for
Producing
Surface
Water
Systems
Serving
<
500
People
Appendix
J
IDSE
SMP
Report
for
a
100
Percent
Purchasing
Surface
Water
Systems
Appendix
K
IDSE
System
Specific
Study
Using
a
Hydraulic
Model
Appendix
L
IDSE
System­
Specific
Study
Using
Historical
Data
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
vi
Tables
and
Figures
Tables
Table
1.1
Summary
of
IDSE
Reporting
Schedules
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
13
Table
1.2
Stage
2B
Plant­
based
DBPR
Monitoring
Requirements
for
Producing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
15
Table
1.3
Stage
2B
Population­
based
Compliance
Monitoring
Requirements
for
100
Percent
Purchasing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
16
Table
1.4
IDSE
SMP
Requirements
for
Producing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
20
Table
1.5
IDSE
SMP
Requirements
for
100
Percent
Purchasing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
21
Table
2.1
Compliance
Monitoring
Data
Requirements
for
the
40/
30
Certification
.
.
.
.
.
.
.
.
.
.
.
.
.
2­
4
Table
3.1
Stage
2B
Plant­
based
Compliance
Monitoring
Requirements
for
Producing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
21
Table
3.2
Stage
2B
Population­
based
Compliance
Monitoring
Requirements
for
100
Percent
Purchasing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
22
Table
3.3
Example
IDSE
Reports
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
30
Table
4.1
Consecutive
System
IDSE
Report
Schedule
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
2
Table
4.2
SMP
Sampling
Requirements
for
100
Percent
Purchasing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
5
Table
4.3
Example
of
Historic
DBP
and
Temperature
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
7
Table
5.1
SMP
Sample
Sites
for
Producing
Surface
Water
Systems
Serving
at
Least
10,000
People
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
5
Table
5.2
Example
of
Historic
DBP
and
Temperature
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
8
Table
6.1
Summary
of
SMP
Sampling
Requirements
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
4
Table
6.2
Example
of
Historic
TTHM
and
Temperature
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
8
Table
7.1
IDSE
Report
Schedule
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
2
Table
8.1
SMP
Sampling
Requirements
for
100
Percent
Purchasing
Systems1,2
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
3
Table
8.2
SMP
Sampling
Requirements
for
Producing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
4
Table
8.3
Summary
of
Characteristics
of
High
TTHM
and
High
HAA5
Areas
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
9
Table
8.4
Summary
of
GIS
Data
Storage
Capabilities
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
37
Table
8.5
Stage
2B
Compliance
Monitoring
Requirements
for
100
Percent
Purchasing
Systems1,2
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
47
Table
8.6
Summary
of
Stage
2B
Compliance
Monitoring
Requirements
for
Producing
Systems
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
48
Table
8.7
Example
IDSE
Reports
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
54
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
viii
Figures
Figure
1.1
Decision
Tree
for
Determining
IDSE
Reporting
Schedule
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
1­
5
Figure
3.1
Allowable
SSS
Historical
Sampling
Period
for
Systems
on
the
Large
System
Schedule
3­
4
Figure
3.2
SSS
Historical
Sampling
Period
for
Systems
on
the
Small
System
Schedule
.
.
.
.
.
.
3­
5
Figure
3.3
Example
of
Historical
Data
Limitations
for
System
on
Large
System
Schedule
With
a
Significant
Change
in
Distribution
System
Hydraulics
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
3­
7
Figure
4.1
Early
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
3
Figure
4.2
Late
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
3
Figure
4.3
Example
Historic
DBP
and
Temperature
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
4­
6
Figure
5.1
Large
System
Schedule
for
Conducting
the
SMP
(
Showing
Latest
Recommended
Start
Dates)
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
2
Figure
5.2
Planned
Conversion
to
Chloramines
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
6
Figure
5.3
Example
Historic
DBP
and
Temperature
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5­
7
Figure
6.1
Large
System
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
2
Figure
6.2
Small
System
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
3
Figure
6.3
Example
Historic
DBP
and
Temperature
Data
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6­
7
Figure
7.1
Large
System
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
3
Figure
7.2
Small
System
Schedule
for
Conducting
the
IDSE
SMP
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
7­
4
Figure
8.1
Data
Sources
and
Tools
for
Selecting
SMP
Sites
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
19
Figure
8.2
Conceptual
Diagram
of
GIS
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
36
Figure
8.3
Starting
Point
for
Preliminary
Site
Selection
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
8­
39
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
ix
Acronyms
CWS
Community
water
system
CT
Residual
disinfectant
concentration
(
in
mg/
L)
multiplied
by
the
contact
time
(
in
min)
 
a
measure
of
inactivation
DBP
Disinfection
byproduct
DBPR
Disinfectants
and
Disinfection
Byproducts
Rule
EPS
Extended
period
simulation
HAA
Haloacetic
acid
HAA5
The
sum
of
five
HAA
species
HPC
Heterotrophic
plate
count
ICR
Information
Collection
Rule
IDSE
Initial
distribution
system
evaluation
LRAA
Locational
running
annual
average
LT2ESWTR
Long
Term
2
Enhanced
Surface
Water
Treatment
Rule
MCAA
Monochloroacetic
acid
MCL
Maximum
contaminant
level
M­
DBP
Microbial
and
disinfection
byproduct
NPDWR
National
Primary
Drinking
Water
Regulation
NTNCWS
Nontransient
noncommunity
water
system
PWS
Public
water
system
RAA
Running
annual
average
SDS
Simulated
distribution
system
SDWA
Safe
Drinking
Water
Act
SMP
Standard
monitoring
program
SSS
System­
specific
study
SWTR
Surface
Water
Treatment
Rule
TCAA
Trichloroacetic
acid
TCR
Total
Coliform
Rule
THM
Trihalomethane
TOC
Total
organic
carbon
TNCWS
Transient
noncommunity
water
system
TTHM
Total
trihalomethanes
UV
Ultraviolet
light
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
xi
Definitions
Aquifer:
a
geological
formation
composed
of
rock,
gravel,
sand,
or
other
porous
material
that
yields
water
to
wells
or
springs.

Best
professional
judgement:
using
knowledge
and
experience
to
make
a
decision
on
an
issue
that
does
not
have
a
clear
direction
or
answer,
or
deciding
to
take
an
alternative
path
to
the
one
recommended
based
on
knowledge
and
experience.

Booster
disinfection:
the
practice
of
adding
disinfectant
in
the
distribution
system
to
increase
disinfectant
residual
concentration.

Combined
distribution
system:
the
interconnected
distribution
system
consisting
of
the
distribution
systems
of
wholesale
systems
and
of
the
consecutive
systems
that
receive
finished
water
from
those
wholesale
system(
s).
40
CFR
141.2
Community
water
system:
a
public
water
system
which
serves
at
least
15
service
connections
used
by
year­
round
residents
or
regularly
serves
at
least
25
year­
round
residents.
40
CFR
141.2
Conductivity:
a
measurement
of
the
ability
of
a
solution
to
carry
an
electrical
current.

Consecutive
system:
a
public
water
system
that
buys
or
otherwise
receives
some
or
all
of
its
finished
water
from
one
or
more
wholesale
systems
for
at
least
60
days
per
year.
40
CFR
141.2
Consecutive
system
entry
point:
a
location
at
which
finished
water
is
delivered
at
least
60
days
per
year
from
a
wholesale
system
to
a
consecutive
system.
40
CFR
141.2
Controlling
month:
the
month
of
historical
peak
DBP
levels,
or,
in
the
absence
of
DBP
data,
the
month
of
highest
water
temperature
by
which
the
IDSE
sampling
schedule
is
set.

Disinfectant:
any
oxidant,
including
but
not
limited
to
chlorine,
chlorine
dioxide,
chloramines,
and
ozone
added
to
water
in
any
part
of
the
treatment
or
distribution
process,
that
is
intended
to
kill
or
inactivate
pathogenic
microorganisms.
40
CFR
141.2
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
xii
Disinfectant
residual
concentration:
the
concentration
of
disinfectant
that
is
maintained
in
a
distribution
system.
Disinfectant
could
be
free
chlorine
(
the
sum
of
the
concentrations
of
hypochlorous
acid
(
HOCl)
and
hypochlorite
acid
(
OCl­))
or
combined
chlorine
(
chloramines).
It
is
used
in
Surface
Water
Treatment
Rule
as
a
measure
for
determining
CT.

Disinfection:
a
process
which
inactivates
pathogenic
organisms
in
water
by
chemical
oxidants
or
equivalent
agents.
40
CFR
141.2
Disinfection
byproduct
(
DBP):
compound
formed
from
the
reaction
of
a
disinfectant
with
organic
and
inorganic
compounds
in
the
source
or
treated
water
during
the
disinfection
process.

Dual
Sample
set:
TTHM
and
HAA5
samples
that
are
taken
at
the
same
time
and
location
for
the
purpose
of
conducting
an
IDSE
evaluation
and
determining
compliance
with
the
TTHM
and
HAA5
MCLs.

Finished
Water:
water
that
has
been
introduced
into
the
distribution
system
of
a
public
water
system
and
is
intended
for
distribution
without
further
treatment,
except
that
necessary
to
maintain
water
quality
(
such
as
booster
disinfection).
40
CFR
141.2
Ground
water
under
the
direct
influence
of
surface
water
(
GWUDI):
any
water
beneath
the
surface
of
the
ground
with
(
1)
significant
occurrence
of
insects
or
other
macroorganisms,
algae,
or
largediameter
pathogens
such
as
Giardia
lamblia,
or
(
2)
significant
and
relatively
rapid
shifts
in
water
characteristics
such
as
turbidity,
temperature,
conductivity,
or
pH
which
closely
correlate
to
climatological
or
surface
water
conditions.
Direct
influence
must
be
determined
for
individual
sources
in
accordance
with
criteria
established
by
the
State.
The
State
determination
of
direct
influence
may
be
based
on
site­
specific
measurements
of
water
quality
and/
or
documentation
of
well
construction
characteristics
and
geology
with
field
evaluation.
40
CFR
141.2
Haloacetic
acid
(
HAA):
one
of
the
family
of
organic
compounds
named
as
a
derivative
of
acetic
acid,
wherein
one
to
three
hydrogen
atoms
in
the
methyl
group
in
acetic
acid
are
each
substituted
by
a
halogen
atom
(
namely,
chlorine
and
bromine)
in
the
molecular
structure.

Haloacetic
acids
(
five)
(
HAA5):
the
sum
of
the
concentrations
in
milligrams
per
liter
of
the
haloacetic
acid
compounds
(
monochloroacetic
acid,
dichloroacetic
acid,
trichloroacetic
acid,
monobromoacetic
acid,
and
dibromoacetic
acid),
rounded
to
two
significant
figures
after
addition.
40
CFR
141.2
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
xiii
Heterotrophic
plate
count
(
HPC):
a
procedure
for
estimating
the
number
of
heterotrophic
bacteria
in
water,
measured
as
the
number
of
colony
forming
units
per
100
mL.

Influence
zone:
the
portions
of
the
distribution
system
supplied
with
water
from
a
particular
source
of
supply.

Locational
running
annual
average
(
LRAA):
the
average
of
samples
taken
at
a
particular
monitoring
site
during
the
previous
four
calendar
quarters.

Maximum
contaminant
level
(
MCL):
the
maximum
permissable
level
of
a
contaminant
in
water
which
is
delivered
to
any
user
of
a
public
water
system.
40
CFR
141.2
Maximum
contaminant
level
goal
(
MCLG):
the
maximum
level
of
a
contaminant
in
drinking
water
at
which
no
known
or
anticipated
adverse
effect
on
the
health
of
persons
would
occur,
and
which
allows
an
adequate
margin
of
safety.
Maximum
contaminant
level
goals
are
non­
enforceable
health
goals.
40
CFR
141.2
Mixing
Zone:
an
area
in
the
distribution
system
where
water
flowing
from
two
or
more
different
sources
blend.

Monitoring
site:
the
location
where
samples
are
collected.

Nontransient
noncommunity
water
system
(
NTNCWS):
a
public
water
system
that
is
not
a
community
water
system
and
that
regularly
serves
at
least
25
of
the
same
persons
over
6
months
per
year.
40
CFR
141.2
Noncommunity
water
system:
a
public
water
system
that
is
not
a
community
water
system.
40
CFR
141.2
Public
water
system
(
PWS):
a
system
for
the
provision
to
the
public
of
piped
water
for
human
consumption,
if
such
system
has
at
least
fifteen
service
connections
or
regularly
serves
an
average
of
at
least
twenty­
five
individuals
daily
at
least
60
days
out
of
the
year.
Such
term
includes
(
1)
any
collection,
treatment,
storage,
and
distribution
facilities
under
control
of
the
operator
of
such
system
and
used
primarily
in
connection
with
such
system,
and
(
2)
any
collection
or
pretreatment
storage
facilities
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
xiv
not
under
such
control
which
are
used
primarily
in
connection
with
such
system.
A
public
water
system
is
either
a
"
community
water
system"
or
a
"
noncommunity
water
system."
40
CFR
141.2
Residence
time:
the
time
period
lasting
from
when
the
water
is
treated
to
a
particular
point
in
the
distribution
system.
Also
referred
to
as
water
age.

Residual
disinfection:
also
referred
to
as
"
secondary
disinfection."
The
process
whereby
a
disinfectant
(
typically
CL
or
CLM)
is
added
to
finished
water
in
order
to
maintain
a
disinfection
residual
in
the
distribution
system.

Running
annual
average:
the
average
of
monthly
or
quarterly
averages
of
all
samples
taken
throughout
the
distribution
system,
as
averaged
over
the
preceding
four
quarters.

Service
connection:
as
used
in
the
definition
of
public
water
system,
does
not
include
a
connection
to
a
system
that
delivers
water
by
a
constructed
conveyance
other
than
a
pipe
if:
(
1)
The
water
is
used
exclusively
for
purposes
other
than
residential
uses
(
consisting
of
drinking,
bathing,
and
cooking,
or
other
similar
uses);
(
2)
The
State
determines
that
alternative
water
to
achieve
the
equivalent
level
of
public
health
protection
provided
by
the
applicable
national
primary
drinking
water
regulation
is
provided
for
residential
or
similar
uses
for
drinking
and
cooking;
or
(
3)
The
State
determines
that
the
water
provided
for
residential
or
similar
uses
for
drinking,
cooking,
and
bathing
is
centrally
treated
or
treated
at
the
point
of
entry
by
the
provider,
a
pass­
through
entity,
or
the
user
to
achieve
the
equivalent
level
of
protection
provided
by
the
applicable
national
primary
drinking
water
regulations.
(
From
the
National
Primary
Drinking
Water
Regulations,
40
CFR
Ch.
1,
7/
1/
00
Edition.)

Stage
2A:
the
period
beginning
[
3
years
after
rule
promulgation]
until
the
dates
specified
for
compliance
with
Stage
2B,
during
which
systems
must
comply
with
Stage
2A
MCLs.

Stage
2B:
the
period
beginning
[
6
years
after
rule
promulgation]
for
systems
serving
at
least
10,000
people;
[
8.5
years
after
rule
promulgation]
for
systems
serving
fewer
than
10,000
people
that
are
required
to
do
Cryptosporidium
monitoring
under
the
Long
Term
2
Enhanced
Surface
Water
Treatment
Rule
(
LT2ESWTR);
[
7.5
years
after
rule
promulgation]
for
all
other
systems
serving
fewer
than
10,000
people,
during
which
systems
must
comply
with
Stage
2B
MCLs.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
xv
State:
the
agency
of
the
State
or
Tribal
government
which
has
jurisdiction
over
public
water
systems.
During
any
period
when
a
State
or
Tribal
government
does
not
have
primary
enforcement
responsibility
pursuant
to
section
1413
of
the
Act,
the
term
"
State"
means
the
Regional
Administrator,
U.
S.
Environmental
Protection
Agency.
40
CFR
141.2
Subpart
H
systems:
public
water
systems
using
surface
water
or
ground
water
under
the
direct
influence
of
surface
water
as
a
source
that
are
subject
to
the
requirements
of
40
CFR
141.2
(
h).
40
CFR
141.2
Surface
water:
all
water
which
is
open
to
the
atmosphere
and
subject
to
surface
runoff.
40
CFR
141.2
Total
trihalomethanes
(
TTHM):
the
sum
of
the
concentration
in
milligrams
per
liter
of
the
trihalomethane
compounds
(
trichloromethane,
[
chloroform],
dibromochloromethane,
bromodichloromethane,
and
tribromomethane
[
bromoform]),
rounded
to
two
significant
figures.
40
CFR
141.2
Total
chlorine
residual:
the
sum
of
combined
chlorine
(
chloramine)
and
free
available
chlorine
residual.

Tracer
study:
a
procedure
for
estimating
hydraulic
properties
of
the
distribution
system,
such
as
residence
time.
Where
more
than
one
water
source
feeds
the
distribution
system,
tracer
studies
can
be
used
to
determine
the
zone
of
influence
of
each
source.

Trihalomethane
(
THM):
one
of
the
family
of
organic
compounds
named
as
derivatives
of
methane,
wherein
three
of
the
four
hydrogen
atoms
in
methane
are
each
substituted
by
a
halogen
atom
in
the
molecular
structure.
40
CFR
141.2
Water
distribution
system
model:
a
computer
program
that
can
simulate
the
hydraulic,
and
in
some
cases,
water
quality
behavior
of
water
in
a
distribution
system.

Wholesale
system:
a
public
water
system
that
treats
source
water
and
then
sells
or
otherwise
delivers
finished
water
to
another
public
water
system
for
at
least
60
days
per
year.
Delivery
may
be
through
a
direct
connection
or
through
the
distribution
system
of
another
consecutive
system.
40
CFR
141.2
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
1
A
CWS
is
public
water
system
that
has
at
least
15
service
connections
used
by
year­
round
residents
or
regularly
serves
at
least
25
year­
round
residents
(
40
CFR
141.2).

2
A
NTNCWS
is
a
public
water
system
that
has
at
least
15
service
connections
or
regularly
serves
an
average
of
at
least
25
of
the
same
individuals
for
at
least
6
months
per
year
(
40
CFR
141.2).

3
Throughout
this
document,
the
terms
"
State"
or
"
States"
are
used
to
refer
to
all
types
of
primacy
agencies,
including
U.
S.
Territories,
Indian
Tribes,
and
EPA
Regions.

July
2003­
Proposal
Draft
All
Systems
1­
1
Subsequent
chapters
of
this
manual
apply
to
different
IDSE
options
and
system
sizes
and
types.
1.0
Introduction
Initial
Distribution
System
Evaluations
(
IDSEs),
required
by
the
Stage
2
Disinfectants
and
Disinfection
Byproducts
Rule
(
DBPR),
are
studies
conducted
by
water
systems
to
identify
compliance
monitoring
sites
that
represent
high
disinfection
byproduct
(
DBP)
levels
in
distribution
systems
(
40
CFR
141.600).
IDSEs
are
based
on
either
1
year
of
monitoring
or
other
system­
specific
data
that
provide
equivalent
or
better
information
than
monitoring.
Systems
serving
fewer
than
500
people
can
receive
waivers
from
IDSE
requirements,
and
systems
that
demonstrate
historically
low
distribution
system
DBP
concentrations
may
not
have
to
perform
an
IDSE.

The
Stage
2
DBPR
(
also
referred
to
as
"
the
rule")
applies
to
all
community
water
systems1
(
CWSs)
and
nontransient
noncommunity
water
systems2
(
NTNCWSs)
that
add
a
primary
or
residual
disinfect
other
than
ultraviolet
light
(
UV),
or
deliver
water
that
has
been
treated
with
a
primary
or
residual
disinfectant
other
than
UV
(
40
CFR
141.620(
b)).
IDSEs
are
a
key
part
of
the
rule
and
the
focus
of
this
guidance
manual.
The
purposes
of
this
manual
are
two­
fold
 
to
provide
guidance
to
systems
so
that
they
can
meet
IDSE
requirements
and
provide
guidance
to
States3
in
evaluating
the
adequacy
of
IDSEs.

This
introductory
chapter
is
organized
as
follows:

1.1
Classifying
Systems
for
the
Purposes
of
the
IDSE
1.2
Summary
of
the
Stage
2
DBPR
1.3
Overview
of
IDSE
Requirements
1.4
Guidance
Manual
Navigation
Charts
Chapters
2
through
8
of
this
manual
describe
IDSE
requirements
for
different
IDSE
options
and
system
sizes
and
types.

Systems
will
not
need
to
read
every
chapter
of
this
manual
 
the
manual
is
organized
such
that
systems
can
refer
to
one
or
more
stand­
alone
chapters
depending
on
their
systems'
characteristics
and
IDSE
option.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
2
The
manual
contains
the
following
features
to
guide
systems
to
the
appropriate
chapters:

°
The
worksheet
on
page
1­
13
will
help
systems
classify
themselves
for
the
purposes
of
determining
their
IDSE
requirements
(
all
systems
should
fill
out
this
worksheet).

°
The
flow
chart
and
examples
in
section
1.1
will
help
systems
determine
their
IDSE
schedule.

°
The
Guidance
Manual
Navigation
charts
in
section
1.4
are
provided
to
help
systems
determine
which
IDSE
option
they
can
use
to
meet
requirements
and
which
chapter(
s)
provides
more
information
on
each
option.

°
Additional
flow
charts
at
the
end
of
Chapters
4
through
7
are
for
those
systems
that
conduct
monitoring
for
an
IDSE.

°
Notes
on
the
bottom
of
every
page
indicate
the
type
and
size
of
system
to
which
that
chapter
applies.

1.1
Classifying
Systems
for
the
Purposes
of
the
IDSE
Requirements
for
the
IDSE
(
as
well
as
requirements
for
Stage
2
DBPR
compliance
monitoring)
differ
by
system
size
and
type
(
40
CFR
141.602).
For
example,
systems
using
only
ground
water
will
have
different
monitoring
requirements
than
systems
using
surface
water.
Small
systems
may
have
different
IDSE
schedules
than
large
systems.
Before
reading
the
rest
of
this
manual,
it
is
important
for
systems
to
first
determine
their
classification
so
that
they
will
understand
which
rule
requirements
apply
to
them.

In
general,
there
are
four
main
system
characteristics
that
drive
IDSE
requirements:

°
Source
water
classification
(
surface
vs.
ground)

°
Buying
and
selling
relationships
with
other
systems
(
consecutive
vs.
wholesale)

°
Size
(
population
served)

°
Number
of
treatment
plants
Source
water
classification
is
discussed
in
section
1.1.1.
Section
1.1.2
describes
how
to
determine
when
the
IDSE
report
is
due
to
the
State.
This
is
important
in
the
classification
process
because
the
IDSE
schedule
determines
which
operating
year
must
be
reviewed
to
determine
further
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
3
rule
requirements
(
for
systems
that
buy
at
least
some
of
their
water).
Section
1.1.3
provides
additional
rule
clarifications
for
systems
that
buy
some
or
all
of
their
water.
Section
1.1.4
follows
with
guidance
for
determining
the
number
of
plants
in
a
water
system
(
e.
g.,
if
you
buy
finished
water
from
another
water
system,
the
rule
may
require
that
interconnection
to
be
considered
a
"
plant").
A
worksheet
is
provided
at
the
end
of
this
section
to
help
systems
determine
their
classifications.

1.1.1
Determining
Source
Water
Classification
For
the
purposes
of
the
IDSE
and
Stage
2
DBPR,
systems
must
determine
if
they
are
a
surface
or
ground
water
system.

°
Surface
water
systems
are
the
same
as
subpart
H
systems
 
they
use
surface
water
or
ground
water
under
the
direct
influence
of
surface
water
(
GWUDI).
Surface
water
systems
include
those
that
treat
surface
water
(
or
GWUDI)
themselves
or
purchase
finished
surface
water
from
other
systems.
Surface
water
systems
include
all
mixed
systems
that
have
both
surface
and
ground
water
sources.

°
Ground
water
systems
are
those
systems
that
use
only
disinfected
ground
water
(
or
purchased
disinfected
ground
water).

1.1.2
Determining
When
an
IDSE
Report
is
Due
to
the
State
For
the
purposes
of
this
guidance
manual,
the
early
schedule
means
that
systems
must
submit
their
IDSE
report
no
later
than
[
2
years
after
rule
promulgation],
while
the
late
schedule
means
that
systems
must
submit
their
report
no
later
than
[
4
years
after
rule
promulgation].
Table
1.1
shows
which
systems
must
conform
to
each
schedule
type.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
4
Table
1.1
Summary
of
IDSE
Reporting
Schedules1
Schedule
Type
Report
Due
Date
Applicable
Systems
Early
schedule
[
2
years
after
rule
promulgation]
Systems
serving
at
least
10,000
people
Systems
serving
less
than
10,000
people
that
are
part
of
a
combined
distribution
system
with
at
least
one
system
serving
10,000
or
more
people
Late
schedule
[
4
years
after
rule
promulgation]
Systems
serving
less
than
10,000
people
that
are
not
part
of
a
combined
distribution
system
with
at
least
one
system
serving
10,000
or
more
people
1(
40
CFR
141.600(
c))

As
indicated
in
the
table,
an
IDSE
report
schedule
is
based
on
the
population
served
by
the
largest
system
in
the
combined
distribution
system.
Note
that
the
schedule
is
based
on
the
largest
population
served
by
a
single
system
(
not
the
sum
of
all
system
populations)
in
the
combined
distribution
system.
The
Stage
2
DBPR
defines
the
following
terms
for
systems
buying
and
selling
finished
water
(
40
CFR
141.2):

Consecutive
system
­
public
water
system
that
buys
or
otherwise
receives
some
or
all
of
their
finished
water
from
one
or
more
systems
for
at
least
60
days
per
year.

Wholesale
systems
­
public
water
system
that
treats
source
water
and
then
sells
or
otherwise
delivers
finished
water
to
another
public
water
system
for
at
least
60
days
per
year.
Delivery
may
be
through
a
direct
connection
or
through
the
distribution
system
of
one
or
more
consecutive
systems.

Combined
distribution
system
­
the
totality
of
the
distribution
systems
of
wholesale
systems
and
of
the
consecutive
systems
that
receive
finished
water
from
those
wholesale
systems.

Delivery
of
water
from
a
wholesale
system
can
be
through
a
direct
connection(
s)
or
through
the
distribution
system
of
another
system.
For
example,
in
a
situation
where
system
A
buys
water
from
system
B
who
buys
all
their
water
from
system
C,
all
three
systems
are
considered
to
be
in
the
same
combined
distribution
system.

To
determine
which
systems
are
included
in
a
combined
distribution
system,
include
only
those
that
buy
for
at
least
60
days
per
year
during
year
2004.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
5
The
flow
chart
in
Figure
1.1
can
be
used
to
determine
the
IDSE
report
schedule
required
for
systems.
Examples
1.1
through
1.3
show
how
the
guidance
is
applied
in
specific
situations.
Systems
that
are
still
unclear
on
their
IDSE
report
schedule
after
reading
this
section
should
contact
their
State
for
guidance.
A
worksheet
for
systems
to
complete
is
provided
at
the
end
of
the
section
that
also
assists
in
determining
report
schedule.

EPA
recommends
that
systems
share
information
about
their
IDSE
report
schedule
with
all
wholesale
purchasers.
Coordination
with
purchasing
systems
is
not
required,
but
is
strongly
recommended.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
6
No
Does
your
system
serve
>
10,000
people?
Early
Schedule
Did
your
system
purchase
water
from
or
sell
water
to
another
system
for
more
than
60
days
in
2004?
Yes
Yes
You
are
part
of
a
combined
distribution
system
No
Late
Schedule
Is
there
a
system
that
serves
>
10,000
people
in
the
combined
distribution
system?
No
Yes
Figure
1.1
Decision
Tree
for
Determining
IDSE
Reporting
Schedule
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
8
Bloomville
Water
System
Population
Served
=
3,000
Red
Hill
Water
System
Population
Served
=
8,000
Elm
Grove
Water
System
Population
Served
=
12,000
Apple
Burg
System
Population
Served
=
5,000
Greenville
System
Population
Served
=
14,000
Your
City
System
Population
Served
=
7,500
***
Examples
for
Determining
IDSE
Report
Schedule***

Example
1.1
 
One
Seller
with
Two
Buyers
Red
Hill
water
system
sells
water
to
both
Elm
Grove
and
Bloomville
systems
year­
round.

Bloomville,
Red
Hill,
and
Elm
Grove
are
all
part
of
one
combined
distribution
system.
Because
Elm
Grove
serves
greater
than
10,000
people,
all
three
systems
are
on
the
early
schedule.

Example
1.2
 
Systems
with
Temporary
Sources
Your
City
purchases
all
of
its
water
from
nearby
Apple
Burg.
A
pple
Burg
purchased
water
on
an
emergency
basis
from
Greenville
for
less
th
an
60
days
in
2004.
Because
Greenville
is
considered
a
temporary
(
not
a
p
ermanent)
source
for
Apple
Burg,
it
is
not
considered
to
be
part
of
the
s
ame
combined
distribution
system
as
Apple
Burg
and
Your
City.
T
herefore,
Your
City
and
Apple
Burg
are
on
the
late
schedule.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
10
Newington
System
Population
Served
=
4,000
Seaside
System
Population
Served
=
16,000
Dellwood
System
Population
Served
=
8,000
Groveland
System
Population
Served
=
3,000
Example
1.3
 
Systems
with
Permanent,
Seasonal
Sources
Seaside
system
sells
water
for
approximately
90
consecutive
days
in
the
summer
to
Dellwood.
Dellwood
buys
the
remainder
of
its
water
from
Newington.
Groveland
buys
a
portion
of
its
water
year­
round
from
Dellwood.

All
four
systems
shown
are
part
of
the
same
combined
distribution
system.
Because
the
largest
system
serves
16,000
people,
all
systems
are
on
the
early
schedule.

1.1.3
Buying
or
Treating
Water
IDSE
requirements
differ
between
those
system
that
treat
some
or
all
of
their
water
and
those
that
buy
all
of
their
finished
water.
Because
the
use
of
seasonal
or
emergency
water
can
differ
from
year
to
year,
the
Stage
2
DBPR
requires
that
systems
evaluate
operating
data
from
the
year
2004
if
they
are
on
the
early
IDSE
schedule
and
from
year
2006
if
on
the
late
IDSE
schedule
(
40
CFR
141.602(
d)).

Throughout
this
guidance
manual,
the
terms
"
100
percent
purchasing
systems"
and
"
producing
systems"
are
used
to
differentiate
between
the
two
system
types
when
describing
IDSE
requirements.

°
100
percent
purchasing
systems
­
consecutive
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
systems
year­
round.
Systems
that
buy
all
of
their
finished
water,
but
also
use
booster
disinfection,
are
still
considered
a
100
percent
purchasing
systems.

°
Producing
systems
­
systems
that
do
not
purchase
100
percent
of
their
finished
water
from
other
systems
year­
round
(
i.
e.,
they
have
one
or
more
non­
purchased
sources
and
produce
some
or
all
of
their
own
finished
water).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
4
A
consecutive
system
entry
point
is
a
site
at
which
finished
water
is
delivered
from
a
wholesale
system
to
a
consecutive
system
that
buys
some
or
all
of
its
water,
at
least
60
days
per
year.
To
be
considered
a
"
plant,"
water
must
be
delivered
for
60
consecutive
days
per
year.

July
2003­
Proposal
Draft
All
Systems
1­
11
1.1.4
Number
of
"
Plants"
 
Producing
Systems
Only
If
you
are
a
100
percent
purchasing
system,
you
can
skip
this
section
and
go
directly
to
next
section
(
1.2
Summary
of
the
Stage
2
DBPR).

Monitoring
requirements
of
the
Stage
2
DBPR
depend
on
the
number
of
"
plants"
in
a
system
for
those
systems
that
produce
some
or
all
of
their
own
water.
The
rule
specifies
that
consecutive
system
entry
points4
receiving
water
treated
by
a
disinfectant
other
than
UV,
for
at
least
60
consecutive
days
a
year,
must
be
considered
as
a
plant
(
40
CFR
141.601(
d)).
For
the
purposes
of
guidance
the
following
should
also
be
considered
as
a
"
plant":

°
A
facility
treating
a
surface
water
source
in
the
system.

°
A
facility
treating
(
at
minimum,
adding
a
disinfectant,
not
including
UV)
a
ground
water
source
in
the
system.

Note,
a
system
may
be
defined
as
a
consecutive
system
(
receiving
water
for
at
least
60
days
per
year)
while
the
consecutive
entry
point
is
not
considered
as
a
plant
because
they
do
not
receive
water
for
60
consecutive
days.

The
rule
allows
States
to
consider
multiple
entry
points
or
treatment
facilities
as
one
"
plant"
in
the
following
situations
(
40
CFR
141.601(
d)):

°
Multiple
Wells
Drawing
from
the
Same
Aquifer.
With
State
approval,
systems
with
multiple
wells
drawing
from
a
single
aquifer
may
consider
those
wells
as
one
plant.

°
Multiple
Consecutive
Entry
Points
Delivering
Water
from
One
Wholesaler.
Systems
with
multiple
consecutive
entry
points
from
the
same
wholesale
system
may
consider
those
entry
points
one
plant,
with
State
approval.
In
these
cases,
the
system
must
demonstrate
that
factors
such
as
relative
locations
of
entry
points,
residence
times,
sources,
and
the
presence
of
treatment
(
such
as
corrosion
control
or
booster
disinfection)
are
similar
and
will
not
have
a
significant
effect
on
TTHM
and
HAA5
formation
between
the
entry
points.

The
following
are
instances
in
which
treatment
facilities
and
entry
points
should
not
considered
a
plant.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
12
°
Booster
disinfection
or
other
satellite
treatment
facilities
that
may
add
disinfection
to
finished
water.

°
Individuals
wells
that
feed
into
one
entry
point
or
treatment
facility
(
only
the
one
entry
point
would
be
considered
a
plant).

°
Consecutive
entry
points
that
are
used
for
less
than
60
consecutive
days
per
year
(
e.
g.,
emergency
connections).

°
Interconnections
that
deliver
untreated
water.

Examples
1.4
through
1.6
show
how
these
guidelines
can
be
used
to
determine
the
number
of
plants
for
the
purposes
of
an
IDSE.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
13
Purchased
surface
water
Well
#
2
(
Chlorinated)
Well
#
1
(
Chlorinated)
Well
#
3
(
Chlorinated)

Wholesaler,
Ground
Water
Source
Well
#
1
Well
#
2
Chlorine
Feed
***
Examples
for
Determining
Number
of
Plants***

Example
1.4
 
Multiple
Wells
and
Purchasing
Treated
Water
A
system
purchases
treated
surface
water
year­
round
through
one
entry
point,
and
has
three
wells.
Chlorine
is
added
at
each
well
site.
The
State
determined
that
two
of
the
wells
draw
from
the
same
aquifer
and
that
the
third
well
draws
from
a
different
aquifer.

Total
plants:
3
(
one
for
the
purchased
water
entry
point,
the
second
for
the
two
wells
drawing
from
the
same
aquifer,
and
the
third
for
the
well
drawing
from
another
aquifer).

Example
1.5
 
Multiple
Consecutive
Entry
Points
and
Multiple
Wells
A
system
purchases
treated
ground
water
from
one
wholesaler
through
five
entry
points
and
has
two
wells.
The
State
has
approved
multiple
consecutive
entry
points
to
be
considered
as
one
plant.
The
two
wells
feed
into
one
pumphouse
where
chlorine
is
added;
this
is
considered
one
treatment
plant.

Total
plants:
2
(
one
plant
for
the
consecutive
entry
points
and
one
ground
water
plant)
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
14
***
Examples
for
Determining
Number
of
Plants
(
continued)***

Example
1.6
 
Connections
Not
Used
Year­
Round
Your
City's
system
purchases
disinfected
ground
water
from
City
A
year­
round
and
has
an
emergency
connection
with
City
B.
In
the
summer
of
2004,
City
A's
water
supply
was
low,
so
Your
City's
system
had
to
use
City
B
intermittently
from
July
to
September.
Your
City
reviewed
its
purchasing
records
from
year
2004
and
determined
that
you
received
water
from
City
B
for
72
days
that
year,
but
at
most,
only
45
days
were
consecutive.

Total
plants:
1
(
City
A)
(
Although
the
City
B
connection
is
considered
a
consecutive
system
entry
point,
it
is
not
considered
a
plant
since
Your
City's
system
did
not
receive
water
for
60
consecutive
days
in
year
2004).

1.1.5
System
Classification
Worksheet
A
system
classification
worksheet
is
provided
on
the
next
page
to
help
systems
determine
their
IDSE
schedule
and
buying/
selling
relationships
for
the
purposes
of
determining
IDSE
requirements
and
navigating
this
guidance
manual.
Before
using
this
manual,
it
is
very
important
that
all
systems
complete
this
worksheet.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
15
System
Classification
Worksheet
Determine
System
Size
and
Schedule
1.
What
is
the
population
served
by
your
water
system?

>
10,000
º
You
are
a
Large
System
on
the
Late
Schedule.
Go
to
#
3.

<
10,000
º
You
are
a
Small
System.
Go
to
#
2.

2.
Small
systems
(
serving
<
10,000):
Did
your
system
buy
or
sell
finished
water
for
at
least
60
days
in
the
year
2004?

No
º
You
are
on
the
Late
Schedule.

Yes
º
Is
there
a
system
that
serves
over
10,000
people
in
your
combined
distribution
system?

No
º
You
are
on
the
Late
Schedule.

Yes
º
You
are
on
the
Early
Schedule.

Determine
Consecutive
System
Status
3.
Did
you
buy
finished
water
for
at
least
60
days
in
2004
(
if
on
the
Early
Schedule)
or
2006
(
if
on
the
Late
Schedule)?

No
º
You
are
a
Producing
System
(
you
are
done
with
this
worksheet).

Yes
º
You
are
a
Consecutive
System.
Go
to
#
4.

4.
Consecutive
systems:
Did
you
buy
all
of
your
finished
water
in
2004
(
if
on
the
Early
Schedule)
or
2006
(
if
on
the
Late
Schedule)?

No
º
You
are
a
Producing
System.
Go
to
#
5.

Yes
º
You
are
a
100
Percent
Purchaser
(
you
are
done
with
this
worksheet).

5.
Consecutive,
producing
systems:
If
you
purchase
any
finished
water
from
a
wholesale
system
for
at
least
60
consecutive
days
during
2004
(
if
on
the
Early
Schedule)
or
2006
(
if
on
the
Late
Schedule),
you
must
treat
these
entry
points
as
"
plants"
for
the
purposes
of
determining
IDSE
and
Stage
2B
monitoring
requirements.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
5
U.
S.
Environmental
Protection
Agency.
2000.
Stage
2
M­
DBP
Agreement
in
Principle.
Microbial/
Disinfection
Byproducts
(
M­
DBP)
Federal
Advisory
Committee.
Signed
September
12,
2000.
Federal
Register
65(
251):
83015­
83024.

6
Actual
compliance
dates
to
be
provided
in
future
drafts.

7
Although
MCLs
are
Stated
in
milligrams
per
liter
(
mg/
L)
in
the
Stage
2
DBPR
rule
language,
they
are
presented
as
:
g/
L
to
be
consistent
with
terminology
in
the
rest
of
this
guidance
manual.

July
2003­
Proposal
Draft
All
Systems
1­
16
1.2
Summary
of
the
Stage
2
DBPR
(
40
CFR
141,
Subpart
Q,
Appendix
A,
141.600,
and
141.626)

The
Stage
2
DBPR
applies
to
all
CWSs
and
NTNCWSs
that
add
a
primary
or
residual
disinfectant
other
than
UV,
or
deliver
water
that
has
been
treated
with
a
disinfectant
other
than
UV.
The
compliance
determination
and
schedule,
compliance
monitoring,
and
significant
excursion
requirements
for
the
Stage
2
DBPR
are
discussed
below.
Section
1.3
provides
a
more
detailed
description
of
IDSE
provisions.

Purpose
As
Stated
in
the
Stage
2
Microbial
and
DBP
Agreement
in
Principle,
"
The
Stage
2
DBPR
is
designed
to
reduce
DBP
occurrence
peaks
in
the
distribution
system
based
on
changes
to
compliance
monitoring
provisions.
Compliance
monitoring
will
be
preceded
by
an
IDSE
study
to
select
sitespecific
optimal
sample
points
for
capturing
peaks."
5
Compliance
Determination
and
Schedule
Compliance
determination
for
the
Stage
2
DBPR
is
based
on
a
locational
running
annual
average
(
LRAA)
of
total
trihalomethanes
(
TTHM)
and
five
haloacetic
acids
(
HAA5)
concentrations.
Compliance
must
be
met
at
each
monitoring
location,
instead
of
system­
wide
using
the
running
annual
average
(
RAA)
used
under
the
Stage
1
DBPR.

The
rule
will
be
implemented
in
two
stages:

Stage
2A:
Starting
[
3
years
after
rule
promulgation],
6
all
systems
must
comply
with
TTHM/
HAA5
maximum
contaminant
levels
(
MCLs)
of
120/
100
micrograms
per
liter
(
µ
g/
L)
7,
measured
as
LRAAs
at
each
Stage
1
DBPR
compliance
monitoring
site
and
continue
to
comply
with
the
Stage
1
DBPR
MCLs
of
80/
60
µ
g/
L
measured
as
RAAs.

Stage
2B:
Beginning
in
[
6
years
after
rule
promulgation],
systems
serving
at
least
10,000
people
must
comply
with
TTHM/
HAA5
MCLs
of
80/
60
µ
g/
L
measured
as
LRAAs
at
the
monitoring
sites
identified
in
the
IDSE
report.
For
systems
serving
fewer
than
10,000
people
that
are
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
17
required
to
do
Cryptosporidium
monitoring
under
the
Long
Term
2
Enhanced
Surface
Water
Treatment
Rule
(
LT2ESWTR),
compliance
with
the
80/
60
µ
g/
L
MCLs
measured
as
LRAAs
will
begin
[
8.5
years
after
rule
promulgation].
For
all
other
systems
serving
fewer
than
10,000
people,
compliance
with
the
80/
60
µ
g/
L
MCLs
measured
as
LRAAs
will
begin
[
7.5
years
after
rule
promulgation].
States
may
grant
up
to
a
2­
year
extension
if
capital
improvements
are
required
by
a
system
to
comply
with
the
MCLs.

Compliance
Monitoring
Systems
will
continue
to
monitor
at
their
Stage
1
DBPR
compliance
monitoring
locations
during
Stage
2A.
For
Stage
2B,
EPA
has
developed
different
compliance
monitoring
approaches
depending
on
the
system's
buying
and
selling
relationships
with
other
systems:

°
A
plant­
based
approach
for
producing
systems
that
is
dependent
on
population
served,
source
water,
AND
the
number
of
plants
in
a
system
(
as
with
Stage
1
DBPR
compliance
monitoring)
and
applies
to
systems
that
produce
some
or
all
of
their
own
finished
water.
For
the
purpose
of
the
Stage
2
DBPR,
a
plant
can
be
either
a
treatment
plant
(
that
provides,
at
a
minimum,
disinfection
using
a
disinfectant
other
than
UV)
or
a
consecutive
system
entry
point
that
operates
for
at
least
60
consecutive
days
per
year.

°
A
population­
based
approach
for
100
percent
purchasing
systems
that
is
dependent
on
population
served
and
source
water
and
applies
to
only
those
systems
that
purchase
100
percent
of
their
finished
water
from
other
systems.

Tables
1.2
and
1.3
summarize
Stage
2B
compliance
monitoring
requirements
for
producing
systems
(
plant­
based
approach)
and
100
percent
purchasing
systems
(
population­
based
approach),
respectively.

Changes
in
the
total
number
of
samples
collected
per
year
from
the
Stage
1
to
the
Stage
2
DBPR
will
be
minor
for
most
producing
systems.
The
type
of
samples,
however,
will
change
for
most
systems.
For
100
percent
purchasing
systems,
the
change
in
monitoring
from
the
Stage
1
to
the
Stage
2
DBPR
will
vary
from
system
to
system
depending
on
the
number
of
plants.

Significant
Excursion
Evaluations
Because
Stage
2
DBPR
MCL
compliance
is
based
on
an
annual
average
of
DBP
measurements
at
a
given
location,
a
system
could
from
time
to
time
have
DBP
levels
significantly
higher
than
the
MCL
while
still
being
in
compliance.
This
is
because
high
concentrations
could
be
averaged
with
lower
concentrations
at
a
given
location.
The
Stage
2
DBPR
requires
States
to
develop
a
procedure
for
identifying
significant
DBP
excursions
as
a
special
primacy
condition.
If
a
significant
excursion
occurs,
a
system
must
conduct
a
significant
excursion
evaluation
and
discuss
the
evaluation
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
18
The
number
of
compliance
monitoring
sites
presented
in
Table
1.2
are
per
plant.
with
the
State
no
later
than
the
next
sanitary
survey.
Significant
excursion
evaluations
are
not
covered
in
this
manual.
EPA
is
developing
a
separate
guidance
manual
to
address
significant
excursion
evaluations.

Table
1.2
Stage
2B
Plant­
based
Compliance
Monitoring
Requirements
for
Producing
Systems1,2
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
location
type)
per
Plant4
Total
Number
of
Sites
per
Plant
Monitoring
Frequency5
Stage
1
Average
Residence
Time
Site
Highest
TTHM
Highest
HAA5
Surface
Water
Systems6
<
500
­
1
1
27
Every
365
days
500
­
9,999
­
1
1
2
Every
90
days
>
10,000
1
2
1
4
Every
90
days
Ground
Water
Systems
<
500
­
1
1
27
Every
365
days
500
­
9,999
­
1
1
2
Every
365
days
>
10,000
­
1
1
2
Every
90
days
1
(
40
CFR
141.605
(
a))

2
For
the
purpose
of
this
guidance
manual,
producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
3
Population
served
is
typically
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
4
For
the
purposes
of
the
Stage
2
DBPR
compliance
monitoring,
a
consecutive
system
entry
point
that
operates
for
at
least
60
consecutive
days
per
year
must
be
considered
a
plant
(
40
CFR
141.601(
d)).
5
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location,
unless
otherwise
noted.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
6
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
7
Dual
sample
sets
are
not
required
at
both
the
high
TTHM
and
the
high
HAA5
site
 
if
the
highest
TTHM
and
HAA5
levels
occur
at
a
different
location,
then
only
one
sample
is
collected
at
each
location.
If
they
occur
at
the
same
location,
then
a
dual
sample
set
is
collected
at
that
location.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
20
The
number
of
compliance
monitoring
sites
presented
in
Table
1.3
are
per
system.
Table
1.3
Stage
2B
Population­
based
Compliance
Monitoring
Requirements
for
100
Percent
Purchasing
Systems1,2
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
location
type)
per
System
Total
Number
of
Sites
per
System
Monitoring
Frequency4
Stage
1
Average
Residence
Time
Site
Highest
TTHM
Highest
HAA5
Surface
Water
Systems5
<
500
­
1
1
26
Every
365
days
500
­
4,999
­
1
1
26
Every
90
days
5,000
­
9,999
­
1
1
2
Every
90
days
10,000
­
24,999
1
2
1
4
Every
90
days
25,000
­
49,999
1
3
2
6
Every
90
days
50,000
­
99,999
2
4
2
8
Every
90
days
100,000
­
499,999
3
6
3
12
Every
90
days
500,000
­
1,499,999
4
8
4
16
Every
90
days
1.5
million
­
<
5
million
5
10
5
20
Every
90
days
>
5
million
6
12
6
24
Every
90
days
Ground
Water
Systems
<
500
­
1
1
26
Every
365
days
500
­
9,999
­
1
1
2
Every
365
days
10,000
­
99,999
1
2
1
4
Every
90
days
100,000
­
499,999
1
3
2
6
Every
90
days
>
500,000
2
4
2
8
Every
90
days
1
(
40
CFR
141.605
(
e))

2
For
the
purpose
of
this
guidance
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.
3
Population
served
is
typically
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
4
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location,
unless
otherwise
noted.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
5
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
6
Dual
sample
sets
are
not
required
at
both
the
high
TTHM
and
the
high
HAA5
site
 
if
the
highest
TTHM
and
HAA5
levels
occur
at
a
different
location,
then
only
one
sample
is
collected
at
each
location.
If
they
occur
at
the
same
location,
then
a
dual
sample
set
is
collected
at
that
location.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
21
1.3
Overview
of
IDSE
Requirements
(
40
CFR
141.600­
604)

This
section
provides
a
brief
overview
of
IDSE
requirements.
Other
sections
of
this
manual
that
provide
more
detailed
information
and
guidance
are
referenced.

1.3.1
Purpose
The
Stage
2
DBPR
requires
monitoring
at
sites
that
represent
the
areas
of
high
DBP
levels
in
the
distribution
system,
which
differs
from
Stage
1
DBPR
site
requirements.
The
existing
Stage
1
DBPR
monitoring
site
requirements
are
based
on
residence
time
only.
Other
factors
contribute
to
DBP
formation,
particularly
for
HAAs,
that
can
cause
higher
DBP
concentrations
in
areas
not
represented
by
Stage
1
sites.
Additionally,
for
surface
water
systems,
the
Stage
1
DBPR
requires
only
one
of
four
monitoring
sites
per
plant
at
a
maximum
residence
time
location
and
three
sites
at
average
residence
time
locations.
Generally,
high
DBPs
occur
in
areas
of
higher
residence
time
and
a
well­
maintained
residual
disinfectant.

The
purpose
of
the
IDSE
is
to
identify
areas
in
the
distribution
system
with
representative
high
DBP
concentrations.
The
purpose
of
the
IDSE
is
not
to
identify
the
peak
daily
or
hourly
DBP
concentrations
that
occur
in
a
distribution
system,
but
instead,
to
find
areas
with
routinely
higher
DBP
concentrations
than
other
locations.
As
discussed
later
in
this
manual,
systems
will
select
compliance
monitoring
sites
based
on
annual
averages
of
DBP
data
at
selected
sites,
not
the
results
of
individual
sampling
events.

1.3.2
Applicability
IDSE
requirements
of
the
Stage
2
DBPR
apply
to
all
CWSs
that
add
a
primary
or
residual
disinfectant
other
than
UV
to
their
water
and
consecutive
CWSs
that
deliver
water
that
has
been
treated
with
a
primary
or
residual
disinfectant
other
than
UV.
The
same
requirements
apply
to
NTNCWSs
except
those
that
serve
fewer
than
10,000
people
 
these
systems
are
not
required
to
perform
an
IDSE.

1.3.3
IDSE
Options
This
section
provides
a
brief
summary
of
waivers
and
certifications
for
systems
not
performing
an
IDSE,
as
well
as
options
available
for
systems
that
must
perform
an
IDSE.
The
first
guidance
manual
navigation
chart
in
section
1.6
directs
readers
to
other
chapters
of
this
manual
for
guidance
on
determining
the
appropriate
IDSE
option
for
a
specific
system.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
22
The
systems
that
do
not
have
to
perform
an
IDSE
are
described
below.

°
NTNCWSs
serving
fewer
than
10,000
people
do
not
have
to
meet
the
IDSE
provisions
of
the
Stage
2
DBPR
and
do
not
have
to
perform
an
IDSE.

°
States
can
grant
very
small
system
waivers
to
systems
serving
fewer
than
500
people
if
the
State
determines
that
the
Stage
1
DBPR
compliance
monitoring
site
represents
both
high
TTHM
and
high
HAA5
concentrations.

°
Systems
can
qualify
for
the
40/
30
certification.
Systems
that
can
certify
all
TTHM
and
HAA5
compliance
data
are
less
than
or
equal
to
40
µ
g/
L
for
TTHM
and
30
µ
g/
L
for
HAA5
are
not
required
to
perform
an
IDSE.

Systems
not
performing
an
IDSE
may
still
need
to
add
a
monitoring
site
to
meet
the
requirements
of
the
Stage
2B
(
selecting
Stage
2B
monitoring
sites
are
addressed
in
other
chapters
of
this
manual
­
see
section1.6
for
the
guidance
manual
navigation
chart
for
IDSE
options).

For
systems
performing
an
IDSE,
there
are
two
options:

°
Conduct
a
System­
Specific
Study
(
SSS).
The
purpose
of
an
SSS
is
to
evaluate
DBP
concentrations
throughout
the
distribution
system
using
an
existing
data
source
or
combinations
of
data
sources.
Possible
data
sources
include:
historical
DBP
and
disinfectant
residual
data,
water
distribution
system
modeling,
and
tracer
studies.

°
Complete
the
Standard
Monitoring
Program
(
SMP).
The
SMP
entails
1
year
of
distribution
system
monitoring.
The
minimum
number
of
sample
locations
required
and
sampling
frequency
depend
on
system
characteristics
such
as
size,
source
water
type,
and
number
of
plants
(
for
some
systems).

The
SMP
option
for
an
IDSE
is
the
default
 
if
a
system
does
not
qualify
for
a
waiver
and
does
not
meet
the
requirements
for
or
choose
to
complete
an
SSS,
they
must
conduct
monitoring
under
the
SMP.

1.3.4
IDSE
Reporting
and
Recordkeeping
IDSE
reporting
requirements
depend
on
the
IDSE
option
used
by
the
system.
The
following
options
require
an
IDSE
report
to
be
submitted
to
the
State:

°
40/
30
certification
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
8EPA
is
considering
an
alternative
to
the
Stage
2
DBPR
whereby
the
population­
based
approach
would
apply
to
ALL
systems
for
IDSE
and
Stage
2B
monitoring.
Appendix
A
describes
the
possible
impacts
on
systems
and
implications
for
this
guidance
manual
of
this
alternative
July
2003­
Proposal
Draft
All
Systems
1­
23
°
SSS
°
SMP
Systems
receiving
a
very
small
system
waiver
do
not
need
to
submit
an
IDSE
report.

Minimum
report
contents
for
each
option
are
addressed
later
in
this
manual
(
see
section1.6
for
guidance
manual
navigation
charts
for
IDSE
options).
The
schedule
for
submitting
reports
to
the
State
does
not
depend
on
the
IDSE
option,
but
is
based
on
system
size
and
buying
and
selling
relationships
with
other
systems
as
follows:

°
Large
systems
(
serving
at
least
10,000
people)
or
systems
with
a
large
system
in
their
combined
distribution
system
must
submit
their
report
[
2
years
after
rule
promulgation].

°
All
other
systems
must
submit
their
report
[
4
years
after
rule
promulgation].

Section
1.4
provides
detailed
guidance
for
identifying
systems
in
a
combined
distribution
system
and
determining
an
IDSE
report
due
date.

Systems
must
keep
a
complete
copy
of
the
submitted
IDSE
report
for
10
years
after
the
initial
submission
date.
The
reports
must
also
be
available
for
review
by
the
State
or
public
during
this
time.

1.3.5
IDSE
Standard
Monitoring
Program
Requirements
As
with
Stage
2B
compliance
monitoring,
there
are
two
regulatory
approaches
to
an
IDSE
SMP8:

°
A
plant­
based
approach
for
producing
systems
that
is
dependent
on
source
water
type,
population
served,
AND
number
of
plants
in
a
system
(
consistent
with
Stage
1
DBPR
compliance
monitoring).
This
approach
applies
to
systems
that
produce
some
or
all
of
their
own
finished
water.

°
A
population­
based
approach
for
100
percent
purchasing
systems
that
is
dependent
on
source
water
type,
population
served,
and
applies
to
only
those
systems
that
purchase
100
percent
of
their
finished
water
from
other
systems.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
24
The
number
of
SMP
sites
presented
in
Table
1.4
are
per
plant.
Tables
1.4
and
1.5
summarize
an
IDSE
SMP
compliance
requirements
for
producing
systems
and
100
percent
purchasing
systems,
respectively.
Note
that
the
TTHM
and
HAA5
results
from
the
IDSE
SMP
are
not
to
be
used
in
compliance
calculations
for
the
Stage
1
or
Stage
2A.
Table
1.4
IDSE
SMP
Requirements
for
Producing
Systems1,2
System
Size
(
Population
Served3)
Residual
Disinfectant
Number
of
Distribution
System
Sites
(
by
location
type)
per
Plant
Total
Number
of
Sites
per
Plant
Monitoring
Frequency4
Near
Entry
Point
Average
Residence
Time
High
TTHM
High
HAA5
Surface
Water
Systems5
<
500
Chlorine
or
Chloramines
­
­
1
1
2
Every
180
days
500
­
9,999
Chlorine
or
Chloramines
­
­
1
1
2
Every
90
days
>
10,000
Chlorine
1
2
3
2
8
Every
60
days
Chloramines
2
2
2
2
8
Ground
Water
Systems
<
10,000
Chlorine
or
Chloramines
­
­
1
1
2
Every
180
days
>
10,000
Chlorine
or
Chloramines
­
­
1
1
2
Every
90
days
1
(
40
CFR
141.602(
a))
2
For
the
purpose
of
this
guidance
manual,
producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
3
Population
served
is
usually
a
system's
residential
population.
It
does
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
4
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
5
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
25
The
number
of
SMP
sites
presented
in
Table
1.5
are
per
system.
Table
1.5
IDSE
SMP
Requirements
for
100
Percent
Purchasing
Systems1,2
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
location
type)
per
System
Total
Number
of
Sites
per
System
Monitoring
Frequency
for
the
1­
year
IDSE
Period5
Near
Entry
Point4
Average
Residence
Time
High
TTHM
High
HAA5
Surface
Water
Systems6
<
500
­
­
1
1
2
Every
180
days
500
­
4,999
­
­
1
1
2
Every
90
days
5,000
­
9,999
­
1
2
1
4
Every
90
days
10,000
­
24,999
1
2
3
2
8
Every
60
days
25,000
­
49,999
2
3
4
3
12
Every
60
days
50,000
­
99,999
3
4
5
4
16
Every
60
days
100,000
­
499,999
4
6
8
6
24
Every
60
days
500,000
­
<
1.5
million
6
8
10
8
32
Every
60
days
1.5
million
­
<
5
million
8
10
12
10
40
Every
60
days
>
5
million
10
12
14
12
48
Every
60
days
Ground
Water
Systems
<
500
­
­
1
1
2
Every
180
days
500
­
9,999
­
­
1
1
2
Every
90
days
10,000
­
99,999
1
1
2
2
6
Every
90
days
100,000
­
499,999
1
1
3
3
8
Every
90
days
>
500,000
2
2
4
4
12
Every
90
days
1
(
40
CFR
141.602
(
b))
2
For
the
purposes
of
this
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.
3
Population
served
is
usually
a
system's
residential
population.
It
does
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.

4
See
section
8.2
for
requirements
when
the
number
of
entry
points
in
a
system
is
different
from
the
number
of
required
near­
entry
point
sites
in
this
table.
5
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
6
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
26
1.4
Guidance
Manual
Navigation
Charts
The
guidance
manual
navigation
flow
charts
in
this
section
will
help
guide
readers
to
the
appropriate
section
or
chapter(
s).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
27
Could
your
system
be
eligible
for
a
very
small
system
waiver
or
a
40/
30
certification?
Yes
Verify
eligibility.

Go
to
Chapter
2
-
Requirements
for
Systems
NOT
Performing
an
IDSE
SMP
or
SSS
No
Understand
SMP
Requirements.

Continue
to
Guidance
Manual
Navigation
for
SMPs.
Does
your
system
have
extensive
water
quality
or
hydraulic
data?
Yes
Determine
if
data
can
be
used
for
an
SSS.

Go
to
Chapter
3
-
System
Specific
Studies
No
Are
you
a
NTNCWS
serving
<
10,000
people?
Yes
No
Go
to
Chapter
2
-
Requirements
for
Systems
NOT
Performing
an
IDSE
SMP
or
SSS
Eligible?
Comply
with
requirements
in
Chapter
2
Comply
with
requirements
in
Chapter
3
Conducting
an
SSS?
Yes
Yes
No
No
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003­
Proposal
Draft
All
Systems
1­
28
­
Surface
water
systems
serving
500
 
9,999
people
­
Ground
water
systems
serving
>
10,000
people
­
Surface
water
systems
serving
>
10,000
people
Go
to
Chapter
5
­
SMP
Requirements
for
Producing
Systems:
SW
serving
>
10,000
people
Go
to
Chapter
6
­
SMP
Requirements
for
Producing
Systems:
SW
serving
500
 
9,999
people
and
GW
serving
>
10,000
people
Go
to
Chapter
7
­
SMP
Requirements
for
Producing
Systems:
SW
serving
<
500
people
and
GW
serving
<
10,000
people
Go
to
Chapter
8
 
SMP
Site
Selection
and
Reporting
Are
you
a
100
Percent
Purchasing
System?

No
Yes
Go
to
Chapter
4
 
SMP
Requirements
for
100
Percent
Purchasing
Systems
Find
the
source
water
type
and
size
of
your
Producing
System
­
Surface
water
systems
serving
<
500
people
­
Ground
water
systems
serving
<
10,000
people
1
1
Use
System
Classification
Worksheet
to
determine
whether
you
are
a
100%
purchasing
or
producing
system
and
whether
you
are
a
ground
or
surface
water
system.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
1
For
the
purposes
of
this
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.
Producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
See
Chapter
1
for
additional
guidance
on
classifying
systems.

July
2003
­
Proposal
Draft
All
Systems
2­
1
2.0
Requirements
for
Systems
NOT
Conducting
an
IDSE
SMP
or
SSS
2.1
Introduction
Systems
are
NOT
required
to
conduct
the
IDSE
system­
specific
study
(
SSS)
or
standard
monitoring
program
(
SMP)
if
(
40
CFR
141.600(
b)):

1)
They
are
a
nontransient
noncommunity
water
system
(
NTNCWS)
serving
less
than
10,000
people.

2)
They
receive
a
very
small
system
waiver
from
the
State.
States
can
grant
very
small
system
waivers
to
systems
serving
less
than
500
people
if
they
determine
that
the
Stage
1
Disinfectants
and
Disinfection
Byproducts
Rule
(
DBPR)
compliance
monitoring
site
represents
both
high
total
trihalomethane
(
TTHM)
and
high
five
haloacetic
acids
(
HAA5)
concentrations.

3)
They
qualify
for
the
40/
30
certification.
Any
system
can
"
opt
out"
of
the
IDSE
if
they
certify
that
all
compliance
monitoring
data
are
less
than
or
equal
to
40
µ
g/
L
for
TTHM
and
30
µ
g/
L
for
HAA5.

Even
if
they
do
not
perform
the
IDSE,
systems
that
purchase
100
percent
of
their
finished
water1
may
have
to
add
or
be
able
to
remove
compliance
monitoring
sites
from
their
existing
Stage
1
DBPR
compliance
locations
to
meet
the
requirements
of
the
Stage
2
DBPR.

This
chapter
addresses
requirements
for
those
systems
not
conducting
an
IDSE
SSS
or
SMP
and
is
organized
as
follows:

2.2
Criteria
for
Receiving
a
Very
Small
System
Waiver
2.3
Criteria
for
Qualifying
for
the
40/
30
Certification
2.4
Selecting
Stage
2B
Compliance
Monitoring
Sites
2.5
Reporting
Requirements
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
2
This
rule
of
thumb
is
based
on
analysis
of
TTHM
and
HAA5
data
collected
under
the
Information
Collection
Rule
(
ICR).

July
2003
­
Proposal
Draft
All
Systems
2­
2
2.2
Criteria
for
Receiving
a
Very
Small
System
Waiver
Systems
serving
fewer
than
500
people
are
eligible
for
an
IDSE
waiver
if
the
State
determines
that
the
Stage
1
DBPR
monitoring
site
(
the
location
of
maximum
residence
time
in
the
distribution
system)
represents
the
highest
concentration
for
both
TTHM
and
HAA5
(
40
CFR
141.603).
This
will
often
be
the
case
 
both
TTHM
and
HAA5
tend
to
continue
to
form
in
drinking
water
as
long
as
disinfectant
residuals
and
DBP
precursors
are
present.
Unlike
TTHM,
however,
HAA5
is
known
to
biodegrade
when
disinfectant
residuals
are
low
(
see
Appendix
B
for
additional
information
of
HAA5
formation
and
biodegredation).
Below
are
some
system
conditions
that
indicate
that
the
highest
TTHM
and
HAA5
concentrations
may
not
occur
at
the
same
location:

°
Inability
to
maintain
a
disinfectant
residual
in
all
parts
of
the
system.
Areas
with
very
low
or
no
disinfectant
residual
can
have
long
residence
times
and
may
have
some
biological
activity.
These
areas
may
have
high
TTHM
concentrations
due
to
long
residence
time,
but
have
less­
than­
maximum
HAA5
concentrations
due
to
biodegradation
in
the
distribution
system.

°
High
levels
of
heterotrophic
bacteria
(
if
data
are
available).
Elevated
levels
of
heterotrophic
bacteria
in
the
distribution
system
(
especially
if
they
occur
repeatedly)
may
reflect
environmental
conditions
that
promote
biofilm
growth
and,
thus,
have
the
potential
for
HAA5
biodegradation.

°
TTHM
concentration
much
greater
than
HAA5
concentration
at
the
Stage
1
DBPR
monitoring
site
(
possibly
indicating
degradation
of
HAA5
in
the
sample
location
area).
As
a
rule
of
thumb,
EPA
recommends
that
systems
consider
selecting
a
different
monitoring
site
to
represent
high
HAA5
if
their
Stage
1
DBPR
TTHM
data
are,
on
average,
more
than
4
times
greater
than
Stage
1
DBPR
HAA5
data.
2
These
guidelines
are
not
all­
inclusive
 
TTHM
and
HAA5
formation
depends
on
many
system­
specific
factors.

States
should
notify
systems
serving
less
than
500
people
as
to
their
waiver
status.
If
the
highest
TTHM
and
HAA5
concentrations
do
not
occur
at
the
same
location
and
the
State
does
not
grant
the
waiver,
systems
must
perform
an
IDSE.
See
Chapter
4
for
SMP
requirements
for
100
percent
purchasing
systems
and
Chapter
7
for
SMP
requirements
for
producing
systems
serving
less
than
500
people.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
2­
3
2.3
Criteria
for
Qualifying
for
the
40/
30
Certification
Systems
demonstrating
low
historic
TTHM
and
HAA5
distribution
system
concentrations
in
accordance
with
the
Stage
2
DBPR
requirements
may
qualify
for
the
40/
30
certification.
Systems
must
meet
the
following
to
qualify
(
40
CFR
141.603(
b)):

°
All
individual
TTHM
compliance
data
must
be
less
than
or
equal
to
40
µ
g/
L
and
all
individual
HAA5
compliance
data
must
be
less
than
or
equal
to
30
µ
g/
L
during
the
periods
specified
in
Table
2.1.

°
No
TTHM
or
HAA5
monitoring
violations
during
the
period
specified
in
Table
2.1
°
All
monitoring
data
must
have
been
analyzed
by
a
certified
laboratory
(
per
Stage
1
DBPR
compliance
monitoring
requirements).

Consecutive
systems
that
did
not
take
the
number
of
samples
required
of
its
size
and
source
water
type
under
the
Stage
1
DBPR,
are
not
eligible
for
the
40/
30
certification
(
40
CFR
141.601(
a)).
The
Stage
1
DBPR
allowed
the
State
to
allocate
sample
sites
across
a
combined
distribution
system
at
their
discretion.
As
a
result,
some
systems
may
have
few
or
no
sample
sites
and
thus
insufficient
data
to
support
a
40/
30
certification.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
2­
4
Table
2.1
Compliance
Monitoring
Data
Requirements
for
the
40/
30
Certification1
Source
Water
Type
Population
Served2
Regulation
and
Monitoring
Period3
Surface
water4
>
10,000
people
Stage
1
DBPR
compliance
data
from
January
2002
to
December
2003
<
10,000
people
that
have
a
system
serving
>
10,000
people
in
their
combined
distribution
system5
Stage
1
DBPR
compliance
data
collected
in
2004
<
10,000
people
that
do
not
have
a
system
serving
>
10,000
people
in
their
combined
distribution
system5
Stage
1
DBPR
compliance
data
from
January
2004
to
December
2005
Ground
water
>
10,000
people
TTHM
Rule
compliance
data
from
2003
and
Stage
1
DBPR
compliance
collected
in
2004
<
10,000
people
that
have
a
system
serving
>
10,000
people
in
their
combined
distribution
system5
Stage
1
DBPR
compliance
data
collected
in
2004
<
10,000
people
that
do
not
have
a
system
serving
>
10,000
people
in
their
combined
distribution
system5
Stage
1
DBPR
compliance
data
from
January
2004
to
December
2005
1
40
CFR
141.603(
b).
2
Population
served
is
usually
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
3
All
data
must
have
been
analyzed
by
a
certified
laboratory
and
done
by
approved
methods
(
as
required
by
the
Stage
1
DBPR).
In
addition,
systems
must
not
have
had
any
TTHM
or
HAA5
monitoring
violations
during
the
period
specified.
4
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
5
A
combined
distribution
system
is
the
totality
of
the
distribution
system
of
all
wholesale
systems
and
the
consecutive
systems
that
receive
finished
water
from
the
wholesale
systems.
See
section
1.1
for
guidance
in
identifying
the
largest
system
in
a
combined
distribution
system.

2.4
Selecting
Stage
2B
Compliance
Monitoring
Sites
NTNCWSs
Serving
<
10,000
People
and
CWSs
Receiving
Very
Small
System
Waivers
(
40
CFR
141.601(
a))

All
NTNCWSs
serving
less
than
10,000
people
and
CWSs
receiving
a
very
small
system
waiver
must
continue
to
use
their
Stage
1
DBPR
monitoring
location
for
the
Stage
2B.
In
addition,
samples
must
be
collected
during
the
same
month
as
used
for
compliance
under
the
Stage
1
DBPR.

Systems
Qualifying
for
the
40/
30
Certification
(
40
CFR
141.605(
c))
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
2­
5
Producing
systems
that
qualify
for
the
40/
30
certification
may
continue
using
their
Stage
1
DBPR
monitoring
locations
or
may
select
different
Stage
2B
monitoring
sites
that
better
represent
high
TTHM
and
HAA5
concentrations.
New
sites
should
represent
water
with
long
residence
times
and
detectable
disinfectant
residual
concentrations.
Systems
must
always
retain
the
Stage
1
DBPR
monitoring
locations
with
the
highest
TTHM
and
HAA5
annual
average
concentrations.
If
there
are
site
changes,
the
rationale
must
be
included
in
the
IDSE
report
(
see
section
2.5
for
reporting
requirements
for
systems
that
qualify
for
the
40/
30
certification).

For
100
percent
purchasing
systems
that
qualify
for
the
40/
30
certification,
there
may
be
a
change
in
the
required
number
of
monitoring
sites
as
these
systems
move
from
a
plant­
based
(
under
Stage
1
DBPR)
to
a
population­
based
monitoring
approach
under
the
Stage
2
DBPR.
These
systems
may
be
required
to
select
more
Stage
2B
monitoring
locations
if
more
sites
are
required
under
Stage
2B
than
were
required
under
Stage
1.
Similarly,
if
fewer
monitoring
sites
are
required
under
Stage
2B
compared
to
Stage
1,
then
systems
are
permitted
to
"
drop"
monitoring
locations.

Sections
2.4.1
and
2.4.2
describe
the
protocol
for
adding
and
dropping
sites,
respectively.
Examples
2.1
and
2.2
that
follow
illustrate
this
protocol.

2.4.1
Protocol
for
Adding
Stage
2B
Compliance
Monitoring
Sites
When
additional
Stage
2B
sites
are
required,
they
should
be
selected
in
the
following
order:
maximum
residence
time
site
followed
by
an
average
residence
time
site.
If
a
system
is
required
to
add
more
than
two
sites,
additional
sites
should
be
added
in
the
same
order.
Chapter
8
provides
guidance
for
identifying
maximum
and
average
residence
time
locations.
100%
Purchasing
Systems
Add
Stage
2B
sites
in
the
following
order:

1)
Maximum
residence
time
2)
Average
residence
time
Repeat
if
more
than
two
sites
are
required.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
2­
6
2.4.2
Protocol
for
Dropping
Stage
1
Compliance
Monitoring
Locations
When
fewer
sites
are
required
for
Stage
2B
than
are
required
for
Stage
1
DBPR,
compliance
monitoring
locations
may
be
dropped
based
on
Stage
1
DBPR
monitoring
results.
Sites
should
be
dropped
according
to
the
lowest
annual
average
TTHM
concentration
(
provided
these
locations
are
not
the
highest
HAA5
sites).

***
Examples
for
Adding
and
Dropping
Compliance
Monitoring
Sites***

Example
2.1
 
Adding
Sites
A
100
percent
purchasing
surface
water
system
serving
85,000
people
can
qualify
for
the
40/
30
certification.
This
system
has
one
consecutive
system
entry
point
and
was
required
to
have
4
compliance
monitoring
sites
for
the
Stage
1
DBPR.
For
the
Stage
2
DBPR,
this
system
must
have
8
compliance
monitoring
sites.
This
system
must
ADD
4
sites
to
its
existing
Stage
1
DBPR
monitoring
sites
to
meet
the
Stage
2
DBPR
requirements.
The
4
sites
must
be
as
follows:
2
maximum
residence
time
sites
and
2
average
residence
time
sites.

Example
2.2
 
Dropping
Sites
A
100
percent
purchasing
surface
water
system
serving
12,000
people
can
qualify
for
the
40/
30
certification.
This
system
has
2
consecutive
system
entry
points
from
2
different
wholesale
systems
and
was
required
to
have
8
sites
under
the
Stage
1
DBPR.
For
the
Stage
2
DBPR,
this
system
is
required
to
have
a
total
of
6
compliance
monitoring
sites.
Thus,
this
system
can
DROP
2
sites
from
its
existing
Stage
1
DBPR
compliance
monitoring
sites
to
meet
the
Stage
2
DBPR
requirements.
The
2
sites
must
be
as
follows:
2
sites
with
lowest
annual
average
TTHM
concentration
(
as
long
as
these
sites
do
not
have
the
maximum
annual
average
HAA5
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
2­
7
2.5
Reporting
Requirements
The
following
systems
DO
NOT
have
to
submit
IDSE
reports
to
their
States:

1)
NTNCWS
serving
less
than
10,000
people.

2)
Systems
receiving
a
very
small
system
waiver
from
the
State.

Systems
qualifying
for
the
40/
30
certification,
however,
MUST
complete
an
IDSE
report
and
submit
it
to
their
State
(
40
CFR
141.604(
b)).
See
section
1.1
to
determine
if
your
system
is
on
the
Early
Schedule
and
must
submit
your
report
by
[
2
years
after
rule
promulgation]
or
the
Late
Schedule
and
must
submit
your
report
by
[
4
years
after
rule
promulgation].

At
minimum,
the
IDSE
report
for
the
40/
30
certification
must
include
(
40
CFR
141.604(
b)
and
(
c)):

°
All
TTHM
and
HAA5
analytical
results
from
compliance
monitoring
used
to
qualify
for
the
40/
30
certification
°
A
schematic
of
the
distribution
system
with
results,
location,
and
date
of
all
compliance
samples
noted
°
Proposed
month(
s)
of
monitoring
for
Stage
2B
 
schedule
must
include
peak
historical
month
for
TTHM
and
HAA5
concentrations,
unless
the
State
approves
another
month
(
40
CFR
141.605(
f))

°
For
systems
that
decide
NOT
to
use
one
or
more
of
their
Stage
1
DBPR
sites
for
Stage
2B
compliance
monitoring,
the
location(
s)
of
and
rationale
for
selecting
the
new
site(
s)

°
For
100
percent
purchasing
systems
that
must
add
a
site,
the
location
of
additional
Stage
2B
compliance
monitoring
sites
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
1
The
SSS
must
provide
equivalent
or
superior
data
for
selection
of
Stage
2B
sites
compared
to
selection
of
sites
resulting
from
an
SMP
(
40
CFR
141.603).
3.0
System­
Specific
Studies
3.1
Introduction
A
System­
Specific
Study
(
SSS),
like
the
Standard
Monitoring
Program
(
SMP)
described
in
Chapters
4
through
7,
evaluates
total
trihalomethane
(
TTHM)
and
five
haloacetic
acid
(
HAA5)
levels
throughout
the
distribution
system.
An
SSS
uses
historical
data,
distribution
system
models,
or
other
analyses
as
the
basis
to
select
Stage
2B
compliance
monitoring
sites.

To
ensure
an
SSS
evaluates
and
characterizes
TTHM
and
HAA5
formation
throughout
the
distribution
system
to
the
extent
required
for
the
IDSE,
the
study
must
provide
equivalent
or
superior
data
for
the
selection
of
new
Stage
2B
compliance
monitoring
sites
compared
to
an
SMP
(
40
CFR
141.603).
The
SSS
option
allows
systems
with
extensive
historical
disinfection
byproduct
(
DBP)
and
other
water
quality
data,
previous
pertinent
studies,
or
other
detailed
knowledge
of
the
distribution
system
operations
to
use
these
resources
as
the
basis
for
choosing
new
monitoring
sites.
Conducting
an
SSS
can
also
allow
a
system
to
avoid
the
duplication
of
DBP
field
monitoring
efforts
if
significant
TTHM
and
HAA5
monitoring,
in
addition
to
the
Stage
1
DBPR
requirements,
has
been
performed
in
the
past.
The
development
of
new
detailed
and
expensive
studies
is
neither
intended
nor
required.

This
chapter
describes
two
approaches
to
completing
an
SSS:

1)
The
use
of
historical
TTHM
and
HAA5
data
that
are
equivalent
or
superior
to
data
that
would
be
obtained
under
the
IDSE
SMP.

2)
The
use
of
a
calibrated
water
distribution
system
hydraulic
model
and
at
least
one
round
of
new
sampling
conducted
during
the
month
of
peak
historical
TTHM
levels
(
or
the
month
of
peak
distribution
system
water
temperature
if
peak
TTHM
data
are
not
available).

EPA
recognizes
that
there
are
other
combinations
of
data
and
system
analyses
that
may
provide
equivalent
or
superior
selection
of
Stage
2B
compliance
sites
(
a
few
alternative
SSSs
are
discussed
later
in
this
chapter).
Final
approval
of
an
SSS
is
dependent
on
the
State
 
the
approaches
described
here
are
only
guidance.

This
chapter
focuses
on
requirements
and
general
guidelines
for
completing
an
SSS
using
historical
data
or
a
water
distribution
system
model.
It
also
describes
how
systems
can
use
results
of
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
1
EPA
defines
a
combined
distribution
system
as
the
totality
of
the
distribution
systems
of
wholesale
systems
and
of
the
consecutive
systems
that
receive
finished
water
from
those
wholesale
systems
(
40
CFR
141.2).

July
2003
­
Proposal
Draft
All
Systems
3­
2
their
SSSs
to
select
final
Stage
2B
monitoring
sites
and
report
results
and
final
site
selection
to
their
States.

The
remainder
of
this
chapter
is
organized
as
follows:

3.2
Schedule
for
an
SSS
3.3
SSS
Using
Historical
Data
3.4
SSS
Using
a
Water
Distribution
System
Model
3.5
Alternative
SSSs
3.6
Selecting
Stage
2B
Compliance
Monitoring
Sites
Using
SSS
Results
3.7
Reporting
Results
to
the
State
3.2
Schedule
for
an
SSS
The
rule
requires
systems
to
submit
their
IDSE
report
[
2
years
after
rule
promulgation]
if
they
are
on
the
early
schedule,
or
[
4
years
after
rule
promulgation]
if
they
are
on
the
late
schedule
(
40
CFR
141.600(
c)).
The
schedule
is
based
on
the
population
of
the
largest
system
in
the
combined
distribution
system.
1
See
section
1.4
for
guidance
on
determining
whether
a
system
is
on
the
large
or
small
system
schedule.

Systems
on
the
early
schedule
will
have
to
decide
whether
to
conduct
an
SSS
or
SMP
before
States
are
expected
to
receive
primacy
for
the
Stage
2
DBPR.
Therefore,
States
will
generally
not
be
able
to
formally
approve
or
accept
the
use
of
an
SSS
prior
to
the
time
when
SMP
field
sampling
should
begin.
This
guidance
manual
contains
criteria
that
States
may
use
to
evaluate
the
system­
specific
study.
Systems
should
carefully
consider
the
data
and
information
sources
available
for
completing
an
SSS.
If
there
are
doubts
about
the
completeness
of
data
for
an
SSS,
systems
should
consider
completing
an
SMP
instead
of
an
SSS.
Systems
are
encouraged
to
contact
their
State
for
an
opinion
if
there
are
questions
about
the
adequacy
of
an
SSS.
If
a
system
decides
not
to
conduct
the
SMP
and
completes
an
SSS
that,
after
the
State
review
process,
is
ultimately
not
approved
by
the
State,
that
system
would
be
in
violation
of
the
Stage
2
DBPR.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
3
3.3
SSS
Using
Historical
Data
This
section
describes
an
SSS
that
uses
historical
TTHM
and
HAA5
data
to
select
Stage
2B
monitoring
sites.
It
provides
guidelines
for
determining
whether
historical
data
are
appropriate
for
use
in
an
SSS
(
e.
g.,
DBP
sampling
location
and
frequency,
sampling
periods,
analytical
quality,
and
correlation
with
existing
system
conditions).
Sections
3.6
and
3.7
build
on
this
section
by
showing
how
final
Stage
2B
compliance
monitoring
sites
are
selected
based
on
SSS
results
and
by
listing
minimum
IDSE
SSS
reporting
requirements.

3.3.1
Sample
Site
and
Frequency
Historical
data
should
be
representative
of
your
entire
distribution
system.
At
a
minimum
these
data
should
meet
the
overall
SMP
requirements
with
respect
to:

°
Number
of
sites
°
Location
of
sites
°
Number
of
dual
sample
sets
per
site
Tables
1.4
and
1.5
summarize
the
SMP
sample
site
requirements
for
various
system
sizes,
source
waters,
and
residual
disinfectant
types
(
Chapters
4
through
7
provide
additional
details).
Historical
sites
that
are
generally
equivalent
to
each
of
the
required
SMP
sites
should
be
specifically
identified
(
e.
g.,
near
entry
point,
average
residence
time,
representative
high
TTHM
concentration).
Using
historical
data
from
more
sites
than
required
for
the
SMP
is
acceptable
and
encouraged.

Consistent
with
SMP
requirements,
TTHM
and
HAA5
data
should
have
been
collected
at
each
site.
The
interval
for
historical
data
collection
(
e.
g.,
quarterly,
biannually)
should
generally
reflect
SMP
requirements
for
monitoring
frequency.
At
a
minimum,
at
least
one
set
of
historical
TTHM
and
HAA5
samples
should
represent
the
month
of
peak
distribution
system
temperature
or
peak
historical
TTHM
levels.
The
collection
period
for
historical
data
should
be
at
least
one
full
year,
and
sampling
should
have
been
conducted
at
evenly
spaced
intervals
throughout
the
collection
period.

Specific
sampling
requirements
of
the
SMP
do
not
have
to
be
mirrored
precisely
in
a
historical
data
set,
but
the
overall
intent
of
the
SMP
should
be
satisfied.
For
example:

°
If
more
sites
per
plant
were
sampled
than
are
required
by
the
SMP,
fewer
sample
sets
(
e.
g.,
quarterly
instead
of
bimonthly)
may
be
acceptable
for
the
SSS,
as
long
as
the
sample
sets
were
collected
at
evenly
spaced
time
intervals.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
4
ALL
Historical
Data
>
50%
of
Historical
Data
IDSE
Report
Due
Stage
2
DBPR
Promulgation
[
Year
1]
[
Year
10]
[
Year
9]
[
Year
8]
[
Year
7]
[
Year
6]
[
Year
5]
[
Year
4]
[
Year
3]
[
Year
2]
°
If
samples
were
collected
quarterly
(
rather
than
bimonthly)
for
multiple
years
(
rather
than
1
year)
at
an
appropriate
number
of
sites,
the
data
may
be
acceptable
for
an
SSS,
as
long
as
the
sample
sets
were
collected
at
evenly
spaced
time
intervals.

If
historical
data
equivalent
to
the
requirements
of
an
SMP
are
not
available,
the
completion
of
an
alternative
SSS
using
a
combination
of
historical
and
newly
collected
TTHM
and
HAA5
data
may
be
appropriate
(
see
section
3.5).

3.3.2
Analytical
Data
Quality
Historical
TTHM
and
HAA5
samples
should
have
been
analyzed
using
approved
methods
by
a
laboratory
certified
to
perform
these
measurements
under
the
Drinking
Water
Certification
Program.
Systems
should
contact
their
laboratory
or
State
to
confirm
certification
status.
Appendix
C
describes
the
approved
analytical
methods
for
TTHM
and
HAA5.
Note,
HAA5
data
collected
before
2002
were
likely
not
to
have
been
analyzed
by
certified
laboratories.

3.3.3
Historical
Sampling
Period
To
ensure
historical
data
represents
current
water
treatment
and
distribution
conditions,
only
data
collected
within
the
10
years
preceding
the
due
date
of
the
IDSE
report
should
be
used
for
an
SSS.
Also,
at
least
50
percent
of
the
historical
samples
should
have
been
collected
within
5
years
prior
to
your
system's
IDSE
report
due
date.
Figures
3.1
and
3.2
depict
recommended
limits
on
historical
sampling
periods
according
the
early
and
late
schedules.

Figure
3.1
Recommended
Limits
of
Historical
Sampling
Period
for
Systems
on
the
Early
Schedule
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
5
ALL
Historical
Data
>
50%
of
Historical
Data
IDSE
Report
Due
Stage
2
DBPR
Promulgation
[
Year
1]
[
Year
10]
[
Year
9]
[
Year
8]
[
Year
7]
[
Year
6]
[
Year
5]
[
Year
4]
[
Year
3]
[
Year
2]
Figure
3.2
Recommended
Limits
of
Historical
Sampling
Period
for
Systems
on
the
Late
Schedule
3.3.4
Treatment
and
Source
Conditions
Historical
data
should
reflect
the
source
water(
s)
and
treatment
configuration
in
place
at
the
time
that
your
IDSE
report
is
due
(
see
Figures
3.1
and
3.2
for
IDSE
report
schedules).
Within
the
historical
period,
temporary
changes,
such
as
regular
maintenance,
rehabilitation,
and
upgrades
of
plant
processes
are
generally
acceptable.
Temporary
changes
to
disinfection
practices
(
e.
g.,
short
duration
switches
to
free
chlorine
for
secondary
disinfection
to
control
nitrification
in
a
chloraminated
system
and
short
duration
emergency
and
special
disinfection
operations)
are
also
generally
acceptable
within
the
historical
sampling
period.
Data
from
short
duration
periods
of
unusual
(
not
routine
seasonal)
system
conditions
could
be
excluded
from
the
analysis
of
the
historical
data
set,
with
appropriate
justification
to
the
State.
Routine,
repeating,
and
seasonal
changes
in
supply
or
treatment
should
be
allowable
during
the
historical
data
period.

If
a
system
made
permanent
changes
that
significantly
affected
DBP
formation,
plant
production
rates,
and/
or
distribution
systems,
only
historical
data
representing
conditions
after
the
change
should
be
used
for
an
SSS.
Significant
permanent
treatment
process
or
source
changes
that
should
be
considered
"
cutoff
points"
for
use
of
historical
data
include:

°
Permanent
changes
in
primary
or
secondary
disinfection
type
or
practice,
such
as:

 
Using
a
different
disinfectant
for
primary
disinfection
 
Switching
to
chloramines
for
secondary
disinfection
 
Adding
booster
chlorination
in
the
distribution
system
°
Major,
permanent
changes
in
raw
water
sources
that
significantly
affected
DBP
concentrations
in
water
produced
by
the
plant
(
e.
g.,
addition
of
a
new
water
source)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
6
°
Major,
permanent
changes
to
plant
configuration
that
affect
disinfectant
contact
time
(
e.
g.,
increasing
clearwell
volume
with
same
flow
rate
of
water
through
the
clearwell)

°
Major,
permanent
changes
in
treatment
that
affected
DBP
concentration
in
water
produced
by
the
plant
(
e.
g.,
addition
of
granular
activated
carbon
(
GAC)
or
membranes)

Minor
treatment
changes
that
affected
the
magnitude
of
TTHM
and
HAA5
levels
in
the
distribution
system,
but
that
are
unlikely
to
have
changed
the
DBP
formation
kinetics
and
relative
levels
of
TTHMs
and
HAA5s
in
different
parts
of
the
system,
are
acceptable.
For
example,
improved
control
of
an
existing
coagulation
process
or
minor
changes
in
coagulation
pH
that
reduce
average
levels
of
DBP
precursors
is
acceptable,
but
switching
from
chlorine
to
ozone
for
primary
disinfection
is
not.
If
treatment
process
or
source
changes
have
occurred
and
data
collected
prior
to
the
change
are
utilized
in
an
SSS,
then
the
use
of
the
data
should
be
justified
with
an
explanation
of
the
change
and
a
demonstration
that
it
is
unlikely
to
have
significantly
affected
the
relative
TTHM
and
HAA5
levels
in
the
distribution
system.

3.3.5
Distribution
System
Conditions
The
historical
data
set
should
also
reflect
the
overall
distribution
system
hydraulic
operation
and
large
scale
movement
of
water
through
the
system
at
the
time
an
IDSE
report
is
due
(
see
Figures
3.1
and
3.2
for
IDSE
report
schedules).
Normal
daily
and
seasonal
changes
in
system
operation
during
your
historical
sampling
period
should
be
acceptable.
Supply
points,
pressure
zones,
large
transmission
mains,
pump
stations,
storage
tanks,
and
large
wholesale
and
retail
customers
should
generally
be
consistent
throughout
the
historical
sampling
period,
but
do
not
have
to
remain
exactly
the
same.
A
steady
increase
in
water
demand
during
the
historical
sampling
period
due
to
population
growth
should
be
acceptable
if
it
did
not
result
in
major
changes
in
water
flow
pattern
and
age
within
the
distribution
system.

Significant
distribution
system
changes
that
should
be
considered
as
"
cutoff
points"
for
use
of
historical
data
include:

°
Major,
permanent
changes
in
plant
production
rates,
high
service
or
booster
pump
station
pumping
rates,
or
pump
operation
schemes
that
significantly
change
the
influence
zones
of
treatment
plants
°
Major,
permanent
changes
in
water
use
patterns
or
system
hydraulics,
such
as:

 
addition
or
removal
of
a
very
high
water
use
industrial,
institutional,
or
wholesale
customer
 
addition,
deletion,
or
replacement
of
mains,
pump
stations,
or
storage
tanks
that
significantly
change
water
flow
patterns
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
7
Usable
Historical
Data
>
50%
of
Historical
Data
IDSE
Report
Due
Stage
2
DBPR
Promulgation
[
Year
1]
[
Year
10]
[
Year
9]
[
Year
8]
[
Year
7]
[
Year
6]
[
Year
5]
[
Year
4]
[
Year
3]
[
Year
2]

Installed
New
Transmission
Line
from
the
Treatment
Plant
to
an
Area
to
Improve
Fire
Flow
Data
prior
to
change
is
not
useful
 
looping
of
mains
This
list
is
not
inclusive
 
systems
should
always
use
best
professional
judgement
to
determine
if
a
distribution
system
modification
affected
the
location
of
TTHM
and
HAA5
peaks.

Figure
3.3
provides
an
example
of
the
acceptable
historical
sampling
period
for
a
surface
water
plant
serving
at
least
10,000
people
that
placed
a
new
large
finished
water
transmission
main
into
service
within
the
last
10
years,
changing
distribution
system
hydraulics
(
e.
g.,
flow
rates,
directions,
and
patterns).

Figure
3.3
Example
of
Historical
Data
Limitations
for
a
System
on
the
Early
Schedule
With
a
Significant
Change
in
Distribution
System
Hydraulics
3.4
SSS
Using
a
Water
Distribution
System
Model
This
section
describes
an
SSS
that
uses
a
detailed,
comprehensive,
and
well­
calibrated
water
distribution
system
model
to
help
select
Stage
2B
monitoring
sites.
There
are
two
types
of
water
distribution
system
models
that
can
be
used
for
the
SSS
 
hydraulic
models
and
water
quality
models.
Because
the
complexity
and
accuracy
of
the
models
differ,
section
3.4.1
recommends
minimum
requirements
that
should
be
met
by
the
model.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
8
Hydraulic
models
can
predict
water
age,
but
they
do
not
predict
changes
in
water
quality
parameters,
such
as
chlorine
or
TTHM
concentrations.
Water
quality
models
can
reasonably
predict
disinfectant
residuals
and,
in
some
cases
TTHM
concentrations,
in
addition
to
hydraulic
patterns
in
distribution
systems.
A
well­
calibrated
water
quality
model
may
provide
more
data
that
could
lead
to
superior
selections
of
Stage
2B
compliance
sites
compared
to
hydraulic
models.
However,
proper
calibration
of
the
water
quality
component
can
be
a
difficult
task
and
is
typically
done
with
much
less
accuracy
than
calibration
of
the
hydraulic
component.
Thus,
the
minimum
requirements
for
the
predefined
SSS
are
focused
only
on
the
hydraulic
component
of
water
distribution
system
models.
If
a
system
decides
to
use
a
water
quality
model,
they
are
encouraged
to
provide
information
on
the
water
quality
calibration
to
the
State.

Operation
of
a
water
distribution
system
should
be
simulated
over
extended
periods
to
reflect
maximum
residence
time
in
the
system
under
conditions
of
high
TTHM
and
HAA5
formation
potential.
The
period
of
high
TTHM
and
HAA5
formation
potential
for
many
systems
will
occur
during
the
summer
months
(
although
this
is
not
the
case
for
all
systems).
The
operation
and
behavior
of
treated
water
storage
facilities
must
also
be
well­
characterized
in
the
model.
The
results
should
then
be
used
to
determine:

°
The
spatial
and
temporal
patterns
of
water
movement
from
all
plants
(
if
there
are
multiple
sources
of
supply)

°
The
typical
pattern
of
residence
time
in
the
system
during
the
period
of
high
TTHM
and
HAA5
formation
potential
Model
results
should
be
combined
with
at
least
one
round
of
TTHM
and
HAA5
sampling
at
sites
that,
at
a
minimum,
meet
SMP
requirements
for
number
and
type
of
site.
These
results
will
be
used
in
selecting
final
Stage
2B
compliance
monitoring
sites.

This
section
provides
detailed
guidance
for
the
following
topics:

°
Minimum
model
requirements
(
including
modeled
components,
simulation
of
water
consumption,
and
model
calibration)

°
Selecting
preliminary
sites
that
meet
SMP
requirements
based
on
model
outputs
°
Performing
at
least
one
round
of
TTHM
and
HAA5
monitoring
during
the
month
of
peak
TTHM
concentrations
or
peak
temperature
(
additional
sampling
beyond
one
round
or
at
additional
sites
is
allowed
and
encouraged)

Section
3.7
shows
how
modeled
results,
one
round
of
monitoring
data,
and
TTHM
and
HAA5
compliance
monitoring
results
are
used
to
select
final
Stage
2B
compliance
monitoring
sites.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
9
The
option
of
using
a
water
distribution
system
model
is
intended
to
allow
systems
that
have
models
to
use
their
existing
technical
resources
to
perform
the
IDSE.
For
many
systems,
developing
a
detailed
and
well­
calibrated
water
distribution
system
model
from
scratch
and
training
staff
to
use
it
will
cost
more
than
conducting
an
SMP.
If
the
model
will
be
used
for
other
purposes
after
the
completion
of
the
SSS,
such
as
optimizing
system
operations
and
prioritizing
capital
improvements,
then
the
cost
of
the
model
development
may
be
justified.

If
your
model
does
not
meet
the
criteria
described
in
this
section,
you
may
be
able
to
upgrade
the
model
or
use
it
in
combination
with
other
data
and/
or
analyses
for
your
SSS.
These
alternative
SSSs
might
involve
the
use
of
less
robust
models,
supplemented
with
data
from
tracer
studies
or
more
extensive
historical
or
new
TTHM
and
HAA5
monitoring
data
(
see
Section
3.5
for
alternative
SSSs).

3.4.1
Minimum
Model
Requirements
In
general,
your
water
distribution
system
model
should
be
more
comprehensive
for
the
purpose
of
an
SSS
than
models
typically
used
for
long­
range
capital
improvement
program
analysis
(
e.
g.,
master
planning).
A
calibrated
hydraulic
model
intended
for
detailed
distribution
system
design
(
e.
g.,
for
system
improvements)
or
operational
studies
is
likely
to
be
adequate.
A
well­
calibrated
water
quality
model
is
likely
to
be
acceptable.

Because
systems
are
always
changing
(
e.
g.,
population
growth,
new
industries,
aging
of
mains),
it
is
important
that
your
model
generally
reflect
system
conditions
and
demand
at
the
time
of
the
IDSE
SSS.
A
model
that
has
not
been
updated
or
calibrated
in
the
last
10
years
is
unlikely
to
be
adequate
for
the
SSS.

Note
that
the
guidelines
in
this
section
are
not
comprehensive
 
every
distribution
system
is
unique.
Systems
and
States
should
always
use
their
best
professional
judgement
when
determining
model
adequacy
for
the
SSS.

3.4.1.1
Model
Details
Most
water
distribution
system
models
do
not
include
every
pipe
in
a
distribution
system.
Typically,
small
pipes
near
the
periphery
of
the
system
and
other
pipes
that
affect
relatively
few
customers
are
excluded
to
a
greater
or
lesser
extent
depending
on
the
intended
use
of
the
model.
This
process
is
called
skeletonization.

It
is
a
generally
accepted
practice
to
skeletonize
models
to
a
certain
extent
depending
on
the
model's
intended
use.
To
be
used
for
the
purposes
of
this
predefined
SSS,
the
model
should
be
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
10
relatively
detailed
and
include
the
majority
of
pipes
in
the
distribution
system.
EPA
recommends
that
a
model
used
for
an
SSS
generally
include
the
following:

°
At
least
50
percent
of
total
pipe
length
in
the
distribution
system
°
At
least
75
percent
of
the
pipe
volume
in
the
distribution
system
°
All
12­
inch
diameter
and
larger
pipes
°
All
8­
inch
and
larger
pipes
that
connect
pressure
zones,
influence
zones
from
different
sources,
storage
facilities,
major
demand
areas,
pumps,
and
control
valves,
or
are
known
or
expected
to
be
significant
conveyors
of
water
°
All
6­
inch
and
larger
pipes
that
connect
remote
areas
of
a
distribution
system
to
the
main
portion
of
the
system
°
All
storage
facilities,
with
controls
or
settings
applied
to
govern
the
open/
closed
status
of
the
facility
that
reflect
standard
operations
°
All
active
pump
stations,
with
realistic
controls
or
settings
applied
to
govern
their
on/
off
status
that
reflect
standard
operations
°
All
active
control
valves
or
other
system
features
that
could
significantly
affect
the
flow
of
water
through
the
distribution
system
(
e.
g.,
interconnections
with
other
systems,
valving
between
pressure
zones)

If
a
model
used
to
conduct
an
SSS
does
not
generally
meet
these
criteria,
additional
justification
of
the
suitability
of
the
model
for
use
in
an
SSS
should
be
provided
to
the
State
in
the
IDSE
report.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
11
3.4.1.2
Accurate
Simulation
of
Water
Consumption
Water
consumption
(
demand)
should
be
accurately
simulated
in
the
model:

°
Water
demand
should
be
allocated
among
the
nodes
of
the
model
in
a
manner
that
reflects
the
actual
spatial
distribution
of
such
demand
throughout
the
system
and
with
fineness
of
detail
appropriate
for
the
system
size,
in
order
to
assure
the
model
will
provide
a
realistic
simulation
of
water
flow
throughout
the
system.

°
As
the
level
of
detail
(
percentage
of
pipe
modeled
compared
to
actual
total
length
of
pipe
in
the
system)
of
a
model
increases,
the
percentage
of
nodes
with
demand
assignments
can
sometimes
be
less
than
that
would
be
needed
in
a
less
detailed
model,
without
significantly
impacting
the
overall
accuracy
of
the
model.

°
Water
demand
should
generally
be
assigned
to
all
end
nodes
so
that
the
flow
of
water
is
simulated
in
dead­
end
pipes
and
remote
areas
of
a
system.

°
Demand
data
should
reflect,
at
a
minimum,

S
domestic
water
use
S
large
commercial
and
industrial
users
S
unaccounted
for
system
water
losses
S
seasonal
trends
°
A
system­
specific,
diurnal
(
24­
hour)
demand
pattern
should
be
applied
to
the
overall
system
demand.
Demand
patterns
can
be
derived
from
a
review
of
master
meter
flows,
tank
levels,
pumping
rates,
or
other
similar
operational
data.

°
The
model
should
accurately
simulate
seasonal
system
configuration
and
operational
changes
to
meet
changes
in
demand,
such
as
a
reservoir
that
is
taken
out
of
service
during
winter
months,
or
a
large
seasonal
user
(
e.
g.,
a
campground).

3.4.1.3
Model
Calibration
Generally,
calibration
is
the
process
of:

°
Compiling
field
data
on
pressures,
flows,
and
tank
water
levels
in
the
system
under
known
conditions
°
Comparing
model
results
with
field
data
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
12
°
Adjusting
the
model
(
e.
g.,
pipe
roughness
factors,
tank/
pump
operational
settings,
etc.)
to
agree
with
field
data
Calibration
is
never
exact,
and
there
are
no
official
calibration
standards
or
guidelines
in
the
United
States.
There
is
general
agreement
in
the
modeling
profession
that
the
extent
of
calibration
should
reflect
the
intended
uses
of
the
model.
For
example,
a
more
rigorous
model
calibration
is
expected
when
the
model
is
used
for
design
work
compared
to
master
planning.
For
the
purposes
of
the
SSS,
a
slightly
less
rigorous
calibration
compared
to
design
work
is
most
likely
to
be
adequate.
Calibration
performed
several
years
ago
for
the
purposes
of
general
master
planning
may
not
be
acceptable.
For
more
information
regarding
the
calibration
of
distribution
system
hydraulic
models,
refer
to
Modeling
Water
Quality
in
Drinking
Water
Distribution
Systems
(
Clark
and
Grayman
1998,
AWWA)
or
Advanced
Water
Distribution
Modeling
and
Management
(
Beckwith
et
al.
2002,
Haested
Methods),
or
other
reference
books.

It
is
recommended
that
systems
verify
the
reasonableness
of
their
model
calibration
by
comparing
residence
time
estimates
with
disinfectant
residual
data.
To
do
this,
plot
(
electronically
or
by
hand)
the
residence
time
estimates
obtained
from
your
model
and
disinfectant
residual
monitoring
results
on
a
map
of
the
distribution
system.
A
system
should
generally
find
that
average
disinfectant
residuals
are
similar
for
locations
with
equivalent
residence
times
(
disregarding
pipe
tuberculation,
biofilm,
etc.).
If
actual
disinfectant
residuals
are
not
similar
in
areas
with
similar
modeled
residence
times,
it
is
possible
your
calibration
is
insufficient
or
differences
in
tuberculation
and
biofilm
between
the
areas
being
compared
have
affected
the
disinfectant
residuals.
If
systems
encounter
this
situation,
but
believe
their
model
calibration
is
accurate,
they
should
provide
a
justification
for
the
data
inconsistency
in
the
IDSE
report.

3.4.2
Identifying
Preliminary
Sites
Using
Model
Results
To
select
preliminary
monitoring
sites
using
a
water
distribution
system
model,
systems
should:

°
Run
the
model
in
extended
period
simulation
(
EPS)
mode
until
a
consistent,
repeating
temporal
pattern
of
water
age
is
established
at
all
nodes
of
the
model.
Generally,
the
model
should
be
run
under
high
DBP
formation
conditions
(
typically
summer
months).

°
Choose
preliminary
sites
satisfying
the
SMP
sample
site
requirements
based
on
water
age
results.
(
See
section
1.3.5
for
a
summary
of
SMP
requirements.)

The
rule
requires
an
SSS
include
an
analysis
demonstrating
that
the
SSS
characterized
expected
TTHM
and
HAA5
levels
throughout
the
distribution
system
(
40
CFR
141.604(
a)).
This
approach
recommends
systems,
at
a
minimum,
conduct
one
round
of
sampling
(
collecting
dual
sample
sets)
at
the
preliminary
sites
during
the
month
of
peak
TTHM
levels
or
water
temperature
in
the
distribution
system
(
one
round
of
monitoring
is
addressed
in
section
3.4.3).
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
13
Model
results
and
all
available
TTHM
and
HAA5
data
monitoring
results
are
combined
to
select
Stage
2B
compliance
monitoring
sites
(
see
section
3.6).
The
use
of
a
water
quality
model
would
be
similar,
but
instead
of
choosing
preliminary
sites
based
on
water
age
results,
chlorine
residual
or
TTHM
results
would
be
used.
The
following
sections
describe
a
pre­
defined
SSS
option
that
involves
the
use
of
a
water
distribution
system
model
for
identifying
preliminary
monitoring
sites.

3.4.2.1
EPS
Modeling
to
Estimate
Residence
Time,
Influence
Zones,
and
Mixing
Zones
When
a
water
distribution
system
model
is
used
to
estimate
residence
times,
influence
zones,
and
mixing
zones,
the
modeling
must
be
performed
in
EPS
mode
instead
of
the
steady­
State
simulation
mode.
In
EPS
modeling,
variables
such
as
water
demands
and
tank
water
levels
are
allowed
to
change
over
time
(
in
steady­
State
modeling,
all
variables
remain
constant
over
time).
EPS
models
should
be
run
until
a
consistent
or
consistently
repeating
pattern
of
residence
time
is
established
at
all
nodes
of
the
model.
Typically,
a
repeating
24­
hour
pattern
of
water
use
(
demand)
and
system
operations
are
assumed
in
EPS
modeling.
Depending
on
particular
system
characteristics
and
the
specific
starting
conditions
imposed
on
the
model,
an
EPS
model
may
require
a
simulation
time
of
7
to
21
days
or
more
for
a
consistent
pattern
of
residence
time
to
develop.
An
EPS
model
usually
needs
to
be
run
much
longer
than
the
actual
maximum
residence
time
of
water
in
a
particular
distribution
system
before
a
consistent
pattern
of
residence
time
is
attained
at
the
system
extremities.

The
model
should
be
run
under
conditions
of
high
DBP
formation
potential.
In
most
areas
of
the
United
States,
water
demand
and
system
operation
vary
seasonally.
Seasonal
variations
can
generally
be
classified
into
summer
conditions
(
high
usage),
winter
conditions
(
low
usage),
springautumn
conditions
(
medium
usage),
or
wet
and
dry
period
conditions.
In
applying
a
model
to
select
preliminary
Stage
2B
monitoring
sites,
the
examination
of
summer
usage
will
generally
suffice
if
summer
conditions
represent
the
period
of
peak
TTHM
formation
potential.
The
consideration
of
additional
usage
conditions
is
acceptable.

In
systems
with
multiple
plants,
source
tracing
should
be
used
to
determine
zones
of
influence
and
mixing
zones.
Most
models
have
a
"
source
tracing"
option
in
which
the
percentage
of
water
coming
from
a
single
source
can
be
traced
over
the
course
of
several
days.
By
tracing
each
source
separately,
a
map
can
be
generated
showing
areas
that
predominantly
receive
water
from
a
single
source
and
areas
with
mixing
zones
where,
either
on
a
diurnal
or
a
seasonal
basis,
water
is
received
from
multiple
sources.
This
information
is
used
to
make
informed
selections
of
sampling
sites
that
are
representative
of
a
single
source
or
a
mixing
zone.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
14
3.4.2.2
Preliminary
Sample
Site
Selection
to
Meet
SMP
Criteria
The
residence
time,
influence
zone,
and
mixing
zone
information
developed
through
modeling
should
be
used
to
select
preliminary
sites.
The
number
of
preliminary
sites
should
equal
or
exceed
the
required
number
of
SMP
sites.
Stage
1
monitoring
sites
should
not
be
selected
as
preliminary
sites
for
one
round
of
monitoring.
The
type
of
preliminary
sites
(
near
entry
point,
high
TTHM,
high
HAA5,
and
average
residence
time)
should
also
generally
mirror
SMP
sites
for
your
system
size
and
source
water
type.
See
section
1.3.5
for
a
summary
of
SMP
site
criteria
according
to
system
size
and
source
water
type;
see
Chapters
4
through
7
for
more
details.

The
next
three
sections
provide
detailed
guidance
on
selecting
high
TTHM,
high
HAA5,
and
average
residence
time
sites.
Appendix
B
provides
additional
information
regarding
TTHM
and
HAA5
formation
that
could
be
useful
in
selecting
these
sets.
Because
hydraulic
models
usually
are
somewhat
skeletonized
and
have
varying
degrees
of
calibration
and
accuracy
of
demand
allocation,
best
professional
judgement
should
always
be
used
when
analyzing
the
results
and
using
model
outputs
to
assist
in
the
selection
of
preliminary
sites.

High
TTHM
Sites
High
residence
time
locations
(
most
often
high
TTHM
sites)
can
be
identified
by
reviewing
the
modeled
water
age
at
each
node
in
the
model.
When
the
run
time
of
an
EPS
model
is
long
enough
to
produce
a
consistent
pattern
of
water
age
values
at
all
nodes,
sometimes
with
repeating
fluctuations
due
to
diurnal
variations
in
water
demands,
then
the
water
age
values
at
the
model
nodes
can
be
used
for
the
purposes
of
identifying
high
residence
time
locations.

One
way
to
show
high
residence
time
sites
is
by
color
coding
each
model
node
according
to
its
residence
time.
High
TTHM
sites
should
be
chosen
from
the
area
or
areas
of
the
distribution
system
where
the
high
residence
time
model
nodes
are
located.
The
sites
do
not
have
to
be
chosen
at
the
exact
location
of
a
model
node,
just
in
the
general
area
identified
by
the
model
results.

Precautions
in
using
model
data
to
select
high
TTHM
sites
include:

°
If
no
water
demand
is
applied
to
dead­
end
nodes
in
a
model
or
if
the
water
demand
in
a
dead­
end
is
highly
uncertain,
the
water
age
results
for
those
nodes
can
be
unrealistic
and
meaningless.

°
The
accuracy
of
water
age
estimates
from
a
model
generally
decreases
as
the
model
moves
from
large
diameter
mains
to
small
diameter
mains
to
subdivision
piping
and
dead­
ends.
This
is
due
to
the
increasing
uncertainty
in
water
usage
rates
as
the
system
moves
away
from
large,
aggregate
demands
to
smaller
demands
exerted
by
a
few
customers
or
a
single
customer.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
15
°
If
the
model
is
skeletonized,
the
model
results
for
high
residence
time
areas
should
be
compared
to
maps
of
the
actual
distribution
system
piping
and
to
actual
customer
locations
in
those
areas
before
sample
sites
are
finalized
in
order
to
assure
that
the
sample
site
is
representative
of
the
actual
distribution
system
and
not
just
the
skeletonized
model
in
the
high
residence
time
areas.

°
Residence
time
is
just
one
factor
for
identifying
high
TTHM
sites
and
should
be
compared
with
other
distribution
system
data
(
e.
g.,
disinfectant
residual
data)
before
making
preliminary
site
selections.

In
some
cases,
there
can
be
zones
in
the
distribution
system
where
water
flowing
from
opposite
directions
meet.
This
can
occur
in:

°
Long,
looping
mains
°
The
interface
of
the
influence
zones
of
two
or
more
different
supply
points
°
Areas
where
different
pressure
zones
meet
within
one
system
This
type
of
area
is
sometimes
called
a
"
mixing
zone"
and
may
act
as
a
hydraulic
dead­
end.
Mixing
zones
can
occur
anywhere
in
the
distribution
system,
but
occur
more
often
in
the
central
portion
of
a
distribution
system.
If
the
water
demand
in
the
mixing
zone
is
low,
then
the
water
age
and
TTHM
concentrations
could
be
high.
Water
distribution
system
models
can
be
useful
in
locating
mixing
zones
and
identifying
high
TTHM
sites
within
the
mixing
zone.

High
HAA5
Sites
The
criteria
and
procedure
for
selecting
high
HAA5
sites
using
a
hydraulic
model
is
generally
the
same
as
that
described
above
for
selecting
high
TTHM
sites
with
one
important
difference:
the
sites
chosen
to
represent
high
HAA5
should
have
a
detectable
disinfectant
residual.
HAA5
concentrations
typically
increase
in
distribution
systems
as
water
age
increases
but
can
also
decrease
if
disinfectant
residuals
are
not
present
and
biological
activity
is
high.
It
is
generally
recommended
that
high
HAA5
sites
be
selected
in
areas
with
a
minimum
chlorine
residual
of
0.2
mg/
L
or
a
minimum
chlorine
residual
or
0.5
mg/
L.

Average
Residence
Time
Sites
Average
residence
time
sites
can
be
selected
from
sites
with
residence
times
close
to
the
flowweighted
mean
of
all
nodal
residence
times
(
or
system
average).
As
with
selecting
high
TTHM/
HAA5
sites,
color
coding
nodes
by
nodal
residence
time
can
be
helpful.
Preliminary
sample
sites
should
be
chosen
from
the
area
or
areas
of
the
distribution
system
where
the
nodal
residence
time
is
close
to
the
system
average.
The
preliminary
sites
do
not
have
to
be
chosen
at
the
exact
location
of
a
model
node,
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
16
just
in
the
general
area
identified
by
the
model
results.
Selected
sites
should
represent
the
entire
distribution
system
and
should
not
be
clustered.

3.4.3
Performing
At
Least
One
Round
of
Sampling
Although
hydraulic
models
can
be
used
to
reasonably
predict
residence
times,
the
behavior
of
HAA5
cannot
be
directly
predicted
based
on
residence
time
in
a
distribution
system.
Therefore,
to
meet
the
rule
requirement
of
demonstrating
model
accurately
characterized
expected
TTHM
and
HAA5
levels
(
40
CFR
141.604(
a)),
this
approach
recommends
systems
perform
at
least
one
round
of
sampling
at
preliminary
sites
(
i.
e.,
collecting
dual
sample
sets
at
each
site).
Generally,
the
TTHM
concentrations
from
this
sampling
should
confirm
the
model
predictions
of
residence
time
and
verify
the
selection
of
preliminary
sites.

If
only
one
round
of
sampling
is
performed,
it
should
occur
in
the
month
of
peak
TTHM
levels
or
water
temperature
in
the
distribution
system.
Additional
rounds
of
sampling
are
allowed
and
encouraged.
All
results
should
be
considered
in
the
selection
of
Stage
2B
compliance
monitoring
sites
and
included
in
the
IDSE
report.
Stage
1
DBPR
compliance
monitoring
and
other
historical
TTHM
and
HAA5
data
should
be
considered,
if
available,
and
included
in
the
IDSE
report.

If
the
results
from
Stage
1
DBPR
compliance
monitoring
and
the
single
round
of
sampling
are
not
reasonably
consistent
with
modeled
residence
times,
the
potential
reason
for
the
discrepancy
should
be
explained
in
the
IDSE
report.
If
factors
such
as
demand
variations,
distribution
system
operations,
tank
operations,
tank
cleaning,
or
new
construction
are
thought
to
have
impacted
the
sampling
results,
then
the
specifics
of
these
factors
should
be
included
in
the
IDSE
report.
One
or
more
additional
rounds
of
sampling
may
also
be
performed
and
are
encouraged.
Modeling
revisions
might
be
needed
if
actual
conditions
during
the
sampling
were
found
to
be
different
than
modeled
conditions.
In
this
case,
select
new
preliminary
sites
and
repeat
the
monitoring.

It
is
recognized
that
distribution
system
modeling
results
usually
do
not
completely
reflect
the
true
range
and
variability
of
hydraulic
and
water
quality
conditions
that
exist
in
distribution
systems.
This
limitation
of
modeling
allows
for
some
amount
of
variability
between
sampling
and
modeling
results.
However,
if
significant
inconsistencies
exist
between
modeling
results
and
the
required
one
round
of
sampling,
then
additional
explanation
would
need
to
be
provided
in
the
IDSE
report.

3.5
Alternative
SSSs
EPA
recognizes
that
there
are
many
combinations
of
data
and
analyses
that
can
be
used
for
an
SSS.
Potential
combinations
include,
but
are
not
limited
to:

°
Historical
data
supplemented
with
new
data
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
17
°
Historical
data
and
tracer
study
results
°
New
TTHM
and
HAA5
data,
distribution
system
modeling,
and
tracer
study
results
In
general,
any
alternative
SSS
should
be
representative
of
the
majority
of
the
distribution
system,
including
the
extremities,
and
provide
equivalent
or
superior
data
for
the
selection
of
Stage
2B
monitoring
sites
compared
to
an
IDSE
SMP.

Section
3.5.1
lists
questions
that
States
should
consider
when
evaluating
an
alternative
SSS.
Sections
3.5.2
and
3.5.3
provide
guidelines
for
two
alternative
SSSs:
historical
DBP
data
supplemented
with
new
DBP
data,
and
historical
or
new
DBP
data
combined
with
a
tracer
study.
The
guidelines
listed
in
this
section
are
NOT
definitive
 
SSSs
will
always
be
evaluated
on
a
case­
by­
case
basis
by
the
State.

3.5.1
Evaluation
of
Alternative
SSSs
The
following
is
a
list
of
questions
that
States
should
consider
when
evaluating
an
SSS:

1)
Does
the
study
adequately
evaluate
the
extremities?
Does
the
study
target
other
potential
areas
with
long
water
residence
times?

2)
Do
the
historical
data
meet
the
specified
criteria
for
analytical
quality
and
represent
existing
distribution
system
conditions
(
see
section
3.3)?

3)
Does
the
study
cover
at
least
1
continuous
year?

4)
Are
there
data
representing
the
month
of
peak
TTHM
or
highest
temperature?

3.5.2
Historical
Data
Combined
with
New
Data
The
total
number
of
samples
analyzed
should
be
equal
to
or
greater
than
the
total
number
of
samples
required
for
the
IDSE
SMP
(
see
Tables
1.4
and
1.5).
The
type
of
monitoring
site
should
also
satisfy
the
SMP
requirements.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
18
Historical
data
should
meet
the
requirements
and
general
guidelines
in
section
3.3.
New
sampling
should
be
performed
to
fill
in
"
gaps"
in
historical
data
as
needed
to
meet
the
minimum
number
of
samples
and
coverage
of
the
distribution
system.
Treatment,
source
water,
and
distribution
system
conditions
should
be
similar
during
the
historical
and
new
sampling
periods,
in
accordance
with
the
requirements
and
guidelines
in
sections
3.3.4
and
3.3.5.
In
cases
where
all
historical
data
are
used
for
some
locations
and
all
new
data
for
other
locations,
there
should
be
no
permanent
changes
to
treatment,
source
water,
and
distribution
system
conditions
that
affect
the
overall
magnitude
of
TTHM
and
HAA5
concentrations
between
the
historical
and
new
data
sampling
periods.
The
selected
sites
should
adequately
represent
the
entire
distribution
system.

3.5.3
Historical
or
New
DBP
Data
Combined
with
a
Distribution
System
Tracer
Study
Time­
of­
travel
tracer
studies
can
be
used
to
determine
actual
water
residence
times
in
a
distribution
system
under
specific
conditions,
and
are
sometimes
used
to
calibrate
water
distribution
system
models.
They
are
particularly
useful
for
predicting
water
residence
time
in
areas
of
a
system
where
there
is
uncertainty
about
true
pipe
diameters
due
to
poor
records
or
the
buildup
of
corrosion
deposits.
When
pipe
diameters
in
a
model
are
inaccurate,
model
predictions
can
be
very
different
than
the
actual
hydraulic
conditions
in
a
distribution
system.

Although
tracer
studies
often
provide
very
good
information,
they
can
be
time
consuming
and
costly.
Conducting
a
tracer
study
solely
for
the
IDSE
SSS
may
not
be
cost
effective.
However,
if
your
system
is
considering
a
tracer
study
for
some
other
purpose
(
e.
g.,
calibrating
a
hydraulic
model),
Example
3.1
Monitoring
Requirements
for
a
Surface
Water
System
Serving
More
Than
10,000
People
If
your
system
is
a
producing
surface
water
system
serving
more
than
10,000
people
using
free
chlorine
for
residual
disinfection,
your
combined
historical
and
new
TTHM
and
HAA5
data
should
represent,
at
minimum:

1)
At
least
eight
sample
sites
per
treatment
plant,
with
at
least
one
representing
a
near
entry
point,
two
representing
average
residence
time
areas,
three
representing
high
TTHM
areas,
and
two
representing
high
HAA5
areas.

1)
At
least
six
TTHM
and
HAA5
sample
results
from
each
site
(
equivalent
to
requirements
for
SMP
monitoring),
with
at
least
one
group
of
samples
collected
during
the
month
of
historical
peak
TTHM
levels
or
high
water
temperature.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
19
consideration
should
be
given
to
using
the
tracer
study
as
a
tool
for
the
IDSE
SSS.
Also,
results
from
previously
conducted
tracer
studies
may
be
very
useful
in
identifying
areas
in
the
distribution
system
with
high
and
average
residence
times.

Tracer
studies
can
be
performed
by
monitoring
the
concentration
of
a
conservative
constituent
(
i.
e.,
a
chemical
that
does
not
degrade
over
time)
through
the
distribution
system.
Chemicals
used
for
tracers
must
not
be
harmful
to
people
or
the
environment.
Tracer
chemicals
can
be
substances
that
are:

°
Specially
injected
or
normally
injected
in
the
water
for
treatment
purposes
(
e.
g.,
hydrofluorosilic
acid
or
sodium
fluoride)

°
Characteristic
of
the
finished
water
(
e.
g.,
hardness,
conductivity)

Before
injecting
any
tracer,
a
baseline
concentration
of
the
tracer
in
the
distribution
system
water
should
be
determined
(
fluoride,
the
most
common
tracer,
may
be
normally
present
in
trace
amounts).
If
your
system
adds
fluoride,
you
can
turn
off
the
fluoride
feed
for
a
period
of
time,
and
monitor
the
resulting
decrease
of
its
concentration
throughout
the
distribution
system.

If
you
do
not
routinely
add
fluoride
to
the
finished
water,
you
can
conduct
tracer
tests
by
injecting
a
small
dose
of
fluoride
(
about
1
mg/
L)
into
the
water
entering
the
distribution
system.
However,
flouride
can
interact
with
the
material
deposited
inside
pipes
and
storage
facilities
which
reduces
the
accuracy
of
the
calculated
residence
times.
As
a
result,
you
must
inject
sufficient
fluoride
to
meet
the
"
fluoride
demand"
of
your
distribution
system
while
assuring
that
fluoride
concentrations
in
the
distribution
system
do
not
exceed
allowable
concentrations
of
4
mg/
L
(
the
primary
MCL
for
fluoride
is
4
mg/
L
and
the
secondary
MCL
which
is
non­
enforceable
is
2
mg/
L).
If
other
tracers
are
used
such
as
calcium
chloride
or
sodium
chloride,
State
environmental
agencies
may
require
that
food
grade
chemicals
are
used
or
that
other
assurances
are
made
concerning
the
safety
of
the
tracer.
With
some
tracer
chemicals,
systems
may
want
to
consider
notifying
sensitive
users.

When
selecting
tracer
monitoring
locations,
you
should
consider
the
following:

°
Major
intersections
or
branches
in
large
transmission
mains
°
Branches
in
minor
mains
where
flow
is
split
between
two
or
more
groups
of
customers
°
Storage
tanks
°
Entry
points
to
large
commercial
or
industrial
users
°
Sites
prior
to
the
last
fire
hydrant
in
remote
areas
with
few
customers
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
20
To
adequately
characterize
distribution
system
residence
time,
tracer
concentrations
must
be
measured
frequently
and
in
relatively
close
proximity
to
one
another.
The
frequency
of
sampling
will
determine
the
accuracy
of
the
study
results.
For
example,
if
sampling
is
conducted
every
8
hours,
the
water
age
at
a
given
site
will
only
be
accurate
to
within
8
hours.
Furthermore,
the
proximity
of
sample
sites
to
one
another
will
also
affect
the
accuracy
of
the
study
results.
It
may
be
appropriate
to
space
samples
far
apart
on
large
transmission
mains,
but
within
the
distribution
system
(
which
contains
many
piping
and
hydraulic
interactions),
samples
should
be
located
more
closely
together.

The
following
are
general
guidelines
for
using
a
tracer
study
as
part
of
a
SSS:

°
In
general,
the
tracer
study
should
reflect
the
existing
distribution
system
configuration
and
should
have
been
conducted
within
the
last
10
years.
If
permanent
and
significant
changes
to
demand,
piping,
pumping,
or
storage
have
occurred
since
the
tracer
study
was
completed,
the
study
may
not
be
suitable
for
an
SSS.

°
The
tracer
study
should
generally
represent
conditions
of
high
DBP
formation
potential
and
high
water
age
(
typically
summer
months
and
low
demand
periods
for
most
systems).

°
The
tracer
study
should
be
detailed
enough
to
provide
good
characterization
of
water
residence
time
for
the
entire
distribution
system.
Not
all
extremities
must
be
covered
by
the
study,
but
the
data
should
be
complete
enough
to
allow
for
a
reasonable
extrapolation
of
the
results
to
cover
the
entire
distribution
system.

°
If
the
tracer
study
does
not
provide
residence
time
information
for
the
extremities
of
the
distribution
system,
then
historical
TTHM
and
HAA5
data
should
be
reviewed
if
available,
or
new
data
should
be
collected
at
expected
representative
high
TTHM
and
HAA5
sites.

°
Regardless
of
the
level
of
detail
of
the
tracer
study,
systems
should
have
historical
data
for
at
least
one
complete
round
of
sampling
at
the
preliminary
sites
or
should
perform
at
least
one
new
round
of
sampling
at
the
preliminary
sites
(
see
section
3.4.3
for
guidance
on
conducting
one
round
of
sampling).
At
a
minimum,
one
round
of
sampling
should
occur
during
the
month
of
historical
peak
TTHM
levels
or
highest
water
temperature,
if
the
historical
peak
TTHM
month
is
unknown.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
21
3.6
Selecting
Stage
2B
Compliance
Monitoring
Sites
Using
SSS
Results
This
section
describes
procedures
for
using
results
of
an
SSS
to
select
Stage
2B
compliance
monitoring
sites.
Tables
3.1
and
3.2
summarize
the
Stage
2B
monitoring
requirements
for
producing
and
100
percent
purchasing
systems,
respectively
(
Chapter
1
also
provides
this
information).

Section
3.6.1
addresses
selection
of
high
TTHM
and
high
HAA5
sites,
while
Section
3.6.2
addresses
selection
of
average
residence
time
Stage
2B
sites
using
SSS
results
(
note
that
only
a
subset
of
systems
need
to
select
average
residence
time
sites,
as
addressed
in
Section
3.6.2).
Section
3.6.3
provides
examples
of
site
selection.
Appendix
K
contains
an
example
IDSE
report
where
a
hydraulic
model
was
used
to
select
Stage
2B
compliance
sites,
and
Appendix
J
contains
an
example
IDSE
report
where
historical
data
were
used
to
select
Stage
2B
compliance
sites.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
22
Table
3.1
Stage
2B
Plant­
based
Compliance
Monitoring
Requirements
for
Producing
Systems1,2
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
type
of
site)
per
Plant4
Total
Number
of
Sites
per
Plant
Monitoring
Frequency5
Stage
1
Average
Residence
Time
Highest
TTHM
Highest
HAA5
Surface
Water
Systems6
<
500
­
1
1
27
Every
365
days
500
­
9,999
­
1
1
2
Every
90
days
>
10,000
1
2
1
4
Every
90
days
Ground
Water
Systems
<
500
­
1
1
27
Every
365
days
500
­
9,999
­
1
1
2
Every
365
days
>
10,000
­
1
1
2
Every
90
days
1
(
40
CFR
141.605
(
a))

2
For
the
purpose
of
this
guidance
manual,
producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
3
Population
served
is
typically
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
4
For
the
purposes
of
the
Stage
2
DBPR
compliance
monitoring,
a
consecutive
system
entry
point
that
operates
for
at
least
60
consecutive
days
per
year
must
be
considered
a
plant
(
40
CFR
141.601(
d)).
5
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
site,
unless
otherwise
noted.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
site.
6
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
7
Dual
sample
sets
are
not
required
at
both
the
high
TTHM
and
the
high
HAA5
site
 
if
the
highest
TTHM
and
HAA5
levels
occur
at
a
different
site,
then
only
one
sample
is
collected
at
each
site.
If
they
occur
at
the
same
site,
then
a
dual
sample
set
is
collected
at
that
site.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
23
Table
3.2
Stage
2B
Population­
based
Compliance
Monitoring
Requirements
for
100
Percent
Purchasing
Systems1,2
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
type
of
site)
per
System
Total
Number
of
Sites
per
System
Monitoring
Frequency4
Stage
1
Average
Residence
Time
Highest
TTHM
Highest
HAA5
Surface
Water
Systems5
<
500
­
1
1
26
Every
365
days
500
­
4,999
­
1
1
26
Every
90
days
5,000
­
9,999
­
1
1
2
Every
90
days
10,000
­
24,999
1
2
1
4
Every
90
days
25,000
­
49,999
1
3
2
6
Every
90
days
50,000
­
99,999
2
4
2
8
Every
90
days
100,000
­
499,999
3
6
3
12
Every
90
days
500,000
­
1,499,999
4
8
4
16
Every
90
days
1.5
million
­
<
5
million
5
10
5
20
Every
90
days
>
5
million
6
12
6
24
Every
90
days
Ground
Water
Systems
<
500
­
1
1
26
Every
365
days
500
­
9,999
­
1
1
2
Every
365
days
10,000
­
99,999
1
2
1
4
Every
90
days
100,000
­
499,999
1
3
2
6
Every
90
days
>
500,000
2
4
2
8
Every
90
days
1
(
40
CFR
141.605
(
e))

2
For
the
purpose
of
this
guidance
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.
3
Population
served
is
typically
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
4
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
site,
unless
otherwise
noted.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
site.
5
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
6
Dual
sample
sets
are
not
required
at
both
the
high
TTHM
and
the
high
HAA5
site
 
if
the
highest
TTHM
and
HAA5
levels
occur
at
a
different
site,
then
only
one
sample
is
collected
at
each
site.
If
they
occur
at
the
same
site,
then
a
dual
sample
set
is
collected
at
that
site.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
24
3.6.1
Selecting
High
TTHM
and
HAA5
Sites
Selection
Using
a
Historical
Data
SSS
The
following
steps
detail
how
Stage
2B
sites
should
generally
be
selected
based
on
historical
TTHM
and
HAA5
data.
These
steps
also
apply
to
systems
using
a
combination
of
historical
and
new
data.

1)
Calculate
the
Locational
Running
Annual
Average
(
LRAA)
for
TTHM
and
HAA5
concentrations
at
each
historical
data
site.
Historical
data
should
cover
at
least
1
full
year.
If
your
data
covers
a
longer
period,
calculate
separate
annual
averages
for
each
full
year.
Select
the
data
for
the
year
with
highest
average
for
each
site
(
see
the
example
in
Appendix
L
for
sample
calculations).

2)
Calculate
the
LRAA
for
TTHM
and
HAA5
concentrations
at
the
Stage
1
DBPR
maximum
residence
time
site(
s).
If
your
data
covers
more
than
1
year,
calculate
separate
averages
for
each
full
year.
Select
the
data
for
the
year
with
highest
average
for
each
site.

3)
Select
high
TTHM
and
high
HAA5
sites
starting
with
the
highest
TTHM
and
HAA5
LRAAs
from
both
the
Stage
1
DBPR
compliance
monitoring
sites
and
historical
data
sites.

TTHM
and
HAA5
LRAAs
are
the
most
important
factors
to
consider
when
selecting
Stage
2B
monitoring
sites.
However,
the
Stage
2
DBPR
allows
for
some
flexibility
in
selecting
Stage
2B
compliance
sites.
Other
factors
should
be
considered
and
may
lead
to
selecting
a
site
with
a
slightly
lower
LRAA
over
another
site.
The
following
conditions
are
possible
reasons
why
you
may
select
a
site
with
a
lower
LRAA
over
another
site:

°
The
site
provides
for
more
complete
geographic
coverage
of
the
entire
distribution
system
°
The
site
allows
you
to
maintain
an
historical
record
°
Sampling
at
that
site
provides
the
opportunity
to
collect
other
water
quality
or
operational
data
(
e.
g.,
chloramine
systems
may
want
to
collect
nitrate
data
at
that
site)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
2
The
Stage
2
DBPR
does
not
specify
a
difference
between
two
LRAAs
that
allows
selection
of
a
site
with
the
lower
LRAA
for
Stage
2B.
EPA
recognizes
there
is
uncertainty
and
variability
associated
with
the
TTHM
and
HAA5
data
quality.
While
the
LRAA
calculation
reduces
the
impact
of
these
to
some
extent,
they
can
cause
a
small
difference
between
two
LRAAs
to
be
statistically
insignificant
and
thus,
making
the
selection
of
the
Stage
2B
site
dependent
on
other
factors.
The
intent
of
the
Stage
2
DBPR
is
to
reduce
peak
DBP
concentrations
in
the
distribution
system.
You
should
use
best
professional
judgment
to
select
Stage
2B
sites
with
consideration
to
the
intent
of
the
rule
and
demonstrate
to
the
State
the
reason
for
the
selection.
.

July
2003
­
Proposal
Draft
All
Systems
3­
25
If
you
do
not
use
your
highest
TTHM
and
HAA5
LRAAs
to
select
your
Stage
2B
sites,
you
must
provide
justification
for
your
selection
in
your
IDSE
report
(
40
CFR
141.605).
2
Selection
Using
a
Water
Distribution
System
Model
SSS
The
first
step
in
selecting
Stage
2B
sites
is
to
compare
the
model­
predicted
residence
times
for
your
preliminary
sites
with
the
TTHM
and
HAA5
concentrations
from
the
one
round
of
sampling,
Stage
1
compliance
monitoring
results,
and
any
other
historical
TTHM
and
HAA5
data.
Are
the
results
consistent?
In
other
words,
do
those
sites
with
the
highest
residence
time
also
represent
those
sites
with
the
highest
TTHM
concentrations?

Ideally,
the
preliminary
or
Stage
1
DBPR
sites
with
the
highest
TTHM
and
HAA5
sampling
results
should
be
selected
as
the
Stage
2B
high
TTHM
and
high
HAA5
sites.
However,
TTHM
and
HAA5
data
collected
during
the
one
round
of
sampling
at
preliminary
sites
may
not
represent
typical
levels.
Distribution
conditions
at
the
time
of
sampling
should
be
taken
into
account.
EPA
recognizes
that
one
round
of
samples
reflects
only
a
snapshot
of
the
distribution
system.
Modeled
data
represent
a
more
comprehensive
picture
of
the
distribution
system,
and
therefore,
may
not
agree
with
the
sampling
results.
If
your
modeled
data
and
sampling
results
do
not
agree
and
you
select
a
site
based
on
modeled
results,
you
should
explain
your
rationale
for
selecting
that
site
in
your
IDSE
report.

For
example,
say
that
a
model
predicts
that
"
Site
A"
normally
receives
water
from
the
West
Tank
during
the
daytime
hours.
The
TTHM
and
HAA5
results
from
Site
A
were
much
lower
than
expected,
compared
to
other
sites.
Upon
reviewing
the
tank
operating
data
from
the
day
of
sampling,
it
is
likely
that
the
site
was
not
receiving
water
from
the
West
Tank
during
the
time
of
sampling
due
to
low
system
demand
that
day.
In
this
situation,
the
system
may
want
to
select
Site
A
as
a
Stage
2B
compliance
monitoring
site
based
on
the
modeled
data
and
noting
in
the
IDSE
report
the
discrepancy
between
modeled
data
and
sample
results.

You
should
also
consider
other
factors
such
as
geographic
coverage
when
selecting
sites.
It
is
acceptable
to
pick
a
site
with
a
slightly
lower
TTHM
or
HAA5
result
over
another
if
the
selected
site
provides
better
geographic
coverage;
however,
you
must
provide
your
rationale
for
selection
in
the
IDSE
report.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
3
100
percent
purchasing
ground
water
systems
serving
at
least
10,000
people
were
not
required
to
have
average
residence
time
sites
for
Stage
1
DBPR.
100
percent
purchasing
surface
water
systems
may
have
an
average
residence
time
Stage
1
DBPR
site,
depending
on
the
monitoring
plan
for
their
combined
distribution
system.

July
2003
­
Proposal
Draft
All
Systems
3­
26
3.6.2
Selecting
Average
Residence
Time
Sites
The
following
systems
are
required
to
select
average
residence
time
site(
s)
for
the
Stage
2B
(
40
CFR
141.605):

°
100
percent
purchasing
surface
water
or
ground
water
systems
serving
at
least
10,000
people
°
Producing
surface
water
systems
serving
at
least
10,000
people.

One
of
the
purposes
of
the
Stage
2B
average
residence
time
site
is
to
ensure
that
a
historical
data
record
of
system
DBP
levels
is
maintained
(
i.
e.,
systems
keep
one
site
the
same
from
Stage
1
to
Stage
2
DBPR).
Producing
systems
can
meet
this
goal
by
selecting
their
Stage
2B
average
residence
time
site
from
their
three
Stage
1
DBPR
average
residence
time
sites
(
guidelines
for
selecting
from
Stage
1
DBPR
compliance
monitoring
sites
are
provided
below).
100
percent
purchasing
systems
may
not
have
average
residence
time
sites
under
the
Stage
1
DBPR
requirements.
3
In
these
situations,
they
must
alternate
between
high
HAA5
and
high
TTHM
sites
to
fill
the
required
number
of
Stage
1
average
residence
time
sites.

Producing
Systems
Systems
must
select
their
Stage
2B
average
residence
time
site
(
one
per
plant)
from
the
three
existing
Stage
1
DBPR
average
residence
time
sites.
Stage
2B
average
residence
time
sites
should
have
the
highest
TTHM
or
highest
HAA5
LRAA
among
the
Stage
1
DBPR
average
residence
time
sites,
considering
the
most
recent
year
of
data.
If
the
high
TTHM
and
high
HAA5
LRAAs
do
not
occur
at
the
same
site,
consider
other
factors
such
as
geographical
coverage
and
how
close
LRAAs
are
to
the
MCLs,
in
order
to
decide
between
the
two
sites.
Considering
the
second
situation,
if
the
high
TTHM
LRAA
is
70
µ
g/
L
and
high
HAA5
LRAA
is
35
µ
g/
L,
then
the
site
with
the
high
TTHM
LRAA
is
the
better
choice.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
27
3.6.3
Examples
of
Stage
2B
Site
Selection
This
section
provides
examples
of
Stage
2B
site
selection:

Example
3.2
Selecting
Stage
2B
Sites
from
Historical
Data
Example
3.3
Maintaining
an
Historical
Record
Example
3.4
Providing
Geographical
Coverage
When
Choosing
Stage
2B
Sites
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
28
Example
3.2
Selecting
Stage
2B
Sites
from
Historical
Data
A
producing
water
system
serves
90,000
people
and
has
one
surface
water
treatment
plant.
This
system
must
select
4
Stage
2B
compliance
sites:
2
high­
TTHM
sites;
1
high­
HAA5
site;
and
1
from
the
3
existing
Stage
1
DBPR
average
residence
time
compliance
sites.
The
table
below
lists
the
TTHM
and
HAA5
LRAAs
for
all
Stage
1
DBPR
compliance
monitoring
sites
and
three
of
the
eight
historical
sites
(
these
data
represent
the
seven
highest
TTHM
and
HAA5
LRAAs).

Site
TTHM
LRAAs
HAA5
LRAAs
A
(
Stage
1
max.
residence
time)
70
(
1st
year)
,
69
(
2nd
year)
51
(
1st
year),
49
(
2nd
year)

B
(
historical
high
TTHM
site)
66
(
1st
year),
64(
2nd
year)
40
(
1st
year),
38
(
2nd
year)

C
(
historical
high
HAA5
site)
72
(
1st
year),
71
(
2nd
year)
53
(
1st
year),
50
(
2nd
year)

D
(
historical
high
TTHM
site)
76
(
1st
year),
72
(
2nd
year)
50
(
1st
year),
49
(
2nd
year)

E
(
Stage
1
avg.
residence
time)
57
48
F
(
Stage
1
avg.
residence
time)
42
30
G
(
Stage
1
avg.
residence
time)
55
50
Selecting
the
Average
Residence
Time
Site
The
average
residence
time
site
should
have
either
the
highest
TTHM
or
highest
HAA5
LRAA
of
the
Stage
1
DBPR
average
residence
time
sites.
The
water
system
may
choose
either
Site
E
(
highest
TTHM
LRAA)
or
Site
G
(
highest
HAA5
LRAA).
With
two
valid
options,
the
site
providing
the
best
geographic
coverage
is
preferred.
Site
G
is
located
downstream
of
an
elevated
tank
and
is
the
only
site
that
receives
water
from
that
tank;
therefore,
the
water
system
selects
Site
G.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
29
Example
3.2
Selecting
Stage
2B
Sites
from
Historical
Data
(
cont.)

Selecting
the
High­
TTHM
Sites
Site
D
has
the
highest
TTHM
LRAA.
Therefore,
this
site
is
chosen
as
the
first
of
the
high­
TTHM
sites.
Site
C
has
the
next
highest
TTHM
LRAA,
and
Site
A
has
a
slightly
lower
TTHM
LRAA
than
Site
C.
The
difference
in
the
TTHM
values
between
Site
A
and
Site
C
is
minimal,
and
Site
A
is
a
Stage
1
DBPR
"
maximum
compliance"
site.
Because
the
difference
between
the
TTHM
LRAAs
of
Site
A
and
C
are
minimal,
and
Site
A
would
maintain
a
historic
record
of
sampling,
Site
A
is
chosen
as
the
second
high­
TTHM
site.

Selecting
the
High­
HAA5
Site
Site
C
has
the
highest
HAA5
LRAA.
Sites
A
and
D
have
almost
as
high
HAA5
LRAAs.
However,
because
Sites
A
and
D
have
already
been
chosen
as
the
high­
TTHM
sites,
Site
C
is
chosen
as
the
high­
HAA5
site.

A
Water
Treatment
Plant
B
C
Example
3.4
Providing
Geographic
Coverage
when
Choosing
Stage
2B
Sites
In
general,
the
two
representative
highest
TTHM
sites
(
per
plant)
should
not
be
from
the
same
area
of
the
distribution
system.
Consider
the
following
example
 
The
two
highest
TTHM
LRAAs
in
the
distribution
system
are
from
adjacent
historical
sample
sites
(
sites
A
and
B).
The
site
with
the
third
highest
TTHM
LRAA
is
on
the
far
side
of
the
distribution
system
(
site
C).
In
this
case,
consider
selecting
sites
A
and
C
or
B
and
C
as
Stage
2B
sites
for
a
broader
geographical
coverage
of
the
distribution
system.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
30
3.7
Reporting
Results
to
the
State
You
are
required
to
include
your
proposed
Stage
2B
compliance
monitoring
sites
in
your
IDSE
report.
At
a
minimum,
your
IDSE
report
must
include:

°
A
schematic
of
the
distribution
system
°
All
studies,
reports,
data,
analytical
results,
and
modeling
to
support
your
SSS
°
All
TTHM
and
HAA5
analytical
results
from
Stage
1
DBPR
compliance
samples
collected
during
the
period
of
the
IDSE
°
Proposed
Stage
2B
compliance
monitoring
sites
with
justification
for
selection
of
each
proposed
site
°
Proposed
month(
s)
during
which
Stage
2B
monitoring
is
to
be
conducted
Example
3.3
Maintaining
an
Historical
Record
A
100%
purchasing
system
serves
4,000
people
and
purchases
all
of
its
water.
This
system
must
select
two
Stage
2B
compliance
sites:
one
high­
TTHM
and
one
high­
HAA5
site.
The
table
below
lists
historical
and
Stage
1
DBPR
compliance
monitoring
results
for
this
system.

Sample
Sites
LRAA
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Historical
#
1
(
High
TTHM)
71
51
Historical
#
2
(
High
TTHM)
65
45
Historical
#
3
(
High
HAA5)
60
53
Stage
1
DBPR
max
residence
time
site
69
51
Because
the
TTHM
LRAA
for
the
Stage
1
DBPR
site
is
only
slightly
lower
than
the
maximum
TTHM
LRAA
(
Historical
#
1),
the
system
chooses
the
Stage
1
DBPR
site
over
Historical
#
1
for
the
Stage
2B
high
TTHM
site
to
maintain
the
historic
DBP
record
at
that
site.
Historical
#
3
is
selected
as
the
high
HAA5
site
because
this
site
has
the
highest
HAA5
LRAA.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
3­
31
Example
reports
for
SSSs
are
in
appendices
to
this
manual,
as
listed
in
Table
3.3.

Table
3.3
Example
IDSE
Reports
Appendix
System
Characteristics
Appendix
K
SSS
for
a
System
Using
a
Hydraulic
Model
Appendix
L
SSS
for
a
System
Using
Historical
Data
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
1
For
the
purposes
of
this
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.

2
The
Stage
2
DBPR
defines
a
combined
distribution
system
as
the
totality
of
the
distribution
systems
of
wholesale
systems
and
of
the
consecutive
systems
that
receive
finished
water
from
those
wholesale
systems
(
40
CFR
141.2).

July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
1
4.0
Standard
Monitoring
Program
Requirements
for
100
Percent
Purchasing
Systems
4.1
Introduction
This
chapter
describes
the
Initial
Distribution
System
Evaluation
(
IDSE)
Standard
Monitoring
Program
(
SMP)
requirements
for
100
percent
purchasing
systems.
1
IDSE
and
Stage
2B
Disinfectants
and
Disinfection
Byproducts
Rule
(
DBPR)
monitoring
requirements
for
100
percent
purchasing
systems
are
based
on
population
served
and
source
water
type,
not
on
the
number
of
plants
as
under
the
Stage
1
DBPR.
Since
these
systems
do
not
have
treatment
plants,
a
population­
based
monitoring
program
is
more
practical
than
the
alternative
method
of
determining
the
number
of
plants
by
the
number
of
entry
points.

The
SMP
requirements
presented
in
this
chapter
include
monitoring
frequency,
sample
sites,
and
schedules.
Chapter
8
builds
on
this
chapter
by
describing
how
to
select
SMP
monitoring
sites.
Chapter
8
also
describes
how
SMP
results
are
used
to
select
Stage
2B
DBPR
compliance
monitoring
sites
and
lists
the
minimum
requirements
for
the
IDSE
SMP
report.
The
remainder
of
this
chapter
is
organized
as
follows:

4.2
Schedule
for
Conducting
the
SMP
4.3
SMP
Monitoring
Requirements
4.4
Timing
of
Sample
Collection
4.5
Sampling
Protocol
Although
some
guidance
in
this
chapter
is
appropriate
for
other
system
types,
this
chapter
solely
addresses
100
percent
purchasing
systems
.
Refer
to
Chapters
5
through
7
for
guidance
directed
towards
systems
that
produce
some
or
all
of
their
finished
water.

4.2
Schedule
for
Conducting
the
SMP
All
systems
conducting
the
SMP
must
prepare
an
IDSE
report.
Systems
must
either
submit
their
report
[
2
years
after
rule
promulgation]
if
they
are
on
the
early
schedule,
or
[
4
years
after
rule
promulgation]
if
they
are
on
the
late
schedule.
The
schedule
is
based
on
population
of
the
largest
system
in
the
combined
distribution
system.
2
Section
1.1
describes
how
systems
determine
when
their
IDSE
report
is
due
(
i.
e.,
if
they
are
on
the
large
or
small
system
schedule).
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
2
It
is
recommended
that
systems
begin
SMP
planning
no
later
than
18
months
before
their
IDSE
report
is
due
to
the
State.
The
18
months
allows
for
3
months
of
planning,
12
months
of
SMP
sampling,
and
3
months
for
analyzing
the
final
round
of
samples,
reviewing
the
results,
choosing
the
new
compliance
sites,
and
completing
the
IDSE
report.
Table
4.1
shows
IDSE
report
due
dates
and
the
latest
recommended
SMP
sampling
start
dates
for
systems
on
the
early
and
late
schedules.

Table
4.1
Consecutive
System
IDSE
Report
Schedule
Schedule
Type1
IDSE
Report
Due
Date2
Recommended
SMP
Sampling
Start
Date
Figure
of
Schedule
(
on
next
page)

Early
Schedule
[
2
years
after
rule
promulgation]
No
later
than
[
9
months
after
rule
promulgation]
Figure
4.1
Early
System
Late
Schedule
[
4
years
after
rule
promulgation]
No
later
than
[
2
years
and
9
months
after
rule
promulgation]
Figure
4.2
Late
System
1
See
section
1.1
to
determine
your
schedule
type.
2
40
CFR
141.600(
c).

To
ensure
smooth
execution
of
an
SMP,
systems
should
begin
planning
several
months
(
at
least
three
months
is
recommended)
before
the
first
sample
date.
A
written
SMP
sample
plan
must
be
prepared
before
systems
begin
sampling.
An
SMP
plan
must
be
submitted
with
the
IDSE
report
and
include,
at
a
minimum:

°
The
number
of
required
sample
sites
°
The
specific
site
of
all
selected
SMP
sample
sites
°
The
rationale
for
selection
of
SMP
sample
sites
(
not
required,
but
recommended)

°
A
sampling
schedule
Figures
4.1
and
4.2
show
the
latest
dates
by
which
systems
should
begin
planning,
sampling,
and
preparing
the
report
for
an
IDSE
SMP.
Figure
4.1
presents
the
early
schedule
and
Figure
4.2
presents
the
late
schedule.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
3
23
22
21
20
19
1
18
17
16
15
14
13
12
11
10
9
8
7
6
24
5
4
3
2
Submit
IDSE
Report
to
State/
Primacy
Agency
Rule
Promulgation
[
Actual
Timeline
to
be
provided]
Start
SMP
Monitoring
1
Year
of
Monitoring
Begin
Planning
for
IDSE
SMP
Start
Preparing
Report
[
Year
2]
[
Year
1]

[
Year
4]
[
Year
3]
[
Year
1
and
2]
Submit
IDSE
Report
to
State/
Primacy
Agency
Rule
Promulgation
[
Actual
Timeline
to
be
provided]
Start
SMP
Monitoring
1
Year
of
Monitoring
Begin
Planning
for
IDSE
SMP
Start
Preparing
Report
47
46
45
44
43
42
41
40
39
38
37
48
35
34
33
32
31
30
29
28
27
26
25
36
Figure
4.1
Early
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)

Figure
4.2
Late
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
3
For
the
purposes
of
this
guidance
manual,
surface
water
systems
are
the
same
as
subpart
H
systems
 
they
use
surface
water
or
ground
water
under
the
direct
influence
of
surface
water
(
GWUDI)
as
a
source.
Surface
water
systems
include
all
mixed
systems
(
i.
e.,
those
that
use
surface
and
ground
water).
Ground
water
systems
are
those
that
use
only
ground
water
as
a
source.

July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
4
Stage
1
DBPR
compliance
monitoring
sites
cannot
be
used
as
SMP
sites.
4.3
SMP
Monitoring
Requirements
Table
4.2
summarizes
the
number
of
sites,
sampling
frequency,
and
total
number
of
samples
that
must
be
collected
for
100
percent
purchasing
surface
and
ground
water
systems3
(
40
CFR
141.602(
a)
and
(
b)).
The
number
of
sites
and
samples
is
based
on
the
population
of
the
system.
All
of
a
system's
IDSE
SMP
samples
must
be
dual
samples
sets,
meaning
one
total
trihalomethane
(
TTHM)
and
one
five
haloacetic
acids
(
HAA5)
sample
that
is
taken
at
the
same
time
and
location.
Chapter
8
provides
guidance
for
selecting
SMP
sites
to
meet
the
requirements
of
the
IDSE.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
5
Table
4.2
SMP
Sampling
Requirements
for
100
Percent
Purchasing
Systems1
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
location
type)
per
System
Total
Number
of
Sites
per
System
Monitoring
Frequency
for
the
1­
year
IDSE
Period5
Near
Entry
Point4
Average
Residence
Time
High
TTHM
High
HAA5
Surface
Water
Systems6
<
500
­
­
1
1
2
Every
180
days
500
­
4,999
­
­
1
1
2
Every
90
days
5,000
­
9,999
­
1
2
1
4
Every
90
days
10,000
­
24,999
1
2
3
2
8
Every
60
days
25,000
­
49,999
2
3
4
3
12
Every
60
days
50,000
­
99,999
3
4
5
4
16
Every
60
days
100,000
­
499,999
4
6
8
6
24
Every
60
days
500,000
­
<
1.5
million
6
8
10
8
32
Every
60
days
1.5
million
­
<
5
million
8
10
12
10
40
Every
60
days
>
5
million
10
12
14
12
48
Every
60
days
Ground
Water
Systems
<
500
­
­
1
1
2
Every
180
days
500
­
9,999
­
­
1
1
2
Every
90
days
10,000
­
99,999
1
1
2
2
6
Every
90
days
100,000
­
499,999
1
1
3
3
8
Every
90
days
>
500,000
2
2
4
4
12
Every
90
days
1
(
40
CFR
141.602
(
b))
2
For
the
purposes
of
this
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.
3
Population
served
is
typically
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.

4
See
section
8.2
for
requirements
when
the
number
of
entry
points
in
a
system
is
different
from
the
number
of
required
near­
entry
point
sites
in
this
table.
5
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
6
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
6
0
10
20
30
40
50
60
70
80
90
Jan­
01
Feb­
01
Mar­
01
Apr­
01
May­
01
Jun­
01
Jul­
01
Aug­
01
Sep­
01
Oct­
01
Nov­
01
Dec­
01
Jan­
02
Feb­
02
Mar­
02
Apr­
02
May­
02
Jun­
02
Jul­
02
Month
Highest
Distribution
System
DBP
Concentration
(
ug/
L)

0
10
20
30
40
50
60
70
80
TTHM
HAA5
Temperature
(
F)
Average
Distribution
System
Temperature
(
degrees
Fahrenheit)
Highest
DBP
value
occurred
in
June
4.4
Timing
of
Sample
Collection
A
system's
monitoring
schedule
must
be
determined
using
historical
disinfection
byproduct
(
DBP)
data
or
temperature
data
(
40
CFR
141.602(
a)).
DBP
data
should
be
used
as
the
primary
indicator,
and
then
temperature
data
if
DBP
data
are
not
sufficient.
The
month
with
the
highest
TTHM
or
HAA5
concentration
(
whichever
of
the
two
is
highest)
or
maximum
temperature
is
referred
to
as
the
controlling
month.

Systems
may
select
any
date
in
the
controlling
month
to
sample
and
should
consider
dates
when
staff
are
available
to
collect
samples.
The
other
rounds
of
sampling
must
be
scheduled
around
the
controlling
month
at
the
required
sampling
frequency
listed
in
Table
4.2.
The
sampling
dates
for
the
entire
year
must
be
scheduled
and
documented
in
the
system's
sampling
plan
before
collecting
the
first
sample.
Systems
can
select
a
start
date
prior
to
the
controlling
month
provided
the
controlling
month
is
included
in
their
schedule.
Figure
4.3
and
Table
4.3
provides
an
example
of
how
to
select
the
controlling
month
using
hypothetical
distribution
system
data.

Figure
4.3
Example
Historic
DBP
and
Temperature
Data
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
7
Table
4.3
Example
of
Historic
DBP
and
Temperature
Data
Month
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)
Average
Distribution
System
Temp.
(
F)

Mar.
2001
41
15
48
Apr.
2001
52
May
2001
55
June
2001
82
31
65
July
2001
73
Aug.
2001
71
Sept.
2001
64
36
70
Oct.
2001
60
Nov.
2001
53
Dec.
2001
40
32
50
Jan.
2002
48
Feb.
2002
46
Mar.
2002
45
50
50
Apr.
2002
52
May
2002
56
June
2002
67
23
60
In
this
example,
the
highest
DBP
level
was
the
TTHM
value
from
June
2001.
Therefore
the
controlling
month
is
June
and
the
IDSE
SMP
sampling
must
be
scheduled
to
include
that
month.
If
no
DBP
data
were
available,
July
would
have
been
selected
as
the
controlling
month
because
it
has
the
highest
average
distribution
system
temperature.

In
the
example,
if
the
system
must
monitor
quarterly,
using
the
data
in
Figure
4.3
and
Table
4.3
the
four
sampling
dates
should
be
scheduled
approximately
every
90
days
considering
June
as
the
controlling
month
as
follows:

°
First
Tuesday
in
March
2003
°
First
Tuesday
in
June
2003
(
controlling
month)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
8
°
First
Tuesday
in
September
2003
°
First
Tuesday
in
December
2003
Chloramine
systems
that
routinely
convert
to
free
chlorine
for
a
"
burnout
period"
must
still
set
their
schedules
according
to
the
highest
DBP
(
or
temperature)
month
(
40
CFR
141.602(
a)),
regardless
of
whether
chloramine
or
free
chlorine
is
used
during
the
controlling
month.

SMP
samples
should
be
collected
as
scheduled.
EPA
recognizes
extenuating
circumstances
can
occur
that
may
delay
sampling
(
e.
g.,
an
ice
storm).
Any
deviations
from
the
scheduled
sampling
days
must
be
noted
in
the
IDSE
report
(
40
CFR
141.604(
a)).

4.5
Sampling
Protocol
Generally,
it
is
best
to
collect
samples
in
the
morning
to
allow
the
samples
to
be
packed
and
shipped
the
same
day
if
systems
are
sending
them
to
a
contract
laboratory.
Samples
should
be
collected
in
a
manner
that
ensures
they
are
representative
of
the
water
in
the
distribution
system
at
that
sampling
point.
If
sampling
from
indoor
plumbing,
samples
should
be
collected
from
the
cold
water
line.
The
line
between
the
sample
tap
or
faucet
and
the
distribution
system
should
be
flushed.
This
can
usually
be
accomplished
by
opening
the
faucet
where
the
sample
is
collected
and
allowing
the
water
to
run
for
a
few
minutes.
When
the
water
temperature
stabilizes,
this
indicates
fresh
water
from
the
distribution
system
is
being
obtained.

The
sample
bottles
should
contain
appropriate
dechlorinating
agents/
preservatives
prior
to
filling.
Sampling
and
storage
protocols
outlined
in
the
approved
analytical
methods
must
be
followed.
Contact
the
laboratory
analyzing
the
samples
for
their
recommended
sampling
and
preservation
protocols.
Appendix
C
provides
more
detailed
information
on
sampling
procedures
and
approved
sampling
methods.
Samples
must
be
analyzed
by
laboratories
that
have
received
certification
by
EPA
or
the
State.

If
a
sample
is
lost
or
broken,
take
a
replacement
sample
as
soon
as
possible.
Systems
only
need
to
resample
for
the
lost
sample
bottle;
they
do
not
need
to
resample
the
entire
set.
For
example,
if
a
TTHM
sample
is
broken
during
shipping,
the
system
would
resample
only
for
TTHM
as
soon
as
possible
at
the
given
site.
Make
sure
to
note
the
deviation
in
sampling
schedule
for
this
sample
in
the
IDSE
report.

Sampling
near
Fire
Hydrants
Fire
hydrants
or
blow­
offs
in
locations
that
could
impact
the
water
reaching
a
sampling
point
should
not
be
flushed
prior
to
the
collection
of
the
DBP
samples,
because
that
could
significantly
change
the
"
age"
of
the
water
being
sampled.
The
intent
of
the
DBP
sampling
effort
is
to
obtain
water
that
is
representative
of
what
the
customers
normally
receive.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
100
Percent
Purchasing
Systems
4­
10
Continue
to
Chapter
8
 
SMP
Site
Selection
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
1
For
the
purpose
of
this
guidance
manual,
producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
See
Chapter
1
for
additional
guidance
on
classifying
systems.

2
For
the
purposes
of
this
guidance
manual,
surface
water
systems
are
the
same
as
"
subpart
H"
systems
 
they
use
surface
water
or
ground
water
under
the
direct
influence
of
surface
water
(
GWUDI)
as
a
source.
Surface
water
systems
include
all
mixed
systems
(
i.
e.,
those
that
use
surface
and
ground
water).
Ground
water
systems
are
those
that
use
only
ground
water
as
a
source.

July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
1
5.0
Standard
Monitoring
Program
Requirements
for:

Producing
Surface
Water
Systems
Serving
at
Least
10,000
People
5.1
Introduction
This
chapter
describes
the
Initial
Distribution
System
Evaluation
(
IDSE)
Standard
Monitoring
Program
(
SMP)
requirements
for
producing
surface
water
systems1,
2
serving
at
least
10,000
people.
These
requirements
include
monitoring
frequency,
sample
sites,
and
scheduling.
Chapter
8
builds
on
this
chapter
by
describing
how
final
SMP
monitoring
sites
should
be
selected
using
various
sources
and
tools.
Chapter
8
also
describes
how
SMP
results
are
used
to
select
Stage
2B
Disinfectants
and
Disinfection
Byproducts
Rule
(
DBPR)
compliance
monitoring
sites
and
lists
the
minimum
requirements
for
the
IDSE
SMP
report.
The
remainder
of
this
section
is
organized
as
follows:

5.2
Schedule
for
Conducting
the
SMP
5.3
Number
of
Samples
Required
5.4
Sample
Site
Requirements
5.5
Timing
of
SMP
Sample
Collection
5.6
Sampling
Protocol
Although
some
guidance
in
this
chapter
is
appropriate
for
other
system
types
and
sizes,
this
chapter
specifically
addresses
producing
surface
water
systems
serving
at
least
10,000
people.
Refer
to
Chapters
6
and
7
for
guidance
directed
towards
other
producing
system
types.
Refer
to
Chapter
4
for
guidance
directed
towards
100
percent
purchasing
systems.

5.2
Schedule
for
Conducting
the
SMP
All
surface
water
systems
serving
at
least
10,000
people
are
on
the
large
system
schedule
and
must
submit
their
IDSE
report
[
2
years
after
rule
promulgation].
It
is
recommended
that
systems
begin
planning
their
SMP
no
later
than
[
6
months
after
rule
promulgation].
The
18
months
includes
3
months
for
planning,
12
months
of
SMP
sampling,
and
3
months
to
analyze
the
final
round
of
samples,
review
the
results,
choose
the
new
compliance
sites,
and
complete
the
IDSE
report.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
2
23
22
21
20
19
1
18
17
16
15
14
13
12
11
10
9
8
7
6
24
5
4
3
2
Submit
IDSE
Report
to
State/
Primacy
Agency
Rule
Promulgation
[
Actual
Timeline
to
be
provided]
Start
SMP
Monitoring
1
Year
of
Monitoring
Begin
Planning
for
IDSE
SMP
Start
Preparing
Report
[
Year
2]
[
Year
1]
To
ensure
smooth
execution
of
an
SMP,
systems
should
begin
planning
several
months
(
at
least
three
months
is
recommended)
before
the
first
sample
date.
A
written
SMP
sample
plan
must
be
prepared
before
beginning
sampling.
The
plan
must
be
submitted
with
the
IDSE
report
and
include,
at
a
minimum:

°
The
number
of
required
sample
sites
°
The
specific
site
of
all
selected
SMP
sample
sites
°
The
rationale
for
selection
of
SMP
sample
sites
(
not
required
but
recommended)

°
A
sampling
schedule
Figure
5.1
shows
the
latest
recommended
dates
by
which
systems
should
begin
planning,
sampling,
and
preparing
the
report
for
an
SMP
to
meet
regulatory
requirements.

Figure
5.1
Large
System
Schedule
for
Conducting
the
SMP
(
Showing
Latest
Recommended
Start
Dates)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
3
Approximately
Every
60
Days
for
1
Year
HAA5
TTHM
5.2.1
Consecutive
Water
Systems
and
Wholesalers
The
IDSE
SMP
report
is
due
at
the
same
time
as
that
of
the
largest
system
in
the
combined
distribution
system.
Therefore,
if
a
small
system
serving
less
than
10,000
people
buys
water
from
a
system
serving
at
least
10,000
people,
they
must
submit
their
report
on
the
large
system
schedule,
or
[
2
years
after
rule
promulgation].
EPA
recommends
that
systems
share
information
about
their
IDSE
report
schedule
with
all
wholesale
purchasers
of
their
water.
Coordination
with
systems
that
purchase
water
from
systems
serving
at
least
10,000
people
is
not
required,
but
is
strongly
recommended.

5.3
Number
of
Samples
Required
Producing
surface
water
systems
serving
at
least
10,000
people
must
collect
samples
every
2
months
over
a
1
year
period.
Samples
must
be
collected
at
eight
sites
per
plant
and
analyzed
for
total
trihalomethanes
(
TTHM)
and
five
haloacetic
acids
(
HAA5).
These
sites
must
be
different
than
the
Stage
1
DBPR
compliance
monitoring
sites.
All
systems'
IDSE
SMP
samples
must
be
dual
samples
sets,
meaning
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
For
a
system
with
one
plant,
a
total
of
48
dual
sample
sets
are
required
during
the
1­
year
monitoring
period
(
see
the
illustration
below).

8
Sites
per
plant
×
6
Sample
Periods
=
48
Dual
Samples
Sets
Section
1.1
provides
guidelines
for
estimating
the
number
or
plants
in
a
system.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
4
***
Examples
for
Determining
Number
of
Plants,
Sites,
and
Samples***

Example
5.1
A
system
serving
100,000
people
operates
one
surface
water
treatment
plant
and
receives
water
from
two
disinfecting
ground
water
systems,
at
separate
entry
points,
for
more
than60
consecutive
days
per
year.

Total
plants:
3
(
one
surface
water
and
two
ground
water)
Total
SMP
sites:
8
sites
per
plant
×
3
plants
=
24
sites
Total
Samples:
24
sties
×
6
sample
periods
=
144
dual
samples
Example
5.2
A
system
serving
35,000
people
purchases
treated
surface
water
through
one
entry
point
and
has
three
wells.
Chlorine
is
added
at
each
well
site.
The
State
determined
that
two
of
the
wells
draw
from
the
same
aquifer
and
that
the
third
well
draws
from
a
different
aquifer.

Total
plants:
3
(
one
for
the
purchased
water
entry
point,
the
second
for
the
two
wells
drawing
from
the
same
aquifer,
and
the
third
for
the
well
drawing
from
another
aquifer)
Total
sites:
8
sites
per
plant
×
3
plants
=
24
sites
Total
Samples:
24
sites
×
6
sample
periods
=
144
dual
samples
Example
5.3
A
system
serves
90,000
people,
purchases
treated
water
from
one
wholesaler,
through
five
entry
points,
and
has
two
wells
which
they
use
on
a
daily
basis.
The
wholesaler
has
three
surface
water
treatment
plants.
Three
of
the
entry
points
receive
water
from
plant
A
and
two
of
the
entry
points
receive
water
from
plant
B.
The
State­
approved
multiple
consecutive
entry
points
to
be
considered
as
one
plant
 
the
three
entry
points
receiving
water
from
plant
A
are
one
plant
and
the
two
entry
points
receiving
water
from
plant
B
are
a
second
plant.
The
two
wells
feed
into
one
pumphouse
where
chlorine
is
added;
this
is
considered
one
treatment
plant.

Total
plants:
3
(
two
plants
for
the
consecutive
entry
points
and
one
ground
water)
Total
SMP
sites:
8
sites
per
plant
×
3
plants
=
24
sites
Total
Samples:
24
sites
×
6
sample
periods
=
144
dual
samples
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
5
Stage
1
DBPR
compliance
monitoring
sites
cannot
be
used
as
SMP
sites.

P
u
r
c
h
a
s
e
d
W
a
t
e
r
E
n
t
r
y
P
o
i
n
t
#
1
P
u
r
c
h
a
s
e
d
W
a
t
e
r
E
n
t
r
y
P
o
i
n
t
#
2
S
u
r
f
a
c
e
W
a
t
e
r
T
r
e
a
t
m
e
n
t
P
l
a
n
t
5.4
Sample
Site
Requirements
Sample
site
requirements
depend
on
a
system's
residual
disinfectant
type.
Table
5.1
summarizes
the
SMP
site
requirements
for
producing
surface
water
systems
serving
at
least
10,000
people.
The
required
SMP
sample
sites
listed
in
Table
5.1
are
in
addition
to
Stage
1
DBPR
compliance
monitoring
sites.
Chapter
8
describes
how
real
entry
point
sites
are
selected
for
chlorine
and
chloramine
systems
and
provides
guidance
for
selecting
all
other
SMP
sites
to
meet
the
requirements
of
the
IDSE.

Table
5.1
SMP
Sample
Sites
for
Producing
Surface
Water
Systems
Serving
at
Least
10,000
People
Residual
Disinfectant
Type
Number
of
SMP
Sample
Sites
Required
per
Plant
Near
Entry
Point
Average
Residence
Time
High
TTHM
High
HAA5
Total
Dual
Samples
per
Plant
Chlorine
1
2
3
2
8
Chloramines
2
2
2
2
8
5.4.1
Changing
Disinfectants
During
the
SMP
Period
If
systems
anticipate
a
change
in
residual
disinfectant
during
the
1­
year
SMP
sampling
period,
selection
of
SMP
sites
should
be
based
on
the
disinfectant
expected
to
be
in
use
at
the
end
of
the
sampling
period.
Figure
5.2
shows
an
example
timeline
where
a
system
uses
free
chlorine
at
the
start
of
the
SMP,
but
changes
to
chloramines
before
the
end
of
the
SMP
sampling
period.
In
this
case,
sample
site
selection
should
be
performed
as
required
for
chloraminated
systems.
Thus,
two
sample
sites
(
instead
of
one)
near
the
entry
point
and
four
sites
(
instead
of
five)
representative
of
highest
TTHM
and
HAA5
should
be
selected.
In
both
cases,
two
average
residence
time
sites
are
required.

If
systems
are
unsure
as
to
whether
their
disinfectant
conversion
will
take
place
during
the
SMP
sampling
period,
they
should
select
sites
based
on
SMP
requirements
for
a
chlorine
system.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
6
SMP
Sampling
Period
Months
Planned
Conversion
to
Chloramines
SMP
must
be
based
on
chloramine
requirements.
23
22
21
20
19
1
18
17
16
15
14
13
12
11
10
9
8
7
6
24
5
4
3
2
Rule
Promulgation
Figure
5.2
Planned
Conversion
to
Chloramines
5.5
Timing
of
SMP
Sample
Collection
A
system's
monitoring
schedule
must
be
determined
using
historical
disinfection
byproduct
(
DBP)
data
or
temperature
data
(
40
CFR
141.602(
a)).
DBP
data
should
be
used
as
the
primary
indicator,
and
then
temperature
data
if
DBP
data
are
not
sufficient.
The
month
with
the
highest
TTHM
or
HAA5
concentration
(
whichever
of
the
two
is
highest)
or
maximum
temperature
is
referred
to
as
the
controlling
month.

Systems
may
select
any
date
in
the
controlling
month
to
sample
and
should
consider
dates
when
staff
are
available
to
collect
samples.
The
other
rounds
of
sampling
must
be
scheduled
around
the
controlling
month
at
two
month
intervals.
The
sampling
dates
for
the
entire
year
must
be
scheduled
and
documented
in
the
system's
sampling
plan
before
collecting
the
first
sample.
Systems
can
select
a
start
date
prior
to
the
controlling
month
provided
the
controlling
month
is
included
in
their
schedule.
Figure
5.3
and
Table
5.2
provides
an
example
of
how
to
select
the
controlling
month
using
hypothetical
distribution
system
data.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
7
0
10
20
30
40
50
60
70
80
90
Sep­
00
Oct­
00
Nov­
00
Dec­
00
Jan­
01
Feb­
01
Mar­
01
Apr­
01
May­
01
Jun­
01
Jul­
01
Aug­
01
Sep­
01
Oct­
01
Nov­
01
Dec­
01
Jan­
02
Feb­
02
Mar­
02
Apr­
02
May­
02
Jun­
02
Month
Highest
Distribution
System
DBP
Concentration
(
ug/
L)

0
10
20
30
40
50
60
70
80
90
Average
Distribution
System
Temperature
(
degrees
F)

TTHM
HAA5
Temperature
(
F)
Highest
DBP
value
occurred
in
July
Figure
5.3
Example
Historic
DBP
and
Temperature
Data
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
8
Table
5.2
Example
of
Historic
DBP
and
Temperature
Data
Month
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)
Average
Distribution
System
Temp.
(
F)

Nov.
2000
50
Dec.
2000
43
Jan
2001
43
29
40
Feb
2001
43
Mar.
2001
45
Apr.
2001
62
45
50
May
2001
60
June
2001
70
July
2001
85
42
74
Aug.
2001
78
Sept.
2001
70
Oct.
2001
55
38
60
Nov.
2001
49
Dec.
2001
42
Jan.
2002
48
32
40
Feb.
2002
41
Mar.
2002
44
Apr.
2002
50
53
48
May
2002
62
In
this
example,
the
highest
DBP
level
was
the
TTHM
value
from
July
2001.
Therefore,
the
controlling
month
is
July
and
the
SMP
sampling
must
be
scheduled
considering
that
month.
If
no
DBP
data
were
available,
August
would
have
been
selected
as
the
controlling
month
because
it
has
the
highest
average
distribution
system
temperature.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
9
For
the
example
in
Figure
5.3
and
Table
5.2,
the
six
sampling
dates
should
be
scheduled
approximately
every
60
days
with
July
as
the
controlling
month
as
follows:

°
First
Thursday
in
March
2003
°
First
Thursday
in
May
2003
°
First
Thursday
in
July
2003
(
controlling
month)

°
First
Thursday
in
September
2003
°
First
Thursday
in
November
2003
°
First
Thursday
in
January
2004
Chloramine
systems
that
routinely
convert
to
free
chlorine
for
a
"
burnout
period"
must
still
set
their
schedules
according
to
the
highest
DBP
(
or
temperature)
month
(
40
CFR
141.602(
a)),
regardless
of
whether
chloramine
or
free
chlorine
is
used
during
the
controlling
month.

SMP
samples
should
be
collected
as
scheduled.
EPA
recognizes
extenuating
circumstances
can
occur
that
may
delay
sampling
(
e.
g.,
an
ice
storm).
Any
deviations
from
the
scheduled
sampling
days
must
be
noted
in
the
IDSE
report
(
40
CFR
141.604(
a)).

5.6
Sampling
Protocol
Generally,
it
is
best
to
collect
samples
in
the
morning
to
allow
the
samples
to
be
packed
and
shipped
the
same
day
if
systems
are
sending
them
to
a
contract
laboratory.
Samples
should
be
collected
in
a
manner
that
ensures
they
are
representative
of
the
water
in
the
distribution
system
at
that
sampling
point.
If
sampling
from
indoor
plumbing,
samples
should
be
collected
from
the
cold
water
line.
The
line
between
the
sample
tap
or
faucet
and
the
distribution
system
should
be
flushed.
This
can
usually
be
accomplished
by
opening
the
faucet
where
the
sample
is
collected
and
allowing
the
water
to
run
for
a
few
minutes.
When
the
water
temperature
stabilizes,
this
indicates
fresh
water
from
the
distribution
system
is
being
obtained.

The
sample
bottles
should
contain
appropriate
dechlorinating
agents/
preservatives
prior
to
filling.
Sampling
and
storage
protocols
outlined
in
the
approved
analytical
methods
must
be
followed.
Contact
the
laboratory
analyzing
the
samples
for
their
recommended
sampling
and
preservation
protocols.
Appendix
C
provides
more
detailed
information
on
sampling
procedures
and
approved
sampling
methods.
Samples
must
be
analyzed
by
laboratories
that
have
received
certification
by
EPA
or
the
State.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Surface
Water
Systems
(>
10,000)
5­
10
Continue
to
Chapter
8
 
SMP
Site
Selection
If
a
sample
is
lost
or
broken,
take
a
replacement
sample
as
soon
as
possible.
Systems
need
to
resample
only
for
the
lost
sample
bottle;
they
do
not
need
to
resample
the
entire
set.
For
example,
if
a
TTHM
sample
is
broken
during
shipping,
systems
would
resample
only
for
TTHM
as
soon
as
possible
at
the
given
site.
Make
sure
to
note
the
deviation
in
sampling
schedule
for
this
sample
in
the
IDSE
report.

Sampling
near
Fire
Hydrants
Fire
hydrants
or
blow­
offs
in
locations
that
could
impact
the
water
reaching
a
sampling
point
should
not
be
flushed
prior
to
the
collection
of
the
DBP
samples,
because
that
could
significantly
change
the
"
age"
of
the
water
being
sampled.
The
intent
of
the
DBP
sampling
effort
is
to
obtain
water
that
is
representative
of
what
the
customers
normally
receive.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
1
For
the
purpose
of
this
guidance
manual,
producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
See
Chapter
1
for
additional
guidance
on
classifying
systems.

2
For
the
purposes
of
this
guidance
manual,
surface
water
systems
are
the
same
as
"
subpart
H"
systems
 
they
use
surface
water
or
ground
water
under
the
direct
influence
of
surface
water
(
GWUDI)
as
a
source.
Surface
water
systems
include
all
mixed
systems
(
i.
e.,
those
that
use
surface
and
ground
water).
Ground
water
systems
are
those
that
use
only
ground
water
as
a
source.

July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
1
6.0
Standard
Monitoring
Program
Requirements
for:

Producing
Surface
Water
Systems
Serving
500
to
9,999
People
or
Producing
Ground
Water
Systems
Serving
at
Least
10,000
People
6.1
Introduction
This
chapter
describes
the
Initial
Distribution
System
Evaluation
(
IDSE)
Standard
Monitoring
Program
(
SMP)
requirements
for
producing
surface
water
systems
1,
2
serving
500
to
9,999
people
and
producing
ground
water
systems
serving
at
least
10,000.
These
requirements
include
monitoring
frequency,
sample
sites,
and
schedules.
Chapter
8
builds
on
this
chapter
by
describing
how
to
select
SMP
monitoring
sites.
Chapter
8
also
describes
how
SMP
results
are
used
to
select
Stage
2B
Disinfectants
and
Disinfection
Byproducts
Rule
(
DBPR)
compliance
monitoring
sites
and
lists
the
minimum
requirements
for
the
IDSE
SMP
report.
The
remainder
of
this
chapter
is
organized
as
follows:

6.2
Schedule
for
Conducting
the
SMP
6.3
SMP
Monitoring
Requirements
6.4
Timing
of
Sample
Collection
6.5
Sampling
Protocol
Although
some
guidance
in
this
chapter
is
appropriate
for
other
system
types
and
sizes,
this
chapter
specifically
addresses
producing
surface
water
systems
serving
500
to
9,999
people
and
producing
ground
water
systems
serving
at
least
10,000
people.
100
percent
purchasing
systems
should
refer
to
Chapter
4,
and
producing
systems
of
other
source
water
types
and
system
sizes
should
refer
to
Chapters
5
and
7.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
3
The
Environmental
Protection
Agency
(
EPA)
defines
a
combined
distribution
system
as
the
totality
of
the
distribution
systems
of
wholesale
systems
and
of
the
consecutive
systems
that
receive
finished
water
from
those
wholesale
systems.

July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
2
23
22
21
20
19
1
18
17
16
15
14
13
12
11
10
9
8
7
6
24
5
4
3
2
Submit
IDSE
Report
to
State/
Primacy
Agency
Rule
Promulgation
[
Actual
Timeline
to
be
provided]
Start
SMP
Monitoring
1
Year
of
Monitoring
Begin
Planning
for
IDSE
SMP
Start
Preparing
Report
[
Year
2]
[
Year
1]
6.2
Schedule
for
Conducting
the
SMP
All
systems
conducting
the
SMP
must
prepare
an
IDSE
report.
Systems
must
either
submit
their
report
[
2
years
after
rule
promulgation]
if
they
are
on
the
large
system
schedule,
or
[
4
years
after
rule
promulgation]
if
they
are
on
the
small
system
schedule.
The
schedule
is
based
on
population
of
the
largest
system
in
the
combined
distribution
system.
3
Section
1.4
describes
how
systems
determine
when
their
IDSE
report
is
due
(
i.
e.,
if
they
are
on
the
large
or
small
system
schedule).

It
is
recommended
that
systems
begin
planning
the
SMP
no
later
than
18
months
before
the
IDSE
report
is
due
to
the
State.
The
18
months
includes
3
months
of
planning,
12
months
of
SMP
sampling,
and
3
months
for
analyzing
the
final
round
of
samples,
reviewing
the
results,
choosing
the
new
compliance
sites,
and
completing
the
IDSE
report.
Figures
6.1
and
6.2
show
the
latest
recommended
dates
by
which
systems
should
begin
planning,
sampling,
and
preparing
the
report
for
an
SMP
to
meet
regulatory
requirements.
Figure
6.1
represents
the
large
system
schedule
and
Figure
6.2
represents
the
small
system
schedule.

Figure
6.1
Large
System
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
3
[
Year
4]
[
Year
3]
[
Year
1
and
2]
Submit
IDSE
Report
to
State/
Primacy
Agency
Rule
Promulgation
[
Actual
Timeline
to
be
provided]
Start
SMP
Monitoring
1
Year
of
Monitoring
Begin
Planning
for
IDSE
SMP
Start
Preparing
Report
47
46
45
44
43
42
41
40
39
38
37
48
35
34
33
32
31
30
29
28
27
26
25
36
Stage
1
DBPR
compliance
monitoring
sites
cannot
be
used
as
SMP
sites.
Figure
6.2
Small
System
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)

A
written
SMP
sample
plan
must
be
prepared
before
systems
begin
sampling.
The
plan
must
be
submitted
with
the
IDSE
report
and
include,
at
a
minimum:

°
The
number
of
required
sample
sites
°
The
specific
site
of
each
selected
SMP
sample
site
°
The
rationale
for
selection
of
SMP
sample
sites
(
not
required,
but
recommended)

°
A
sampling
schedule
6.3
SMP
Monitoring
Requirements
Table
6.1
summarizes
the
number
of
sites,
sampling
frequency,
and
total
number
of
samples
that
must
be
collected
per
plant
in
a
system
(
this
sampling
requirement
is
in
addition
to
the
Stage
1
DBPR
compliance
monitoring).
All
of
a
system's
IDSE
SMP
samples
must
be
dual
sample
sets,
meaning
one
total
trihalomethane
(
TTHM)
and
one
five
haloacetic
acids
(
HAA5)
sample
that
is
taken
at
the
same
time
and
location.
The
SMP
sample
sites
are
in
addition
to
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
4
TTHM
Approximately
Every
90
Days
HAA5
Stage
1
DBPR
compliance
monitoring
sites
(
40
CFR
141.602(
a)).
Chapter
8
provides
guidance
for
selecting
SMP
sites
to
meet
the
requirements
of
the
IDSE.

Table
6.1
Summary
of
SMP
Sampling
Requirements1
Source
Type
and
Population
Served
Number
of
Sites
Sampling
Frequency
Total
Dual
Samples
per
Plant
Surface
Water
(
500
­
9,999)
and
Ground
Water
(>
10,000)
2
per
plant
 
1
high
TTHM
and
1
high
HAA5
every
3
months
for
1
year
8
1
40
CFR
141.602(
a))

For
producing
surface
water
systems
serving
500
to
9,999
people
and
ground
water
systems
serving
at
least
10,000
people
and
having
one
plant,
a
total
of
8
dual
sample
sets
is
required,
and
each
must
be
analyzed
for
TTHM
and
HAA5
(
see
the
illustration
below).

2
Sites
per
Plant
×
4
Sample
Periods
=
8
Dual
Samples
Sets
Section
1.1
provides
guidelines
for
estimating
the
number
or
plants
in
a
system.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
5
***
Examples
for
Determining
Number
of
Plants,
Sites,
and
Samples***

Example
6.1
A
system
serving
6,000
people
operates
one
surface
water
treatment
plant
and
receives
water
from
two
other
surface
water
systems,
at
separate
entry
points,
for
more
than
60
consecutive
days
per
year.

Total
plants:
3
(
one
surface
water
and
two
consecutive
entry
points)
Total
SMP
sites:
2
sites
per
plant
×
3
plants
=
6
sites
Total
samples:
6
sites
×
4
monitoring
periods
=
24
dual
sample
sets
Example
6.2
A
system
serves
5,000
people,
purchases
treated
surface
water
through
one
entry
point,
and
has
three
wells.
Chlorine
is
added
at
each
well
site.
The
State
determined
that
two
of
the
wells
draw
from
the
same
aquifer
and
that
the
third
well
draws
from
a
different
aquifer.

Total
plants:
3
(
one
for
the
purchased
water
entry
point,
the
second
for
the
two
wells
drawing
from
the
same
aquifer,
and
the
third
for
the
well
drawing
from
another
aquifer)
Total
sites:
2
sites
per
plant
×
3
plants
=
6
sites
Total
samples:
6
sites
×
4
monitoring
periods
=
24
dual
sample
sets
Example
6.3
A
system
serves
25,000
people,
purchases
treated
ground
water
from
one
wholesaler,
through
five
entry
points,
and
has
two
wells.
The
State
approved
multiple
consecutive
entry
points
to
be
considered
as
one
plant
 
the
three
entry
points
receiving
water
from
plant
A
are
one
plant
and
the
two
entry
points
receiving
water
from
plant
B
are
a
second
plant.
The
two
wells
feed
into
one
pumphouse
where
chlorine
is
added;
this
is
considered
one
treatment
plant.

Total
plants:
3
(
two
plants
for
the
consecutive
entry
points
and
one
ground
water)
Total
SMP
sites:
2
sites
per
plant
×
3
plants
=
6
sites
Total
samples:
6
sites
×
4
monitoring
periods
=
24
dual
sample
sets
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
6
6.4
Timing
of
Sample
Collection
A
system's
monitoring
schedule
must
be
determined
using
historical
disinfection
byproduct
(
DBP)
data
or
temperature
data
(
40
CFR
141.602(
a)).
DBP
data
should
be
used
as
the
primary
indicator,
and
then
temperature
data
if
DBP
data
are
not
sufficient.
The
month
with
the
highest
TTHM
or
HAA5
concentration
(
whichever
of
the
two
is
highest)
or
maximum
temperature
is
referred
to
as
the
controlling
month.

Systems
may
select
any
date
in
the
controlling
month
to
sample
and
should
consider
dates
when
staff
are
available
to
collect
samples.
The
other
rounds
of
sampling
must
be
scheduled
around
the
controlling
month
at
three
month
intervals.
The
sampling
dates
for
the
entire
year
must
be
scheduled
and
documented
in
a
system's
sampling
plan
before
collecting
the
first
sample.
Systems
can
select
a
start
date
prior
to
the
controlling
month
provided
the
controlling
month
is
included
in
their
schedule.
Figure
6.3
and
Table
6.2
provide
an
example
of
how
to
select
the
controlling
month
using
hypothetical
distribution
system
data.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
7
0
10
20
30
40
50
60
70
80
90
Jan­
01
Feb­
01
Mar­
01
Apr­
01
May­
01
Jun­
01
Jul­
01
Aug­
01
Sep­
01
Oct­
01
Nov­
01
Dec­
01
Jan­
02
Feb­
02
Mar­
02
Apr­
02
May­
02
Jun­
02
Jul­
02
Month
Highest
Distribution
System
DBP
Concentration
(
ug/
L)

0
10
20
30
40
50
60
70
80
TTHM
HAA5
Temperature
(
F)
Average
Distribution
System
Temperature
(
degrees
Fahrenheit)
Highest
DBP
value
occurred
in
June
Figure
6.3
Example
Historic
DBP
and
Temperature
Data
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
8
Table
6.2
Example
of
Historic
TTHM
and
Temperature
Data
Month
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)
Average
Distribution
System
Temp.
(
F)

Mar.
2001
41
15
48
Apr.
2001
52
May
2001
55
June
2001
82
31
65
July
2001
73
Aug.
2001
71
Sept.
2001
64
36
70
Oct.
2001
60
Nov.
2001
53
Dec.
2001
40
32
50
Jan.
2002
48
Feb.
2002
46
Mar.
2002
45
50
50
Apr.
2002
52
May
2002
56
June
2002
67
23
60
In
this
example,
the
highest
DBP
level
was
the
TTHM
value
from
June
2001.
Therefore,
the
controlling
month
is
June
and
the
SMP
sampling
must
be
scheduled
to
include
that
month.
If
no
DBP
data
were
available,
July
would
have
been
selected
as
the
controlling
month
because
it
has
the
highest
average
distribution
system
temperature.

In
the
example,
if
the
system
must
monitor
quarterly,
using
the
data
in
Figure
6.3
and
Table
6.2,
the
four
sampling
dates
should
be
scheduled
approximately
every
90
days
considering
June
as
the
controlling
month
as
follows:

°
First
Monday
in
March
2003
°
First
Monday
in
June
2003
(
controlling
month)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
9
°
First
Monday
in
September
2003
°
First
Monday
in
December
2003
Chloramine
systems
that
routinely
convert
to
free
chlorine
for
a
"
burnout
period"
must
still
set
their
schedules
according
to
the
highest
DBP
(
or
temperature)
month
(
40
CFR
141.602(
a)),
regardless
of
whether
chloramine
or
free
chlorine
is
used
during
the
controlling
month.

SMP
samples
should
be
collected
as
scheduled.
EPA
recognizes
extenuating
circumstances
can
occur
that
may
delay
sampling
(
e.
g.,
an
ice
storm).
Any
deviations
from
the
scheduled
sampling
days
must
be
noted
in
the
IDSE
report
(
40
CFR
141.604(
a)).

6.5
Sampling
Protocol
Generally,
it
is
best
to
collect
samples
in
the
morning
to
allow
the
samples
to
be
packed
and
shipped
the
same
day
if
systems
are
sending
them
to
a
contract
laboratory.
Samples
should
be
collected
in
a
manner
that
ensures
they
are
representative
of
the
water
in
the
distribution
system
at
that
sampling
point.
If
sampling
from
indoor
plumbing,
samples
should
be
collected
from
the
cold
water
line.
The
line
between
the
sample
tap
or
faucet
and
the
distribution
system
should
be
flushed.
This
can
usually
be
accomplished
by
opening
the
faucet
where
the
sample
is
collected
and
allowing
the
water
to
run
for
a
few
minutes.
When
the
water
temperature
stabilizes,
this
indicates
fresh
water
from
the
distribution
system
is
being
obtained.

The
sample
bottles
should
contain
appropriate
dechlorinating
agents/
preservatives
prior
to
filling.
Sampling
and
storage
protocols
outlined
in
the
approved
analytical
methods
must
be
followed.
Contact
the
laboratory
analyzing
the
samples
for
their
recommended
sampling
and
preservation
protocols.
Appendix
C
provides
more
detailed
information
on
sampling
procedures
and
approved
sampling
methods.
Samples
must
be
analyzed
by
laboratories
that
have
received
certification
by
EPA
or
the
State.

If
a
sample
is
lost
or
broken,
take
a
replacement
sample
as
soon
as
possible.
Systems
need
to
resample
only
for
the
lost
sample
bottle;
they
do
not
need
to
resample
the
entire
set.
For
example,
if
a
TTHM
sample
is
broken
during
shipping,
the
system
would
resample
only
for
TTHM
as
soon
as
possible
at
the
given
site.
Make
sure
to
note
the
deviation
in
sampling
schedule
for
this
sample
in
the
IDSE
report.

Sampling
near
Fire
Hydrants
Fire
hydrants
or
blow­
offs
in
sites
that
could
impact
the
water
reaching
a
sampling
point
should
not
be
flushed
prior
to
the
collection
of
the
DBP
samples,
because
that
could
significantly
change
the
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
Producing
Systems
SW
(
500­
9,999)
and
GW
(>
10,000)
6­
10
Continue
to
Chapter
8
 
SMP
Site
Selection
"
age"
of
the
water
being
sampled.
The
intent
of
the
DBP
sampling
effort
is
to
obtain
water
that
is
representative
of
what
the
customers
normally
receive.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
1
For
the
purpose
of
this
guidance
manual,
producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
See
Chapter
1
for
additional
guidance
on
classifying
systems.

2
For
the
purposes
of
this
guidance
manual,
surface
water
systems
are
the
same
as
"
subpart
H"
systems
 
they
use
surface
water
or
ground
water
under
the
direct
influence
of
surface
water
(
GWUDI)
as
a
source.
Surface
water
systems
include
all
mixed
systems
(
i.
e.,
those
that
use
surface
and
ground
water).
Ground
water
systems
are
those
that
use
only
ground
water
as
a
source.

July
2003
Proposal
Draft
Producing
Systems
SW
(<
500)
and
GW
(<
10,000)
7­
1
7.0
Standard
Monitoring
Program
Requirements
for:

Producing
Surface
Water
Systems
Serving
Less
Than
500
People
or
Producing
Ground
Water
Systems
Serving
Less
Than
10,000
People
7.1
Introduction
This
chapter
describes
the
Initial
Distribution
System
Evaluation
(
IDSE)
Standard
Monitoring
Program
(
SMP)
requirements
for
producing
surface
water
systems1,
2
serving
less
than
500
people
and
producing
ground
water
systems
serving
less
than
10,000
people.
These
requirements
include
monitoring
frequency,
sample
sites,
and
schedules.
Chapter
8
builds
on
this
chapter
by
describing
how
to
select
SMP
monitoring
sites.
Chapter
8
also
describes
how
SMP
results
are
used
to
select
Stage
2B
Disinfectants
and
Disinfection
Byproducts
Rule
(
DBPR)
compliance
monitoring
sites
and
lists
the
minimum
requirements
for
the
IDSE
SMP
report.
The
remainder
of
this
chapter
is
organized
as
follows:

7.2
Schedule
for
Conducting
the
SMP
7.3
Number
of
Samples
Required
7.4
Sample
Site
Requirements
7.5
Timing
of
Sample
Collection
7.6
Sampling
Protocol
Although
some
guidance
in
this
chapter
is
appropriate
for
other
system
types
and
sizes,
this
chapter
specifically
addresses
producing
surface
water
systems
serving
less
than
500
people
and
producing
ground
water
systems
serving
less
than
10,000
people.
100
percent
purchasing
systems
should
refer
to
Chapter
4,
and
producing
systems
of
other
source
water
types
and
system
sizes
should
refer
to
Chapters
5
and
6.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
3
The
Environmental
Protection
Agency
(
EPA)
defines
a
combined
distribution
system
as
the
totality
of
the
distribution
systems
of
wholesale
systems
and
of
the
consecutive
systems
that
receive
finished
water
from
those
wholesale
systems.

July
2003
Proposal
Draft
Producing
Systems
SW
(<
500)
and
GW
(<
10,000)
7­
2
7.2
Schedule
for
Conducting
the
SMP
All
systems
conducting
the
SMP
must
prepare
an
IDSE
report.
Systems
must
either
submit
their
report
[
2
years
after
rule
promulgation]
if
they
are
on
the
large
system
schedule,
or
[
4
years
after
rule
promulgation]
if
they
are
on
the
small
system
schedule.
The
schedule
is
based
on
population
of
the
largest
system
in
the
combined
distribution
system.
3
Section
1.4
describes
how
systems
determine
when
their
IDSE
report
is
due
(
i.
e.,
if
they
are
on
the
large
or
small
system
schedule).

It
is
recommended
that
systems
begin
planning
the
SMP
no
later
than
18
months
before
the
IDSE
report
is
due
to
the
State.
The
18
months
includes
3
months
of
planning,
12
months
of
SMP
sampling,
and
3
months
for
analyzing
the
final
round
of
samples,
reviewing
the
results,
choosing
the
new
compliance
sites,
and
completing
the
IDSE
report.
Table
7.1
shows
IDSE
report
due
dates
and
the
latest
recommended
SMP
sampling
start
dates
for
systems
on
the
small
and
large
system
schedules.

Table
7.1
IDSE
Report
Schedule
Schedule
Type
IDSE
Report
Due
Date
Recommended
SMP
Sampling
Start
Date
Figure
of
Schedule
(
on
next
page)

Large
System
Schedules
[
2
years
after
rule
promulgation]
No
later
than
[
9
months
after
rule
promulgation]
Figure
7.1
Large
System
Small
System
Schedule
[
4
years
after
rule
promulgation]
No
later
than
[
2
years
and
9
months
after
rule
promulgation]
Figure
7.2
Small
System
Note:
See
section
1.4
to
determine
the
schedule
type.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
Proposal
Draft
Producing
Systems
SW
(<
500)
and
GW
(<
10,000)
7­
3
23
22
21
20
19
1
18
17
16
15
14
13
12
11
10
9
8
7
6
24
5
4
3
2
Submit
IDSE
Report
to
State/
Primacy
Agency
Rule
Promulgation
[
Actual
Timeline
to
be
provided]
Start
SMP
Monitoring
1
Year
of
Monitoring
Begin
Planning
for
IDSE
SMP
Start
Preparing
Report
[
Year
2]
[
Year
1]
To
ensure
smooth
execution
of
an
SMP,
systems
should
begin
planning
several
months
(
at
least
three
months
is
recommended)
before
the
first
sample
date.
A
written
SMP
sample
plan
must
be
prepared
before
systems
begin
sampling.
The
plan
must
be
submitted
with
the
IDSE
report
and
include,
at
a
minimum:

°
The
number
of
required
sample
sites
°
The
specific
site
of
all
selected
SMP
sample
sites
°
The
rationale
for
selection
of
SMP
sample
sites
(
not
required,
but
recommended)

°
A
sampling
schedule
Figures
7.1
and
7.2
show
the
latest
dates
by
which
systems
should
begin
planning,
sampling,
and
preparing
the
report
for
an
SMP
to
meet
regulatory
requirements.
Figure
7.1
represents
the
schedule
for
consecutive
systems
with
a
large
system
in
the
combined
distribution
system
and
Figure
7.2
represents
the
small
system
schedule.

Figure
7.1
Large
System
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
Proposal
Draft
Producing
Systems
SW
(<
500)
and
GW
(<
10,000)
7­
4
[
Year
4]
[
Year
3]
[
Year
1
and
2]
Submit
IDSE
Report
to
State/
Primacy
Agency
Rule
Promulgation
[
Actual
Timeline
to
be
provided]
Start
SMP
Monitoring
1
Year
of
Monitoring
Begin
Planning
for
IDSE
SMP
Start
Preparing
Report
47
46
45
44
43
42
41
40
39
38
37
48
35
34
33
32
31
30
29
28
27
26
25
36
TTHM
Once
every
6
months
for
1
year
HAA5
Figure
7.2
Small
System
Schedule
for
Conducting
the
IDSE
SMP
(
Showing
Latest
Recommended
Start
Dates)

7.3
Number
of
Samples
Required
Producing
surface
water
systems
serving
fewer
than
500
people
and
ground
water
systems
serving
fewer
than
10,000
people
must
collect
samples
every
6
months
over
a
1­
year
period
(
this
sampling
requirement
is
in
addition
to
Stage
1
DBPR
monitoring).
Samples
must
be
collected
at
two
sites
per
plant
and
analyzed
for
total
trihalomethane
(
TTHM)
and
five
haloacetic
acids
(
HAA5).
All
of
a
system's
IDSE
SMP
samples
must
be
dual
sample
sets,
meaning
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
For
systems
with
one
plant,
a
total
of
4
dual
sample
sets
are
required,
and
each
should
be
analyzed
for
TTHM
and
HAA5
(
see
the
illustration
below).

2
Sites
per
Plant
×
2
Sample
Periods
=
4
Dual
Sample
Sets
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
Proposal
Draft
Producing
Systems
SW
(<
500)
and
GW
(<
10,000)
7­
5
***
Examples
for
Determining
Number
of
Plants,
Sites,
and
Samples***

Example
7.1
A
system
serves
450
people,
purchases
treated
surface
water
through
one
entry
point,
and
has
two
wells.
Chlorine
is
added
at
each
well
site.
The
State
determined
that
the
two
wells
draw
from
the
same
aquifer.

Total
plants:
2
(
one
for
the
purchased
water
entry
point
and
one
for
the
two
wells
drawing
from
the
same
aquifer)
Total
sites:
2
sites
per
plant
×
2
plants
=
4
sites
Total
samples:
8
samples
Example
7.2
A
system
serves
300
people,
purchases
treated
surface
water
from
one
wholesaler
through
two
entry
points.
The
State
allowed
the
multiple
consecutive
entry
points
to
be
considered
as
one
plant.

Total
plants:
1
(
one
plant
for
both
consecutive
entry
points)
Total
SMP
sites:
2
sites
per
plant
×
1
plant
=
2
sites
Section
1.1.4
provides
guidelines
for
estimating
the
number
or
plants
in
a
system.

7.4
Sample
Site
Requirements
Systems
must
select
two
SMP
sample
sites
per
plant,
meeting
the
following
criteria:

°
One
site
representative
of
the
highest
TTHM
concentration
in
the
system
°
One
site
representative
of
the
highest
HAA5
concentration
in
the
system
°
Sites
must
be
different
than
the
Stage
1
DBPR
monitoring
sites
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
Proposal
Draft
Producing
Systems
SW
(<
500)
and
GW
(<
10,000)
7­
6
Stage
1
DBPR
compliance
monitoring
sites
cannot
be
used
as
SMP
sites.
In
many
small
systems,
the
highest
HAA5
concentration
would
be
expected
to
occur
at
the
same
site
as
the
highest
TTHM
concentration.
However,
in
some
systems
(
often
those
with
low
disinfectant
residual
levels
and
high
maximum
water
age)
the
HAA5
concentration
can
decrease
in
some
parts
of
the
distribution
system,
because
HAA5
can
biodegrade
when
no
residual
disinfectant
is
present.
The
highest
HAA5
site
will
not
be
the
same
as
the
highest
TTHM
site.
As
a
result,
this
situation
is
described
and
help
is
provided.
Chapter
8
provides
guidance
for
selecting
SMP
sites
to
meet
the
requirements
of
the
IDSE.

7.5
Timing
of
Sample
Collection
One
of
the
system's
sampling
dates
must
occur
in
the
month
with
the
highest
water
temperature
in
their
distribution
system
(
systems
should
already
be
taking
the
Stage
1
DBPR
compliance
samples
during
this
month).
The
system's
other
sampling
date
must
be
6
months
before
or
after
the
high
distribution
system
water
temperature
month.
The
6­
month
interval
should
be
maintained
as
closely
as
possible
(
40
CFR
141.602(
a)).

SMP
samples
should
be
collected
as
scheduled.
EPA
recognizes
extenuating
circumstances
can
occur
that
may
delay
sampling
(
e.
g.,
an
ice
storm).
Any
deviations
from
the
scheduled
sampling
days
must
be
noted
in
the
IDSE
report
(
40
CFR
141.604(
a)).

This
regimen
is
expected
to
typically
result
in
one
sample
date
occurring
in
the
summer
(
July
through
September),
and
the
second
in
the
winter
(
January­
March).

7.6
Sampling
Protocol
Generally,
it
is
best
to
collect
samples
in
the
morning
to
allow
the
samples
to
be
packed
and
shipped
the
same
day
if
systems
are
sending
them
to
a
contract
laboratory.
Samples
should
be
collected
in
a
manner
that
ensures
they
are
representative
of
the
water
in
the
distribution
system
at
that
sampling
point.
If
sampling
from
indoor
plumbing,
samples
should
be
collected
from
the
cold
water
line.
The
line
between
the
sample
tap
or
faucet
and
the
distribution
system
should
be
flushed.
This
can
usually
be
accomplished
by
opening
the
faucet
where
the
sample
is
collected
and
allowing
the
water
to
run
for
a
few
minutes.
When
the
water
temperature
stabilizes,
this
indicates
fresh
water
from
the
distribution
system
is
being
obtained.

The
sample
bottles
should
contain
appropriate
dechlorinating
agents/
preservatives
prior
to
filling.
Sampling
and
storage
protocols
outlined
in
the
approved
analytical
methods
must
be
followed.
Contact
the
laboratory
analyzing
the
samples
for
their
recommended
sampling
and
preservation
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
Proposal
Draft
Producing
Systems
SW
(<
500)
and
GW
(<
10,000)
7­
7
Continue
to
Chapter
8
 
SMP
Site
Selection
protocols.
Appendix
C
provides
more
detailed
information
on
sampling
procedures
and
approved
sampling
methods.
Samples
must
be
analyzed
by
laboratories
that
have
received
certification
by
EPA
or
the
State.

If
a
sample
is
lost
or
broken,
take
a
replacement
sample
as
soon
as
possible.
Systems
only
need
to
resample
for
the
lost
sample
bottle;
they
do
not
need
to
resample
the
entire
set.
For
example,
if
a
TTHM
sample
is
broken
during
shipping,
the
system
would
resample
only
for
TTHM
as
soon
as
possible
at
the
given
site.
Make
sure
to
note
the
deviation
in
sampling
schedule
for
this
sample
in
the
IDSE
report.

Sampling
near
Fire
Hydrants
Fire
hydrants
or
blow­
offs
in
locations
that
could
impact
the
water
reaching
a
sampling
point
should
not
be
flushed
prior
to
the
collection
of
the
disinfection
byproduct
(
DBP)
samples,
because
that
could
significantly
change
the
"
age"
of
the
water
being
sampled.
The
intent
of
the
DBP
sampling
effort
is
to
obtain
water
that
is
representative
of
what
the
customers
normally
receive.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
1
Data
Sources
and
Tools
Disinfectant
residual,
maps,
models,
etc.

Select
Preliminary
Sites
Narrow
Down
Selection
Select
Final
Sites
General
Approach
to
SMP
Site
Selection
8.0
Standard
Monitoring
Program
Site
Selection
and
Reporting
8.1
Introduction
Chapters
4
through
7
of
this
manual
provided
detailed
requirements
for
conducting
an
Initial
Distribution
System
Evaluation
(
IDSE)
Standard
Monitoring
Program
(
SMP).
This
chapter,
which
applies
to
all
system
types,
system
sizes,
and
source
water
types,
expands
on
those
chapters
by
providing
technical
guidance
for
selecting
SMP
monitoring
sites
using
various
tools.

The
general
approach
for
selecting
SMP
sites
is
to
use
available
data
sources
and
analysis
tools
to
select
a
large
number
of
potential
sites
(
referred
to
as
preliminary
sites).
From
that
group
of
sites,
systems
should
consider
geographic
coverage
and
other
distribution
system
factors
to
narrow
down
preliminary
sites
to
final
SMP
sites.

This
chapter
is
organized
as
follows:

Background
Information
8.2
Description
of
SMP
Site
Types
8.3
Considerations
for
Systems
with
More
than
One
Plant
or
Entry
Point
8.4
Data
Sources
and
Tools
for
Identifying
Preliminary
SMP
Sites
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
2
SMP
Site
Selection
8.5
Methodology
for
Selecting
Final
SMP
Sites
Stage
2B
Site
Selection
Based
on
SMP
Results
and
Reporting
8.6
Stage
2B
DBPR
Site
Selection
and
IDSE
Reporting
Requirements
8.7
Reporting
Results
to
the
State
8.2
Description
of
SMP
Sample
Site
Types
Tables
8.1
and
8.2
summarize
the
SMP
sample
site
requirements
according
to
system
type,
system
size,
and
source
water
type
(
Chapter
1
also
provides
this
information).
As
shown
in
the
tables,
there
are
four
types
of
sampling
locations
defined
for
the
SMP:
near­
entry
point,
average
residence
time,
high
total
trihalomethane
(
TTHM),
and
high
five
haloacetic
acids
(
HAA5).
Sections
8.2.1
through
8.2.3
provide
descriptions
of
each
type
of
sample
site.
Note
that
all
sample
site
types
are
not
required
for
all
systems
and,
as
stated
in
Chapters
4
through
7,
the
Stage
1
DBPR
compliance
monitoring
sites
cannot
be
used
as
SMP
sites.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
3
Table
8.1
SMP
Sampling
Requirements
for
100
Percent
Purchasing
Systems1,2
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
location
type)
per
System
Total
Number
of
Sites
per
System
Monitoring
Frequency
for
the
1­
year
IDSE
Period5
Near
Entry
Point4
Average
Residence
Time
High
TTHM
High
HAA5
Surface
Water
Systems6
<
500
­
­
1
1
2
Every
180
days
500
­
4,999
­
­
1
1
2
Every
90
days
5,000
­
9,999
­
1
2
1
4
Every
90
days
10,000
­
24,999
1
2
3
2
8
Every
60
days
25,000
­
49,999
2
3
4
3
12
Every
60
days
50,000
­
99,999
3
4
5
4
16
Every
60
days
100,000
­
499,999
4
6
8
6
24
Every
60
days
500,000
­
<
1.5
million
6
8
10
8
32
Every
60
days
1.5
million
­
<
5
million
8
10
12
10
40
Every
60
days
>
5
million
10
12
14
12
48
Every
60
days
Ground
Water
Systems
<
500
­
­
1
1
2
Every
180
days
500
­
9,999
­
­
1
1
2
Every
90
days
10,000
­
99,999
1
1
2
2
6
Every
90
days
100,000
­
499,999
1
1
3
3
8
Every
90
days
>
500,000
2
2
4
4
12
Every
90
days
1
(
40
CFR
141.602
(
b))
2
For
the
purposes
of
this
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.
3
Population
served
is
usually
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.

4
See
section
8.2
for
requirements
when
the
number
of
entry
points
in
a
system
is
different
from
the
number
of
required
near­
entry
point
sites
in
this
table.
5
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location.
6
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
4
Table
8.2
SMP
Sampling
Requirements
for
Producing
Systems1,2
System
Size
(
Population
Served3)
Residual
Disinfectant
Number
of
Distribution
System
Sites
(
by
location
type)
for
each
Plant
Total
Number
of
Sites
per
Plant
Monitoring
Frequency4
Near­
Entry
Point
Average
Residence
Time
High
TTHM
High
HAA5
Surface
Water
Systems5
<
500
Chlorine
or
Chloramines
­
­
1
1
2
Every
180
days
500
­
9,999
Chlorine
or
Chloramines
­
­
1
1
2
Every
90
days
>
10,000
Chlorine
1
2
3
2
8
Every
60
days
Chloramines
2
2
2
2
8
Ground
Water
Systems
<
10,000
Chlorine
or
Chloramines
­
­
1
1
2
Every
180
days
>
10,000
Chlorine
or
Chloramines
­
­
1
1
2
Every
90
days
1
(
40
CFR
141.602(
a))

2
For
the
purpose
of
this
guidance
manual,
producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
3
Population
served
is
usually
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
4
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
5
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).

As
described
in
previous
chapters,
the
monitoring
requirements
for
producing
systems
are
based
on
the
number
of
plants.
The
Stage
2
DBPR
does
not
define
a
plant,
but
does
specify
the
following:

°
Consecutive
system
entry
points
receiving
disinfected
water
for
at
least
60
consecutive
days
must
be
considered
a
plant
(
40
CFR
141.602(
a))

°
Multiple
entry
points
or
multiple
wells
drawing
from
the
same
aquifer
may
be
considered
as
one
plant
(
40
CFR
141.601(
d))
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
5
Example
8.1
Less
Required
than
Entry
Points
in
the
Systems
A
100
percent
purchasing
system
receives
ground
water
from
two
wholesalers
and
serves
300,000
people.
Approximately
70
percent
of
the
system's
water
is
purchased
from
Wholesaler
A,
the
remaining
30
percent
from
Wholesaler
B.
The
IDSE
SMP
requirements
for
this
system
include
one
near­
entry
point
site
(
see
Table
8.1).
This
system
should
locate
its
near­
entry
point
site
near
the
Wholesaler
A
consecutive
system
entry
point.
For
guidance
purposes,
any
location
where
disinfected
water
enters
the
distribution
system
should
be
considered
a
"
plant".
See
Chapter
1,
section
1.1
for
guidance
on
determining
number
of
plants
in
a
system.

8.2.1
Near­
Entry
Point
SMP
Sites
The
rule
does
not
have
specific
location
requirements
for
near
entry
point
sites.
EPA
recommends
locating
these
sites
between
the
treatment
facility
or
consecutive
system
entry
point
and
before
or
near
the
first
customer.
Data
from
this
site
represent
the
minimum
residence
time
and
can
be
used
as
a
baseline
for
interpreting
changes
in
water
quality
as
water
travels
through
the
distribution
system.
DBP
data
from
near­
entry
point
sites
can
also
be
used
to
identify
opportunities
for
improvements
at
the
treatment
plant.

The
next
two
sections
provide
additional
guidance
for
selecting
near­
entry
point
SMP
sites.

8.2.1.1
Near­
Entry
Point
SMP
Sites
for
100
Percent
Purchasing
Systems
As
indicated
in
Table
8.1,
the
number
of
near­
entry
point
sites
required
for
100
percent
purchasing
systems
depends
only
on
the
source
water
type
and
population
served.
As
a
result,
a
situation
may
exist
where
a
system
has
more
or
less
actual
consecutive
system
entry
points
than
the
number
of
near­
entry
points
sites
required
by
Table
8.1
or
Table
8.2.
If
this
occurs,
the
rule
requires
the
following
adjustments
(
40
CFR
141.6022(
b)):

°
If
the
required
number
of
near­
entry
point
SMP
sites
is
less
than
the
actual
number
of
consecutive
system
entry
points,
first
select
sites
at
the
entry
points
delivering
surface
water
in
order
from
the
highest
to
lowest
flow,
then
select
sites
at
the
entry
points
delivering
ground
water,
in
order
from
the
highest
to
lowest
flow,
until
the
required
number
of
SMP
sites
have
been
identified.
(
See
Example
8.1.)

°
If
the
required
number
of
near­
entry
point
SMP
sites
is
more
than
the
actual
number
of
consecutive
system
entry
points,
the
"
excess"
near­
entry
point
sites
must
be
distributed
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
6
A
B
C
D
Your
City
Distribution
System
From
Big
City
WTP
Example
8.3
Multiple
Entry
Points
on
One
Transmission
Line
Your
City
receives
water
from
Big
City
through
a
single
transmission
main
with
multiple
consecutive
system
entry
points
(
A,
B,
C,
and
D)
and
little
difference
in
average
flows.
The
State
has
determined
these
entry
points
are
a
single
source
and
the
estimated
water
age
at
each
entry
point
is
similar.
In
this
case,
A,
B,
C,
or
D
would
be
acceptable
and
should
be
among
high
TTHM
and
high
HAA5
sites
so
that
the
total
number
of
SMP
sites
is
met.
These
excess
sites
must
be
distributed
in
the
order
of
high
TTHM,
high
HAA5
.
(
see
Example
8.2.)

Multiple
Entry
Points
Considered
as
One
Plant
Multiple
consecutive
entry
points
may
be
considered
a
single
plant
with
approval
from
the
State
(
40
CFR
141.601(
d)).
There
is
no
provision
in
the
rule
designating
which
entry
point
must
be
used
to
locate
the
near­
entry
point
site.
A
location
near
any
entry
point
or
prior
to
the
first
group
of
customers
for
any
one
entry
point
should
be
acceptable.
However,
if
the
average
flow
differs
significantly
between
the
entry
points,
you
should
consider
using
the
entry
point
with
the
greatest
flow
to
locate
your
nearentry
point
SMP
site.
(
See
Examples
8.3
and
8.4.)
Example
8.2
Excess
Near­
entry
Point
Site
Requirements
A
100
percent
purchasing
system
receives
surface
water
from
three
wholesalers
and
serves
550,000
people.
The
IDSE
SMP
requirements
for
this
system
include
six
near­
entry
point
sites
(
see
Table
8.1),
but
the
system
has
only
3
consecutive
system
entry
points.
This
system
must
select
3
near­
entry
point
sites.
According
to
the
rule
stated
above,
the
remaining
3
near­
entry
point
sites
would
be
distributed
as
follows:
2
high
TTHM
sites
and
1
high
HAA5
site.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
7
A
B
C
Your
City
Distribution
System
From
Big
City
WTP
Example
8.4
Multiple
Entry
Points
with
Different
Flows
Your
City
receives
water
from
Big
City
at
three
consecutive
system
entry
points
(
A,
B
and
C).
Entry
points
A
and
B
are
branches
of
a
common
main;
entry
point
C
is
off
a
separate
main.
The
State
has
determined
these
entry
points
are
a
single
source
and
the
estimated
water
age
at
each
entry
point
is
similar.
50
percent
of
Your
City's
water
enters
through
A,
20
percent
through
B,
and
30
percent
through
C.
Your
city
selects
a
near­
entry
point
SMP
site
near
A
because
the
majority
of
water
enters
through
this
entry
point.

8.2.1.2
Near­
Entry
Point
SMP
Sites
for
Producing
Systems
The
rule
requires
producing
surface
water
systems
that
serve
at
least
10,000
people
to
select
near­
entry
point
sites
depending
on
the
total
number
of
plants
in
the
system
and
the
residual
disinfectant
type
(
40
CFR
141.602
(
a))
(
see
Table
8.2).

°
Chlorinated
systems
must
select
one
near­
entry
point
SMP
site
per
plant
°
Chloraminated
systems
must
select
two
near­
entry
point
SMP
sites
per
plant
The
requirements
differ
between
chlorinated
systems
and
chloraminated
systems
because
DBP
formation
differs
under
chloraminated
and
chlorinated
conditions.
Chloramine
residuals
are
more
stable
than
chlorine
residuals
and,
therefore,
do
not
react
as
readily
with
organic
compounds
in
the
water.
Based
on
evaluation
of
Information
Collection
Rule
(
ICR)
data,
DBP
concentrations
in
chloraminated
systems
vary
less
throughout
the
distribution
system
than
in
chlorinated
systems.
HAA5,
in
particular,
can
peak
at
or
near
the
entry
point
to
the
distribution
system
in
a
chloraminated
system.
(
Appendix
B
describes
DBP
formation
in
more
detail.)
As
recommended
in
the
beginning
of
section
8.2.1,
any
sites
between
the
treatment
facility
(
or
entry
point)
and
a
first
group
of
customers
should
be
acceptable
for
chloraminated
systems.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
8
Well
#
1
A
B
First
group
of
customers
for
Well
#
1
Well
#
2
First
group
of
customers
for
Well
#
2
Example
8.5
Multiple
Entry
Points
The
system
has
two
wells
which
the
State
determined
were
drawing
from
the
same
aquifer
and
could
be
considered
as
one
plant.
Site
A
or
Site
B
would
be
acceptable
for
their
near­
entry
point
site.
Ground
Water
Wells
or
Multiple
Entry
Points
Considered
as
One
Plant
Multiple
ground
water
wells
drawing
from
one
aquifer
and
delivering
disinfected
water
directly
to
the
distribution
system
may
be
considered
a
single
plant
with
approval
from
the
State.
Locations
prior
to
the
first
group
of
customers
of
any
well
are
an
acceptable
near­
entry
point
SMP
site.
Similarly,
for
multiple
consecutive
entry
points
considered
as
a
single
plant,
any
entry
point
would
be
acceptable
for
a
near­
entry
point
SMP
site.
(
See
Example
8.5.)

8.2.2
Average
Residence
Time
SMP
Sites
Sites
with
average
residence
time
should
represent
the
average
water
age
that
is
delivered
to
the
majority
of
customers
in
the
distribution
system.
In
most
distribution
systems,
average
residence
time
is
not
simply
one­
half
the
maximum
residence
time.
Ideally,
it
should
be
a
flow­
weighted
or
population­
weighted
average
residence
time.
EPA
recognizes
that
determining
this
value
is
very
complex
and,
at
best,
most
systems
can
only
make
a
rough
estimate.
Section
8.4
provides
methodologies
for
estimating
average
residence
time
with
various
types
of
data
and
tools.

8.2.3
High
TTHM
and
High
HAA5
Sites
It
is
not
the
intent
of
the
SMP
to
identify
peak
daily
or
hourly
DBP
concentrations.
Instead,
high
TTHM
and
high
HAA5
sites
should
be
chosen
to
represent
areas
in
the
distribution
system
with
the
highest
annual
average
DBP
concentrations.
Higher
temperatures
and
increased
residence
time
typically
lead
to
higher
TTHM
and
HAA5
concentrations.
However,
HAA5
can
biodegrade
when
disinfectant
residual
levels
are
low
or
non­
existent
and,
therefore,
a
high
HAA5
site
may
not
be
the
site
with
the
longest
residence
time.
These
principles
are
the
basis
of
the
guidance
provided
for
selecting
high
TTHM
and
high
HAA5
SMP
sites.
Table
8.3
summarizes
the
typical
characteristics
of
distribution
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
9
system
areas
with
high
TTHM
and
high
HAA5
levels.
Section
8.4
further
describes
how
data
sources
and
analysis
tools
can
be
used
to
identify
these
areas
in
the
distribution
system.

Table
8.3
Summary
of
Characteristics
of
High
TTHM
and
High
HAA5
Areas
Area
Characteristics
High
TTHM
S
Long
residence
time
(
e.
g.
remote
areas
with
few
customers
or
low
water
demand)
S
Low
or
no
disinfectant
residual,
also
high
heterotrophic
plant
count
(
HPC)
or
history
of
positive
coliform
S
Downstream
of
storage
facilities
S
Areas
with
historical
data
showing
high
TTHM
High
HAA5
S
Residence
time
can
vary
S
Low
but
existing
disinfectant
residual
(
to
prevent
biodegradation)
S
May
be
downstream
of
storage
facilities
S
Areas
with
historical
data
showing
high
HAA5
Note:
These
are
only
general
characteristics;
DBP
formation
in
distribution
systems
is
system­
specific.

8.3
Considerations
for
Systems
with
More
than
One
Plant
or
Entry
Point
This
section
describes
how
systems
with
multiple
plants
or
entry
points
should
distribute
the
sites
with
respect
to
the
influence
zone
of
each
plant
or
entry
point.

8.3.1
100
Percent
Purchasing
Systems
with
More
Than
One
Consecutive
System
Entry
Point
The
100
percent
purchasing
systems
are
not
required
to
assign
SMP
sample
sites
to
the
influence
zone
of
a
particular
entry
point.
When
selecting
average
residence
time
and
high
TTHM/
high
HAA5
SMP
sites,
100
percent
purchasing
systems
should
consider
the
quantity
and
quality
of
water
received
at
each
consecutive
system
entry
point.
For
example,
if
one
entry
point
supplies
75
percent
of
the
water
then
more
SMP
sites
should
be
located
in
the
influence
zone
of
that
supply.
Geographic
distribution
of
SMP
locations
should
also
be
considered.
Examples
8.6
and
8.7
illustrate
how
sites
could
be
distributed
with
respect
to
multiple
entry
points.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
10
LEGEND
SMP
Sample
Site
Storage
Tank
Oakville
WTP
Entry
Point
(
25%)
Mapleton
WTP
Influence
Zone
Oakville
WTP
Influence
Zone
Mapleton
WTP
Entry
Point
(
75%)

E
 
Entry
Point
A
 
Average
T
 
High
TTHMs
H
 
High
HAA5
E
E
A
A
A
H
H
H
T
T
T
T
Example
8.6
Large
and
Small
Surface
Water
Entry
Points
Your
City
is
a
100
percent
purchasing
system
serving
30,000
people
and
purchases
chlorinated
water
from
two
surface
water
wholesalers
(
Mapleton
and
Oakville).
Your
City
is
required
to
identify
12
SMP
sites
(
from
Table
8.1
 
2
near­
entry
points,
3
average,
4
high
TTHM,
and
3
high
HAA5
sites).
On
average,
Mapleton
supplies
Your
City
with
75
percent
of
its
water;
while
Oakville
provides
only
25
percent.
The
water
quality
from
each
is
similar.

Site
selection
rationale:

Based
on
the
average
flow
split
and
similar
water
quality,
approximately
75
percent
(
9)
of
the
sites
should
be
in
the
influence
zone
of
the
Mapleton
supply
and
the
remaining
25
percent
(
3)
should
be
in
the
influence
zone
of
the
Oakville
source.
As
shown
in
the
schematic,
in
order
to
achieve
a
good
geographic
coverage
of
the
distribution
system,
2
of
the
Mapleton
sites
are
located
in
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
11
Deep
Rock
Well
Entry
Point
(
60%)
Lory
RiverWTP
Influence
Zone
Deep
Rock
Well
Influence
Zone
Lory
River
WTP
Entry
Point
(
40%)

LEGEND
SMP
Sample
Site
Storage
Tank
E
 
Entry
Point
A
 
Average
T
 
High
TTHMs
H
 
High
HAA5
E
E
A
A
A
H
H
H
T
T
T
T
Example
8.7
Surface
Water
and
Ground
Water
Entry
Points
Your
City
is
a
100
percent
purchasing
system
serving
48,000
people
with
purchased
water
from
two
water
wholesalers.
The
Lory
River
WTP
supplies
40
percent
of
the
demand
with
surface
water.
The
Deep
Rock
well
supplies
60
percent
of
the
demand
with
ground
water.
Your
City
is
required
to
identify
12
SMP
sites
as
follows:
2
near­
entry
point,
3
average
residence
time,
4
high
TTHM,
and
3
high
HAA5.

SMP
selection
rational:

More
sites
are
placed
within
the
influence
area
of
the
Lory
River
WTP
because
it
is
a
surface
water
source
and
thus,
more
likely
to
have
higher
DBP
levels.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
12
8.3.2
Producing
Systems
with
More
than
One
Plant
As
indicated
in
Table
8.2,
the
rule
specifies
the
number
of
SMP
sites
for
each
plant.
For
most
systems,
the
distribution
areas
of
the
plants
are
not
distinctly
separate.
However,
systems
can
usually
identify
the
primary
influence
zones
of
each
plant
and
should
use
these
zones
to
assign
SMP
sites.
Recognizing
that
the
boundaries
of
influence
zones
can
overlap
and
change
on
a
daily,
hourly,
and
seasonal
basis,
SMP
sites
should
be
chosen
within
the
typical
(
during
normal
operating
mode)
influence
zone
boundaries,
as
best
can
be
determined.

Once
sample
sites
have
been
selected
based
on
the
typical
influence
zone
boundaries,
the
samples
must
be
collected
as
scheduled,
regardless
of
the
actual
source
of
water
serving
the
site
at
the
time
of
sampling
(
40
CFR
141.602(
c)).
If
it
is
suspected
or
known
that
the
source
of
water
supplying
a
particular
SMP
site
is
different
during
sample
collection,
then
this
should
be
noted
and
taken
into
consideration
when
evaluating
the
results
of
the
SMP.
However,
identification
of
the
source
of
supply
to
each
sample
site
during
each
sampling
event
is
not
required.

Where
overlap
exists
between
two
or
more
influence
zones,
the
water
quality,
quantity,
and
operating
characteristics
should
be
considered
when
locating
SMP
sites.
There
are
numerous
scenarios
that
could
exist
when
a
distribution
system
is
supplied
with
water
from
more
than
one
plant.
The
following
sections
provide
general
guidance
and
examples
for
four
specific
scenarios:

°
One
plant
produces
the
majority
of
the
water
(
Example
8.8)

°
One
plant
supplies
water
with
much
higher
TTHM/
HAA5
concentrations
than
the
other
plant(
s)
(
Example
8.9)

°
The
system
purchases
water
for
less
than
60
consecutive
days
per
year
(
Example
8.10)

°
The
system
has
a
seasonal
source
of
water
(
used
at
least
60
consecutive
days
per
year,
but
less
than
100
percent
of
the
time)
(
Example
8.11)

The
guidelines
for
these
four
scenarios
are
general
and
will
not
apply
to
all
systems
and
all
situations;
you
should
always
use
best
professional
judgement
when
selecting
SMP
sites.

One
Plant
Supplies
the
Majority
of
the
Water
In
systems
where
one
plant
delivers
substantially
more
water
than
another,
an
equal
distribution
of
sites
within
influence
zones
may
result
in
disproportionate
coverage
of
the
distribution
system.
That
is,
the
sites
representing
a
large
treatment
plant
must
cover
a
wider
geographic
area
than
the
sites
representing
a
smaller
plant.
Example
8.8
illustrates
this
situation
and
provides
an
SMP
selection
approach
that
maximizes
coverage
of
the
distribution
system
while
still
locating
SMP
sites
for
each
plant
in
the
appropriate
zone
of
influence.
In
the
example,
SMP
sites
required
for
the
smaller
plant
are
used
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
13
Red
SW
treatment
plant
Well
#
1
Well
#
2
Red
Plant
Influence
Zone
Legend
Red
plant
SMP
Site
Green
plant
SMP
site
¬
Well
Green
Plant
Influence
Zone
¬
¬
E­
Entry
Point
A
 
Average
T
 
High
TTHMs
H
 
High
HAA5
H
H
H
H
E
E
A
A
A
A
T
T
T
T
T
T
Example
8.8
Producing
System
with
One
Large
and
One
Small
Plant
A
system
supplying
12,000
people
has
2
chlorinated
plants,
Red
and
Green.
The
Red
plant
is
a
surface
water
treatment
plant
that
provides
8
MGD.
The
Green
plant
is
supplied
by
2
wells
drawing
from
the
same
aquifer,
produces
1
MGD,
and
has
been
approved
by
the
State
as
drawing
from
a
common
aquifer.
Generally,
the
Green
plant
supplies
the
east
area
of
the
distribution
system
and
the
Red
plant
supplies
all
other
areas.
From
Table
8.2,
a
total
of
8
SMP
sites
for
each
plant
are
required
for
mixed
surface
and
ground
water
systems.

Site
selection
rationale:

For
both
plants,
the
8
required
SMP
sites
are
located
in
the
influence
zone
of
the
respective
plant.
Because
the
Green
plant
has
a
much
smaller
influence
area,
Green's
sites
are
selected
to
cover
the
overlapping
mixing
zone,
thus
allowing
the
8
Red
sites
to
cover
the
larger
Red
influence
zone.
This
arrangement
of
sites
respects
the
requirement
to
locate
sites
within
individual
plant
influence
to
cover
the
entire
area
of
the
overlapping
influence
zones;
SMP
sites
for
the
large
plant
are
located
exclusively
in
the
influence
zone
of
the
large
plant.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
14
One
Plant
Supplies
Water
with
Much
Higher
DBP
Concentrations
Than
the
Others
Systems
should
also
consider
quality
of
water
when
locating
SMP
sites.
The
overall
objective
of
the
IDSE
SMP
is
to
identify
sites
in
the
distribution
system
where
water
with
representative
high
TTHM
and
HAA5
concentrations
is
delivered
to
customers.
If
you
suspect
that
the
high
TTHM
and/
or
high
HAA5
sites
will
be
in
the
influence
zone
of
a
particular
plant
on
more
than
a
seasonal
basis,
you
should
locate
SMP
sites
to
maximize
coverage
in
that
influence
zone.
Example
8.10
shows
how
SMP
sites
can
be
located
when
one
source
is
suspected
of
having
high
TTHM/
HAA5
concentrations.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
15
Riverdale
WTP
Influence
Zone
LEGEND
Riverdale
SMP
Sample
Sites
Spring
Hills
Sample
Site
Riverdale
WTP
(
60%)
Spring
Hills
WTP
Influence
Zone
Spring
Hills
WTP
(
40%)

E
 
Entry
Point
A
 
Average
T
 
High
TTHMs
H
 
High
HAA5
E
E
T
T
T
T
T
T
H
H
H
H
A
A
A
A
Example
8.9
Producing
System
with
One
High­
and
One
Low­
DBP
Plant
Your
City
is
a
producing
system
serving
85,000
people.
Your
City
operates
2
plants
 
Riverdale
(
a
surface
water
plant
with
moderate
to
high
source
water
TOC
levels)
and
Spring
Hills
(
a
low­
TOC
ground
water
plant).
Riverdale
provides
approximately
60
percent
of
your
daily
demand
and
Spring
Hills
the
remaining
40
percent.
Both
plants
use
free
chlorine
for
primary
and
secondary
disinfection.

From
Table
8.2,
Your
City
is
required
to
select
8
SMP
sample
locations
for
each
treatment
plant
(
a
total
of
16
sites).
Since
the
Spring
Hills
supply
is
likely
to
have
lower
DBP
concentrations
than
the
Riverdale
supply,
locate
the
Riverdale
SMP
sites
exclusively
in
the
Riverdale
influence
zone
and
use
the
Spring
Hills
SMP
sites
to
cover
the
mixing
zone.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
16
Emergency
Connections
(
Used
Less
Than
60
Consecutive
Days
per
Year)

Consecutive
entry
points
used
on
a
temporary
basis
that
provide
water
for
less
than
60
consecutive
days
per
year
are
not
considered
to
be
"
plants"
under
the
IDSE
SMP
requirements
(
141.602
(
d)(
2)).
In
other
words,
systems
do
not
have
to
identify
near­
entry
point,
average
residence
time,
or
high
TTHM/
HAA5
SMP
sites
for
these
entry
points.
However,
typical
water
demand
patterns
in
the
area
of
the
distribution
system
supplied
by
the
temporary
source
(
influence
zone)
should
be
considered
when
locating
SMP
sites
(
see
Example
8.10).

Example
8.10
Producing
Systems
with
Temporary
Sources
°
A
large
surface
water
system
buys
water
during
the
highest
temperature
month(
s)
from
a
system
with
a
low­
TOC
ground
water
source.
In
this
case,
SMP
sites
should
not
be
located
in
the
influence
zone
of
the
temporary
source;
focus
should
be
on
other
areas
of
the
distribution
system.
The
reason
for
this
is
the
influence
zone
of
the
temporary
source
is
likely
to
have
lower
DBP
concentrations
than
areas
served
by
the
surface
water
supply.

°
A
large
surface
water
system
buys
water
that
is
low­
TOC
ground
water
source,
but
not
during
the
highest
temperature
month(
s).
In
this
case,
you
should
consider
locating
SMP
sites
in
the
influence
zone
of
your
temporary
source
because
the
zone
will
be
more
representative
of
your
surface
water
source
during
the
highest
temperature
month.
This
is
particularly
applicable
if
you
believe
the
area
has
high
TTHM
or
high
HAA5
levels
when
it
is
supplied
by
your
normal
surface
water
supply.
You
should
be
cognizant,
however,
of
which
source
is
providing
the
water
that
you
are
collecting
during
your
SMP.
If
you
collect
a
sample
that
is
not
representative
of
your
surface
water
source,
you
should
note
this
information
in
your
IDSE
report
and
consider
that
when
selecting
final
Stage
2B
DBPR
compliance
monitoring
sites
(
see
sections
8.6
and
8.7
for
guidelines
for
selecting
Stage
2B
DBPR
compliance
monitoring
sites
and
completing
your
IDSE
report).
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
17
Purchasing
Water
on
a
Part­
time
Basis
(
Used
at
Least
60
Consecutive
Days
per
Year)

If
a
system
buys
water
from
a
wholesale
system
on
a
part­
time
or
seasonal
basis,
for
more
than
60
consecutive
days
of
the
year,
the
source
is
considered
to
be
a
"
plant"
under
the
IDSE
SMP
requirements
(
141.602
(
d)(
2)).
As
with
plants
operating
year­
round,
the
SMP
sites
for
a
seasonal
plant
should
be
located
in
the
influence
zone
of
that
plant.
Although
the
seasonal
plant
would
not
be
providing
water
to
the
SMP
sites
all
the
time,
the
SMP
sampling
sites
should
not
be
modified
once
sampling
has
begun
(
SMP
sites
should
remain
fixed
for
the
1­
year
monitoring
period).

Even
if
water
from
a
seasonal
plant
is
known
to
have
low
DBP
concentrations
relative
to
water
provided
by
other
plants
(
e.
g.,
a
seasonal
ground
water
supply
in
a
surface
water
system),
the
eight
sites
for
the
seasonal
plant
should
still
be
selected
within
the
influence
zone
of
that
plant.
DBP
data
of
all
plants
are
important
in
evaluating
the
entire
distribution
system.

Example
8.11
illustrates
the
SMP
site
selection
for
a
large
producing
system
that
operates
two
surface
water
plants
and
purchases
water
during
the
summer
to
meet
increased
seasonal
demands.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
18
Purchased
Water
Influence
Zone
Elm
Plant
Influence
Zone
Maple
Plant
Influence
Zone
Legend
Maple
plant
SMP
Site
Purchased
water
entry
point
SMP
site
Elm
plant
SMP
site
Maple
SW
treatment
plant
Elm
SW
treatment
plant
Entry
point
for
purchased
water
E
 
Entry
Point
A
 
Average
T
 
High
TTHMs
H
 
High
HAA5
E
E
E
H
H
H
H
H
T
T
T
T
T
T
T
T
T
H
A
A
A
A
A
A
Example
8.11
Producing
System
with
Seasonal
Plants
A
system
serving
chlorinated
water
to
55,000
people
has
three
plants:
Maple
plant
(
6
MGD
surface
water),
Elm
plant
(
3
MGD
surface
water),
and
purchased
water
from
a
neighboring
city
(
2
MGD
in
summer
only
 
for
more
than
60
consecutive
days).

Site
selection
rationale:

The
Maple
plant
and
Elm
plant
influence
zones
mostly
overlap;
together,
their
sites
cover
the
entire
area
except
the
influence
zone
of
the
purchased
water.
Although
the
system
only
purchases
during
the
summer,
those
sites
will
be
sampled
during
the
entire
1­
year
SMP
sampling
period
and
will
represent
the
surface
water
plants'
water
quality
for
a
majority
of
the
year.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
19
Tracer
Studies
System
Operating
Data
Hydraulic
Model
Maps
Geographic
Information
System
(
GIS)
SDS
Tests
Water
Quality
Data
8.4
Data
Sources
and
Tools
for
Identifying
Preliminary
SMP
Sites
Several
sources
of
information
can
be
used
to
help
select
SMP
sites
that
represent
average
residence
time,
high
TTHM,
and
high
HAA5
concentrations
(
see
Figure
8.1
below).

Figure
8.1
Data
Sources
and
Tools
for
Selecting
SMP
Sites
These
data
sources
and
tools
are
best
applied
in
combination
with
each
other.
For
example,
a
map
is
critical
in
assessing
geographic
and
population
coverage;
however,
it
is
of
limited
use
when
used
alone
to
identify
average
residence
time
or
high
HAA5
sites.

Generally,
data
used
to
identify
SMP
sites
should
be
less
than
10
years
old
and
represent
the
current
distribution
system
and
treatment
plant(
s)
configuration.
Chapter
3
discusses
the
quality
of
data
recommended
for
use
in
a
historical
data­
based
SSS.

This
section
describes
how
each
data
source
can
be
used
to
identify
preliminary
SMP
sites
representing
high
TTHM,
high
HAA5,
and
average
residence
time.
Section
8.5
presents
step­
by­
step
methodologies
for
using
combinations
of
these
data
sources
to
select
final
SMP
sites.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
20
8.4.1
Maps
Map
features
that
may
be
helpful
in
selecting
SMP
sites
include:

°
Length
and
diameter
of
pipes
°
Age
of
pipes
°
Pressure
zone
delineations
with
valving
identified
°
Location
of
distribution
system
pumping
stations
°
Location
and
configuration
of
storage
facilities
°
Location
of
fire
hydrants
and
flush
valves
°
Existing
land
use
°
Population
density
°
Location
of
booster
disinfection
stations
°
Entry
points
with
source
type
noted
°
System
boundary
lines
8.4.1.1
High
TTHM
and
High
HAA5
Sites
Generally,
areas
with
light
development,
with
low
residential
population
density,
or
between
pressure
zones
that
are
furthest
away
from
the
treatment
plant(
s)
are
likely
to
have
the
longest
residence
times.
Therefore,
these
areas
have
potentially
high
TTHM
concentrations
and,
provided
there
is
a
detectable
disinfectant
residual,
high
HAA5
concentrations.

In
general,
sites
at
the
very
end
of
a
distribution
system
main
with
no
customers
should
not
be
selected:

°
In
many
distribution
systems,
there
may
be
no
customers
at
the
actual
physical
end
of
some
dead­
end
sections
of
a
water
main.
Water
quality
at
this
type
of
location
is
not
truly
"
representative"
of
water
in
the
distribution
system
that
is
delivered
to
customers.

High
TTHM
(
and
in
some
cases
HAA5)
SMP
sites
should
be
generally
located
near
the
ends
of
the
distribution
system
at
or
before
the
last
group
of
customers
or
in
mixing
zones.

Sample
sites
should
be
located
prior
to
the
last
fire
hydrant.

Sample
sites
should
not
be
located
at
a
dead­
end
where
there
are
no
customers.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
21
°
High
TTHM
and,
in
some
cases,
high
HAA5
SMP
sites
should
generally
be
chosen
near
the
end
of
the
distribution
system
at
the
last
group
of
customers
or
in
mixing
zones
where
"
hydraulic
dead­
ends"
might
occur.
Samples
should
always
be
collected
at
locations
prior
to
(
upstream
of)
the
last
fire
hydrant.

Storage
facilities
in
a
distribution
system
increase
water
age.
During
tank
drain
cycles,
water
age
immediately
downstream
of
a
storage
facility
may
be
significantly
(
e.
g.,
several
days
or
more)
older
than
"
fresh"
water
upstream
of
the
storage
facility.
As
a
result,
areas
of
a
distribution
system
receiving
water
that
has
been
stored
may
have
higher
TTHM
and
HAA5
concentrations
than
areas
that
do
not
receive
any
stored
water.
Therefore,
you
should
generally
locate
your
high
TTHM
sites
and,
in
some
cases,
high
HAA5
sites
downstream
of
storage
facilities.

8.4.1.2
Average
Residence
Time
Sites
Average
residence
time
is
the
average
age
of
water
delivered
to
the
majority
of
customers
in
a
distribution
system.
Estimating
average
distribution
system
residence
time
based
solely
on
maps
can
be
difficult
and
requires
a
thorough
understanding
of
your
distribution
system.
Under
ideal
circumstances,
maps
are
just
one
tool
that
can
be
combined
with
other
data
and
tools
(
e.
g.,
disinfectant
residual
data,
hydraulic
modeling)
to
identify
areas
that
are
representative
of
average
water
age.
These
other
data
and
tools
are
discussed
further
in
sections
8.4.2
through
8.4.7.

Approximate
average
residence
time
areas
can
be
identified
by
looking
for
service
areas
with
the
most
development.
If
a
few
large
customers
exist
in
a
system,
then
their
location
should
be
identified
and
the
effect
of
water
flowing
to
them
taken
into
consideration.
In
many
systems
that
do
not
have
large
individual
customers,
highly
developed
areas
in
the
approximate
geographic
center
of
the
distribution
system
are
potential
average
residence
time
sites.

8.4.2
Distribution
System
Water
Quality
Data
Systems
routinely
sample
for
various
water
quality
parameters
as
required
by
regulations
or
for
operational
purposes.
A
review
of
recent
historical
DBP
and/
or
disinfectant
residual
data
(
free
chlorine
or
chloramine)
can
be
very
useful
in
the
selection
of
SMP
sample
sites.

8.4.2.1
Disinfectant
Residual
Data
Because
chlorine
and
chloramines
decay
over
time,
low
disinfectant
residuals
relative
to
those
leaving
the
treatment
facility
(
or
entering
through
a
consecutive
system
entry
point)
can
generally
be
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
22
Sources
of
disinfectant
residual
data:
­
TCR
data
­
Stage
1
DBPR
data
(
for
some
systems)
­
Operational
sample
sites
­
Sampling
in
response
to
customer
complaints
considered
an
indicator
of
increased
water
age.
A
review
of
disinfectant
residual
data
from
existing
distribution
system
monitoring
sites
can
help
identify
the
areas
of
your
system
with
the
highest
residence
time
and
those
with
average
residence
time.
Sources
of
disinfectant
residual
data
may
include
regular
compliance
monitoring
sites
(
e.
g.,
Total
Coliform
Rule
(
TCR)
or
Stage
1
DBPR
monitoring
sites),
operational
sample
sites,
or
special
sites
sampled
in
response
to
customer
complaints.
Combining
the
data
from
these
various
sample
sites
may
help
you
better
understand
the
change
in
disinfectant
residual
as
water
flows
through
your
distribution
system
and,
consequently,
help
you
choose
the
required
SMP
sample
sites.

There
are
cases,
however,
where
lower
disinfectant
residuals
do
not
necessarily
indicate
greater
water
age.
Common
factors
that
can
influence
disinfectant
residual
decay
and
affect
the
relationship
between
residual
levels
and
water
age
are:

°
Pipe
material
and
internal
lining
°
Corrosion
condition
in
the
pipe
°
Biofilm
growth
in
the
pipe
°
Accumulation
of
sediment
in
the
pipe
°
Booster
disinfection
In
particular,
use
of
disinfectant
residual
data
becomes
difficult
when
booster
disinfection
is
applied.
Booster
disinfection
is
the
practice
of
adding
a
disinfectant
in
the
distribution
system
to
raise
the
disinfectant
residual
concentration
and
is
commonly
used
in
peripheral
zones
of
the
distribution
system
or
near
storage
tanks
where
water
age
may
be
high
and
disinfectant
residuals
are
low.
TTHM
and
HAA5
levels
are
likely
to
increase
after
a
booster
disinfectant
is
applied.
Additional
TTHM
and
HAA5
may
be
formed
due
to
the
greater
concentration
of
disinfectant
available
for
reaction
with
DBPs
precursors.
Furthermore,
the
additional
disinfectant
prevents
the
biological
degradation
of
HAA5,
thus
favoring
their
accumulation
in
the
areas
of
the
distribution
system
affected
by
booster
chlorination.

If
your
system
does
not
have
much
disinfectant
residual
data,
or
if
you
are
not
able
to
identify
sites
with
average
or
high
residence
times
based
on
your
existing
data,
you
may
want
to
collect
additional
disinfectant
residual
data
from
your
system
to
better
characterize
your
system
and
provide
a
better
basis
for
selecting
SMP
sites.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
23
1)
High
TTHM
and
High
HAA5
Sites
Booster
Disinfection
If
your
system
uses
booster
disinfection
continuously
or
intermittently,
the
high
TTHM
and
HAA5
sites
should
not
be
located
before
a
booster
disinfection
station.

Low
Disinfectant
Residual
Relative
to
System
Average
Low
disinfectant
residuals
relative
to
the
system
average
generally
indicate
longer
residence
times,
and
may
correlate
with
higher
TTHM
and
HAA5
concentrations.
Very
low
or
no
disinfectant
residual,
however,
could
also
indicate
biological
decay
of
HAA5,
and
should
generally
not
be
chosen
as
your
high
HAA5
site.

°
When
selecting
preliminary
high
HAA5
sites,
locations
with
free
chlorine
residuals
less
than
0.2
mg/
L
or
chloramine
residuals
less
than
0.5
mg/
L
should
not
be
selected
because
of
the
potential
for
biodegradation
of
HAA5.

°
High
HAA5
sites
should
have
no
significant
increase
in
recorded
HPCs
to
ensure
a
low
potential
for
HAA5
biodegradation.
If
you
have
HPC
data,
a
comparison
of
disinfectant
residual
and
HPC
data
can
help
you
more
precisely
determine
the
threshold
disinfectant
residual
below
which
HPC
levels
begin
to
increase.
However,
HPC
testing
is
not
required
as
a
part
of
the
IDSE.

Review
Disinfectant
Residual
Data
from
the
Warmer
Months
Because
disinfectant
residuals
typically
decay
faster
during
the
summer,
a
review
of
data
from
the
summer
months
may
be
more
useful
in
identifying
areas
with
consistently
low
residuals.
During
the
winter,
disinfectants
are
usually
more
persistent,
and
residuals
can
often
be
maintained
in
relatively
old
water
within
a
distribution
system.
The
correlation
between
residence
time
and
residual
decay
is
less
pronounced
in
the
colder
months.

2)
Average
Residence
Time
Sites
One
of
the
best
ways
to
calculate
average
residence
time
is
by
using
a
hydraulic
model
(
see
Chapter
3
for
information
on
hydraulic
modeling).
However,
if
this
tool
is
not
available,
calculating
the
average
disinfectant
residual
in
your
distribution
system
can
help
you
identify
locations
with
average
water
residence
time
(
this
method
is
not
valid
for
areas
in
the
influence
of
booster
disinfection).
When
calculating
average
disinfectant
residual,
it
is
important
that
you
use
data
from
sites
that
are
representative
of
your
entire
distribution
system.
One
way
to
do
this
is
to
limit
data
to
those
collected
at
your
TCR
monitoring
sites
(
the
TCR
requires
that
all
monitoring
sites
combined
represent
the
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
24
distribution
system).
Use
of
historical
data
or
other
data
(
e.
g.,
data
from
customer
complaints)
could
skew
the
results
if
a
large
portion
of
the
data
are
from
a
single
area.

Assuming
your
disinfectant
residual
data
are
representative
of
your
distribution
system,
the
following
analysis
of
TCR
monitoring
data
can
be
used
to
help
identify
sites
with
average
residence
time:

1)
Calculate
an
average
disinfectant
residual
at
each
of
your
TCR
sites
using
data
from
your
warmest
months
(
chlorine
decay
is
more
pronounced
in
warmer
temperatures
so
you
are
more
likely
to
see
larger
changes
in
chlorine
residual
from
one
point
to
the
next).

2)
Using
averages
from
the
individual
sites,
calculate
an
overall
distribution
system
average
residual
concentration.

3)
Those
sites
with
an
average
residual
close
to
the
distribution
system
average
can
be
considered
representative
of
average
residence
time
in
the
distribution
system.

Note,
if
your
system
has
booster
disinfection,
then
residual
data
collected
after
those
locations
will
skew
this
analysis.
You
should
either
omit
that
data
or
estimate
what
the
residual
would
be
without
the
added
disinfectant.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
25
Monthly
Average
(
mg/
L)
Jun
Jul
Aug
#
1
1.4
1.3
1.6
1.4
#
2
0.7
0.9
0.7
0.8
#
3
1.0
0.9
1.2
1.0
#
4
0.6
0.6
0.7
0.6
#
5
0.9
1.2
1.4
1.2
#
6
0.4
0.5
0.4
0.4
#
7
0.2
0.3
0.6
0.4
#
8
1.5
1.7
1.7
1.6
#
9
0.9
0.7
0.8
0.8
#
10
0.5
0.3
0.8
0.5
Distribution
System
Ave
0.8
0.8
1.0
0.9
Site
Average
(
mg/
L)
Site
ID
Example
8.12
System
Average
Disinfectant
Residual
Calculation
A
system
with
June,
July,
and
August
as
their
warmest
months
has
the
residual
data
below.
The
averages
for
the
system
and
each
site
are
calculated
as
shown.
Note
that
sites
#
2,
#
3,
and
#
9
have
average
chlorine
residual
concentrations
close
to
the
system
average.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
26
8.4.2.2
DBP
Data
Non­
compliance
DBP
(
TTHM
and
HAA5)
data,
collected
in
addition
to
your
Stage
1
DBPR
compliance
monitoring
data,
can
be
useful
in
selecting
high
TTHM
and
high
HAA5
SMP
sites.
Remember,
however,
that
Stage
1
DBPR
compliance
monitoring
sites
cannot
be
used
as
SMP
sites
(
141.602(
b)).
For
surface
water
systems,
historical
DBP
data
should
be
evaluated
with
respect
to
raw
water
quality
conditions
before
and
during
the
sampling
period
(
e.
g.,
changes
in
TOC
concentration
from
year
to
year
can
significantly
affect
DBP
levels).
DBP
data
should
not
be
used
for
the
purpose
of
estimating
average
residence
time
because
DBP
formation
is
complex
and
dependent
on
many
factors.
(
See
Appendix
B
for
a
discussion
of
DBP
formation.)

If
your
system
has
extensive
non­
compliance
TTHM
and
HAA5
data
at
a
variety
of
sites
throughout
your
distribution
system,
you
may
wish
to
consider
completing
an
SSS
based
on
your
historical
data,
possibly
with
a
limited
amount
of
new
monitoring.
See
Chapter
3
if
you
think
you
may
be
able
to
use
historical
data
alone
or
in
combination
with
other
data
for
an
SSS.

High
TTHM
and
High
HAA5
Sites
Regulatory
compliance
data
(
including
all
data
collected
under
the
Stage
1
DBPR)
are
not
a
definitive
source
for
identifying
the
representative
high
TTHM
and
HAA5
concentrations.
There
may
now
be
other
areas
with
higher
TTHM
and
HAA5
concentrations
that
have
not
been
sampled
or
do
not
have
high
historical
results
due
to
differences
in
flow
or
water
quality
at
the
time
of
sampling.
Therefore,
historical
data
should
always
be
used
in
conjunction
with
other
data
sources
and
tools.
Results
from
a
Simulated
Distribution
System
(
SDS)
test
can
also
be
helpful
in
evaluating
TTHM
and
HAA5
data.
(
Section
8.4.3
describes
the
SDS
test
and
how
it
can
be
used
in
conjunction
with
DBP
data
to
select
SMP
sites
and
Appendix
D
describes
the
recommended
procedure
for
conducting
the
SDS
test.)

Good
candidates
for
high
TTHM
and
HAA5
sites
include:

°
Historic
sample
sites
with
high
TTHM
concentrations
in
areas
with
long
residence
times.

°
Historic
sample
sites
with
high
HAA5
concentrations
in
areas
that
consistently
maintain
a
disinfectant
residual.

°
Historic
sample
sites
with
TTHM/
HAA5
concentrations
that
are
close
to
the
TTHM/
HAA5
concentration
from
an
SDS
test
for
maximum
residence
time.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
27
8.4.3
Simulated
Distribution
System
Laboratory
Test
An
SDS
laboratory
test
is
another
tool
that
can
be
used
in
conjunction
with
Stage
1
DBPR
compliance
monitoring
or
other
DBP
data
to
select
SMP
sites.
In
the
SDS
test,
finished
water
samples
are
collected
(
generally
at
system
entry
points)
and
stored
for
selected
periods
of
time
at
chemical
and
environmental
conditions
simulating
those
occurring
in
the
distribution
system
(
e.
g.,
temperature
and
pH).
These
samples
are
analyzed
for
TTHM
and
HAA5
concentrations
at
the
end
of
the
selected
holding
time.
Appendix
D
describes
the
recommended
procedures
for
conducting
an
SDS
test.
Note
that
this
procedure
would
have
to
be
modified
if
a
system
has
a
booster
disinfection
station.

One
use
of
an
SDS
test
is
to
confirm
that
existing
Stage
1
DBPR
or
other
DBP
monitoring
sites
represent
the
maximum
water
residence
time.
For
this
purpose,
SDS
samples
should
be
collected
in
conjunction
with
(
preferably
on
the
same
day
or
1
to
3
days
before)
the
DBP
samples
collected
from
the
distribution
system.
At
least
one
SDS
sample
should
be
stored
for
a
period
of
time
approximately
equal
to
the
maximum
residence
time,
then
analyzed
for
TTHM
and
HAA5
concentrations.
(
Note:
an
SDS
sample
must
have
a
detectable
disinfectant
residual
at
the
end
of
the
holding
time.)
It
would
also
be
useful
in
evaluating
results
to
hold
an
SDS
sample
for
a
period
of
time
equal
to
your
average
system
residence
time.
If
your
maximum
residence
time
is
more
than
5
days,
a
third
SDS
test,
at
a
residence
time
between
the
average
and
maximum
residence
time,
is
recommended.
All
SDS
samples
should
be
stored
at
the
same
temperature
as
the
distribution
system
water
(
see
Appendix
D
for
suggested
procedures).

If
distribution
system
TTHM
of
HAA5
results
are
equivalent
to
or
higher
than
the
SDS
maximum
residence
time
TTHM
or
HAA5
results,
you
can
infer
that
the
site
is
likely
representative
of
high
TTHM
or
HAA5
levels.
Remember
that
you
cannot
use
Stage
1
DBPR
sites
for
the
SMP;
however,
you
may
wish
to
investigate
other
locations
with
similar
hydraulic
and
disinfectant
residual
characteristics
for
your
high
TTHM
SMP
sites
(
and
high
HAA5
sites
if
they
meet
other
criteria).
Examples
8.13
and
8.14
demonstrate
how
SDS
test
results
and
data
from
Stage
1
DBPR
and
operational
monitoring
sites
can
be
used
to
select
SMP
sites.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
28
Example
8.13
Using
the
SDS
Test
to
Evaluate
Operational
Monitoring
Locations
(
Big
City
Water)

Big
City
Water
has
collected
the
following
distribution
system
data
and
SDS
test
results.

Sample
Location/
Type
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

SDS
at
Maximum
Residence
Time1
78
46
Stage
1DBPR
Max
Residence
Time
#
1
75
45
Stage
1DBPR
Max
Residence
Time
#
2
71
35
Operational
Location
#
1
79
43
Operational
Location
#
2
40
50
Operational
Location
#
3
80
45
Operational
Location
#
4
61
50
Note:
In
this
example,
the
SDS
sample
was
collected
on
a
Monday;
distribution
system
samples
were
collected
during
that
week.
1
Maximum
residence
time
determined
using
the
results
of
a
previously
conducted
tracer
study.

Based
upon
the
SDS
results
for
Big
City
presented
above,
the
following
conclusions
can
be
drawn:

°
Stage
1
DBPR
max
residence
time
#
1
most
likely
represents
high
TTHM
and
HAA5
concentrations.

°
Stage
1
DBPR
max
residence
time
#
2
may
represent
high
TTHM,
but
not
HAA5
(
possible
biodegradation).

°
Operational
locations
#
1
and
#
3
most
likely
represent
high
TTHM
and
HAA5
concentrations.

°
Operational
locations
#
2
and
#
4
represent
only
high
HAA5
concentrations.

For
this
example,
high
TTHM
SMP
sites
should
be
located
in
areas
with
similar
characteristics
to
Stage
1
DBPR
max
residence
time
#
1
and
#
2,
or
operational
locations
#
1
and
#
3.
High
HAA5
sites
should
be
located
in
areas
with
similar
characteristics
to
operational
locations
#
2
and
#
4
(
as
long
as
there
is
a
disinfectant
residual
concentration).
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
29
Example
8.14
Using
the
SDS
Test
to
Evaluate
Operational
Monitoring
Locations
(
Blue
Ridge
Water)

Blue
Ridge
Water
has
the
following
SDS
and
distribution
system
data.

Sample
Location/
Type
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

SDS
at
Maximum
Residence
Time1
100
67
Stage
1DBPR
Max
Residence
Time
#
1
98
55
Stage
1DBPR
Max
Residence
Time
#
2
72
58
Operational
Location
#
1
65
45
Operational
Location
#
2
95
62
Operational
Location
#
3
91
72
Operational
Location
#
4
80
62
Note:
In
this
example,
the
SDS
sample
was
collected
on
a
Monday;
distribution
system
samples
were
collected
during
that
week.
1
Maximum
residence
time
calculated
using
an
hydraulic
model.

Based
upon
the
SDS
results
for
Blue
Ridge
presented
above,
the
following
conclusions
can
be
drawn:

°
Stage
1
DBPR
max
residence
time
#
2
may
not
be
representative
of
high
TTHM
concentrations.

°
Operational
locations
#
2
and
#
3
most
likely
represent
high
TTHM
and
HAA5
concentrations.

°
Operational
location
#
4
represents
only
high
HAA5
concentrations.

For
this
example,
high
TTHM
SMP
sites
should
be
located
in
areas
with
similar
characteristics
to
Stage
1
DBPR
max
residence
time
#
1
or
operational
locations
#
2
and
#
3.
High
HAA5
sites
should
be
located
in
areas
with
characteristics
similar
to
operational
location
#
4
(
as
long
as
there
is
a
disinfectant
residual
concentration
and
no
evidence
of
bacteriological
activity).
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
30
SDS
results
must
viewed
with
caution.
Distribution
system
conditions
are
complex
and
cannot
be
perfectly
replicated
in
the
laboratory,
so
some
error
is
expected.
Also,
if
you
do
not
have
a
good
idea
as
to
your
true
maximum
distribution
system
residence
time,
your
SDS
results
may
indicate
your
Stage
1
DBPR
sites
are
inadequate
when,
in
fact,
they
are
representative
of
maximum
residence
time.
Similarly,
if
the
SDS
test
conditions
are
not
representative
to
the
treatment
(
i.
e.,
source
and
finished
water
quality)
and
distribution
system
conditions,
the
test
results
can
be
misinterpreted.
If
your
system
uses
booster
chlorination,
the
SDS
test
should
be
run
for
a
finished
water
sample
and
a
sample
taken
after
the
addition
of
the
booster
disinfectant
dose.

Another
use
of
an
SDS
test
is
to
help
describe
DBP
formation
in
the
distribution
system
and,
in
conjunction
with
Stage
1
DBPR
compliance
monitoring
and
other
data,
determine
average
and
maximum
residence
time.
Appendix
D
describes
how
SDS
tests
can
be
used
to
estimate
average
and
maximum
residence
time
using
DBP
and
chlorine
residual
data.

8.4.4
Models
A
water
distribution
system
model
is
a
computer
program
that
simulates
the
hydraulic
behavior
of
water
in
a
distribution
system.
Water
distribution
system
models
are
widely
used
in
the
water
industry
for
planning
and
operations.
Several
public
domain
and
commercial
software
modeling
packages
are
available.
For
instance,
EPA
developed
a
water
quality
modeling
software
package,
EPANET,
that
is
available
without
charge
via
the
internet.
Your
water
distribution
system
model
should
be
adequately
calibrated
when
selecting
SMP
sample
sites
(
see
Chapter
3
for
a
discussion
of
model
calibration).

A
water
distribution
system
hydraulic
model
can
predict
water
age
in
a
distribution
system
when
it
is
run
under
extended
period
simulation
conditions
(
i.
e.,
water
production,
demand,
etc.,
are
allowed
to
change
over
time).
In
addition,
most
models
can
track
the
movement
of
water
from
each
plant
or
supply
point
through
the
distribution
system.
Model
results
can
provide
a
picture
of
the
influence
zone
of
each
entry
point
and
identify
blending
zones.

The
size
of
your
system
and
the
degree
of
skeletonization
of
your
hydraulic
model
will
determine
how
useful
the
model
can
be
for
selecting
SMP
sites.
Skeletonization
refers
to
the
degree
of
detail
relating
to
distribution
system
piping
in
your
model.
Highly
skeletonized
models
may
only
show
large
distribution
mains
and
omit
much
of
the
smaller
piping
in
individual
subdivisions
or
other
areas
of
the
distribution
system.
In
such
cases,
highly
skeletonized
models
may
be
of
limited
use
in
large
systems
To
obtain
a
free
copy
of
EPANET
go
to:

http://
www.
epa.
gov/
ordntrnt/
ORD/
NRMRL/
wswrd/
epanet.
html
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
31
where
small
pipes
account
for
significant
localized
increases
in
system
residence
time.
Because
hydraulic
models
usually
are
somewhat
skeletonized
and
have
varying
degrees
of
calibration
and
accuracy
of
demand
allocation,
best
professional
judgement
should
always
be
used
when
analyzing
the
results
and
using
model
outputs
to
assist
in
the
selection
of
preliminary
sites.

It
is
highly
recommended
that
existing,
calibrated
water
distribution
and
water
quality
models
be
used
to
estimate
water
age,
identify
influence
zones,
and
identify
mixing
zones
to
help
select
SMP
sample
sites.
If
a
model
does
not
already
exist,
the
time
and
expense
to
create
a
new
model
and
train
staff
solely
for
use
in
selecting
IDSE
SMP
sample
sites
may
not
be
justified.
Model
development
or
enhancement
may
be
justified
if
you
intend
to
employ
the
model
for
other
uses
in
addition
to
the
selection
of
SMP
sample
sites.

If
you
have
an
existing,
detailed,
well
calibrated
distribution
system
model,
as
well
as
appropriately
trained
staff
to
operate
the
model
and
evaluate
results,
you
may
wish
to
consider
completing
an
SSS
based
on
the
use
of
your
model
and
a
limited
amount
of
new
testing.
Chapter
3
describes
the
requirements
for
an
SSS
using
a
water
distribution
system
model.

8.4.4.1
High
TTHM
Sites
Water
distribution
system
modeling
software
can
be
used
to
identify
high
residence
time
locations
(
most
often
your
high
TTHM
sites)
when
used
in
the
Extended
Period
Simulation
(
EPS)
mode.
When
the
run
time
of
an
EPS
model
is
long
enough
to
produce
a
consistent
pattern
of
water
age
values
at
all
nodes,
sometimes
with
repeating
fluctuations
due
to
diurnal
variations
in
water
demands,
then
the
water
age
values
at
the
model
nodes
can
be
used
for
the
purpose
of
identifying
high
residence
time
locations.

One
way
to
show
high
residence
time
locations
is
by
color
coding
each
model
node
according
to
its
residence
time.
High
TTHM
sites
should
be
chosen
from
the
area
or
areas
of
the
distribution
system
where
the
high
residence
time
model
nodes
are
located.
The
sample
sites
do
not
have
to
be
chosen
at
the
exact
location
of
a
model
node,
just
in
the
general
area
identified
by
the
model
results.

Precautions
in
using
model
data
to
select
high
TTHM/
HAA5
sites
include:

°
If
no
water
demand
is
applied
to
dead­
end
nodes
in
a
model
or
if
the
water
demand
in
a
dead­
end
is
highly
uncertain,
the
water
age
results
for
those
nodes
can
be
unrealistic
and
meaningless.

°
The
accuracy
of
water
age
estimates
from
a
model
generally
decreases
as
the
model
moves
from
large
diameter
mains
to
small
diameter
mains
to
subdivision
piping
and
dead­
ends.
This
is
due
to
the
increasing
uncertainty
in
water
usage
rates
as
one
moves
from
large,
aggregate
demands
to
smaller
demands
exerted
by
a
few
customers
or
a
single
customer.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
32
°
If
the
model
is
skeletonized,
the
model
results
for
high
residence
time
areas
should
be
compared
to
maps
of
the
actual
distribution
system
piping
and
to
actual
customer
locations
in
those
areas
before
sample
sites
are
finalized
in
order
to
assure
that
the
sample
site
is
representative
of
the
actual
distribution
system
and
not
just
the
skeletonized
model
in
the
high
residence
time
areas.

°
Residence
time
is
just
one
factor
for
identifying
high
TTHM
sites
and
should
be
compared
with
other
distribution
system
data
(
e.
g.,
disinfectant
residual
data)
before
making
your
preliminary
SMP
site
selections.

Because
water
distribution
system
models
usually
are
somewhat
skeletonized
and
have
varying
degrees
of
calibration
and
accuracy
of
demand
allocation,
best
professional
judgement
should
always
be
used
when
analyzing
the
results
and
using
model
outputs
to
assist
in
the
selection
of
preliminary
SMP
sample
sites.

Blending
Zones
In
some
cases,
there
may
be
zones
in
the
distribution
system
where
water
flowing
from
opposite
directions
meet.
This
can
occur
in:

°
Long,
looping
mains
°
The
interface
of
the
influence
zones
of
two
or
more
different
supply
points
°
Areas
where
different
pressure
zones
meet
within
one
system
This
type
of
area
is
sometimes
called
a
"
blending
zone"
and
may
act
as
a
hydraulic
dead­
end.
Blending
zones
can
occur
anywhere
in
the
distribution
system,
but
they
more
often
occur
in
the
central
portion
of
a
distribution
system.
If
the
water
demand
around
the
blending
zone
is
low,
then
the
water
age
and
TTHM
and
HAA5
concentrations
could
be
high.
Hydraulic
models
can
be
useful
in
locating
blending
zones
and
identifying
high
TTHM
or
HAA5
locations
within
the
blending
zone.

8.4.4.2
High
HAA5
Sites
The
criteria
and
procedure
for
selecting
preliminary
high
HAA5
SMP
sites
using
a
water
distribution
system
model
is
generally
the
same
as
that
described
for
selecting
high
TTHM
sites
with
one
important
difference:
the
locations
chosen
to
represent
high
HAA5
must
have
a
detectable
disinfectant
residual.
HAA5
concentrations
typically
increase
in
distribution
systems
as
water
age
increases
but
can
also
decrease
if
disinfectant
residuals
are
not
present
and
biological
activity
is
high.
High
HAA5
sites
should
be
chosen
from
locations
with
a
high
residence
time
and
a
detectable
disinfectant
residual.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
33
8.4.4.3
Average
Residence
Time
Sites
Average
residence
time
SMP
sites
can
be
selected
from
locations
with
residence
times
close
to
the
flow­
weighted
mean
of
all
nodal
residence
times
(
or
system
average).
As
with
selecting
high
TTHM/
HAA5
sites,
color
coding
nodes
by
nodal
residence
time
can
be
helpful.
SMP
sample
sites
should
be
chosen
from
the
area
or
areas
of
the
distribution
system
where
the
nodal
residence
time
is
close
to
the
system
average.
The
SMP
sample
sites
do
not
have
to
be
chosen
at
the
exact
location
of
a
model
node,
just
in
the
general
area
identified
by
the
model
results.

8.4.5
Tracer
Studies
Tracer
studies
can
be
used
to
determine
actual
water
residence
times
in
a
distribution
system
under
specific
conditions
and
are
sometimes
used
to
calibrate
water
distribution
system
models.
They
are
particularly
useful
for
predicting
water
residence
time
in
areas
of
a
system
where
there
is
uncertainty
about
true
pipe
diameters
due
to
poor
records
or
the
buildup
of
corrosion
deposits
affecting
system
hydraulics.
When
pipe
diameters
in
a
model
are
inaccurate,
model
predictions
can
be
very
different
from
the
actual
hydraulic
conditions
in
a
distribution
system.

You
can
perform
a
tracer
study
by
monitoring
the
concentration
of
a
conservative
constituent
(
i.
e.,
a
chemical
that
does
not
degrade
over
time)
through
the
distribution
system.
Chemicals
used
for
tracers
must
not
be
harmful
to
people
or
the
environment.
Tracer
chemicals
can
be
substances
that
are:

°
Specially
injected
or
normally
injected
in
the
water
for
treatment
purposes
(
e.
g.,
hydrofluorosilic
acid
or
sodium
fluoride)

°
Characteristic
of
the
finished
water
(
e.
g.,
hardness,
conductivity)

Before
injecting
any
tracer,
a
baseline
concentration
of
the
tracer
in
the
distribution
system
water
should
be
determined
(
fluoride,
the
most
common
tracer,
may
be
normally
present
in
trace
amounts).
If
your
system
adds
fluoride,
you
can
turn
off
the
fluoride
feed
for
a
period
of
time,
and
monitor
the
resulting
decrease
of
its
concentration
throughout
the
distribution
system.

If
you
do
not
routinely
add
fluoride
to
the
finished
water,
you
can
conduct
tracer
tests
by
injecting
a
small
dose
of
fluoride
(
about
1
mg/
L)
into
the
water
entering
the
distribution
system.
However,
flouride
can
interact
with
the
material
deposited
inside
pipes
and
storage
facilities,
reducing
the
accuracy
of
the
calculated
residence
times.
As
a
result,
you
must
inject
sufficient
fluoride
to
meet
the
"
fluoride
demand"
of
your
distribution
system
while
assuring
that
fluoride
concentrations
in
the
distribution
system
do
not
exceed
allowable
concentrations
of
4
mg/
L
(
the
primary
maximum
contaminant
limit
(
MCL)
for
fluoride
is
4
mg/
L
and
the
secondary
MCL
which
is
non­
enforceable
is
2
mg/
L).
If
other
tracers
are
used
such
as
calcium
chloride
or
sodium
chloride,
State
environmental
agencies
may
require
that
food
grade
chemicals
are
used
or
that
other
assurances
are
made
concerning
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
34
the
safety
of
the
tracer.
With
some
tracer
chemicals,
systems
may
want
to
consider
notifying
sensitive
users.

When
selecting
tracer
monitoring
locations,
you
should
consider
the
following:

°
Major
intersections
or
branches
in
large
transmission
mains
°
Branches
in
minor
mains
where
flow
is
split
between
two
or
more
groups
of
customers
°
Storage
tanks
°
Entry
points
to
large
commercial
or
industrial
users
°
Prior
to
the
last
fire
hydrant
in
remote
areas
with
few
customers
To
adequately
characterize
distribution
system
residence
time,
tracer
concentrations
should
be
measured
frequently
and
in
relatively
close
proximity
to
one
another.
The
frequency
of
sampling
will
determine
the
accuracy
of
the
study
results.
For
example,
if
sampling
is
conducted
every
8
hours
the
water
age
at
a
given
location
will
only
be
accurate
to
within
8
hours.
Furthermore,
the
proximity
of
sample
locations
to
one
another
will
also
affect
the
accuracy
of
the
study
results.
It
may
be
appropriate
to
space
samples
far
apart
on
large
transmission
mains,
but
within
the
distribution
system
(
which
contains
many
piping
and
hydraulic
interactions)
samples
should
be
located
closer
together.

Optimally,
tracer
studies
should
be
conducted
under
conditions
that
represent
high
DBP
formation
(
typically
summer
months).
Also,
the
study
should
be
detailed
enough
to
provide
good
characterization
of
the
entire
distribution
system.
Not
all
extremities
must
be
covered
by
the
study,
but
the
data
must
be
complete
enough
to
allow
for
a
reasonable
extrapolation
of
the
results
to
cover
the
entire
distribution
system.

Although
tracer
studies
often
provide
very
good
information,
they
can
be
time
consuming
and
costly.
Conducting
a
tracer
study
solely
for
the
IDSE
SMP
may
not
be
cost
effective.
However,
if
you
are
considering
a
tracer
study
for
some
other
purpose
(
e.
g.
calibration
of
a
water
distribution
system
model),
consideration
should
be
given
to
using
the
tracer
study
as
a
tool
for
the
IDSE
SMP.

Results
from
previously
conducted
tracer
studies
may
be
very
useful
in
identifying
areas
in
the
distribution
system
with
high
and
average
residence
times.
Typically,
the
study
should
have
been
conducted
within
the
past
10
years
and
represent
the
existing
distribution
system
configuration.
However,
if
your
system
has
implemented
operational
changes
that
permanently
and
significantly
changed
the
flow
of
water
through
your
distribution
system
(
i.
e.,
new
transmission
mains,
addition
of
large
industrial
users,
significant
development
in
formerly
unpopulated
or
remote
areas,
etc.)
since
your
tracer
study,
the
study
will
be
of
limited
use
in
selecting
SMP
sample
locations.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
35
If
you
have
recently
conducted
or
are
planning
to
conduct
a
detailed
tracer
study
of
your
system,
you
may
want
to
consider
completing
an
alternative
SSS
(
see
Chapter
3).

1)
High
TTHM
and
High
HAA5
Sites
High
residence
time
locations
should
be
identified
on
a
map
of
the
system
based
on
the
tracer
study
field
results.
SMP
sample
sites
should
be
chosen
from
the
area
or
areas
of
the
distribution
system
where
these
high
residence
time
tracer
study
sites
are
located.
The
SMP
sample
sites
do
not
have
to
be
chosen
at
the
exact
location
of
the
tracer
study
monitoring
sites,
just
in
the
general
area
identified
by
the
study.

When
selecting
high
TTHM
and
high
HAA5
sites
based
on
tracer
study
results
it
is
important
to
remember
that
residence
time
is
just
one
factor
in
identifying
high
TTHM
and
high
HAA5
sites.
Residence
time
estimates
should
be
compared
with
other
distribution
system
data
(
e.
g.,
disinfectant
residual
data)
before
making
your
final
sample
site
selections.
Areas
with
high
residence
time
but
low
or
no
disinfectant
residual
may
have
microbiological
activity
which
can
degrade
HAA5.
Consequently,
high
HAA5
sites
may
not
necessarily
be
located
at
areas
with
high
residence
times.

2)
Average
Residence
Time
The
residence
time
at
all
sites
sampled
during
the
tracer
test
field
effort
should
be
plotted
on
a
map
of
the
system.
The
overall
system
average
age
should
be
calculated
by
determining
the
median
residence
time
results
obtained
during
the
field
test.
Sites
with
residence
times
approximately
equal
to
the
median
of
tracer
study
results
should
be
identified
on
the
map
and
the
required
SMP
sample
sites
chosen
from
within
these
areas.

8.4.6
System
Operating
Data
System
operating
data,
such
as
pump
run
times,
pumping
rates,
tank
level
data
or
flow
rates,
metered
flows
between
pressure
zones,
and
demand
data
for
large
users
may
be
helpful
in
understanding
overall
water
flow
patterns
in
your
distribution
system.
For
example,
storage
tank
configuration
and
operation
can
have
a
significant
impact
on
maximum
and
average
residence
times
in
the
areas
of
a
system
"
downstream"
of
the
storage
tank.
Pumping
rates
and
flow
metering
between
pressure
zones
can
provide
a
direct
indication
of
the
movement
of
water
through
your
system.
A
review
of
billing
records
can
identify
your
largest
customers.
Areas
of
your
system
"
upstream"
of
your
largest
customers
are
likely
to
have
fresher
water
than
areas
downstream
of
these
customers.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
36
Distribution
System
Map
Residence
Time
(
Days)

Residual
Data
(
mg/
L)

DBP
Data
(
:
g/
L)
0.5
2.1
1.4
1.5
0.8
1.9
2.5
3.0
1.1
1.9
1.3
1.0
0.9
0.7
0.5
0.3
15
44
24
18
31
63
85
77
1.7
1.0
0.4
0.5
0.1
1.1
1.4
1.5
8.4.7
Geographic
Information
System
(
GIS)

Geographic
information
system
(
GIS)
software
is
capable
of
assembling,
storing,
manipulating,
and
displaying
geographically
referenced
data.
ArcView
and
Intergraph
are
examples
of
two
packages
currently
available.
GIS
allows
large
amounts
of
distribution
system
data
to
be
compiled
and
users
to
query
those
data
to
identify
areas
in
a
distribution
system
meeting
specified
criteria.
It
is
equivalent
to
plotting
various
data
on
individual
see­
through
maps
and
laying
those
maps
on
top
of
each
other
so
all
data
can
be
viewed
together
(
Figure
8.2
depicts
this
concept).

Figure
8.2
Conceptual
Diagram
of
GIS
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
37
Table
8.4
summarizes
the
data
storage
capabilities
of
a
typical
GIS
application.

Table
8.4
Summary
of
GIS
Data
Storage
Capabilities
General
System
Data
Structural
Data
Operational
Data
Water
Quality
Data
Land
uses
and
zoning
Population
density
Pipe
diameter
and
length
Valves
and
fittings
Pumps
Pipe
age
Pipe
material
Pipe
maintenance
history
Pipe
velocities
System
pressure
Pressure
zones
Residence
time
Temperature
Residual
disinfectant
Total
coliforms
HPC
DBPs
While
GIS
applications
can
be
a
valuable
tool
for
evaluating
many
types
of
distribution
system
data
geographically,
they
are
not
hydraulic
models
and
cannot
predict
system
conditions.
GIS
applications
are
a
framework
for
displaying
information
related
to
your
distribution
system.
This
means
residence
times,
system
pressures,
pipe
velocities,
and
other
operational
data
should
be
collected
by
some
other
method
(
e.
g.,
hydraulic
model
or
field
measurements)
and
entered
into
the
GIS
database.

After
hydraulic
and
water
quality
data
are
integrated
into
a
GIS
application,
users
can
query
the
data
to
locate
areas
which
meet
several
criteria
for
SMP
sites.
For
example,
a
user
may
request
locations
where
the
residence
time
exceeds
4
days,
the
free
chlorine
residual
is
between
0.2
and
0.5
mg/
L,
and
the
HPC
count
is
less
than
500
cfu/
mL.
Most
GIS
applications
can
highlight
those
locations
on
a
map
of
the
distribution
system.
The
user
can
then
select
geographically
diverse
locations
from
these
areas
for
the
purposes
of
IDSE
SMP
monitoring.

The
procedure
by
which
GIS
identifies
preliminary
SMP
sample
locations
is
similar
to
the
process
an
individual
might
use
if
they
were
doing
the
analysis
by
hand.
However,
GIS
is
capable
of
looking
at
a
larger
amount
of
data
in
an
integrated
manner,
without
the
excess
time
of
plotting
the
data
manually.
Purchasing
a
GIS
application
solely
for
the
purpose
of
conducting
the
IDSE
may
not
be
efficient
because
there
will
be
a
considerable
effort
involved
in
getting
the
system
up
and
running.
However,
if
your
system
currently
utilizes
or
is
planning
to
purchase
a
GIS
application,
consideration
should
be
given
to
using
the
application
as
a
tool
for
identifying
SMP
sites.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
38
8.5
Methodology
for
Selecting
Final
SMP
Sites
As
described
in
the
previous
section,
various
data
sources
and
tools
can
be
used
to
identify
SMP
sites,
but
some
may
provide
more
accurate
estimates
of
high
TTHM
and
HAA5
locations
or
average
residence
time
locations
than
others.
How
do
you
prioritize
the
data
and
combine
data
sources
and
tools
to
select
final
SMP
sites?
This
section
addresses
this
question
by
providing
general
guidelines
for
(
1)
identifying
all
possible
preliminary
SMP
sites
and
(
2)
narrowing
down
the
preliminary
sites
to
final
SMP
sites.
Detailed
guidance
for
identifying
preliminary
sites
using
each
data
source
or
tool
was
provided
in
section
8.4
 
this
section
focuses
on
combining
tools
to
select
preliminary
and
final
sites.

A
key
to
selecting
final
SMP
sites
is
the
ability
to
plot
preliminary
sites
on
a
detailed
map
of
your
distribution
system.
You
should
always
visually
confirm
that
SMP
sites
provide
geographic
coverage
of
the
distribution
system
and
are
in
expected
areas
of
high
and
average
residence
time
(
as
predicted
by
a
hydraulic
model
or
other
data
source)
and
that
you
are
not
missing
key
areas
that
may
not
have
been
sampled
in
the
past.
If
you
have
GIS
capabilities,
queries
can
be
extremely
useful
in
automating
the
site
selection
process.
In
particular,
GIS
queries
can
be
used
to
evaluate
multiple
data
sources
for
you
rather
than
having
you
perform
the
time
consuming
process
of
evaluating
multiple
parameters
by
hand
or
in
a
spreadsheet.

The
information
and
considerations
presented
in
this
section
are
not
intended
to
be
limiting
or
prescriptive.
EPA
recognizes
DBP
formation
is
system­
specific
and
the
guidance
provided
in
this
manual
will
not
apply
to
every
system.
The
operational
experience
and
knowledge
of
system
personnel
and
all
available
information
should
be
considered
in
selecting
SMP
sample
sites.
Best
professional
judgement
should
be
exercised
in
the
specific
application
of
guidelines
in
this
manual.

8.5.1
Identifying
Preliminary
Sites
Using
Combinations
of
Tools
and
Data
Sources
This
section
contains
a
multi­
step
process
that
allows
you
to
use
any
combination
of
the
following
data
sources
with
maps
to
select
preliminary
sites:

°
Water
distribution
system
model
outputs
°
Tracer
study
results
°
Disinfectant
residual
data
°
DBP
data
All
steps
involve
plotting
preliminary
sites
on
a
map
of
your
distribution
system.
Figure
8.3
is
flow­
chart
that
indicates
at
which
step
you
should
start,
depending
on
your
available
data
sources.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
39
Do
you
have
a
water
model
or
tracer
study?
Start
at
Step
1
Do
you
DBP
Data?
Start
at
Step
2
Yes
No
Do
you
Disinfection
Residual
Data?
Start
at
Step
3
Yes
No
Start
at
Step
4
No
Yes
Figure
8.3
Starting
Point
for
Preliminary
Site
Selection
The
steps
in
this
section
focus
on
identifying
preliminary
high
TTHM
and
high
HAA5
sites
at
locations
of
high
residence
time.
Guidance
for
selecting
average
residence
time
sites
(
for
100
percent
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
40
purchasing
systems
serving
at
least
10,000
people
and
for
producing
surface
water
serving
at
least
10,000)
is
presented
separately
at
the
end
of
each
step.

Step
1
­
Using
Modeling
and
Tracer
Study
Results
Identifying
Preliminary
High
TTHM
and
High
HAA5
Sites
Residence
Time
Sites
Use
output
from
your
water
distribution
system
model
or
tracer
study
results
to
identify
areas
with
the
highest
residence
times.
You
should
identify
at
least
twice
as
many
preliminary
SMP
sites
as
required.
For
example,
from
Table
8.1
producing
ground
water
systems
serving
500
to
9,999
people
must
have
one
high
TTHM
and
one
high
HAA5
site
per
plant
for
the
SMP;
therefore,
they
should
select
at
least
two
preliminary
high
TTHM
sites
and
two
preliminary
high
HAA5
sites
per
plant
using
model
or
tracer
study
data.
Plot
all
preliminary
sites
on
a
map
of
your
distribution
system.

Identifying
Preliminary
Average
Residence
Time
Sites
Use
output
from
your
water
distribution
system
model
or
tracer
study
results
to
identify
areas
with
average
residence
times.
You
should
identify
at
least
twice
as
many
preliminary
SMP
sites
as
required.

C
For
100
percent
purchasing
systems
serving
at
least
10,000
people,
see
Table
8.1
for
the
number
of
average
residence
time
sites
that
are
required
for
the
SMP.
(
100
percent
purchasing
systems
serving
less
than
10,000
people
do
not
have
to
select
average
residence
time
sites).

C
For
producing
systems
providing
surface
water
in
whole
or
in
part,
at
least
four
preliminary
sites
per
plant
should
be
identified
(
two
SMP
sites
per
plant
are
required).
Plot
all
preliminary
average
residence
time
sites
on
a
map
of
your
distribution
system.

Step
2
­
Using
TTHM
and
HAA5
Data
Note:
DBP
data
are
generally
not
useful
in
identifying
average
residence
time
sites.
Only
preliminary
high
TTHM
and
high
HAA5
sites
are
covered
in
this
step.

If
you
completed
Step
1:

Determine
if
the
high
TTHM
and
HAA5
locations
correspond
to
areas
with
high
water
residence
time.
It
is
possible
that
the
water
distribution
system
model
or
tracer
study
did
not
capture
mixing
effects
or
other
factors
leading
to
higher
residence
times
than
predicted.
If
the
high
TTHM
and
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
41
HAA5
data
occur
outside
predicted
areas
of
high
residence
time,
you
should
select
additional
preliminary
sites
to
cover
these
areas.

If
you
did
not
complete
Step
1:

Review
TTHM
and
HAA5
data
and
identify
areas
with
the
highest
TTHM
and
HAA5
concentrations
(
and/
or
areas
with
similar
characteristics
to
sites
with
high
TTHM
and
HAA5
concentrations).
Plot
these
areas
on
your
distribution
system
map.

Step
3
­
Using
Disinfectant
Residual
Data
If
you
completed
Step
1:

Identifying
preliminary
high
TTHM
and
high
HAA5
sites
residence
time
sites:

On
a
map
of
your
system,
identify
areas
with
low
disinfectant
residual
concentration
compared
to
finished
water.
(
It
may
be
helpful
to
record
the
average
concentration
for
the
summer
months
or
the
minimum
monthly
concentration
on
a
map
of
you
system).
Determine
if
the
areas
with
high
residence
times
identified
in
Step
1
correspond
to
areas
with
low
disinfectant
residuals.
(
Note,
the
use
of
booster
disinfection
will
affect
this
correlation.)
It
is
not
unusual
for
disinfectant
residual
data
to
show
different
trends
compared
to
hydraulic
model
outputs.
It
is
possible
that
a
hydraulic
model
or
tracer
study
did
not
capture
mixing
effects
or
other
factors
leading
to
higher
residence
times
than
predicted.
Disinfectant
residual
can
be
influenced
by
other
factors,
such
as
internal
corrosion,
biological
activity,
etc.
(
refer
to
section
8.4.2.1
for
a
more
complete
description
of
other
factors
affecting
disinfectant
residual
decay).
Thus,
low
disinfectant
residual
is
not
a
definitive
indication
of
long
residence
time.

If
areas
with
low
disinfectant
residuals
are
identified
outside
predicted
areas
of
high
residence
time,
you
may
wish
to
select
additional
preliminary
SMP
sites
to
cover
these
areas.
For
preliminary
high
HAA5
sites,
a
minimum
residual
of
0.2
mg/
L
chlorine
or
0.5
mg/
L
chloramine
should
be
present.

Identifying
preliminary
average
residence
time
sites:

On
a
map
of
your
system,
identify
areas
of
average
residence
time
based
on
disinfectant
residual
data.
(
See
section
8.4.2.1
for
guidance
on
identifying
areas
of
average
residence
time
using
disinfectant
residual
data.)
Do
average
residence
time
sites
identified
by
your
water
distribution
system
model
or
tracer
study
in
Step
1
correspond
with
average
residence
time
sites
identified
by
evaluating
disinfectant
residual
data?
Identify
additional
preliminary
SMP
sites
for
average
residence
times
if
your
residual
data
show
different
locations
than
results
from
your
model
or
tracer
study.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
42
If
you
did
not
complete
Step
1:

Identifying
preliminary
high
TTHM
and
high
HAA5
sites
residence
time
sites
Evaluate
your
disinfectant
residual
data
from
warmer
months
and
identify
areas
with
the
lowest
or
no
residual
concentrations.
These
locations
are
likely
those
with
the
highest
residence
time,
and
represent
potential
locations
for
high
TTHM
and
HAA5
SMP
sites.
(
High
HAA5
sites
should
be
limited
to
those
sites
with
a
free
chlorine
residual
of
at
least
0.2
mg/
L
or
a
chloramine
residual
of
at
least
0.5
mg/
L.)
Identify
at
least
twice
as
many
SMP
sites
as
required.
Plot
these
areas
on
your
distribution
system
map.

Identifying
preliminary
average
residence
time
sites
Using
disinfectant
residual
data
from
your
TCR
monitoring
locations
(
and
flow
data,
if
available),
calculate
the
average
system
and
locational
average
disinfectant
residuals.
Section
8.4.2.1
discusses
these
methodologies.
Identify
those
locations
with
average
disinfectant
residuals
approximately
equal
to
the
system
average.
Identify
at
least
twice
as
many
preliminary
SMP
sites
as
required.
Plot
these
areas
on
your
distribution
system
map.

Step
4
­
Map
Review
Review
your
water
distribution
system
map
to
identify
additional
preliminary
SMP
locations
representative
of
high
TTHMs
and
high
HAA5
not
identified
in
Steps
1
through
3
where:

°
There
is
light
development
or
low
residential
population
far
away
from
a
treatment
plant
°
An
area
is
served
by
one
or
more
distribution
system
storage
facilities,
especially
if
the
storage
facility(
s)
have
high
water
residence
times
°
An
area
is
served
by
booster
disinfection
stations
You
should
not
select
preliminary
sites
at
the
very
end
of
a
water
main
past
the
last
customer.
A
better
location
would
be
at
the
last
group
of
customers.

8.5.2
Selecting
Final
SMP
Sites
from
Preliminary
Sites
The
following
are
general
guidelines
for
choosing
final
SMP
sites
from
your
list
of
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
43
preliminary
sites
identified
in
accordance
with
section
8.5.1.
Specific
guidelines
for
very
small
systems
serving
less
than
500
people
are
at
the
end
of
section
8.5.2.1.
EPA
recognizes
there
are
systemspecific
factors
that
may
lead
you
to
select
final
sites
that
do
not
specifically
meet
these
guidelines.
If
you
deviate
from
the
guidelines,
provide
justification
to
your
State
in
your
IDSE
Report.

8.5.2.1
Selecting
High
TTHM
and
HAA5
SMP
Sites
(
All
Systems)

1)
Select
SMP
sites
in
hydraulically
different
areas
(
i.
e.,
do
not
select
two
sites
close
to
one
another).

2)
Select
SMP
sites
in
geographically
different
areas
and
separated
from
existing
Stage
1
DBPR
sites.

3)
Prioritize
sites
that
meet
the
most
siting
criteria
and
those
identified
based
on
more
than
one
data
source.
For
example,
a
preliminary
high
TTHM
site
that
has
low
disinfectant
residual,
is
near
the
edge
of
the
distribution
system
and
is
downstream
of
a
tank
would
be
a
likely
SMP
site.

4)
Select
high
TTHM
sites
located
after
storage
facilities
and
booster
disinfection
stations.

5)
Select
high
TTHM
sites
in
areas
with
the
lowest
or
no
residual
disinfectant
(
unless
your
system
uses
booster
disinfection).

6)
Generally,
select
high
HAA5
sites
with
a
minimum
of
0.2
mg/
L
chlorine
residual
or
0.5
mg/
L
chloramine
residual
for
all
observations.

7)
Locate
at
least
one
of
your
high
TTHM
sites
in
a
remote
area
of
your
distribution
system.
If
you
are
only
required
to
select
one
high
TTHM
site,
it
is
strongly
recommended
that
you
locate
this
site
away
from
the
treatment
plant,
near
the
last
group
of
customers
(
but
prior
to
the
last
fire
hydrant).

8)
DBP
data
are
important
as
long
as
they
represent
your
current
system
configuration.
If
you
have
a
historical
TTHM
or
HAA5
data
in
an
area,
these
data
can
be
used
to
prioritize
sites
(
or
select
one
over
another)
when
other
data
shows
no
difference
between
the
sties.
For
example,
if
disinfectant
residual
data
are
the
same
for
three
sites
over
the
same
periods,
then
the
DBP
data
can
be
used
to
select
a
high
TTHM/
HAA5
site.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
44
Special
Considerations
for
Storage
Tanks
9)
Understanding
the
impact
of
storage
tanks
on
water
movement
and
water
age
in
a
distribution
system
is
complicated
by
a
variety
of
specific
physical
and
operational
characteristics.
The
mixing
characteristics
of
storage
tanks
are
impacted
by
the
inlet/
outlet
piping
configuration,
inlet
momentum,
temperature,
and
duration
of
drain/
fill
cycles.
For
example,
horizontal
inlets
at
the
base
of
storage
tanks,
oversized
inlet
piping
which
results
in
low
inlet
momentum,
and
short
drain/
fill
cycles
are
all
potential
causes
of
poor
mixing
in
storage
tanks.
A
methodology
for
evaluating
storage
tank
mixing
characteristics
is
presented
in
Water
Quality
Modeling
of
Distribution
System
Storage
Facilities
(
Grayman
et
al.
2000).

Tanks
with
poor
mixing
characteristics
and
common
inlet/
outlet
piping
may
operate
in
a
"
last
in
 
first
out"
mode,
meaning
that
the
freshest
water
in
the
tank
is
the
first
to
be
discharged
during
a
drain
cycle.
During
periods
of
higher
than
normal
demand,
when
drain
periods
may
be
extended,
these
tanks
may
discharge
water
from
the
upper
regions
of
the
tank
where
water
age
is
substantially
(
e.
g.,
several
days
or
weeks)
higher
than
water
in
the
lower
regions
of
the
tank.
If
you
suspect
poor
mixing
in
one
or
more
of
your
storage
tanks,
areas
receiving
the
stored
water
from
those
tanks
may
occasionally
have
high
DBP
concentrations.

Tank
level
data
can
be
used
to
assess
the
theoretical
average
residence
time
of
water
in
a
tank;
however,
the
mixing
characteristics
of
the
tank
must
be
thoroughly
understood
to
adequately
estimate
the
true
average
water
age
in
a
storage
tank
(
Uber
et
al.
2002).
It
is
important
to
understand
that
distribution
system
storage
facilities
can
have
significant
but
variable
impacts
on
water
age.
As
a
result,
high
TTHM
and
HAA5
sites
should
typically
be
located
downstream
of
distribution
system
storage
facilities.

Specific
Guidance
for
Systems
Serving
Less
Than
500
People
10)
Select
a
high
TTHM
site
in
a
high
residence
time
area
that
is
not
near
your
Stage
1
DBPR
site.
(
Your
Stage
1
DBPR
site
should
be
located
in
an
area
of
your
distribution
system
that
represents
your
maximum
residence
time.)

11)
Locate
your
high
HAA5
site
in
a
location
other
than
near
your
high
TTHM
and
Stage
1
DBPR
sites.
If
those
two
sites
cover
the
high
residence
time
areas
of
your
distribution
system,
then
select
a
site
in
an
area
with
average
residence
time
(
see
section
8.4.2.1
for
determining
average
residence
time
based
on
disinfectant
residual
data)
for
your
high
HAA5.
The
highest
HAA5
concentrations
may
not
occur
at
the
highest
residence
time
locations.
There
may
be
system­
specific
factors
that
cause
HAA5
to
biodegrade
and,
therefore,
areas
with
average
residence
time
may
have
the
highest
HAA5
concentrations.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
45
8.5.2.2
Selecting
Average
Residence
Time
Sites
SMP
sites
representing
average
residence
time
are
required
for:

C
100
percent
purchasing
systems
serving
at
least
10,000
people
C
Producing
surface
water
systems
serving
at
least
10,000
people
From
the
preliminary
average
residence
time
sites,
select
final
average
residence
time
sites
that
are
geographically
diverse
from
the
other
SMP
sites
and
existing
Stage
1
DBPR
average
residence
time
compliance
sampling
sites.

8.6
Stage
2B
DBPR
Site
Selection
and
IDSE
Reporting
Requirements
(
40
CFR
141.605)

Once
the
SMP
monitoring
period
has
ended,
the
Stage
2B
compliance
monitoring
sites
can
be
selected
from
the
SMP
and
Stage
1
DBPR
results
(
or
Stage
2A
DBPR
for
systems
on
the
late
IDSE
schedule).
Selection
must
be
based
on
the
average
TTHM
and
HAA5
concentrations
measured
over
the
SMP
monitoring
period
at
each
site,
or
locational
running
annual
averages
(
LRAAs).
Tables
8.5
and
8.6
summarize
the
Stage
2B
site
requirements
for
100
percent
purchasing
and
producing
systems,
respectively.

TTHM
and
HAA5
LRAAs
are
the
most
important
factors
to
consider
when
selecting
Stage
2B
DBPR
monitoring
locations.
However,
the
rule
allows
for
some
flexibility
in
selecting
Stage
2B
compliance
sites.
Other
factors
should
be
considered
and
may
lead
to
selecting
a
site
with
a
slightly
lower
LRAA
over
another
site.
The
following
conditions
are
possible
reasons
why
you
may
select
a
site
with
a
lower
LRAA
over
another
site:

°
The
site
provides
for
more
complete
geographic
coverage
of
the
entire
distribution
system
°
The
site
allows
you
to
maintain
an
historical
record
°
Sampling
at
that
site
provides
the
opportunity
to
collect
other
water
quality
or
operational
data
(
e.
g.,
chloramine
systems
may
want
to
collect
nitrate
data
at
that
location)
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
1The
Stage
2
DBPR
does
not
specify
a
difference
between
two
LRAAs
that
allows
selection
of
a
site
with
the
lower
LRAA
for
Stage
2B.
EPA
recognizes
there
is
uncertainty
and
variability
associated
with
the
TTHM
and
HAA5
data
quality.
While
the
LRAA
calculation
reduces
the
impact
of
these
to
some
extent,
they
can
cause
a
small
difference
between
two
LRAAs
to
be
statistically
insignificant
and
thus,
making
the
selection
of
the
Stage
2B
site
dependent
on
other
factors.
The
intent
of
the
Stage
2
DBPR
is
to
reduce
peak
DBP
concentrations
in
the
distribution
system.
You
should
use
best
professional
judgment
to
select
Stage
2B
sites
with
consideration
to
the
intent
of
the
rule
and
demonstrate
to
the
State
the
reason
for
the
selection.

July
2003
­
Proposal
Draft
All
Systems
8­
46
If
you
do
not
use
your
highest
TTHM
and
HAA5
LRAAs
to
select
your
Stage
2B
DBPR
sites,
you
must
provide
justification
for
your
selection
in
your
IDSE
report.
1
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
47
Table
8.5
Stage
2B
Compliance
Monitoring
Requirements
for
100
Percent
Purchasing
Systems1,2
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
location
type)
per
System
Total
Number
of
Sites
per
System
Monitoring
Frequency4
Stage
1
Average
Residence
Time
Site
Highest
TTHM
Highest
HAA5
Surface
Water
Systems5
<
500
­
1
1
25
Every
365
days
500
­
4,999
­
1
1
25
Every
90
days
5,000
­
9,999
­
1
1
2
Every
90
days
10,000
­
24,999
1
2
1
4
Every
90
days
25,000
­
49,999
1
3
2
6
Every
90
days
50,000
­
99,999
2
4
2
8
Every
90
days
100,000
­
499,999
3
6
3
12
Every
90
days
500,000
­
1,499,999
4
8
4
16
Every
90
days
1.5
million
­
<
5
million
5
10
5
20
Every
90
days
>
5
million
6
12
6
24
Every
90
days
Ground
Water
Systems
<
500
­
1
1
26
Every
365
days
500
­
9,999
­
1
1
2
Every
365
days
10,000
­
99,999
1
2
1
4
Every
90
days
100,000
­
499,999
1
3
2
6
Every
90
days
>
500,000
2
4
2
8
Every
90
days
1
(
40
CFR
141.605
(
e))

2
For
the
purpose
of
this
guidance
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.
3
Population
served
is
usually
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
4
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location,
unless
otherwise
noted.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
5
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
6
Dual
sample
sets
are
not
required
at
both
the
high
TTHM
and
the
high
HAA5
site
 
if
the
highest
TTHM
and
HAA5
levels
occur
at
a
different
locations,
then
only
one
sample
is
collected
at
each
location.
If
they
occur
at
the
same
location,
then
a
dual
sample
set
is
collected
at
that
location.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
48
Table
8.6
Summary
of
Stage
2B
Compliance
Monitoring
Requirements
for
Producing
Systems1,2
System
Size
(
Population
Served3)
Number
of
Distribution
System
Sites
(
by
location
type)
per
Plant4
Total
Number
of
Sites
per
Plant
Monitoring
Frequency5
Stage
1
Average
Residence
Time
Site
Highest
TTHM
Highest
HAA5
Surface
Water
Systems6
<
500
­
1
1
27
Every
365
days
500
­
9,999
­
1
1
2
Every
90
days
>
10,000
1
2
1
4
Every
90
days
Ground
Water
Systems
<
500
­
1
1
27
Every
365
days
500
­
9,999
­
1
1
2
Every
365
days
>
10,000
­
1
1
2
Every
90
days
1
(
40
CFR
141.605
(
a))

2
For
the
purpose
of
this
guidance
manual,
producing
systems
are
those
that
do
not
buy
100
percent
of
their
water
year­
round
(
i.
e.,
they
produce
some
or
all
of
their
own
finished
water).
3
Population
served
is
usually
a
system's
retail
population.
It
should
not
include
populations
served
by
consecutive
systems
that
purchase
water
from
that
system.
4
For
the
purpose
of
the
Stage
2
DBPR
compliance
monitoring,
a
plant
can
be
either
a
treatment
plant
(
that
provides,
at
a
minimum,
disinfection
using
a
disinfectant
other
than
UV)
or
a
consecutive
system
entry
point
that
operates
for
at
least
60
consecutive
days
per
year.
5
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.
A
dual
sample
set
must
be
collected
at
each
location,
unless
otherwise
noted.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.
6
For
the
purpose
of
this
guidance
manual,
"
surface
water
systems"
are
equivalent
to
subpart
H
systems
(
i.
e.,
any
system
that
uses
surface
water
or
GWUDI
as
a
source,
including
all
mixed
systems
that
use
some
surface
water
or
GWUDI
and
some
ground
water).
7
Dual
sample
sets
are
not
required
at
both
the
high
TTHM
and
the
high
HAA5
site
 
if
the
highest
TTHM
and
HAA5
levels
occur
at
a
different
locations,
then
only
one
sample
is
collected
at
each
location.
If
they
occur
at
the
same
location,
then
a
dual
sample
set
is
collected
at
that
location.

8.6.1
100
Percent
Purchasing
Systems
The
rule
requires
100
percent
purchasing
systems
to
use
the
following
protocol
for
selecting
Stage
2B
sites
from
IDSE
and
Stage
1
compliance
monitoring
data.

1)
Site
with
the
highest
TTHM
LRAA
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
49
2)
Site
with
the
highest
HAA5
LRAA
(
not
previously
selected)

3)
Existing
Stage
1
DBPR
compliance
monitoring
site
4)
Site
with
the
highest
TTHM
LRAA
(
not
previously
selected)

Repeat
the
protocol,
selecting
from
the
remaining
sites,
until
the
required
number
has
been
selected.
For
#
3,
alternate
between
highest
HAA5
and
highest
TTHM
of
Stage
1
DBPR
average
residence
time
sites,
not
previously
selected.

8.6.2
Producing
Systems
The
rule
requires
producing
systems
to
select
the
required
amount
of
sites
for
each
plant
using
the
following
protocols:

Large
surface
water
systems
For
each
plant,
select
sites
with
following:

1)
Highest
TTHM
LRAA
2)
Highest
TTHM
LRAA
3)
Highest
HAA5
LRAA
4)
Existing
Stage
1
DBPR
Average
Residence
Time
site
with
the
highest
TTHM
or
HAA5
LRAA.
If
you
do
not
have
a
Stage
1
Average
Residence
Time
site,
then
you
must
choose
the
next
highest
HAA5
site.

Small
surface
water
systems
and
all
ground
water
systems
Select
sites
with
the
highest
TTHM
LRAA
and
HAA5
LRAA
for
each
plant.

°
Systems
serving
500
to
less
than
10,000
people
 
if
the
highest
TTHM
and
HAA5
occur
at
the
same
site
for
a
given
plant,
then
your
system
may
monitor
at
only
that
site
for
that
plant.

°
Systems
serving
less
than
500
 
you
are
required
to
take
one
TTHM
and
one
HAA5
sample
per
year
per
plant.
If
the
high
TTHM
and
HAA5
for
a
given
plant
occurred
at
different
sites,
then
you
only
need
to
collect
a
TTHM
sample
at
the
high
TTHM
site
and
a
HAA5
sample
at
the
high
HAA5
site.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
50
8.6.3
Examples
of
Stage
2B
DBPR
Site
Selection
This
section
provides
examples
of
Stage
2B
DBPR
site
selection:

Example
8.15
Selecting
Stage
2B
DBPR
Sites
from
SMP
Data
Example
8.16
Maintaining
an
Historical
Record
Example
8.17
Providing
Geographical
Coverage
When
Choosing
Stage
2B
DBPR
Sites
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
51
Example
8.15
Selecting
Stage
2B
DBPR
Sites
from
SMP
Data
A
producing
system
serves
90,000
people
and
has
one
surface
water
treatment
plant.
This
system
must
select
four
Stage
2B
DBPR
compliance
sites
(
from
Table
8.9):
two
high­
TTHM
sites;
one
high­
HAA5
site;
and
one
from
the
three
existing
Stage
1
DBPR
average
residence
time
compliance
sites.
The
table
below
lists
the
TTHM
and
HAA5
LRAAs
for
all
Stage
1
DBPR
compliance
monitoring
sites
and
three
of
the
eight
SMP
sites
(
these
data
represent
the
seven
highest
TTHM
and
HAA5
LRAAs).

Site
TTHM
LRAAs
HAA5
LRAAs
A
(
Stage
1
max.
residence
time)
64
39
B
(
SMP
high
TTHM
site)
66
40
C
(
SMP
high
HAA5
site)
72
52
D
(
SMP
high
TTHM
site)
76
50
E
(
Stage
1
avg.
residence
time)
57
48
F
(
Stage
1
avg.
residence
time)
42
30
G
(
Stage
1
avg.
residence
time)
55
50
Selecting
the
Average
Residence
Time
Site
The
average
residence
time
site
should
have
either
the
highest
TTHM
or
highest
HAA5
LRAA
of
the
Stage
1
DBPR
average
residence
time
sites.
The
water
system
may
choose
either
Site
E
(
highest
TTHM
LRAA)
or
Site
G
(
highest
HAA5
LRAA).
With
two
valid
options,
the
site
providing
the
best
geographic
coverage
is
preferred.
Site
G
is
located
downstream
of
an
elevated
tank
and
is
the
only
site
that
receives
water
from
that
tank;
therefore,
the
water
system
selects
Site
G.

Selecting
High­
TTHM
and
High­
HAA5
Sites
Sites
C
and
D
have
both
the
highest
TTHM
and
HAA5
LRAAs
(
they
can
represent
the
two
high­
TTHM
sites
or
one
high­
TTHM
site
and
one
high­
HAA5).
One
more
high
TTHM
or
high
HAA5
site
must
be
chosen
between
Sites
A
and
B.
The
differences
in
LRAAs
between
Site
A
and
Site
B
are
minimal.
Site
A
was
first
selected
as
a
THM
Rule
"
maximum"
compliance
site
and
is
now
a
Stage
1
site
DBPR.
To
maintain
the
historic
record
of
sampling,
Site
A
is
chosen.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
52
Example
8.16
Maintaining
an
Historical
Record
A
producing
system
serves
4,000
people
and
has
one
ground
water
treatment
plant.
This
system
must
select
two
Stage
2B
compliance
sites
(
from
Table
8.9):
one
high­
TTHM
and
one
high­
HAA5
site.
A
comparison
of
SMP
and
Stage
1
DBPR
compliance
monitoring
results
are
presented
in
the
table
below.

Sample
Locations
with
Highest
LRAAs
LRAA
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

SMP
#
1
High
TTHM
72
51
SMP
#
2
High
TTHM
65
56
SMP
#
3
High
HAA5
60
51
Stage
1
DBPR
max
residence
time
site
70
51
Because
the
TTHM
LRAA
for
the
Stage
1
DBPR
site
is
only
slightly
lower
than
the
maximum
TTHM
LRAA
(
SMP
#
1),
the
system
chooses
the
Stage
1
DBPR
site
over
SMP
#
1
for
the
Stage
2B
DBPR
high
TTHM
site
to
maintain
the
historic
DBP
record
at
that
site.
SMP
#
2
is
selected
as
the
high
HAA5
site.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
53
8.7
Reporting
Results
to
the
State
The
rule
requires
the
following
data
and
information
be
included
in
your
IDSE
report
to
the
State
(
40
CFR
141.604):

°
The
original
SMP
plan
and
an
explanation
of
any
deviations
from
that
plan
°
All
TTHM
and
HAA5
analytical
results
from
the
SMP
°
All
TTHM
and
HAA5
analytical
results
from
Stage
1
DBPR
compliance
samples
collected
during
the
period
of
the
IDSE
°
A
schematic
of
your
distribution
system
with
the
results,
location,
and
date
of
all
IDSE
SMP
and
compliance
samples
noted
°
Data
used
to
justify
IDSE
SMP
site
selections
°
Proposed
Stage
2B
compliance
monitoring
sites
with
justification
for
selection
of
each
proposed
site
°
Proposed
month(
s)
during
which
Stage
2B
monitoring
is
to
be
conducted
Water
Treatment
Plant
A
B
C
Example
8.17
Providing
Geographic
Coverage
When
Choosing
Stage
2B
DBPR
Sites
In
general,
the
two
representative
high
TTHM
sites
(
per
plant)
should
not
be
from
the
same
area
of
the
distribution
system.

The
two
highest
TTHM
LRAAs
in
the
distribution
system
are
from
adjacent
SMP
sample
sites
(
Sites
A
and
B).
The
site
with
the
third
highest
TTHM
LRAA
is
on
the
far
side
of
the
distribution
system
(
site
C).
In
this
case,
consider
selecting
sites
A
and
C
or
B
and
C
as
Stage
2B
DBPR
sites
for
a
broader
geographical
coverage
of
the
distribution
system.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
All
Systems
8­
54
Refer
to
Appendices
E
through
J
for
example
IDSE
reports
based
on
source
water
and
system
size
(
see
Table
8.10).

Remember
that
TTHM
and
HAA5
data
collected
for
the
SMP
are
not
to
be
included
in
compliance
calculations
for
the
Stage
1
or
Stage
2A
DBPR.
Also,
results
from
the
SMP
should
not
be
reported
in
your
Consumer
Confidence
Report.

If
you
do
not
receive
notification
that
your
Stage
2B
site
selection
was
acceptable
by
[
3
years
after
rule
promulgation]
for
systems
on
the
early
schedule
or
[
6
years
after
rule
promulgation]
for
systems
on
the
late
schedule,
you
should
contact
your
State
to
verify
your
Stage
2B
sites
meet
compliance
requirements.

Table
8.7
Example
IDSE
Reports
Appendix
System
Characteristics
Appendix
E
SMP
for
Producing
Surface
Water
System
(>
10,000)

Appendix
F
SMP
for
Producing
Ground
Water
System
(>
10,000)

Appendix
G
SMP
for
Producing
Surface
Water
System
(
500
­
9,999)

Appendix
H
SMP
for
Producing
Ground
Water
System
(<
10,000)

Appendix
I
SMP
for
Producing
Surface
Water
System
(<
500)

Appendix
J
SMP
for
100
Percent
Purchasing
Surface
Water
System
Appendix
A
Impacts
of
an
Alternative
Population­
Based
Monitoring
Approach
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
A­
1
A.
1
Introduction
The
Stage
2
DBPR
includes
monitoring
requirements
that
were
recommended
by
the
Stage
2
M­
DBP
Federal
Advisory
Committee
(
Stage
2
FACA)
in
the
Agreement
in
Principle
(
USEPA
2000).
Many
of
these
monitoring
requirements
were
based
on
those
in
the
1979
TTHM
Rule
and
Stage
1
DBPR.
For
example,
the
frequency
of
monitoring
under
the
Stage
1
DBPR
is
a
function
of
source
water
type
(
ground
or
surface
water),
size
of
system,
and
the
number
of
plants
per
system.
For
the
Stage
2
DBPR,
as
under
the
Stage
1
DBPR,
the
Stage
2
FACA
recommended
that
compliance
sampling
be
required
on
a
per­
plant
basis.
This
recommendation
is
based
on
the
assumption
that
as
systems
increase
in
size,
they
will
tend
to
have
more
plants
and
increased
complexity
of
water
treatment
and
distribution,
thereby
warranting
increased
monitoring
to
represent
DBP
occurrence
in
the
distribution
system.
The
Stage
2
FACA
also
recommended
higher
frequency
monitoring
for
systems
using
surface
water
than
those
using
ground
water
because
ground
water
tends
to
have
lower
and
more
stable
concentrations
of
organic
DBP
precursors
than
surface
water.
Furthermore,
since
many
ground
water
systems
have
multiple
wells/
entry
points
drawing
water
from
the
same
aquifer,
the
Stage
2
FACA
recommended
that
these
wells
be
considered
as
a
single
plant
with
the
same
monitoring
requirements
prescribed
for
one
plant,
if
approved
by
the
State.

Upon
further
analysis
of
the
Stage
2
FACA
recommendations,
EPA
has
identified
the
following
issues
related
to
the
monitoring
requirements
of
the
Stage
2
DBPR:

°
Basing
increased
monitoring
on
numbers
of
water
treatment
plants
per
system,
as
opposed
to
population
alone,
may
result
in
either
excessive
or
insufficient
samples
to
represent
DBP
occurrence
in
the
distribution
system.

°
The
proposed
sampling
requirements
for
mixed
systems
(
i.
e.,
those
receiving
surface
water
and
disinfecting
ground
water
in
their
distribution
system)
may
be
excessive,
depending
upon
the
system's
characteristics.

°
The
proposed
monitoring
requirements,
based
on
additional
samples
per
water
treatment
plant,
pose
unique
implementation
issues
for
systems
with
temporary
supplies
during
the
year.

To
address
these
issues,
the
Stage
2
DBPR
uses
two
approaches
to
monitoring
for
two
different
groups
of
systems:

1)
The
plant­
based
approach
is
dependent
on
population
served,
source
water,
AND
the
number
of
plants
in
a
system
(
as
with
Stage
1
DBPR
compliance
monitoring)
and
applies
to
systems
that
produce
some
or
all
of
their
own
finished
water
(
called
producing
systems
in
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
A­
2
this
manual).
For
the
purpose
of
the
Stage
2
DBPR,
a
plant
can
be
either
a
treatment
plant
(
that
provides,
at
a
minimum,
disinfection
using
a
disinfectant
other
than
UV)
or
a
consecutive
system
entry
point
that
operates
for
at
least
60
consecutive
days
per
year.

°
The
population­
based
approach
that
is
dependent
on
population
served
and
source
water
and
applies
to
only
those
systems
that
purchase
100
percent
of
their
finished
water
from
other
systems
(
called
100
percent
purchasing
systems
in
this
manual).

Section
V(
F)(
2)
of
the
Stage
2
DBPR
preamble
describes
the
monitoring
issues
in
detail
and
requests
comment
on
them,
particularly
the
significance
of
a
plant­
based
(
the
proposed
monitoring
scheme)
versus
a
population­
based
monitoring
approach
(
monitoring
requirements
based
on
population
and
source
type
only).

The
purpose
of
this
Appendix
is
to
describe
how
this
guidance
manual
would
be
revised
if
the
Stage
2
monitoring
scheme
were
changed
to
a
population­
based
approach.
First,
section
A.
2
presents
EPA's
proposed
framework
for
an
alternative
population­
based
monitoring
scheme.
Section
A.
3
then
discusses
a
revised
organization
and
consolidation
of
chapters
for
this
guidance
manual
to
reflect
a
population­
based
approach
monitoring
scheme
for
all
systems.

A.
2
Summary
of
Alternative
Population­
Based
Approach
The
Stage
2
DBPR
requires
monitoring
for
(
1)
the
IDSE
and
(
2)
Stage
2A
and
Stage
2B
compliance.
Currently,
monitoring
requirements
are
based
on
population
and
source
water
only
for
100
percent
purchasing
systems,
and
based
on
population,
source
water,
and
number
of
plants
for
producing
systems.
Under
the
alternative
population­
based
approach,
the
proposed
monitoring
requirements
for
100
percent
purchasing
systems
would
be
applied
to
all
systems.
The
following
exhibits
summarize
the
IDSE
and
Stage
2B
monitoring
requirements
for
the
population
based
approach.
(
These
requirements
are
identical
to
those
presented
in
Chapters
1,
4,
and
8
for
100
percent
purchasing.)

°
Table
A.
1
 
IDSE
SMP
monitoring
requirements
for
Population­
based
Approach
°
Table
A.
2
 
Stage
2B
routine
samples
required
for
Population­
based
Approach
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
A­
3
Table
A.
1
IDSE
SMP
Sampling
Requirements
for
Population­
based
Approach
System
Size
(
Population
Served)
Number
of
Distribution
System
Sites2
(
by
location
type)
per
System
Total
Number
of
Sites
per
System
Monitoring
Frequency
for
the
1­
year
IDSE
period4
Near
Entry
Point3
Average
Residence
Time
High
TTHM
High
HAA5
Surface
Water
Systems5
<
500
­
­
1
1
2
Every
180
days
500
­
4,999
­
­
1
1
2
Every
90
days
5,000
­
9,999
­
1
2
1
4
Every
90
days
10,000
­
24,999
1
2
3
2
8
Every
60
days
25,000
­
49,999
2
3
4
3
12
Every
60
days
50,000
­
99,999
3
4
5
4
16
Every
60
days
100,000
­
499,999
4
6
8
6
24
Every
60
days
500,000
­
<
1.5
million
6
8
10
8
32
Every
60
days
1.5
million
­
<
5
million
8
10
12
10
40
Every
60
days
>
5
million
10
12
14
12
48
Every
60
days
Ground
Water
Systems
<
500
­
­
1
1
2
Every
180
days
500
­
9,999
­
­
1
1
2
Every
90
days
10,000
­
99,999
1
1
2
2
6
Every
90
days
100,000
­
499,999
1
1
3
3
8
Every
90
days
>
500,000
2
2
4
4
12
Every
90
days
1
For
the
purposes
of
this
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.

2
A
dual
sample
set
must
be
collected
at
each
location.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.

3
See
section
8.2
for
requirements
when
the
number
of
entry
points
in
a
system
is
different
from
the
number
of
required
near­
entry
point
sites
in
this
table.

4
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.

5
For
the
purposes
of
this
guidance
manual,
"
surface
water"
systems
are
equivalent
to
"
subpart
H"
systems
and
include
systems
that
provide
GWUDI.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
A­
4
Table
A.
2
Stage
2B
Compliance
Monitoring
Requirements
for
Population­
based
Approach
System
Size
(
Population
Served)
Number
of
Distribution
System
Sites2
(
by
location
type)
per
System
Total
Number
of
Sites
per
System
Monitoring
Frequency3
Existing
Stage
1
Compliance
Sites
Highest
TTHM
Highest
HAA5
Surface
Water
Systems4
<
500
­
1
1
25
Every
365
days
500
­
4,999
­
1
1
25
Every
90
days
5,000
­
9,999
­
1
1
2
Every
90
days
10,000
­
24,999
1
2
1
4
Every
90
days
25,000
­
49,999
1
3
2
6
Every
90
days
50,000
­
99,999
2
4
2
8
Every
90
days
100,000
­
499,999
3
6
3
12
Every
90
days
500,000
­
1,499,999
4
8
4
16
Every
90
days
1.5
million
­
<
5
million
5
10
5
20
Every
90
days
>
5
million
6
12
6
24
Every
90
days
Ground
Water
Systems
<
500
­
1
1
25
Every
365
days
500
­
9,999
­
1
1
2
Every
365
days
10,000
­
99,999
1
2
1
4
Every
90
days
100,000
­
499,999
1
3
2
6
Every
90
days
>
500,000
2
4
2
8
Every
90
days
1
For
the
purposes
of
this
manual,
100
percent
purchasing
systems
are
those
systems
that
buy
or
otherwise
receive
all
of
their
finished
water
from
one
or
more
wholesale
systems
year­
round.

2
A
dual
sample
set
must
be
collected
at
each
location,
unless
otherwise
noted.
A
dual
sample
set
is
one
TTHM
and
one
HAA5
sample
that
is
taken
at
the
same
time
and
location.

3
Monitoring
frequency
is
the
approximate
number
of
days
between
monitoring
events.

4
For
the
purposes
of
this
guidance
manual,
"
surface
water"
systems
are
equivalent
to
"
subpart
H"
systems
and
include
systems
that
provide
GWUDI.

5
Dual
sample
sets
are
not
required
at
both
the
high
TTHM
and
the
high
HAA5
site
 
if
the
highest
TTHM
and
HAA5
levels
occur
at
a
different
locations,
then
only
one
sample
is
collected
at
each
location.
If
they
occur
at
the
same
location,
then
a
dual
sample
set
is
collected
at
that
location.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
A­
5
A.
3
Revised
Guidance
Manual
Organization
The
IDSE
and
Stage
2B
requirements
are
less
complex
with
a
monitoring
scheme
that
is
based
only
on
population
served
and
source
water
type
(
the
population­
based
approach)
compared
to
plantbased
requirements.
Table
A.
3
hypothesizes
how
this
manual
might
be
revised
if
the
monitoring
requirements
were
to
change.
Note
two
chapters
will
be
deleted
and
no
additional
chapters
will
be
necessary.

Table
A.
3
Revised
Chapter
Organization
and
Content
Reflecting
a
Population­
Based
Monitoring
Approach
for
All
Systems
Current
Chapter
Chapter
Revisions
1
­
Introduction
Revised.
(
Remove
distinctions
between
producing
and
100
percent
purchasing
system).

2
­
Criteria
for
IDSE
Waiver
and
Reporting
Requirements
Same
3
­
System
Specific
Study
Same
4
­
SMP
Requirements
for
100
Percent
Purchasing
Systems
Revised
to
present
SMP
requirements
for
all
systems,
SW
and
GW.

5
­
SMP
Requirements
for
Producing
Systems,
SW
serving
>
10,000
people
Deleted.
Revised
Chapter
4
will
cover
all
systems.

6
­
SMP
Requirements
for
Producing
Systems,
SW
serving
500
­
9,999
people
and
GW
serving
>
10,000
people
Deleted.
Revised
Chapter
4
will
cover
all
systems.

7
­
SMP
Requirements
for
Producing
Systems,
SW
serving
<
500
people
and
GW
serving
<
10,000
people
Revised
to
address
only
systems
serving
less
than
500
people.
Becomes
Chapter
5.

8
­
SMP
Site
Selection
and
Reporting
Same,
becomes
Chapter
6.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
A­
6
References
EPA,
2000.
Stage
2
M­
DBP
Agreement
in
Principle.
Microbial/
Disinfection
Byproducts
(
M­
DBP)
Federal
Advisory
Committee.
September
12,
2000.
Appendix
B
Factors
Affecting
Disinfection
Byproduct
Formation
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
B­
1
B.
1
Introduction
The
purpose
of
this
appendix
is
to
identify
and
discuss
the
factors
that
affect
formation
of
disinfection
byproducts
(
DBPs)
in
water
treatment
processes
and
distribution
systems.
This
appendix
is
intended
to
serve
as
a
tool
for
systems
for
the
purpose
of
identifying
IDSE
sample
locations
and
Stage
2B
monitoring
locations.
It
is
divided
into
the
following
sections:

B.
2
Factors
Affecting
DBP
Formation
B.
3
Disinfectant
Type
B.
4
Disinfectant
Dose
B.
5
Time
Dependency
of
DBP
Formation
B.
6
Concentration
and
Characteristics
of
DBP
Precursors
B.
7
Water
Temperature
B.
8
Water
pH
B.
2
Factors
Affecting
DBP
Formation
Organic
DBPs
(
and
oxidation
byproducts)
are
formed
by
the
reaction
between
organic
substances
and
oxidizing
agents
(
e.
g.,
chlorine
and
ozone)
that
are
added
to
water
during
treatment.
In
most
water
sources,
natural
organic
matter
(
NOM)
is
the
most
significant
constituent
of
organic
substances
and
DBP
precursors.
NOM
is
often
measured
as
total
organic
carbon
(
TOC)
and
as
such
the
two
terms
are
used
interchangeably
in
much
of
the
discussion
presented
in
this
appendix.
Major
factors
affecting
the
type
and
amount
of
DBPs
formed
include:

°
Type
of
disinfectant,
dose,
and
residual
concentration
°
Contact
time
and
mixing
conditions
between
disinfectant
(
oxidant)
and
precursors
°
Concentration
and
characteristics
of
precursors
°
Water
temperature
°
Water
chemistry
(
including
pH,
bromide
ion
concentration,
organic
nitrogen
concentration,
and
presence
of
other
reducing
agents
such
as
iron
and
manganese)

B.
3
Disinfectant
Type
Organic
DBPs
can
be
subdivided
into
halogenated
and
non­
halogenated
byproducts.
Halogenated
organic
disinfection
byproducts
are
formed
when
organic
compounds
found
in
water
react
with
free
chlorine,
free
bromine,
or
free
iodine.
The
formation
reactions
take
place
in
both
the
treatment
plant
and
the
distribution
system.
Free
chlorine
can
be
introduced
to
water
directly
as
a
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
B­
2
primary
or
secondary
disinfectant,
as
a
byproduct
of
the
manufacturing
of
chlorine
dioxide,
or
as
a
component
in
the
formation
of
chloramines
for
secondary
disinfection.
Reactions
between
NOM
and
chlorine
lead
to
the
formation
of
a
variety
of
halogenated
DBPs
including
THMs
and
HAAs.

Free
chlorine
and
ozone
oxidize
bromide
ion
to
hypobromite
ion/
hypobromous
acid,
which
in
turn
can
react
with
NOM
to
form
brominated
DBPs
(
e.
g.,
bromoform).
The
presence
of
bromide
affects
both
the
rate
and
yield
of
DBPs.
As
the
ratio
of
bromide
to
NOM
(
measured
as
total
organic
carbon)
increases,
the
percentage
of
brominated
DBPs
increases.
For
example,
Krasner
(
1999)
reported
the
rate
of
THM
formation
is
higher
in
waters
with
increased
concentrations
of
bromide.
Oxidation
of
organic
nitrogen
can
lead
to
the
formation
of
DBPs
containing
nitrogen,
such
as
haloacetonitriles,
halopicrins,
and
cyanogen
halide
(
Reckhow
et
al.
1990;
Hoigné
and
Bader
1988).
Brominated
DBPs
can
also
form
by
bromine
substitution
in
the
chlorinated
byproducts.
Hypobromous
acid
is
a
more
effective
substituting
agent,
while
hypochlorous
acid
is
a
better
oxidant
(
Krasner
1999).

Non­
halogenated
DBPs
may
form
when
precursors
react
with
strong
oxidants.
For
example,
the
reaction
of
organics
with
ozone
and
hydrogen
peroxide
results
in
the
formation
of
aldehydes,
aldoand
keto­
acids,
and
organic
acids
(
Singer
1999).
Chlorine
can
also
trigger
the
formation
of
some
nonhalogenated
DBPs
(
Singer
and
Harrington
1993).
Many
of
the
non­
halogenated
DBPs
are
biodegradable.

Studies
have
documented
that
chloramines
produce
significantly
lower
DBP
levels
than
free
chlorine,
and
there
is
no
clear
evidence
that
the
reaction
of
NOM
and
chloramine
leads
to
the
formation
of
THMs
(
Singer
and
Reckhow
1999;
EPA
1999).
Predictions
of
an
empirical
DBP
formation
model
calibrated
using
ICR
data
indicated
that
THMs
and
HAAs
are
formed
in
full­
scale
plants
and
distribution
systems
under
chloraminated
conditions
at
a
fraction
of
the
amount
that
would
be
expected
based
on
observations
of
DBP
formation
under
free
chlorine
conditions.
The
amount
of
formation
with
chloramines
varied
from
5
percent
to
35
percent
of
that
calculated
for
free
chlorine,
depending
on
the
individual
DBP
species
(
Swanson
et
al.
2001).

It
is
possible
that
DBPs
might
form
during
the
mixing
of
chlorine
and
ammonia,
when
free
chlorine
might
react
with
NOM
before
the
complete
formation
of
chloramines.
In
addition,
monochloramine
slowly
hydrolyzes
to
release
free
chlorine
in
water.
This
free
chlorine
may
contribute
to
the
formation
of
small
amounts
of
additional
DBPs
in
the
distribution
system.
The
benefits
of
low
DBP
formation
with
chloramines
are
especially
important
at
the
extremities
of
the
distribution
system
where
high
DBP
levels
can
found.

The
application
of
chlorine
dioxide
does
not
produce
significant
amounts
of
organic
halogenated
DBPs.
Only
small
amounts
of
total
organic
halides
(
TOXs,
the
class
of
halogenated
organic
byproducts
that
includes
THMs
and
HAAs)
are
formed.
However,
THMs
and
HAAs
will
form
if
excess
chlorine
is
added
to
water
to
ensure
complete
reaction
with
sodium
chlorite
during
the
production
of
chlorine
dioxide.

To
date,
there
is
no
evidence
to
suggest
that
ultraviolet
irradiation
(
UV)
results
in
the
formation
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
B­
3
of
any
disinfection
byproducts;
however,
little
research
has
been
performed
in
this
area.
Most
of
the
research
regarding
application
of
UV
and
DBP
formation
has
focused
on
chlorinated
DBP
formation
as
a
result
of
UV
application
prior
to
the
addition
of
chlorine
or
chloramines.
The
evidence
suggests
UV
does
not
affect
chlorinated
DBP
formation.

Ozone
does
not
produce
chlorinated
DBPs;
however,
ozone
can
alter
the
reactions
between
chlorine
and
NOM
and
affect
the
speciation
of
chlorinated
DBPs
when
chlorine
is
added
downstream.
In
waters
with
sufficient
bromide
concentrations,
ozonation
can
lead
to
the
formation
of
bromate
and
other
brominated
DBPs.
Bromate,
like
THMs
and
HAAs,
is
a
regulated
DBP.
Ozonation
of
natural
waters
also
produces
aldehydes,
haloketones,
ketoacids,
carboxylic
acids,
and
other
types
of
biodegradable
organic
material.
The
biodegradable
fraction
of
organic
material
can
serve
as
a
nutrient
source
for
microorganisms,
and
should
be
removed
to
prevent
microbial
regrowth
in
the
distribution
system.

B.
4
Disinfectant
Dose
The
concentration
of
disinfectant
can
affect
the
formation
of
DBPs.
In
general,
changes
in
the
disinfectant
dose
have
a
great
impact
on
DBP
formation
during
primary
disinfection.
This
is
because
the
amount
of
disinfectant
added
during
primary
disinfection
is
usually
less
than
the
long­
term
demand
and
the
disinfectant
is
the
limiting
reactant
in
DBP
formation
reactions.
Although
disinfectant
dose
can
affect
DBP
formation
during
secondary
disinfection,
the
effect
is
less
significant
than
in
primary
disinfection.
During
secondary
disinfection
DBP
formation
reactions
may
be
precursor
limited
since
an
excess
of
disinfectant
is
added
to
the
water.
In
the
distribution
system,
DBP
formation
reactions
become
disinfectant­
limited
when
the
free
chlorine
residual
drops
to
low
levels.
Singer
and
Reckhow
(
1999)
suggested
a
chlorine
concentration
of
0.3
mg/
L
as
a
rule
of
thumb.

In
many
systems
booster
disinfection
is
applied
to
raise
disinfectant
residual
concentration,
especially
in
remote
areas
of
the
distribution
system
or
near
storage
tanks
where
water
age
may
be
high
and
disinfectant
residuals
can
be
low.
The
additional
chlorine
dose
applied
to
the
water
at
these
booster
facilities
can
increase
THM
and
HAA
levels
when
sufficient
precursors
remain
in
the
water.
Booster
chlorination
can
also
maintain
high
HAA
concentrations
because
the
increased
free
chlorine
residual
can
prevent
the
biodegradation
of
HAAs.

B.
5
Time
Dependency
of
DBP
Formation
In
general,
DBPs
continue
to
form
in
drinking
water
as
long
as
disinfectant
residuals
and
reactive
DBP
precursors
are
present.
Therefore,
the
longer
the
contact
time
between
the
disinfectant/
oxidant
and
NOM,
the
greater
the
amount
of
DBPs
that
can
be
formed.
This
accumulation
is
a
consequence
of
the
formation
of
THMs
and
HAAs
and
their
associated
chemical
stabilities,
which
are
generally
quite
high
in
the
disinfected
drinking
water
as
long
as
a
significant
disinfectant
residual
is
still
present
(
Singer
and
Reckhow
1999).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
B­
4
High
TTHM
values
usually
occur
where
the
water
age
is
the
oldest.
Unlike
THMs,
HAAs
cannot
be
consistently
related
to
water
age
because
HAAs
are
known
to
biodegrade
over
time
when
the
disinfectant
residual
is
low.
This
might
result
in
relatively
low
HAA
concentrations
in
areas
of
the
distribution
system
where
disinfectant
residuals
are
depleted.

In
contrast
to
chlorination
byproducts,
ozonation
byproducts
form
more
rapidly,
but
their
period
of
formation
is
much
lower
than
that
of
chlorination
byproducts(
Singer
and
Reckhow
1999).
This
is
the
result
of
the
quick
dissipation
of
ozone
residuals
in
drinking
water
treatment
plants.

B.
6
Concentration
and
Characteristics
of
DBP
Precursors
The
formation
of
halogenated
DBPs
is
related
to
the
concentration
of
NOM
at
the
point
of
chlorination.
Greater
DBP
levels
are
formed
in
waters
with
high
concentrations
of
precursors.
Studies
conducted
with
different
fractions
of
NOM
have
indicated
the
reaction
between
chlorine
and
NOM
with
high
aromatic
content
tends
to
form
higher
DBP
levels
than
NOM
with
low
aromatic
content.
For
this
reason,
UV
absorbance
(
typically
indicated
by
UV
absorbance
at
254
nm
[
UV­
254]),
which
is
generally
attributed
to
the
aromatic
and
unsaturated
components
of
NOM,
is
considered
a
good
predictor
of
the
tendency
of
a
source
water
to
form
THMs
and
HAAs
(
Owen
et
al.
1998;
Singer
and
Reckhow
1999).
It
should
be
noted,
however,
that
the
more
highly
aromatic
precursors,
characterized
by
high
UV­
254,
in
source
waters
are
more
easily
removed
by
coagulation.
Thus,
it
is
the
UV­
254
measurement
immediately
upstream
of
the
point(
s)
of
chlorination
within
a
treatment
plant
that
is
more
directly
related
to
THM
and
HAA
formation
potential.

B.
7
Water
Temperature
The
rate
of
formation
of
THMs
increases
with
increasing
temperature.
HAA
formation
rates
may
also
increase
with
temperature,
though
the
effects
are
less
pronounced.
Consequentially,
the
highest
THM
and
HAA
levels
may
occur
in
the
warm
summer
months.
However,
water
demands
are
often
higher
in
warmer
months,
resulting
in
lower
water
age
within
the
distribution
system
and
helping
to
control
DBP
formation.
Furthermore,
high
temperature
conditions
in
the
distribution
system
promote
the
accelerated
depletion
of
residual
chlorine,
which
can
mitigate
DBP
formation
and
promote
biodegradation
of
HAAs
(
unless
chlorine
dosages
are
increased
to
maintain
high
residuals).
(
Singer
and
Reckhow
1999).
For
these
reasons,
depending
on
the
specific
system,
the
highest
THM
and
HAA
levels
may
be
observed
during
months
which
are
warm,
but
not
necessarily
the
warmest.

Seasonal
trends
affect
differently
where
high
THM
and
HAA
concentrations
might
be
found.
For
example,
when
water
is
colder,
microbial
activity
is
typically
lower
and
DBP
formation
kinetics
are
slower.
Under
these
conditions,
the
highest
THM
and
HAA
concentrations
might
appear
coincident
with
the
oldest
water
in
the
system.
In
warmer
water,
the
highest
HAA
concentrations
might
appear
in
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
B­
5
fresher
water,
which
is
likely
to
contain
higher
disinfectant
residuals
that
can
prevent
the
biodegradation
of
HAAs.

B.
8
Water
pH
In
the
presence
of
NOM
and
chlorine,
THM
formation
increases
with
increasing
pH,
whereas
the
formation
of
HAAs
and
other
DBPs
increase
with
decreasing
pH.
The
increase
of
THMs
at
higher
pH
values
is
likely
due
to
base
catalyzed
reactions
that
lead
to
THM
formation.
HAA
formation
pathway
can
be
altered
at
high
pH
since
their
precursors
can
hydrolyze
(
Singer
and
Reckhow
1999).

The
major
byproducts
of
ozonation
are
not
affected
by
base
hydrolysis.
However,
the
rate
of
decomposition
of
ozone
to
hydroxyl
radical
is
accelerated
as
pH
increases.
This
occurrence
is
thought
to
be
responsible
for
the
decrease
of
some
byproducts
(
e.
g.,
aldeydes)
and
the
increase
of
others
(
e.
g.,
carbonyl
byproduct
and
total
organic
halides;
Singer
and
Reckhow
1999).
The
application
of
ozone
to
bromide
containing
waters
leads
to
the
formation
of
hypobromite
and
hypobromous
acid.
At
low
pH,
the
equilibrium
shifts
to
hypobromous
acid
which
can
react
with
NOM
to
form
halogenated
byproducts
such
as
bromoform
and
dibromoacetic
acid
(
Singer
and
Reckhow
1999).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
B­
6
References
EPA,
1999.
Alternative
Disinfectants
and
Oxidants
Guidance
Manual.
EPA
815­
R­
99­
014.

Hoigne
J.,
and
H.
Bader.
1988.
"
The
formation
of
Trichloronitromethane
(
chloropicrin)
and
Chloroform
in
a
Combined
Ozonation/
Chlorination
Treatment
of
Drinking
Water."
Water
Resources.
22
(
3):
313.

Krasner
S.
W.,
1999.
"
Chemistry
of
Disinfection
By­
Product
Formation",
in
Formation
and
Control
of
Disinfection
By­
Products
in
Drinking
Water,
Singer
P.
C.
editor,
American
Water
Works
Association,
Denver
CO.

Reckhow,
D.
A.,
P.
C.
Singer,
and
R.
L.
Malcom.
1990.
"
Chlorination
of
Humic
Mateials:
Byproduct
Formation
and
Chemical
Interpretations."
Environ.
Sci.
Technol.
24(
11):
1655.

Singer,
P.
C.
and
D.
A.
Reckhow.
1999.
"
Chemical
Oxidation."
Water
Quality
and
Treatment,
5th
edition.
Letterman
R.
D.
technical
editor,
American
Water
Works
Association,
McGraw­
Hill,
New
York,
NY.

Singer,
P.
C.
(
editor)
1999.
Formation
and
Control
of
Disinfection
Byproducts
in
Drinking
Water.
American
Water
Works
Association,
Denver,
CO.

Singer,
P.
C.,
and
G.
W.
Harrington.
1993.
"
Coagulation
of
DBP
Precursors:
Theoretical
and
Practical
Considerations."
Conference
proceedings,
AWWA
Water
Quality
Technology
Conference,
Miami,
FL.

Swanson,
W.
J.,
Z.
Chowdhury,
R.
Summers,
and
G.
Solarik.
2001.
"
Predicting
DBPs
at
Full­
Scale:
Calibration
and
Validation
of
the
Water
Treatment
Plant
Model
Using
ICR
Data"
Conference
proceedings,
2001
AWWA
Annual
Conference
and
Exhibition,
Washington,
DC.
Appendix
C
TTHM
and
HAA5
Sampling
Protocol
This
page
intentionally
left
blank.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
C­
1
C.
1
Introduction
TTHM
and
HAA5
samples
must
be
properly
collected
and
analyzed
to
ensure
accurate
analytical
results.
For
example,
THMs
are
volatile
chemicals,
meaning
they
can
move
from
the
liquid
phase
to
the
gas
phase
under
ambient
conditions.
Therefore,
care
must
be
taken
to
make
sure
that
no
air
bubbles
are
present
in
the
filled
sample
vial.
This
appendix
summarizes
information
on
proper
sample
collection,
handling,
and
laboratory
analytical
techniques.

C.
2
Analytical
Methods
Table
C.
1
lists
the
analytes
that
are
included
in
TTHM
and
HAA
analyses.

Table
C.
1
TTHM
and
HAA
Analytes
Analyte
Group
Code
Analytes
in
Group
(
Abbreviation
for
Analyte)

HAA5
Haloacetic
acids:
Dibromoacetic
acid
(
DBAA)
Dichloroacetic
acid
(
DCAA)
Monobromoacetic
acid
(
MBAA)
Monochloroacetic
acid
(
MCAA)
Trichloroacetic
acid
(
TCAA)

HAA9
HAA5
plus
four
additional
analytes
Bromochloroacetic
acid
(
BCAA)
Bromodichloroacetic
acid
(
BDCAA)
Chlorodibromoacetic
acid
(
CDBAA)
Tribromoacetic
acid
(
TBAA)

TTHM
Trihalomethanes:
Bromodichloromethane
(
BDCM)
Bromoform
(
CHBr3)
Chloroform
(
CHCl3)
Dibromochloromethane
(
DBCM)

Table
C.
2
lists
the
approved
laboratory
analytical
methods
for
TTHM
and
HAA5
along
with
guidelines
for
sample
collection
and
storage.
These
guidelines
include
type
of
sample
container,
preservative
and
dechlorinating
agents,
pH,
and
sample
collection.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
C­
2
Table
C.
2
Sampling
Requirements
of
TTHM
and
HAA5
Analyses
Analyte
Group
Analytical
Method
Sample
Container
Material2
Preservative/
Dechlorinating
Agent
(
Recommended
amount)
Storage
Guidelines
Sample
Collection
Guidelines
TTHM
EPA
502.2
40
ml
­
120
ml
screw
cap
glass
vials
with
PTFE­
faced
silicone
septum
Options:
(
1)
3
mg
Na2S2O3/
40
mL
sample
or
(
2)
3
mg
Na2S2O3/
40
mL
sample
and
immediate
acidification
using
HCl
to
pH
<
2
or
(
3)
25
mg
ascorbic
acid/
40
mL
sample
and
immediate
acidification
using
HCl
to
pH
<
2.
Option
1
may
be
used
if
THMs
are
the
only
compounds
being
determined
in
the
sample.
Options
2
&
3
require
the
sample
to
be
dechlorinated
prior
to
the
addition
of
acid.
Keep
at
4
°
C.

14
days
maximum
hold
time3.
Fill
bottle
to
just
overflowing
but
do
not
flush
out
preservatives.

No
air
bubbles.

Do
not
overfill.

Seal
sample
vials
with
no
head
space.

If
ascorbic
acid
is
used
to
dechlorinate
TTHM
samples,
then
the
samples
MUST
be
acidified.
Acidification
of
TTHM
samples
containing
Na2S2O3
is
required
if
the
samples
will
also
be
analyzed
for
VOCs.
In
both
cases,
the
pH
must
be
adjusted
at
the
time
of
sample
collection,
not
later
at
the
laboratory.
EPA
524.2
40
ml
­
120
ml
screw
cap
glass
vials
with
Teflon­
faced
silicone
septum
EPA
551.1
60
ml
screw
cap
glass
vials
with
PTFE­
faced
silicone
septum
1
g
phosphate
buffer
&
NH4Cl
or
Na2SO3
mixture
per
60
mL
sample
(
mixture
consists
of
1
part
Na2HPO4,
99
parts
KH2PO4
,
and
0.6
parts
NH4Cl
or
Na2SO3.
1g
per
60
mL
results
in
a
pH
of
4.5­
5.5
and
0.1
mg
NH4Cl
or
Na2SO3
per
mL
of
sample.)

HAA5
EPA
552.1
250
ml
(
approx.)
amber
glass
bottles
fitted
with
Teflonlined
screw
caps
0.1
mg
NH4Cl
per
mL
of
sample
EPA
552.2
50
ml
(
approx.)
amber
glass
bottles
fitted
with
Teflonlined
screw
caps
EPA
552.34
50
ml
(
approx.)
amber
glass
bottles
fitted
with
Teflonlined
screw
caps
SM
6251
B
40
ml
or
60
ml
screw
cap
glass
65
mg
NH4Cl
1
(
40
CFR
141.131
(
b))

2
Selection
of
container
should
be
coordinated
with
the
laboratory.
3
The
holding
time
has
been
changed
to
14
days
for
all
HAA5
samples
as
a
part
of
the
Stage
2
DBPR.
4
EPA
Method
552.3
has
been
added
as
an
approved
HAA5
method
as
part
of
the
Stage
2
DBPR.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
C­
3
C.
2.1
Sampling
Procedure
It
is
important
to
follow
sampling
procedures
provided
by
your
certified
laboratory.
Sampling
procedures
may
vary
slightly
among
individual
laboratories;
you
should
contact
your
laboratory
to
learn
their
procedures.
The
following
is
common
procedure
for
collecting
samples
for
TTHM
and
HAA5
analyses.

You
will
need:

1)
Sample
vials
provided
by
laboratory
(
most
laboratories
will
provide
sample
vials
with
proper
preservative
and
dechlorinating
agents)

2)
Small
bottle
of
1:
1
hydrochloric
acid
and
eye
dropper
or
pasteur
pippettes
(
pH
adjustment
is
necessary
for
some
TTHM
methods)

3)
Water
proof
labels
and
permanent
(
indelible
ink)
marker
4)
Ice/
coolant
and
cooler
Procedure:

1)
Label
each
sample
vial.
Use
waterproof
labels
and
indelible
ink.
Each
label
should
include:

°
Unique
sample
ID
°
System
name
°
Sample
location
°
Sample
date
and
time
°
Analysis
required,
if
not
already
on
label
2)
Remove
the
aerator
from
the
tap,
if
there
is
one
present.

3)
Open
the
water
tap
and
allow
the
system
to
flush
until
the
water
temperature
has
stabilized
(
usually
about
3­
5
minutes).
The
purpose
of
this
step
is
to
ensure
the
sample
does
not
represent
stagnant
water
that
has
sat
for
a
long
time
in
the
water
line
between
the
street
and
the
faucet.
The
sample
should
be
representative
of
the
water
flowing
through
the
distribution
system
at
the
chosen
sampling
point.

4)
Adjust
the
flow
so
that
no
air
bubbles
are
visually
detected
in
the
flowing
stream.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
C­
4
5)
Slowly
fill
the
sample
vial
almost
to
the
top
without
overflowing.
Use
the
bottle
cap
to
add
a
small
amount
of
additional
sample
water
while
simultaneously
capping
the
vial
to
achieve
a
headspace­
free
sample.
Be
careful
not
to
rinse
out
any
of
the
preservative/
dechlorinating
agent
during
this
process.
After
the
bottle
is
filled,
invert
three
or
four
times.

6)
If
collecting
TTHM
samples
that
require
acidification,
let
the
sample
set
for
about
1
minute,
allowing
the
dechlorinating
chemical
to
take
effect.
Carefully
open
the
vial
and
adjust
the
pH
of
TTHM
sample
to
<
2
by
adding
approximately
4
drops
of
hydrochloric
acid
for
every
40
mL
of
sample
(
amount
of
acid
needed
will
depend
on
buffering
capacity
of
sample).
Recap
the
vial,
and
invert
three
or
four
times.

7)
Invert
the
vial
and
tap
it
to
check
for
air
bubbles.
If
bubbles
are
detected,
carefully
open
the
vial
and
add
more
sample
water
using
the
cap
to
achieve
a
headspace­
free
sample.

8)
Immediately
cool
the
samples
to
4oC
by
placing
them
in
a
cooler
with
frozen
refrigerant
packs
or
ice,
or
in
a
refrigerator.
Samples
should
be
maintained
at
this
temperature
during
shipping
to
the
laboratory.

9)
Complete
the
Sample
Chain
of
Custody
provided
by
the
laboratory
and
include
it
with
the
sample
shipment.

C.
2.2
Regarding
Loss
of
Samples
Samples
may
be
"
lost"
due
to
a
number
of
reasons:

°
Bottle
broken
during
shipment
from
the
water
system
to
the
laboratory
°
Sample
improperly
collected
(
e.
g.,
sample
bottle
not
completely
filled)

°
Sample
improperly
shipped
(
e.
g.,
not
kept
cold
during
shipment)

°
Sample
improperly
preserved
(
e.
g.,
not
dechlorinated)

°
Bottle
is
broken
or
lost
at
the
laboratory
°
Quality
control
doesn't
meet
method
specifications
when
sample
is
analyzed
Resampling
for
the
lost
sample
should
be
conducted
as
soon
as
possible
after
the
loss
is
determined.
Only
the
lost
sample
needs
to
be
recollected,
not
the
entire
sample
set
that
was
collected
together.
Make
sure
to
note
the
loss
of
sample
and
resample
date
as
a
deviation
in
your
IDSE
report.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
C­
5
C.
3
Analytical
Method
Descriptions
The
following
are
brief
summaries
of
the
approved
TTHM
and
HAA5
methods.

C.
3.1
EPA
Method
502.2
Highly
volatile
organic
compounds
with
low
water
solubility
are
extracted
(
purged)
from
the
sample
matrix
by
bubbling
an
inert
gas
through
a
5
mL
aqueous
sample.
Purged
sample
components
are
trapped
in
a
tube
containing
suitable
sorbent
materials.
When
purging
is
complete,
the
sorbent
tube
is
heated
and
back
flushed
with
helium
to
thermally
desorb
trapped
sample
components
onto
a
capillary
gas
chromatography
(
GC)
column.
The
column
is
temperature
programmed
to
separate
the
method
analytes
which
are
then
detected
with
a
photoionization
detector
(
PID)
and
an
electrolytic
conductivity
detector
(
ELCD)
placed
in
series.
Analytes
are
quantitated
by
procedural
standard
calibration.
The
PID
is
not
required,
if
only
TTHMs
are
being
determined.

Identifications
are
made
by
comparison
of
the
retention
times
of
unknown
peaks
to
the
retention
times
of
standards
analyzed
under
the
same
conditions
used
for
samples.
Additional
confirmatory
information
can
be
gained
by
comparing
the
relative
response
from
the
two
detectors.
For
absolute
confirmation,
a
gas
chromatography/
mass
spectrometry
(
GC/
MS)
determination
according
to
USEPA
Method
524.2.

Highly
volatile
compounds
with
low
water
solubility,
including
TTHMs,
are
extracted
from
the
water
sample
by
bubbling
an
inert
gas
through
5
mL
of
the
sample.
The
chemical
compounds
that
are
extracted
from
the
water
sample
are
then
trapped
in
a
tube
that
contains
material
to
which
the
chemicals
attach,
or
sorb.
Once
the
extraction
process
has
been
completed,
the
tube
containing
the
extracted
chemicals
is
treated
with
helium,
and
the
mixture
of
helium
and
chemicals
enters
a
capillary
gas
chromatography
(
GC)
column.
The
column
is
temperature
programmed
to
separate
the
chemicals
extracted
from
the
water,
which
are
then
detected
with
a
photoionization
detector
(
PID)
and
an
electrolytic
conductivity
detector
(
ELCD)
placed
in
series.
The
amount
of
each
chemical
is
determined
using
procedural
standard
calibration.
The
PID
is
not
required
if
only
TTHMs
are
being
measured.

Chemical
compounds
are
identified
by
comparing
the
retention
times
of
unknown
GC
peaks
with
retention
times
for
chemical
standards
analyzed
under
the
same
conditions.
Confirmation
can
be
made
by
comparing
the
relative
response
from
the
two
detectors.
For
absolute
confirmation
of
results,
a
gas
chromatography/
mass
spectrometry
(
GC/
MS)
determination
can
be
made
using
U.
S.
EPA
Method
524.2.

For
a
complete
description
of
this
method
see
EPA
publication:
EPA/
600/
R­
95/
131
Methods
for
the
Determination
of
Organic
Compounds
in
Drinking
Water:
Supplement
III.
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
C­
6
C.
3.2
EPA
Method
524.2
Volatile
organic
compounds,
including
TTHMs,
are
extracted
from
the
water
sample
by
bubbling
an
inert
gas
through
the
sample.
Extracted
compounds
are
trapped
in
a
tube
that
contains
material
to
which
the
chemicals
attach,
or
sorb.
When
the
extraction
process
is
complete,
the
tube
is
heated
and
flushed
with
helium
to
de­
sorb
the
trapped
chemicals
into
a
capillary
gas
chromatography
(
GC)
column
interfaced
with
a
mass
spectrometer
(
MS).
The
GC
column
is
temperature
programmed
to
allow
for
the
separation
of
different
chemicals,
which
are
then
detected
with
the
MS.
Compounds
detected
by
the
GC
are
identified
by
comparing
their
measured
mass
spectra
and
retention
times
with
reference
mass
spectra
and
retention
times
in
a
database.
Reference
mass
spectra
and
retention
times
for
different
compounds
are
obtained
by
measuring
calibration
standards
under
the
same
conditions
that
are
used
for
the
water
samples.
The
concentration
of
each
compound
is
measured
by
comparing
the
MS
response
of
the
compound
with
the
MS
response
of
another
compound
used
as
an
internal
standard.
Surrogate
chemicals,
whose
concentrations
are
known
in
every
sample,
are
measured
using
the
same
internal
standard
calibration
procedure.

For
a
complete
description
of
this
method
see
EPA
publication:
EPA/
600/
R­
95/
131
Methods
for
the
Determination
of
Organic
Compounds
in
Drinking
Water:
Supplement
III.

C.
3.3
EPA
Method
551.1
A
50
mL
volume
of
the
sample
is
extracted
using
either
3
mL
of
methyl­
tert­
butyl
ether
(
MTBE)
or
5
mL
of
pentane.
A
small
sub­
sample
of
the
extract
(
2
µ
L)
is
then
injected
into
a
GC
equipped
with
a
fused
silica
column
for
separation,
and
a
linearized
electron
capture
detector
for
analysis.
Concentrations
of
different
chemical
compounds
are
determined
by
comparing
their
measured
amounts
to
standard
calibration
curves.

A
typical
sample
can
be
extracted
and
analyzed
using
this
method
in
50
minutes
for
chlorinated
byproducts
(
e.
g.,
HAA5)
and
chlorinated
solvents,
and
in
two
hours
for
all
of
the
compounds
analyzed
by
this
method.
Results
can
be
confirmed
by
using
a
second,
different
GC
column,
by
using
primary
confirmation
columns
installed
in
a
single
injection
port,
or
by
a
separate
confirmation
analysis.

For
a
complete
description
of
this
method
see
EPA
publication:
EPA/
600/
R­
95/
131
Methods
for
the
Determination
of
Organic
Compounds
in
Drinking
Water:
Supplement
III.

C.
3.4
EPA
Method
552.1
A
100
mL
volume
of
the
sample
is
adjusted
to
pH
5.0
and
extracted
using
a
pre­
conditioned
miniature
anion
exchange
column.
The
chemical
compounds
to
be
analyzed
are
first
eluted
using
small
amounts
of
acidic
methanol,
and
are
then
esterified
directly
in
this
medium
after
adding
a
small
volume
The
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
C­
7
of
methyl­
tert­
butyl
ether
(
MTBE)
as
a
co­
solvent.
The
methyl
esters
are
partitioned
into
the
MTBE
phase,
and
are
identified
and
measured
using
capillary
column
gas
chromatography
with
an
electron
capture
detector
(
GC/
ECD).

For
a
complete
description
of
this
method
see
EPA
publication:
EPA/
600/
R­
92/
129
Methods
for
the
Determination
of
Organic
Compounds
in
Drinking
Water:
Supplement
II.

C.
3.5
EPA
Method
552.2
The
pH
of
a
40
mL
volume
of
sample
is
adjusted
to
less
than
0.5,
and
the
sample
is
extracted
using
4
mL
of
methyl­
tert­
butyl
ether
(
MTBE).
The
haloacetic
acids
that
have
been
partitioned
are
then
converted
to
their
methyl
esters
by
adding
acidic
methanol
and
heating
them
slightly.
The
acidic
extract
is
then
returned
to
neutral
pH
using
a
saturated
solution
of
sodium
bicarbonate.
The
chemical
compounds
of
interest
are
identified
and
measured
using
capillary
column
gas
chromatography
with
an
electron
capture
detector
(
GC/
ECD).
Chemical
concentrations
are
determined
using
standard
calibration
procedures.

For
a
complete
description
of
this
method
see
EPA
publication:
EPA/
600/
R­
95/
131
Methods
for
the
Determination
of
Organic
Compounds
in
Drinking
Water:
Supplement
III.

C.
3.6
EPA
Method
552.3
[
to
be
developed]

C.
3.7
Standard
Method
6251
B
The
sample
is
extracted
using
methyl­
tert­
butyl
ether
(
MTBE)
at
an
acidic
pH.
A
salting
agent
is
added
during
the
extraction
process
to
increase
the
extraction's
efficiency.
Once
extracted,
compounds
are
methylated
using
diazomethane
solution
to
produce
methyl
ester
or
other
ether
derivatives
that
can
be
separated
in
a
gas
chromatograph.
A
gas
chromatograph
equipped
with
a
fused
silica
capillary
column
and
an
electron
capture
detector
(
GC/
ECD)
is
used
for
analysis.
Alternative
detectors
can
be
used
if
quality
control
criteria
are
met.
Calibration
standards
are
extracted,
methylated,
and
analyzed
in
the
same
manner
as
the
water
samples
to
compensate
for
less
than
100%
recoveries
during
sample
preparation.

For
a
complete
description
of
this
method
see
Standard
Methods
for
the
Examination
of
Water
and
Wastewater:
21st
Edition
published
jointly
by
the
APHA,
AWWA,
and
WEF.
Appendix
D
Simulated
Distribution
System
Test
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
D­
1
D.
1
Introduction
An
SDS
test
involves
storing
a
sample
of
disinfected
finished
water
in
a
manner
that
reflects
the
conditions
(
pH,
temperature,
and
residence
time)
of
the
distribution
system.
The
purpose
of
an
SDS
test
is
to
evaluate
the
potential
of
the
finished
water
to
form
TTHM
and
HAA5
in
the
distribution
system
conditions
at
different
residence
times.
An
SDS
test
is
site­
specific
and
therefore,
there
is
no
universal
set
of
conditions
that
applies
to
all
systems.

Section
D.
2
provides
the
recommended
procedure
for
conducting
an
SDS
laboratory
test.
Section
D.
3
describes
how
SDS
tests
can
be
used
in
conjunction
with
Stage
1
DBPR
and
other
DBP
monitoring
data
to
estimate
average
and
maximum
residence
times.

D.
2
Recommended
SDS
Test
Procedure
A
separate
SDS
sample
should
be
collected
for
each
distribution
system
residence
time
to
be
evaluated.
The
following
protocol
is
recommended
for
collecting,
storing,
and
analyzing
an
SDS
sample:

Test
Conditions
°
The
pH
of
the
sample
should
be
that
of
the
distribution
system
water
(
±
0.2).
No
pH
adjustments
should
be
made
after
collecting
the
finished
water
samples
for
any
of
the
SDS
tests.

°
The
sample
should
be
held
at
a
temperature
comparable
to
the
distribution
system
temperature
between
the
treatment
plant
and
the
TTHM
sampling
points
in
the
distribution
system
for
the
corresponding
time
period.
The
goal
should
be
a
temperature
within
±
2
°
C
of
either
the
water
entering
the
distribution
system
or
the
water
at
the
DBP
sampling
point
being
evaluated.
If
major
temperature
fluctuations
occur
in
the
distribution
system
during
the
SDS
tests,
these
should
be
taken
into
account
when
analyzing
the
data.

°
The
holding
time
of
an
SDS
test
begins
when
an
SDS
sample
is
collected,
and
ends
when
the
sample
is
transferred
into
sample
bottles
(
with
appropriate
preserving
and
dechlorinating
agents)
for
TTHM
and
HAA5
analysis.
The
total
reaction
time
actually
begins
with
the
addition
of
chlorine­
based
oxidants
at
the
treatment
plant.

°
A
disinfectant
residual
should
be
present
at
the
end
of
the
holding
time.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
D­
2
Sample
Collection
°
SDS
samples
should
be
collected
at
the
entry
point
to
the
distribution
system,
after
the
final
addition
of
chlorine
and/
or
ammonia
or
any
chemicals
added
for
corrosion
control
or
pH
adjustment
are
completely
mixed
in
treated
water.
(
In
cases
where
systems
use
chloramines
for
secondary
disinfection,
SDS
sample
collection
will
typically
be
at
the
location
where
the
system
measures
free
ammonia
to
control
the
dosing
of
ammonia).
If
systems
employ
booster
disinfection,
then
a
second
SDS
sample
collected
after
booster
disinfectant
addition
and
a
separate
SDS
analysis
are
recommended.

°
SDS
samples
should
be
collected
in
250
mL
amber
glass
bottles
(
or
larger)
with
TFE­
lined
screw
caps,
and
should
be
collected
head
space­
free,
with
no
addition
of
any
preservatives
or
dechlorinating
agents.
(
The
sample
should
be
of
sufficient
volume
for
all
the
analyses
needed
for
SDS
sample
analyses,
i.
e.,
DBPs,
disinfectant
residual,
pH,
etc.)
Prior
to
collecting
the
samples,
the
bottles
should
be
pre­
treated
with
concentrated
chlorine
solution
and
copiously
rinsed
with
deionized
water,
then
oven
dried
at
180
/
C
for
an
hour,
to
ensure
that
the
glassware
is
chlorine
demand
free.

Holding
Time
The
holding
time
represents
a
residence
time
pre­
determined
by
the
system.
The
system
could
conduct
several
SDS
tests
at
a
range
of
residence
times
to
develop
a
kinetic
curve
(
see
section
D.
3).
The
system
could
also
use
estimated
residence
times
of
DBP
sampling
sites
in
the
distribution
system
and
compare
the
SDS
results
to
its
DBP
results.

Sample
Storage
The
bottle
containing
an
SDS
sample
is
best
stored
in
the
treatment
plant
where
it
is
collected.

°
It
can
be
suspended
in
the
plant
clearwell
to
maintain
it
at
the
finished
water
temperature,
or
in
a
container
in
a
sink
with
a
constant
flow
of
finished
or
distributed
water
running
through
the
container.

°
The
collected
sample
may
be
transported
to
an
off­
site
laboratory,
provided
it
is
maintained
at
the
desired
storage
temperature
during
transport
and
for
the
duration
of
the
test.
During
the
holding
time
at
the
laboratory,
an
SDS
sample
can
be
placed
in
an
incubator
(
set
at
the
selected
distribution
system
temperature
±
2
/
C)
or
in
a
container
in
a
sink
with
a
constant
flow
of
finished
or
distributed
water
running
through
the
container
(
if
the
laboratory
receives
water
from
the
same
distribution
system
being
tested).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
D­
3
Sample
Analysis
At
the
end
of
a
specified
residence
time,
an
SDS
sample
is
analyzed
for
several
parameters
(
disinfectant
residual,
TTHM,
and
HAA5,
pH,
temperature).

°
The
SDS
sample
should
be
divided
by
pouring
it
into
sample
bottles
containing
the
appropriate
dechlorinating
agents/
preservatives
for
each
analysis.
The
TTHM
sample
bottle
should
be
filled
first,
followed
by
the
HAA5
sample
bottle.
Care
must
be
taken
to
not
aerate
the
sample
during
this
splitting
process,
in
order
to
prevent
the
loss
of
volatile
THMs.

°
Immediately
after
the
TTHM
and
HAA5
sample
bottles
are
filled,
the
pH,
temperature,
and
disinfectant
residual
concentration
should
be
determined
in
the
remaining
aliquot
of
the
SDS
sample.
If
no
disinfectant
residual
is
detected,
then
the
result
of
this
SDS
test
should
be
thrown
out.

°
The
TTHM
and
HAA5
samples
should
be
analyzed
within
the
holding
time
specified
by
the
method.

°
The
TTHM
and
HAA5
analyses
should
be
conducted
by
a
laboratory
certified
under
the
drinking
water
certification
program
to
perform
those
analyses.
Appendix
C
describes
TTHM
and
HAA5
laboratory
analyses.

D.
3
Using
SDS
Tests
to
Determine
Average
and
Maximum
Residence
Time
For
systems
that
do
not
have
good
information
about
their
residence
time,
a
number
of
SDS
tests
can
be
conducted
and
compared
to
Stage
1
compliance
monitoring
data
to
help
estimate
average
and
maximum
residence
time.
It
should
be
noted
that
the
SDS
tests
should
be
conducted
in
conjunction
(
preferably
done
on
the
same
day
or
a
couple
of
days
before)
with
the
Stage
1
DBP
compliance
monitoring
sampling.

Because
DBP
formation
is
not
linear,
it
is
recommended
that
a
kinetic
curve
be
developed
to
describe
the
system
specific
DBP
formation.
To
create
a
useful
curve,
a
minimum
of
four
SDS
samples
should
be
collected
at
the
finished
water
sampling
location.
Analysis
should
begin
immediately
for
the
first
sample
(
aliquots
should
be
transferred
to
sample
vials
with
appropriate
preservation
and
dechlorinating
agents
for
TTHM
and
HAA5
anlaysis,
and
chlorine
residual,
pH,
and
temperature
should
be
analyzed
immediately
thereafter).
This
represents
time
zero.
A
second
sample
should
be
stored
at
the
finished
or
distribution
system
temperature
(
see
section
D.
2
for
details)
for
an
estimated
maximum
distribution
system
residence
time
(
this
selected
time
interval
will
be
a
best
guess
estimate).
The
other
two
SDS
samples
are
stored
for
two
intermediate
time
intervals
that
equally
subdivide
the
maximum
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
D­
4
0
10
20
30
40
50
60
70
80
0
1
2
3
4
5
6
7
8
9
10
Residence
Time
(
days)
DBP
Concentration
(
ug/
L)

0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
Free
Chlorine
Residual
(

mg/

L)

TTHM
HAA5
Chlorine
residence
time
(
e.
g.,
if
you
estimate
that
your
maximum
residence
time
is
6
days,
store
your
other
two
SDS
samples
for
2
days
and
4
days).
At
the
end
of
the
selected
storage
times,
transfer
the
sample
aliquots
to
appropriate
TTHM
and
HAA5
sample
bottles
(
with
preservation
and
dechlorinating
agents)
for
analysis.
Plot
the
the
resultant
TTHM
and
HAA5
data
(
:
g/
L)
on
the
y­
axis
and
corresponding
holding
times
(
days)
on
the
x­
axis.
An
example
kinetic
curve
with
disinfectant
residual
data
is
presented
in
Figure
D.
1.

Figure
D.
1
SDS
Test
Kinetic
Curve
To
estimate
the
residence
time
of
monitoring
sites
in
the
distribution
system,
use
the
DBP
results
from
the
monitoring
sites
and
the
kinetic
curve
developed
from
the
SDS
tests.
For
example,
the
TTHM
result
from
a
Stage
1
compliance
monitoring
sample
was
40
µ
g/
L.
Using
Figure
D.
1,
40
µ
g/
L
of
TTHM
corresponds
to
a
residence
time
of
2
days.
Combining
these
data
with
disinfectant
residual
data
from
each
of
the
four
SDS
samples
may
also
be
useful.

When
designing
SDS
studies,
systems
using
booster
disinfection
must
consider
the
application
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
D­
5
of
disinfectants
in
the
distribution
system.
For
systems
that
employ
booster
chlorination
in
the
distribution
system,
another
SDS
sample
should
be
taken
after
the
re­
chlorination
station
and
the
residence
time
should
simulate
the
distribution
system
conditions
downstream
of
the
re­
chlorination
station.
Appendix
E
IDSE
SMP
Report
for
Producing
Surface
Water
Systems
Serving
$
10,000
People
This
appendix
is
provided
as
an
example
IDSE
report
for
producing
surface
water
systems
serving
at
least
10,000
people
and
opting
to
complete
the
Standard
Monitoring
Program
(
SMP).

Chapter
5
presents
the
detailed
SMP
requirements
for
these
systems,
and
Chapter
8
provides
guidance
on
selecting
SMP
sites
and
Stage
2B
compliance
monitoring
sites
based
on
SMP
results.
Chapter
8
also
presents
the
IDSE
reporting
requirements.
The
application
of
the
basic
guidance
on
SMP
site
selection
and
Stage
2B
compliance
monitoring
site
selection
is
shown
in
this
example,
along
with
several
instances
of
the
use
of
best
professional
judgement
being
applied.

The
italicized
text
within
the
appendix
consists
of
comments
and
explanations
and
is
not
intended
to
represent
the
recommended
content
of
an
actual
IDSE
Report.
This
page
intentionally
left
blank.
Initial
Distribution
System
Evaluation
Report
for
Elm
City
PWSID
Number:
US1111111
Address:
1234
Main
Street
Elm
City,
US
99999
Contact
Person:
Mr.
Ronald
Doe,
P.
E.

Phone
Number:
123­
555­
0000
Fax
Number:
123­
555­
0001
Email
Address:
Rdoe@
ci.
elmcity.
us
System
Type:
Community,
surface
water
Population
Served:
160,000
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
1
I.
SMP
PLAN
1.
System
Description:

This
section
of
the
report
should
include
a
summary
of
typical
system
operating
characteristics
(
and
how
they
change
on
a
seasonal
basis
if
appropriate)
explaining
how
sources
are
used
to
meet
system
demands,
where
high
water
age
is
expected
to
occur,
and
any
special
aspects
of
operation
that
could
affect
DBP
concentrations
in
the
distribution
system.
Information
about
water
treatment
processes
and
source
water
quality
data
should
also
be
in
this
section,
including
a
brief
description
of
the
water
treatment
process
train.

General
system
characteristics:
Service
area:
Elm
City
plus
surrounding
suburban
areas
Production:
Annual
average
daily
production
=
15
MGD
Source
Water
Information:
Hardwood
Lake
(
surface
water)
pH:
from
6.9
to
7.5
Alkalinity:
from
82
to
98
mg/
L
as
CaCO3
TOC:
from
2.1
to
4.0
mg/
L
as
C
Softwood
River
(
surface
water)
pH:
from
6.8
to
7.9
Alkalinity:
from
77
to
94
mg/
L
as
CaCO3
TOC:
from
1.6
to
4.4
mg/
L
as
C
Entry
points
and
service
areas
under
the
influence
of
each
entry
point:
(
Entry
points
should
be
tied
to
source(
s)
and
typical
flows
noted)

Entry
points:
Hardwood
Plant:
Design
Capacity
=
20
mgd
Average
Daily
Production
=
7.5
mgd
Softwood
River
Plant:
Design
Capacity
=
20
mgd
Average
Daily
Production
=
7.5
mgd
Customers
located
in
the
Industrial
Park
area,
Oakville,
Pineville,
and
south
downtown
areas
generally
receive
water
from
the
Hardwood
Plant
Customers
located
in
the
Cypressville,
Cedarville,
Poplarville,
and
north
downtown
areas
generally
receive
water
from
the
Softwood
Plant
Customers
located
in
the
Weeping
Willow
Community,
Appleville,
and
central
downtown
areas
generally
receive
a
mixture
of
water
from
both
plants
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
2
Treatment
Provided:
Hardwood
 
ferric
chloride
coagulation,
flocculation,
sedimentation,
dual­
media
filtration
Softwood
River
 
ferric
chloride
coagulation,
flocculation,
sedimentation,
dual­
media
filtration,
followed
by
GAC
Primary
and
residual
disinfection:
Chlorine/
chlorine
at
both
plants
Description
of
distribution
system:
Distribution
system
(
estimated
length
of
lines
and
range
of
diameter):
About
400
miles,
4"
­
56"
(
approximately
6
MG
total
pipe
volume)

5
storage
tanks
of
10
MG
total
capacity
1
ground
tank
4
MG
capacity
4
elevated
tanks
6
MG
capacity
Following
recent
customer
complaints
in
areas
downstream
of
the
Cherry
Hill
tank,
the
city
evaluated
mixing
conditions
in
each
distribution
system
tank.
As
a
result,
the
city
made
some
inlet/
outlet
modifications
at
both
the
Cherry
Hill
and
Apple
Drive
tanks
to
improve
tank
mixing.

The
average
residence
time
of
water
in
the
distribution
system
is
six
to
eight
days.

Pump
stations:
Station
#
1
is
located
at
the
ground
storage
tank
(
in
Pineville).
This
pump
is
primarily
used
during
peak
demands
and
low
pressure
situations.
The
pump
is
timed
to
turn
on
in
the
morning
and
evening
during
peak
demand
and
when
the
pressure
drops
below
40
psi
at
a
point
downstream
of
the
pump
station.

Stations
#
2
and
#
3.
These
pumps
are
used
to
boost
system
pressure
when
the
pressure
in
the
areas
downstream
of
these
pumps
(
Weeping
Willow
and
Poplarville)
drops
below
40
psi.

Booster
chlorination
facilities:
Facility
#
1
is
located
on
Cherry
Hill
Ave.
(
downstream
of
the
Cherry
Hill
storage
tank
at
pump
station
#
3).
This
facility
is
occasionally
used
during
the
summer
when
remote
locations
downstream
of
the
booster
chlorination
facility
lose
residual.

Facility
#
2
is
located
at
the
intersection
of
Second
Ave.
and
11th
St.
(
in
a
mixing
zone)
in
an
area
of
the
distribution
system
where
chlorine
residuals
are
frequently
low.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
3
Poplarville
Softwood
River
WTP
Hardwood
WTP
Elevated
Storage
Tank
Ground
storage
tank
Pump
station
Chlorine
Booster
Station
Appleville
Weeping
Willow
Oakville
Pineville
Cedarville
Cypressville
Downtown
Industrial
Park
PS2
CB2
PS3
CB1
PS1
Elm
City
Water
Distribution
System
Apple
Drive
EST
Jackson
EST
Cherry
Hill
EST
Pineville
GST
East
EST
2.
Schematic
of
the
distribution
system:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
4
3.
SMP
monitoring
requirements:

The
Elm
City
system
serves
approximately
160,000
people
and
has
two
surface
water
plants.
Therefore,
a
total
of
16
SMP
sample
sites
(
8
per
plant)
are
required
to
be
sampled
approximately
every
60
days
for
one
year
(
6
dual
sample
sets
per
site)
for
TTHM
and
HAA5.
Because
it
uses
chlorine
as
a
disinfectant
in
the
distribution
system,
three
sites
representative
of
high
TTHM
are
required,
but
only
one
site
near
the
entry
point
is
required.

Required
SMP
Sample
Sites
SMP
Site
Type
Number
of
Sites
in
the
Hardwood
Plant
Influence
Zone
Number
of
Sites
in
the
Softwood
River
Plant
Influence
Zone
Near
entry
to
the
distribution
system
1
1
Average
residence
time
2
2
Representative
of
high
TTHM
3
3
Representative
of
high
HAA5
2
2
Available
Data:

Report
all
data
that
helped
in
sample
site
selection.
If
you
have
bromide,
TOC,
or
HPC
data,
these
may
be
helpful
for
justifying
Stage
2B
site
selection.
For
this
example,
only
tables
with
limited
data
are
presented
for
Stage
1
DBPR
sample
sites
and
the
sites
chosen
as
SMP
sample
sites.
Your
report
should
include
data
for
all
sites
that
were
considered
for
SMP
sites.

Chlorine
residual
and
HPC
data
were
available
for
Total
Coliform
Rule
sample
sites
and
the
8
Stage
1
DBPR
sample
sites.
The
chlorine
data
for
the
summer
months
of
June,
July,
August,
and
September
were
reviewed,
and
monthly
averages
and
an
overall
average
were
calculated.
Table
E.
1
presents
these
data
and
shows
which
sites
were
chosen
as
SMP
sites.

Quarterly
HPC
data
was
also
available
for
the
same
year
and
at
the
same
sites
as
the
free
chlorine
data.
The
four
results
for
each
site
were
averaged.
The
quarterly
results
and
yearly
average
values
are
presented
in
Table
E.
2.
The
results
are
ordered
based
on
the
Stage
1
DBPR
and
SMP
site
numbers.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
5
Table
E.
1
Elm
City
Distribution
System
 
Free
Chlorine
Residual
(
Cl2)
Data
Sample
Site
ID
#
Source/
Plant
Stg.
1
Site
Type
SMP
Site
#
SMP
Site
Type
Free
Chlorine
Residual
(
mg/
L)

June
July
Aug.
Sept.
Avg.

Stg.
1
#
1
SRP
Avg.
0.6
0.9
1.1
0.8
0.9
Stg.
1
#
2
SRP
Avg.
0.6
0.7
0.8
1.2
0.8
Stg.
1
#
3
SRP
Avg.
0.3
0.6
0.3
0.2
0.4
Stg.
1
#
4
SRP
Max.
0.2
0.3
0.5
0.3
0.6
Stg.
1
#
5
HP
Avg.
0.9
0.7
1.0
1.2
1.0
Stg.
1
#
6
HP
Avg.
0.2
0.8
0.8
0.5
0.6
Stg.
1
#
7
HP
Avg.
0.8
0.9
0.3
0.8
0.7
Stg.
1
#
8
HP
Max.
0.2
1.0
0.7
0.1
0.6
TCR
#
5
HP
1
E
1.6
1.4
1.6
1.5
1.5
TCR
#
4
HP
2
A
0.8
0.6
0.9
0.8
0.8
TCR
#
15
HP
3
A
0.6
0.4
0.4
0.4
0.5
TCR
#
16
HP
4
H
0.6
0.2
0.5
0.4
0.4
TCR
#
8
HP
5
H
0.4
0.3
0.3
0.5
0.4
TCR
#
2
HP
6
T
0.3
0.4
0.2
0.2
0.3
TCR
#
9
HP
7
T
0.3
0.2
0.2
0.4
0.3
TCR
#
12
HP
8
T
ND
0.1
0.1
0.3
0.1
TCR
#
10
SRP
9
E
1.4
1.2
0.9
1.7
1.3
TCR
#
11
SRP
10
A
0.6
0.6
0.5
0.9
0.7
TCR
#
13
SRP
11
A
0.5
0.3
0.4
0.5
0.6
TCR
#
6
Mix/
SRP
12
H
0.7
0.4
0.8
1.0
0.7
TCR
#
1
SRP
13
H
0.5
0.8
0.9
0.4
0.7
TCR
#
7
Mix/
SRP
14
T
0.3
0.4
0.7
0.6
0.5
TCR
#
3
SRP
15
T
0.2
0.6
0.3
0.2
0.3
TCR
#
14
Mix/
SRP
16
T
0.6
0.7
0.6
0.6
0.6
Distribution
System
Warm
Months
Average
0.6
Mix
­
Mixing
Zone
TCR
­
Total
Coliform
Rule
E
­
Near
Entry
Point
HP
­
Hardwood
Plant
Stg.
1
­
Stage
1
DBPR
A
­
Average
Residence
Time
SRP
­
Softwood
River
Plant
ND
­
Non­
Detection
T
­
Representative
High
TTHM
H
­
Representative
High
HAA5
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
6
Table
E.
2
Elm
City
Distribution
System
 
Heterotrophic
Plate
Counts
(
HPC)
Data
Sample
Site
ID
#
Source/
Plant
Stg.
1
Site
Type
SMP
Site
#
SMP
Site
Type
HPC
(
cfu/
mL)

4th
Qtr.
1st
Qtr.
2nd
Qtr.
3rd
Qtr.
Avg.

Stg.
1
#
1
SRP
Avg.
56
42
276
345
180
Stg.
1
#
2
SRP
Avg.
82
136
246
146
152
Stg.
1
#
3
SRP
Avg
140
215
615
557
382
Stg.
1
#
4
SRP
Max
280
163
263
446
288
Stg.
1
#
5
HP
Avg.
140
66
236
364
201
Stg.
1
#
6
HP
Avg.
50
42
222
223
134
Stg.
1
#
7
HP
Avg
53
42
72
84
63
Stg.
1
#
8
HP
Max
196
45
425
653
330
TCR
#
5
HP
1
E
12
8
12
34
17
TCR
#
4
HP
2
A
78
86
364
384
228
TCR
#
15
HP
3
A
35
62
92
147
84
TCR
#
16
HP
4
H
34
76
89
97
74
TCR
#
8
HP
5
H
68
43
57
79
62
TCR
#
2
HP
6
T
35
43
45
64
47
TCR
#
9
HP
7
T
156
278
359
169
240
TCR
#
12
HP
8
T
233
214
546
456
362
TCR
#
10
SRP
9
E
67
14
42
35
40
TCR
#
11
SRP
10
A
43
34
224
156
114
TCR
#
13
SRP
11
A
54
65
65
573
189
TCR
#
6
Mix/
SRP
12
H
53
64
123
94
83
TCR
#
1
SRP
13
H
50
34
63
113
65
TCR
#
7
Mix/
SRP
14
T
69
43
43
37
48
TCR
#
3
SRP
15
T
70
212
332
356
242
TCR
#
14
Mix/
SRP
16
T
66
53
53
153
81
Mix
­
Mixing
Zone
TCR
­
Total
Coliform
Rule
E
­
Near
Entry
Point
HP
­
Hardwood
Plant
Stg.
1
­
Stage
1
DBPR
A
­
Average
Residence
Time
SRP
­
Softwood
River
Plant
T
­
Representative
High
TTHM
H
­
Representative
High
HAA5
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
7
4.
Summary
of
selected
SMP
sample
sites:

Present
the
rationale
for
the
selection
of
the
SMP
sample
sites
in
your
system,
as
well
as
a
schematic
showing
their
location
within
the
distribution
system.

Sample
sites
were
chosen
to
represent
diverse
geographical
areas
of
the
distribution
system.
Each
site
is
shown
on
the
map
of
the
distribution
system
in
section
I.
6.
Water
quality
data
obtained
from
residual
chlorine
(
Table
E.
1)
and
HPC
(
Table
E.
2)
monitoring
were
considered
in
the
selection
of
the
SMP
monitoring
sites.

SMP
Site
#
1
 
Entry
point
to
the
distribution
system
for
Hardwood
Water
Treatment
Plant.
This
site
is
where
the
first
group
of
customers
receives
water.

SMP
Site
#
2
 
Represents
average
residence
time
of
water
leaving
the
Hardwood
Plant.
Based
on
chlorine
monitoring
results
at
TCR
sample
sites,
we
identified
the
areas
within
the
system
where
chlorine
levels
equaled
approximately
50
percent
of
the
initial
residual
concentration
at
the
high
service
pumps
and
chose
this
site
from
within
those
areas.
There
are
no
storage
facilities
between
the
treatment
plant
and
this
site.

SMP
Site
#
3
 
Represents
average
residence
time
of
water
leaving
the
Hardwood
Plant.
Water
at
this
site
does
not
go
through
a
storage
facility,
but
the
chlorine
residual
is
generally
35
to
40
percent
of
the
Hardwood
Plant
finished
water
concentration.
We
attribute
this
loss
of
chlorine
to
the
fact
that
the
transmission
and
distribution
lines
serving
this
area
are
older
unlined
cast
iron
and
have
been
observed
to
show
significant
build­
up
of
corrosion
by­
products
(
tubercles).
We
believe
that
these
corrosion
by­
products
exert
a
chlorine
demand
that
results
in
lower
than
typical
chlorine
residual
at
this
site,
although
we
believe
it
has
a
lower
average
water
age
than
SMP
#
2.

SMP
Site
#
4
 
Represents
high
HAA5
levels.
Sample
site
is
in
an
area
approaching
the
perimeter
of
the
distribution
system.
Water
in
this
area
is
primarily
from
the
Hardwood
Plant.
Chlorine
residual
at
this
site
ranges
between
0.2
and
0.6
mg/
L,
and
the
heterotrophic
plate
count
is
consistently
below
100
cfu
per
mL
year
round.

SMP
Site
#
5
 
Represents
high
HAA5
levels.
We
have
over
7
years
of
data
from
this
site.
Water
at
this
site
is
from
the
Hardwood
Plant.
Chlorine
residual
levels
are
between
0.3
and
0.5
mg/
L,
and
heterotrophic
plate
count
is
below
100
cfu/
mL.

SMP
Site
#
6
 
Represents
high
TTHM
levels.
This
sampling
site
is
believed
to
receive
water
from
a
4
MG
ground
tank
located
in
the
Appleville
region
of
the
distribution
system
during
high
demand
periods
and
is
at
the
entrance
to
a
small
subdivision
cul­
de­
sac
in
the
Oakville
community.
This
site
is
near
the
predicted
edge
of
the
mixing
zone,
and
chlorine
residuals
at
this
site
are
generally
very
low,
indicating
this
may
be
a
hydraulic
dead
end.
The
sample
site
is
near
the
first
house
on
the
cul­
de­
sac
(
which
has
12
homes
total).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
8
SMP
Site
#
7
 
Represents
high
TTHM
levels.
This
site
is
near
the
edge
of
the
mixing
zone
between
the
Softwood
River
and
Hardwood
plant
influence
areas,
but
within
the
an
area
of
the
system
believed
to
receive
all
of
its
water
from
the
Hardwood
Plant.
Chlorine
residual
levels
ranged
between
0.2
and
0.4
mg/
L
at
this
site.

SMP
Site
#
8
 
Represents
high
TTHM
levels.
This
site
has
been
problematic
in
the
past
due
to
positive
total
coliform
test
results,
non­
detectable
chlorine
residuals,
high
heterotrophic
plate
count
results,
and
odor
complaints.
A
4­
inch
blow­
off
was
installed
downstream
of
this
site,
but
it
continues
to
have
periodic
poor
water
quality.
Water
in
this
area
is
from
the
Hardwood
Plant.

SMP
Site
#
9
 
Entry
point
to
the
distribution
system
for
the
Softwood
River
Water
Treatment
Plant.
This
site
is
just
after
the
high
service
pumps
at
the
Water
Treatment
Plant.

SMP
Site
#
10
 
Represents
average
residence
time.
Chlorine
residual
is
generally
50
to
60
percent
of
the
plant
finished
water
concentration.

SMP
Site
#
11
 
Represents
average
residence
time.
Water
does
not
go
through
a
storage
facility
but
the
chlorine
residual
is
generally
35
to
40
percent
of
the
plant
finished
water
concentrations.
The
transmission
and
distribution
lines
serving
this
area
are
older
unlined
cast
iron
with
build­
up
of
corrosion
by­
products
(
tubercles)
in
several
areas.
We
believe
these
corrosion
by­
products
exert
a
chlorine
demand,
lowering
chlorine
residual,
even
though
residence
time
is
less
than
in
areas
with
similar
chlorine
residual
concentrations.

SMP
Site
#
12
 
Represents
high
HAA5
levels.
At
this
site,
the
water
age
is
believed
to
be
greater
than
average
because
it
is
within
the
mixing
zone,
but
the
chlorine
residual
is
never
below
0.4
mg/
L
and
the
heterotrophic
count
plate
is
usually
low
(
below
100
cfu/
mL).

SMP
Site
#
13
 
Represents
high
HAA5
levels.
Our
Stage
1
DBPR
monitoring
results
indicate
that
the
high
HAA5
concentrations
move
around
our
system
depending
on
the
season
and
production
of
the
Hardwood
and
Softwood
River
Plants,
especially
in
the
areas
served
by
the
Softwood
River
Plant.

SMP
Site
#
14
 
Represents
high
TTHM
levels.
This
sample
site
is
located
in
a
zone
of
the
distribution
system
that
has
been
recently
developed.
This
connection
is
located
downstream
from
a
chlorine
booster
station.
Chlorine
residuals
are
normally
in
the
0.3
to
0.7
mg/
L
range.
Water
in
this
area
is
generally
a
mix
of
water
from
the
Hardwood
and
Softwood
River
Plants.

SMP
Site
#
15
 
Represents
high
TTHM
levels.
This
site
is
downstream
from
the
Cypressville
Storage
Tank,
a
1.5
million
gallon
elevated
storage
tank.
There
are
often
low
chlorine
residuals
in
the
areas
downstream
of
this
tank.

SMP
Site
#
16
 
Represents
high
TTHM
levels.
This
sampling
site
is
in
the
mixed
zone
before
the
last
group
of
connections
near
the
end
of
the
distribution
system.
This
area
receives
water
from
the
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
9
Jackson
Storage
Tank
and
water
that
bypasses
the
tank.
Water
from
this
area
can
vary
greatly
in
the
percentages
of
Softwood
River
and
Hardwood
Plant
water.

5.
SMP
Sample
Schedule:

Because
the
quarterly
Stage
1
DBPR
monitoring
is
the
only
DBP
monitoring
that
has
been
performed
in
the
Elm
City
system,
historic
DBP
data
is
available
for
only
the
months
of
January,
April,
July,
and
October.
July
has
regularly
had
the
highest
DBP
levels,
but
no
DBP
data
is
available
for
the
other
summer
months.
As
a
result,
we
also
reviewed
finished
water
temperature
from
two
years
of
TCR
sampling
records
and
determined
that
our
peak
month
for
distribution
system
water
temperature
is
August.
However,
we
also
found
that
July's
average
distribution
system
water
temperature
for
the
two
years
reviewed
was
only
0.5
º
C
less
than
August's.
Based
on
the
historic
DBP
data
and
minimal
difference
in
average
water
temperature,
we
concluded
that
July
is
the
controlling
month
for
the
Elm
City
distribution
system.
The
following
table
summarizes
our
planned
SMP
sample
dates
and
is
based
on
collection
of
our
samples
on
the
second
Monday
of
the
month.

Proposed
SMP
Sample
Schedule
Planned
Sample
Date
November
8,
2005
January
10,
2006
March
7,
2006
May
9,
2006
July
11,
2006
September
12,
2006
Dual
sample
sets
will
be
collected
from
each
of
the
16
SMP
sample
sites
on
or
close
to
the
listed
dates
and
analyzed
for
TTHM
and
HAA5
by
a
State­
certified
laboratory.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
10
Poplarville
MIXING
ZONE
Softwood
River
WTP
Hardwood
WTP
Elevated
Storage
Tank
Ground
storage
tank
Pump
station
Chlorine
Booster
Station
8
7
6
5
4
3
2
1
8
7
6
5
4
3
2
1
9
16
15
14
13
12
11
10
Stage
1
DBPR
site
TCR
/
Selected
SMP
site
Appleville
Weeping
Willow
Oakville
Pineville
Cedarville
Cypressville
Downtown
Industrial
Park
PS2
CB2
PS3
CB1
PS1
Elm
City
Influence
Zones
And
Sample
Sites
6.
Map
of
the
distribution
system
showing
major
transmission
mains,
numbered
Stage
1
DBPR
compliance
sites,
and
numbered
SMP
sample
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
11
II.
SMP
RESULTS
1.
Introduction:.

The
SMP
was
conducted
between
November
2004
and
September
2005.
The
following
table
summarizes
our
planned
SMP
sample
dates,
the
actual
dates
when
samples
were
collected,
and
the
reasons
for
deviations
from
the
plan.

Actual
SMP
Sample
Schedule
Planned
Sample
Date
Actual
Sample
Date
Explanation
November
8,
2005
November
8,
2005
On
schedule.

January
10,
2006
January
10,
2006
On
schedule.

March
7,
2006
March
11,
2006
M
a
j
o
r
s
n
o
w
s
t
o
r
m
c
r
e
a
t
e
d
hazardous
road
conditions
and
limited
access
to
sample
sites
May
9,
2006
May
9,
2006
On
schedule.

July
11,
2006
July
11,
2006
On
schedule.

September
12,
2006
September
12,
2006
On
schedule
2.
Summary
of
IDSE
SMP
and
Stage
1
DBPR
compliance
data:

All
DBP
results
from
the
SMP
and
concurrent
Stage
1
DBPR
compliance
monitoring
are
presented
in
this
section.
Table
E.
3
presents
the
DBP
results
for
the
SMP
sample
sites,
organized
by
plant,
then
in
order
of
highest
to
lowest
TTHM
average.
Table
E.
4
presents
the
DBP
results
for
the
Stage
1
DBPR
compliance
sample
sites
for
the
period
from
November
2004
to
August
2005.
Sites
proposed
as
Stage
2B
compliance
sites
are
shaded
within
the
tables.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
12
Table
E.
3.
Elm
City
 
IDSE
SMP
Monitoring
Results
SMP
Site
#
Plant
Site
Type
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Data1
LRAA
Data1
LRAA
1
Hardwood
entry
point
36,
42,
30,
25,
38,
28
33
50,
44,
43,
47,
48,
38
45
2
Hardwood
average
residence
time
54,
39,
42,
56,
60,
42
49
22,
29,
36,
40,
41,
30
33
3
Hardwood
average
residence
time
47,
40,
52,
43,
51,
41
46
20,
25,
25,
29,
27,
19
24
4
Hardwood
high
HAA5
33,
29,
41,
42,
44,
22
35
36,
43,
52,
51,
48,
38
45
5
Hardwood
high
HAA5
35,
40,
41,
37
46,
43
40
60,
59,
64,
55,
66,
54
60
6
Hardwood
high
TTHM
62,
60,
60,
64,
68,
70
64
42,
40,
33,
38,
46,
30
38
7
Hardwood
high
TTHM
68,
62,
54,
52,
72,
70
63
39,
45,
28,
33,
40,
32
36
8
Hardwood
high
TTHM
65,
61,
73,
71,
72,
64
68
41,
39,
46,
45,
39,
47
43
9
Softwood
River
entry
point
40,
42,
49,
38,
38,
46
42
43,
47,
40,
48,
45
10
Softwood
River
average
residence
time
42,
20,
58,
62,
62,
30
46
23,
56,
40,
52,
40,
28
40
11
Softwood
River
average
residence
time
47,
50,
41,
54,
48,
40
47
14,
20,
21,
23,
29,
19
21
12
Mix/
Softwood
River
high
HAA5
35,
29,
47,
37,
47,
27
37
36,
40,
46,
48,
40,
34
41
13
Softwood
River
high
HAA5
52,
35,
46,
42,
50,
38
44
56,
44,
65,
50,
50,
58
54
14
Mix/
Softwood
River
high
TTHM
56,
50,
55,
51,
61,
45
53
42,
30,
43,
38,
34,
42
38
15
Softwood
River
high
TTHM
48,
56,
70,
52,
65,
49
57
28,
40,
33,
38,
34,
42
35
16
Mix/
Softwood
River
high
TTHM
72,
49,
68,
55,
69,
53
61
20,
21,
38,
28,
19,
35
27
1Data
obtained
from
sampling
every
60
days
are
listed
in
order
for
November,
January,
March,
May,
July,
and
September
(
as
required
for
a
surface
water
supply
$
10,000).
Note:
Bold
text
and
shading
identify
proposed
Stage
2
DBPR
compliance
sites.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
13
Table
E.
4.
Elm
City
 
Stage
1
DBPR
Compliance
Monitoring
Results
Site
ID
#
Plant
Site
Type
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Data1
LRAA
Data1
LRAA
Stg.
1
#
1
Softwood
River
Average
45,
34,
56,
62
49
24,
32,
43,
45
36
Stg.
1
#
2
Softwood
River
Average
36,
42,
45,
45
42
47,
50,
55,
56
52
Stg.
1
#
3
Softwood
River
Average
32,
34,
48,
67
45
50,
62,
64,
65
59
Stg.
1
#
4
Softwood
River
Maximum
64,
68,
83,
74
72
21,
25,
26,
28
25
Stg.
1
#
5
Hardwood
Average
44,
20,
62,
42
42
34,
45,
33,
41
38
Stg.
1
#
6
Hardwood
Average
46,
49,
39,
50
46
22,
30,
39,
41
33
Stg.
1
#
7
Hardwood
Average
41,
22,
50,
59
43
4,
46,
64,
58
54
Stg.
1
#
8
Hardwood
Maximum
65,
50,
60,
73
62
19,
22,
37,
30
27
1Data
listed
in
order
for
October,
January,
April,
and
July
quarterly
sampling.
Note:
Bold
text
and
shading
identify
proposed
Stage
2B
compliance
sites.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
14
III.
PROPOSED
STAGE
2B
COMPLIANCE
MONITORING
SITES
1.
Site
Summary:

A
total
of
eight
Stage
2B
compliance
monitoring
sites
(
four
per
plant)
were
selected
from
the
Stage
1
DBPR
and
SMP
sites,
as
shown
in
the
previous
tables
and
as
summarized
in
the
following
table.
A
schematic
of
the
monitoring
sites
is
presented
in
section
III.
4.

Stage
2B
Proposed
Compliance
Monitoring
Sites
Stage
2B
Compliance
Sites
Previous
Site
ID
#

Site
#
Source/
Plant
Type
SMP
Site
#
Stage
1
DBPR
Site
#

1
Softwood
River
Average
Stg.
1
#
3
2
Softwood
River
High
HAA5
Stg.
1
#
21
3
Softwood
River
High
TTHM
16
4
Softwood
River
High
TTHM
Stg.
1
#
4
5
Hardwood
Average
Stg.
1
#
7
6
Hardwood
High
HAA5
5
7
Hardwood
High
TTHM
8
8
Hardwood
High
TTHM
Stg.
1
#
8
1
This
site
was
an
average
residence
time
site
under
Stage
1
DBPR,
but
represented
high
HAA5
concentrations
in
the
distribution
system.

2.
Justification
of
Site
Selections:

1.
Softwood
River
Plant
Average
Site
 
Although
Stage
1
DBPR
site
#
1
had
the
highest
TTHM
LRAA
of
the
Stage
1
average
residence
time
sites,
Stage
1
DBPR
site
#
3
was
chosen
because
the
TTHM
LRAAs
at
these
two
sites
were
similar,
but
the
HAA5
LRAA
at
Stage
1
DBPR
site
#
3
was
considerably
higher.
Therefore,
Stage
1
DBPR
site
#
3
was
chosen
as
Elm
City's
Stage
2B
site
#
1.

2.
Softwood
River
Plant
Representative
High
HAA5
Site
 
Stage
1
DBPR
site
#
2
and
SMP
site
#
13
had
similar
HAA5
LRAAs.
However,
Stage
1
site
#
2
was
chosen
as
the
Stage
2B
#
2
because
we
have
multiple
years
of
data
at
this
site,
and
this
will
allow
us
to
maintain
an
historical
record
at
this
site.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
15
3.
Softwood
River
Plant
Representative
High
TTHM
Sites
 
SMP
site
#
16
and
Stage
1
DBPR
site
#
4
were
chosen
as
Elm
City's
Stage
2B
sites
#
3
and
#
4,
respectively,
because
they
had
the
highest
TTHM
averages
over
the
SMP
sampling
period
among
all
Softwood
River
Plant
sample
sites.

4.
Hardwood
Plant
Average
Site
 
Stage
1
DBPR
site
#
7
had
the
highest
HAA5
LRAA
for
the
SMP
sampling
period,
much
higher
than
the
other
two
Stage
1
DBPR
average
residence
time
sites,
and
a
TTHM
LRAA
that
was
second
highest
among
the
Stage
1
DBPR
average
residence
time
sites.
Therefore,
Stage
1
DBPR
site
#
7
was
chosen
as
Elm
City's
Stage
2B
site
#
5.

5.
Hardwood
Plant
Representative
High
HAA5
Site
 
SMP
site
#
5
was
chosen
as
Elm
City's
Stage
2B
site
#
6
because
it
has
the
highest
HAA5
LRAA
of
all
the
Hardwood
Plant
sample
sites.

6.
Hardwood
Plant
Representative
High
TTHM
Sites
 
SMP
site
#
8
and
Stage
1
DBPR
site
#
8
were
chosen
as
Elm
City's
Stage
2B
sites
#
7
and
#
8,
respectively.
SMP
site
#
8
was
chosen
because
it
had
the
highest
TTHM
LRAA
of
all
the
Hardwood
Plant
sample
sites
during
the
SMP
period.
Stage
1
DBPR
site
#
8
was
chosen
for
several
reasons.
It
is
in
an
area
of
the
system
not
represented
by
other
Stage
2B
sites.
It
is
downstream
of
a
storage
tank.
It
will
provide
historical
continuity
in
DBP
sampling.
It
had
a
single
sample
TTHM
result
higher
than
the
highest
single
sample
result
of
the
two
sites
that
had
higher
averages
(
73
vs.
72
and
70).
It
had
a
TTHM
LRAA
only
slightly
lower
than
the
two
SMP
sites
that
had
higher
averages
(
62
vs.
63
and
64)
and
achieved
this
average
with
a
warm
weather
sample
being
taken
in
only
one
month
(
July),
versus
the
three
warm
weather
samples
(
May,
July,
and
September)
taken
at
the
SMP
sites.

3.
Proposed
Stage
2B
Compliance
Monitoring
Schedule
Stage
2B
compliance
monitoring
will
be
scheduled
for
January,
April,
July,
and
October,
the
same
as
Stage
1
DBPR
and
Stage
2A
DBPR
sampling,
for
consistency
and
because
the
difference
in
distribution
system
water
temperature
between
July
and
August
is
minimal
(
average
0.5
º
C
higher
in
August,
based
on
a
review
of
2
years
of
TCR
sampling
records).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
E­
16
Poplarville
MIXING
ZONE
Softwood
River
WTP
Hardwood
WTP
Elevated
Storage
Tank
Ground
storage
tank
Pump
station
Chlorine
Booster
Station
Appleville
Weeping
Willow
Oakville
Pineville
Cedarville
Cypressville
Downtown
Industrial
Park
PS2
CB2
PS3
CB1
PS1
Elm
City
Stage
2B
DBPR
Compliance
Sample
Sites
Stage
2B
DBPR
Highest
TTHM
Stage
2B
DBPR
Highest
HAA5
Stage
2B
DBPR
Average
Residence
Time
#

#
#
1
5
3
4
8
7
2
6
4.
Map
of
Proposed
Stage
2B
Compliance
Monitoring
Sites:
Appendix
F
IDSE
SMP
Report
for
Producing
Ground
Water
Systems
Serving
$
10,000
People
This
appendix
is
provided
as
an
example
IDSE
report
for
producing
ground
water
systems
serving
at
least
10,000
people
and
opting
to
complete
the
Standard
Monitoring
Program
(
SMP).

Chapter
6
presents
the
detailed
SMP
requirements
for
these
systems,
and
Chapter
8
provides
guidance
on
selecting
SMP
sites
and
Stage
2B
compliance
monitoring
sites
based
on
SMP
results.
Chapter
8
also
presents
the
IDSE
reporting
requirements.
The
application
of
the
basic
guidance
on
SMP
site
selection
and
Stage
2B
compliance
monitoring
site
selection
is
shown
in
this
example,
along
with
several
instances
of
the
use
of
best
professional
judgement
being
applied.

The
italicized
text
within
the
appendix
consists
of
comments
and
explanations
and
is
not
intended
to
represent
the
recommended
content
of
an
actual
IDSE
Report.
This
page
intentionally
left
blank.
Initial
Distribution
System
Evaluation
Report
for
Oak
City
PWSID
Number:
US5555555
Address:
124
Oak
Drive
Oak
City,
US
11111­
1234
Contact
Person:
Mr.
Joseph
Smith,
P.
E.

Phone
Number:
123­
555­
1111
Fax
Number:
123­
555­
2222
Email
Address:
Jsmith@
ci.
oakcity.
us
System
Type:
Community,
ground
water
Population
Served:
200,000
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
1
I.
SMP
PLAN
1.
System
Description:

This
section
of
the
report
should
include
a
summary
of
typical
system
operating
characteristics
(
and
how
they
change
on
a
seasonal
basis
if
appropriate)
explaining
how
sources
are
used
to
meet
system
demands,
where
high
water
age
is
expected
to
occur,
and
any
special
aspects
of
operation
that
could
affect
DBP
concentrations
in
the
distribution
system.
Information
about
water
treatment
processes
and
source
water
quality
data
should
also
be
in
this
section,
including
a
brief
description
of
the
water
treatment
process
train.

General
system
characteristics:
Service
area:
Oak
City
plus
surrounding
suburban
areas
Production:
Annual
average
daily
demand
=
20
MGD
Source
Water
Information:
Silver
Springs
Wellfield
(
Silver
Aquifer)
pH:
from
7.0
to
7.5
Alkalinity:
from
125
to
175
mg/
L
as
CaCO3
TOC:
from
1.4
to
2.7
mg/
L
as
C
Blue
Springs
Wellfield
(
Blue
Aquifer)
pH:
from
6.9
to
7.3
Alkalinity:
from
82
to
198
mg/
L
as
CaCO3
TOC:
from
2.1
to
3.7
mg/
L
as
C
Entry
points
and
service
areas
under
the
influence
of
each
entry
point:
(
Entry
points
should
be
tied
to
source(
s)
and
typical
flows
noted.)

Entry
points:
Silver
Plant
(
Silver
Springs
Wellfield),
25
MGD
production
capacity
Winter
Average
Production
=
18
MGD
Summer
Average
Production
=
20
MGD
Blue
Pumping
Station
(
Blue
Springs
Wellfield),
10
MGD
production
capacity
Winter
Average
Production
=
0
MGD
Summer
Average
Production
=
6
MGD
The
second
supply
source
(
Blue
Springs
Wellfield)
is
necessary
to
cope
with
higher
demand
during
the
summer.
The
two
wellfields
draw
from
two
different
aquifers.

When
the
Blue
Pumping
Station
is
in
service,
customers
located
in
the
Cypressville,
Cedarville,
Poplarville,
and
north
downtown
generally
receive
water
from
the
Blue
Springs
Wellfield.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
2
Customers
located
in
the
Elmville,
Oakville,
Pineville,
and
south
downtown
generally
receive
water
from
the
Silver
Plant
year
round.

Customers
located
in
the
Weeping
Willow
Community,
Appleville,
and
central
downtown
generally
receive
a
mixture
of
water
from
both
plants
when
both
the
Silver
Plant
and
Blue
Pumping
Station
are
in
service.

Treatment
Provided:
Silver
Plant:
Direct
filtration,
chlorination,
in
service
12
months
per
year.
Blue
Pumping
Station:
Chlorination,
in
service
approximately
three
months
per
year,
during
the
summer
(
over
60
consecutive
days
of
operation).
Primary
and
residual
disinfection:
Chlorine/
chloramines
at
both
plants.

Description
of
distribution
system:
Distribution
system
(
estimated
length
of
lines
and
range
of
diameter):
About
600
miles,
4"
­
56"

The
estimated
range
of
residence
time
of
water
in
the
distribution
system
is
0
to
6
days.

5
storage
tanks
1
ground
tank
4
MG
capacity
4
elevated
tanks
6
MG
total
capacity
(
1.5
MG
each)

Pump
stations:
Station
#
1
is
located
at
the
ground
storage
tank.
This
pump
is
primarily
used
during
peak
demands
and
low
pressure
situations.
The
pump
is
timed
to
turn
on
in
the
morning
and
evening
during
peak
demand,
and
when
the
pressure
drops
below
40
psi
downstream
of
the
station.

Stations
#
2
and
#
3.
These
pumps
are
used
to
boost
system
pressure
when
the
pressure
in
the
areas
downstream
of
these
pumps
(
Poplarville
and
Weeping
Willow)
drops
below
40
psi.

Booster
facilities:
Both
facilities
are
total
chlorine
paced,
and
the
target
dose
after
boosting
is
3.0
to
3.5
mg/
L.
Ammonia
is
added
(
residual
ammonia
before
boosting
is
accounted
for)
to
target
a
Cl2:
NH3­
N
ratio
of
4.5
to
4.0.

Facility
#
1
is
located
on
Industrial
Park
Ave.
(
downstream
from
the
Courthouse
storage
tank
at
pump
station
#
3).
This
facility
is
occasionally
used
during
the
summer
when
low
total
chlorine
residual
(
below
1.0
mg/
L)
are
measured
at
remote
locations
downstream
of
the
booster
facility.

Facility
#
2
is
located
at
the
intersection
of
First
Ave.
and
13th
St.
(
in
a
mixing
zone)
in
an
area
of
the
distribution
system
where
total
chlorine
residuals
are
frequently
low.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
3
Pineville
Oakville
Elmville
Weeping
Willow
Downtown
Appleville
Poplarville
Cedarville
Cypressville
MIXING
ZONE
Blue
Pumping
Station
(
seasonal
source)

Silver
Plant
Elevated
Storage
Tank
Ground
storage
tank
Pump
station
Booster
disinfection
station
2
1
3
P
P
P
P
Stage
1
DBPR
site
SMP
site
1
4
2
Oak
City
Distribution
System
2.
Schematic
of
the
distribution
system
with
SMP
and
Stage
1
DBPR
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
4
3.
SMP
monitoring
requirements:

The
system
serves
approximately
200,000
people
and
uses
two
ground
water
sources.
Therefore,
a
total
of
4
SMP
sample
sites
(
2
per
plant)
must
be
sampled
approximately
every
90
days
(
4
dual
sample
sets
per
quarter)
for
the
IDSE.

Required
SMP
Sample
Sites
SMP
Site
Type
Number
of
Sites
in
the
Silver
Plant
Influence
Zone
Number
of
Sites
in
the
Blue
Station
Influence
Zone
Representative
of
high
TTHM
1
1
Representative
of
high
HAA5
1
1
Available
Data:

Report
all
data
that
helped
in
site
selection.
If
you
have
bromide,
TOC,
or
HPC
data,
these
may
be
helpful
for
justifying
Stage
2B
site
selection.
For
this
example,
tables
with
data
from
Stage
1
DBPR,
Total
Coliform
Rule,
and
operational
sample
sites
are
presented.
The
sites
chosen
as
SMP
sample
sites
should
also
be
noted
for
reference.
Your
report
should
include
data
for
all
sites
that
were
considered
as
candidates
for
SMP
sites.

Total
chlorine
and
HPC
data
were
available
from
Total
Coliform
Rule
sample
sites
and
the
two
Stage
1
DBPR
sample
sites.
Distribution
system
water
temperature
varies
over
a
small
range
between
winter
and
summer,
so
chlorine
data
for
November,
February,
May,
and
August
were
reviewed,
and
monthly
averages
and
an
overall
average
were
calculated.
The
typical
average
water
age
at
each
site
was
also
estimated
based
on
results
from
the
distribution
system
hydraulic
model.
Table
F.
1
presents
this
data,
with
sites
grouped
by
summer
time
plant
service
area
and
then
ordered
from
low
to
high
by
the
yearly
average
total
chlorine
concentration.
The
selected
SMP
sample
sites
are
numbered
and
their
type
identified
for
reference.

Quarterly
HPC
data
were
available
for
the
same
year
and
at
the
same
sites
as
the
chlorine
data.
The
four
results
for
each
site
were
averaged.
The
quarterly
results
and
yearly
average
values
are
presented
in
Table
F.
2.
The
results
are
presented
following
the
order
based
on
the
yearly
average
HPC
values.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
5
Table
F.
1
Oak
City
Distribution
System
 
Total
Chlorine
Data
Sample
Site
ID
#
Source/
Plant
Stage
1
Site
Type
SMP
Site
#
SMP
Site
Type
Total
Chlorine
(
mg/
L)

Nov.
Feb.
May
Aug.
Mean
Oper
#
9
SP
1
T
0.4
0.3
0.5
0.9
0.5
TCR
#
9
SP
3
H
0.9
1.2
1.0
0.9
1.0
TCR
#
4
SP
0.9
1.6
0.8
0.6
1.0
Stg.
1
#
2
SP
Avg.
0.6
3.0
2.1
0.8
1.6
TCR
#
3
SP
1.8
1.8
1.5
2.7
2.0
TCR
#
6
SP
2.4
2.7
0.9
2.4
2.1
Oper
#
10
SP
1.8
1.3
2.4
3.6
2.3
Oper
#
20
SP
4.0
3.6
2.7
4.0
2.6
TCR
#
2
BP
2
T
0.6
1.2
0.9
1.0
0.9
TCR
#
5
BP
0.6
0.9
1.5
0.9
1.0
TCR
#
8
BP
4
H
1.8
1.3
1.6
0.9
1.4
TCR
#
1
BP
1.8
2.1
1.8
1.7
1.9
Stg.
1
#
1
BP
Avg.
0.6
2.4
2.4
1.5
1.7
Oper
#
1
BP
1.8
2.7
3.3
2.4
2.6
TCR
#
7
BP
2.7
2.1
3.0
3.6
2.9
Oper
#
30
BP
4.0
3.8
4.2
2.9
3.7
SP
­
Silver
Plant
TCR
­
Total
Coliform
Rule
T
­
Representative
High
TTHM
BP
­
Blue
Plant
Stg.
1
­
Stage
1
DBPR
H
­
Representative
High
HAA5
Oper.
­
Operational
sample
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
6
Table
F.
2
Oak
City
Distribution
System
 
Heterotrophic
Plate
Counts
(
HPC)

Sample
Site
ID
#
Source/
Plant
Stage
1
Site
Type
SMP
Site
#
SMP
Site
Type
HPC
(
cfu/
mL)

Nov.
Feb.
May
Aug.
Mean
Oper
#
9
SP
1
T
56
42
176
245
130
TCR
#
9
SP
3
H
54
65
65
82
67
TCR
#
4
SP
43
34
224
156
114
Stg.
1
#
2
SP
Avg.
55
60
85
125
81
TCR
#
3
SP
53
42
72
84
63
TCR
#
6
SP
35
62
92
80
67
Oper
#
10
SP
0
0
0
5
1
Oper
#
20
SP
0
0
0
0
0
TCR
#
2
BP
2
T
70
212
132
356
242
Oper
#
30
BP
0
0
4
1
1
TCR
#
5
BP
280
163
263
96
201
TCR
#
8
BP
4
H
57
72
37
77
68
TCR
#
1
BP
56
43
43
143
71
Stg.
1
#
1
BP
Avg.
25
52
82
70
57
Oper
#
1
BP
15
42
72
60
47
TCR
#
7
BP
2
1
12
25
10
SP
­
Silver
Plant
TCR
­
Total
Coliform
Rule
T
­
Representative
High
TTHM
BP
­
Blue
Plant
Stg.
1
­
Stage
1
DBPR
H
­
Representative
High
HAA5
Oper.
­
Operational
sample
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
7
4.
Summary
of
selected
SMP
sample
sites
Present
the
rationale
for
the
selection
of
the
SMP
sample
sites.

Sample
sites
were
chosen
to
represent
diverse
geographic
areas
of
the
distribution
system.
A
description
of
the
four
SMP
sites
for
the
Oak
City
metro
area
distribution
system
is
given
below.
The
distribution
system
map
in
section
I.
2
shows
these
sites.

SMP
Site
#
1
 
Chosen
to
represent
high
TTHM
levels
in
the
Silver
Plant
influence
zone
and
the
mixing
zone.
This
monitoring
site
is
located
before
the
last
group
of
connections
in
proximity
to
the
end
of
the
distribution
system
in
the
mixing
zone.
At
this
site,
water
demand
tends
to
be
low,
total
chlorine
levels
are
always
low
(
ranging
between
0.3
and
0.9
mg/
L)
and
heterotrophic
plate
counts
are
often
greater
than
200
cfu/
mL.

SMP
Site
#
2
 
Chosen
to
represent
high
TTHM
levels
in
the
Blue
Pumping
Station
influence
zone.
This
monitoring
site
is
located
after
the
first
group
of
connections
(
approximately
0.5
miles)
downstream
of
the
Courthouse
Reservoir
(
1.5
MG
elevated
storage
facility)
in
the
influence
zone
of
the
Blue
Pumping
Station.

SMP
Site
#
3
 
Chosen
to
represent
high
HAA5
levels
in
the
Silver
Plant
influence
zone.
Sample
tap
is
a
hose
bib
at
an
elementary
school
located
in
a
zone
of
the
distribution
system
with
water
age
greater
than
average.
Total
chlorine
levels
at
this
site
range
between
0.9
and
1.2
mg/
L,
and
the
heterotrophic
plate
count
is
consistently
below
100
cfu/
mL
throughout
the
year.

SMP
Site
#
4
 
Chosen
to
represent
high
HAA5
levels
in
the
Blue
Pumping
Station
influence
zone
and
the
mixing
zone.
This
site
is
a
dedicated
sampling
site
routinely
used
for
monitoring
water
quality
in
downtown
Oak
City.
In
this
area,
the
water
age
is
greater
than
the
average,
the
total
chlorine
is
never
below
0.9
mg/
L
and
the
heterotrophic
count
plate
is
usually
low
(
below
100
cfu/
mL).
This
area
is
believed
to
be
in
the
mixing
zone,
receiving
water
from
both
the
Blue
Pumping
Station
and
Silver
Plant.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
8
5.
SMP
Sample
Schedule
Because
the
quarterly
Stage
1
DBPR
monitoring
is
the
only
DBP
monitoring
that
has
been
performed
in
the
Oak
City
system,
historic
DBP
data
is
available
for
only
the
months
of
February,
May,
August,
and
November.
August
has
regularly
had
the
highest
DBP
levels.
No
other
DBP
data
is
available
for
any
other
months
of
the
year,
so
water
temperature
data
was
also
reviewed
to
see
which
month
of
the
year
had
the
warmest
water
temperature.
Our
review
of
three
years
of
finished
water
temperature
data
from
TCR
sample
sites
showed
that
distribution
system
water
was
warmest
in
August.
Therefore,
based
on
the
agreement
of
the
water
temperature
and
TTHM
and
HAA5
monitoring
results,
we
concluded
August
is
the
controlling
month
for
the
Oak
City
distribution
system.
The
following
table
summarizes
our
planned
SMP
sample
dates
and
is
based
on
sampling
on
the
second
Monday
of
the
month.

Proposed
SMP
Sample
Schedule
Planned
Sample
Date
November
8,
2005
February
14,
2006
May
9,
2006
August
8,
2006
Dual
sample
sets
will
be
collected
from
each
of
the
four
SMP
sample
sites
on
or
close
to
the
listed
dates
and
analyzed
for
TTHM
and
HAA5
by
a
State­
certified
laboratory.
Stage
1
DBPR
compliance
samples
will
be
collected
on
the
same
days.

6.
Map
of
the
distribution
system
showing
major
transmission
mains,
numbered
Stage
1
DBPR
compliance
sites,
and
numbered
SMP
sample
sites:

For
this
example,
the
map
in
Section
I.
2
was
used
to
show
SMP
sample
sites.
The
system
in
this
example
has
only
four
SMP
sites
and
two
Stage
1
DBPR
monitoring
sites.
Depending
on
the
size
of
your
system
and
the
number
of
sample
sites.
It
may
be
more
appropriate
(
for
clarity)
to
show
SMP
sites
on
a
separate
schematic
in
this
section.

See
map
in
section
I.
2.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
9
II.
SMP
RESULTS
1.
Introduction:

The
SMP
was
conducted
between
November
2005
and
August
2006.
The
following
table
presents
the
planned
SMP
sample
dates,
the
actual
dates
when
samples
were
collected,
and
the
reason
for
the
one
deviation
from
the
plan.

Actual
SMP
Sample
Dates
Planned
Sample
Date
Actual
Sample
Date
Explanation
November
8,
2005
November
8,
2005
On
schedule.

February
14,
2006
February
14,
2006
On
schedule.

May
9,
2006
May
9,
2006
On
schedule.

August
8,
2006
August
5,
2006
System
maintenance
was
planned
in
the
area
of
SMP
site
#
1
for
the
week
of
August
8
and
was
expected
to
require
extensive
system
flushing,
so
SMP
sampling
was
performed
on
the
prior
Friday.

2.
Summary
of
IDSE
SMP
data
and
Stage
1
DBPR
compliance
data:

All
DBP
results
from
the
SMP
and
concurrent
Stage
1
DBPR
compliance
monitoring
are
presented
in
the
following
tables.
The
first
table
presents
the
TTHM
and
HAA5
results
for
the
SMP
sample
sites
and
the
second
table
presents
the
results
for
the
Stage
1
DBPR
compliance
sampling
for
the
period
from
February
2005
to
August
2006.

Oak
City
IDSE
SMP
Monitoring
Results
SMP
Sample
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Monitoring
Results1
LRAA
Monitoring
Results1
LRAA
#
1
­
Representative
high
TTHM
(
Silver)
62,
71,
82,
85
75
21,
25,
26,
28
25
#
2
­
Representative
high
TTHM
(
Blue)
49,
68,
72,
69
65
20,
21,
38,
28
27
#
3
­
Representative
high
HAA5
(
Silver)
33,
29,
41,
42
36
43,
52,
48,
38
45
#
4
­
Representative
high
HAA5
(
Blue)
35,
29,
37,
47
37
36,
40,
46,
40
41
1
Data
obtained
from
sampling
every
90
days
are
listed
in
order
for
November,
February,
May,
and
August
(
as
required
for
a
ground
water
supply
serving
$
10,000
people).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
10
Oak
City
Stage
1
DBPR
Monitoring
Results
Stage
1
DBPR
Monitoring
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Monitoring
Results1
LRAA
Monitoring
Results1
LRAA
Maximum
residence
time
#
1
45,
34,
56,
62
49
24,
32,
43,
45
36
Maximum
residence
time
#
2
60,
68,
68,
98
74
42,
33,
30,
38
36
1
Data
obtained
from
sampling
every
90
days
are
listed
in
order
for
November,
February,
May,
and
August
(
as
required
for
a
ground
water
supply
serving
$
10,000
people).

III.
PROPOSED
STAGE
2B
COMPLIANCE
MONITORING
SITES
1.
Site
Selection:

Two
Stage
2B
compliance
sample
sites
were
selected
for
each
plant
from
the
one
Stage
1
DBPR
site
and
two
SMP
sample
sites
per
plant.
The
selections
were
based
on
the
TTHM
and
HAA5
LRAAs.
The
sites
with
the
highest
LRAAs
were
selected,
with
one
exception.
The
following
tables
rank
the
sites
based
on
their
TTHM
and
HAA5
LRAAs.
The
sites
proposed
as
Stage
2B
compliance
sites
are
shaded
in
the
tables.
A
schematic
of
the
sites
is
presented
in
section
III.
4.

Proposed
Stage
2B
Compliance
Monitoring
Sites
Silver
Plant
Blue
Pumping
Station
TTHM
HAA5
TTHM
HAA5
Site
LRAA
(
µ
g/
L)
Site
LRAA
(
µ
g/
L)
Site
LRAA
(
µ
g/
L)
Site
LRAA
(
µ
g/
L)

SMP
#
1
75
SMP
#
3
45
SMP
#
2
65
SMP
#
4
41
Stg.
1#
2
74
Stg.
1#
2
36
Stg.
1#
1
49
Stg.
1#
1
36
SMP
#
3
36
SMP
#
1
25
SMP
#
4
37
SMP
#
2
27
Note:
Bold
text
and
shading
identify
proposed
Stage
2
DBPR
compliance
sites.

2.
Justification
of
Site
Selections:

For
the
Silver
Plant,
the
proposed
site
for
highest
TTHM
is
Stage
1
DBPR
site
#
2.
This
site
had
a
LRAA
nearly
equal
to
the
highest
LRAA
(
74
vs.
75
µ
g/
L
at
SMP
#
1),
had
the
highest
single
test
result
for
TTHM
(
98
vs.
85
µ
g/
L
at
SMP
#
1),
and
had
a
higher
HAA5
average
than
SMP
#
1
(
36
vs
25
µ
g/
L).
Continuing
the
use
of
the
Stage
1
DBPR
site
will
also
allow
the
city
to
maintain
a
longer
continuous
historical
record
of
TTHM
concentrations
at
a
single
location.
The
proposed
site
for
highest
HAA5
is
SMP
#
3,
which
had
the
highest
HAA5
LRAA
of
the
three
Silver
Plant
sample
sites.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
11
For
the
Blue
Pumping
Station,
the
proposed
site
for
highest
TTHM
is
SMP
#
2,
since
it
had
the
highest
TTHM
average.
The
proposed
site
for
highest
HAA5
is
SMP
#
4,
which
had
the
highest
HAA5
average.

3.
Summary
of
Proposed
Compliance
Sites
and
Sampling
Schedule:

Stage
2B
Sample
Site
Site
Description
1.
Silver
Plant
Highest
TTHM
Old
Stage
1
DBPR
Site
#
2
2.
Silver
Plant
Highest
HAA5
SMP
Site
#
3
3.
Blue
Pumping
Station
Highest
TTHM
SMP
Site
#
2
4.
Blue
Pumping
Station
Highest
HAA5
SMP
Site
#
4
Dual
sample
set
Stage
2B
sampling
is
proposed
to
occur
in
March,
June,
August
(
peak
historical
month
for
TTHM
concentrations),
and
December.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
F­
12
Pineville
Oakville
Elmville
Weeping
Willow
Downtown
Appleville
Poplarville
Cedarville
Cypressville
MIXING
ZONE
Blue
Pumping
Station
(
seasonal
source)

Silver
Plant
1
2
2
Elevated
Storage
Tank
Ground
storage
tank
Pump
station
Booster
disinfection
station
P
P
P
P
4
3
Stage
2B
highest
HAA5
site
Stage
2B
highest
TTHM
site
#
#
Oak
City
Distribution
System
4.
Map
of
Proposed
Stage
2B
Compliance
Monitoring
Sites:
Appendix
G
IDSE
SMP
Report
for
Producing
Surface
Water
Systems
Serving
500
­
9,999
People
This
appendix
is
provided
as
an
example
IDSE
report
for
producing
surface
water
systems
serving
500
to
9,999
people
and
opting
to
complete
the
Standard
Monitoring
Program
(
SMP).

Chapter
6
presents
the
detailed
SMP
requirements
for
these
systems,
and
Chapter
8
provides
guidance
on
selecting
SMP
sites
and
Stage
2B
compliance
monitoring
sites
based
on
SMP
results.
Chapter
8
also
presents
the
IDSE
reporting
requirements.
The
application
of
the
basic
guidance
on
SMP
site
selection
and
Stage
2
B
compliance
monitoring
site
selection
is
shown
in
this
example,
along
with
several
instances
of
the
use
of
best
professional
judgement
being
applied.

The
italicized
text
within
the
appendix
consists
of
comments
and
explanations
and
is
not
intended
to
represent
the
recommended
content
of
an
actual
IDSE
Report.
This
page
intentionally
left
blank.
Initial
Distribution
System
Evaluation
Report
for
Lakeside
City
PWSID
Number:
US0000000
Address:
P.
O.
Box
1234
Lakeside
City,
US
22222­
1234
Contact
Person:
Ms.
Mary
Smith,
P.
E.

Phone
Number:
123­
555­
1111
Fax
Number:
123­
555­
2222
Email
Address:
Msmith@
ci.
lakeside.
us
System
Type:
Community,
surface
water
Population
Served:
3,000
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
1
I.
SMP
PLAN
1.
System
Description:

This
section
of
the
report
should
include
a
summary
of
typical
system
operating
characteristics
(
and
how
they
change
on
a
seasonal
basis
if
appropriate)
explaining
how
sources
are
used
to
meet
system
demands,
where
high
water
age
is
expected
to
occur,
and
any
special
aspects
of
operation
that
could
affect
DBP
concentrations
in
the
distribution
system.
Information
about
water
treatment
processes
and
source
water
quality
data
should
also
be
in
this
section,
including
a
brief
description
of
the
water
treatment
process
train.

General
System
Characteristics:
Service
area:
Lakeside
City
 
the
system
serves
an
area
within
a
three­
mile
radius
Production:
Annual
average
daily
demand
1
MGD
Source
Water
Information:
Deep
Lake
water
quality
data:
pH:
from
6.8
to
7.9
Alkalinity:
from
77
to
94
mg/
L
as
CaCO3
TOC:
from
1.6
to
4.4
mg/
L
as
C
Entry
points
(
tied
to
source(
s))
and
identification
of
service
area(
s)
under
the
influence
of
each
entry
point:
(
Entry
points
should
be
tied
to
source(
s)
and
typical
flows
noted)

Entry
points:
Deep
Lake
Plant
Design
Capacity
=
2.5
mgd
Average
Daily
Production
=
1.0
mgd
Treatment
Provided:

Deep
Lake
Plant:
alum
coagulation,
flocculation,
sedimentation,
and
dual
media
filters.
Disinfection:
chlorine
for
both
primary
and
secondary
disinfection.

Description
of
distribution
system:

Distribution
system
(
estimated
length
of
lines
and
range
of
diameter):
About
20
miles,
4"
­
12"

2
elevated
tanks
with
total
capacity
of
0.5
MG
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
2
A
pump
station
is
located
near
the
western
storage
tank
(
most
distant
from
the
plant).
This
pump
is
primarily
used
during
peak
demands
and
low
pressure
situations.
The
pump
is
timed
to
turn
on
in
the
morning
and
evening
during
peak
demand
and
when
the
pressure
drops
below
40
psi
at
a
point
downstream
of
the
pump
station.

The
residence
time
of
water
in
the
distribution
system
is
believed
to
average
approximately
2
days,
and
ranges
up
to
nearly
5
days.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
3
Deep
Lake
WTP
1
P
Elevated
Storage
Tank
P
Pump
Station
1
Stage
1
DBPR
site
SMP
TTHM
site
SMP
HAA5
site
#

#
2
Big
Industrial
Park
2.
Schematic
drawing
of
the
distribution
system
with
SMP
and
Stage
1
DBPR
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
4
3.
SMP
monitoring
requirements:

The
Lakeside
City
system
serves
approximately
3,000
people
and
has
one
surface
water
plant.
Therefore,
a
total
of
2
SMP
sample
sites
are
required
by
the
Stage
2
DBPR
to
be
sampled
approximately
every
90
days
(
2
dual
sample
sets
per
quarter).

Required
SMP
Sample
Sites
SMP
Site
Type
Number
of
Sites
Representative
of
high
TTHM
1
Representative
of
high
HAA5
1
Available
Data:

Report
all
data
that
helped
in
sample
site
selection.
If
you
have
bromide,
TOC,
or
HPC
data,
these
may
be
helpful
for
justifying
Stage
2B
site
selection.
For
this
example,
only
limited
tables
are
presented
with
data
for
Stage
1
DBPR
sample
sites
and
the
sites
chosen
as
SMP
sample
locations.
Your
report
should
include
data
for
all
sites
that
were
considered
as
candidates
for
SMP
sites.

Chlorine
residual
information
was
available
for
Total
Coliform
Rule
sample
sites,
the
Stage
1
DBPR
sample
site,
and
the
operational
sample
site.
In
addition,
HPC
data
was
available
for
Total
Coliform
Rule
sample
sites.
The
following
table
presents
these
data,
with
the
selected
SMP
sample
sites
numbered
and
their
type
identified
for
reference.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
5
Table
G.
1
Lakeside
Distribution
System
 
Free
Chlorine
Residual
Data
Sample
Site
ID
#
SMP
Site
#
SMP
Site
Type
Free
Chlorine
Residual
(
mg/
L)

7/
04
8/
04
9/
04
10/
04
11/
04
12/
04
1/
05
2/
05
3/
05
4/
05
5/
05
6/
05
7/
05
8/
05
9/
05
10/
05
Stg.
1
0.14
0.32
0.68
0.63
0.20
0.45
Oper.
#
1
1.5
1.5
1.4
1.2
1.1
1.2
1.1
1.1
1.2
1.2
1.4
1.4
1.4
1.5
1.3
1.2
TCR
#
3
1
T
0.12
0.10
0.22
0.34
0.44
0.48
0.65
0.62
0.59
0.65
0.62
0.24
0.23
0.25
0.39
0.44
TCR
#
2
2
H
0.41
0.42
0.46
0.51
0.58
0.48
0.70
0.60
0.72
0.61
0.54
0.42
0.42
0.40
0.47
0.51
TCR
#
1
0.32
0.35
0.42
0.54
0.75
0.66
0.82
0.70
0.70
0.91
0.55
0.46
0.36
0.35
0.40
0.64
TCR
­
Total
Coliform
Rule
T
­
Representative
High
TTHM
Stg.
1
­
Stage
1
DBPR
H
­
Representative
High
HAA5
Oper.
­
Operational
sample
Table
G.
2
Lakeside
Distribution
System
 
Heterotrophic
Plate
Counts
(
HPC)

Sample
Site
ID#
SMP
Site
#
SMP
Site
Type
HPC
(
cfu/
mL)

7/
04
10/
04
1/
05
4/
05
7/
05
10/
05
Stg.
1
468
223
76
72
423
98
Oper.
#
1
0
0
0
0
0
0
TCR
#
3
1
T
540
202
85
67
342
102
TCR
#
2
2
H
97
75
23
31
98
59
TCR
#
1
95
53
15
19
76
48
TCR
­
Total
Coliform
Rule
T
­
Representative
High
TTHM
Stg.
1
­
Stage
1
DBPR
H
­
Representative
High
HAA5
Oper.
­
Operational
sample
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
6
4.
Summary
of
the
selected
SMP
sample
sites:

Present
the
rationale
for
the
selection
of
the
SMP
sample
sites
in
your
system,
as
well
as
a
schematic
showing
their
locations
within
the
distribution
system.

The
system
has
only
one
source.
Therefore,
a
total
of
two
SMP
monitoring
sites
are
required
by
the
Stage
2
DBPR.
Each
monitoring
site
is
marked
on
the
map
of
the
distribution
system
(
see
section
I.
2).
Residual
chlorine
and
HPC
data
from
the
TCR
and
operational
monitoring
sites
(
see
Tables
G.
1
and
G.
2)
were
considered
in
the
selection
of
the
SMP
monitoring
sites.

SMP
Site
#
1
 
Chosen
to
represent
high
TTHM
levels.
This
monitoring
site
is
located
in
the
vicinity
of
TCR
sample
site
#
3,
and
before
the
last
group
of
connections
in
proximity
to
the
end
of
the
distribution
system.
At
this
site,
water
demand
tends
to
be
low,
chlorine
residuals
are
often
very
low
(
less
than
0.5
mg/
L)
and
heterotrophic
plate
counts
are
often
higher
than
100
cfu/
mL.

SMP
Site
#
2
 
Chosen
to
represent
high
HAA5
levels.
Sample
tap
is
a
hose
bib
at
an
elementary
school
located
in
a
zone
of
the
distribution
system
with
water
age
greater
than
average.
Chlorine
residual
at
this
site
is
never
below
0.4
mg/
L
(
range
is
between
0.4
and
0.7
mg/
L),
and
the
heterotrophic
plate
count
is
consistently
below
100
cfu/
mL
throughout
the
year.

5.
SMP
sample
schedule:

Because
the
quarterly
Stage
1
DBPR
monitoring
is
the
only
DBP
monitoring
that
has
been
performed
in
the
Lakeside
City
system,
historic
DBP
data
are
available
for
only
the
months
of
February,
May,
August,
and
November.
August
has
regularly
had
the
highest
DBP
levels.
No
other
DBP
data
are
available
for
any
other
months
of
the
year,
so
water
temperature
data
from
TCR
sample
sites
were
also
reviewed
to
see
which
month
of
the
year
had
the
warmest
water
temperature.
Our
review
of
3
years
of
temperature
data
showed
that
distribution
system
water
was
warmest
in
August.
Therefore,
based
on
the
agreement
of
the
water
temperature
and
TTHM
and
HAA5
monitoring
results,
we
concluded
that
August
is
the
controlling
month
for
the
Lakeside
City
distribution
system.
The
following
table
summarizes
our
planned
SMP
sample
dates,
which
are
based
on
sampling
on
the
second
Monday
of
the
month.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
7
Proposed
SMP
Sample
Schedule
Planned
Sample
Date
November
13,
2007
February
12,
2008
May
14,
2008
August
13,
2008
Dual
sample
sets
will
be
collected
from
each
of
the
2
SMP
sample
sites
on
or
close
to
the
listed
dates
and
analyzed
for
TTHM
and
HAA5
by
a
State­
certified
laboratory.
Stage
1
DBPR
compliance
samples
will
be
collected
on
the
same
days.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
8
II.
SMP
Results
1.
Introduction
The
SMP
was
conducted
between
November
2007
and
August
2008.
The
following
table
presents
the
planned
SMP
sample
dates,
the
actual
dates
when
samples
were
collected,
and
the
reason
for
the
one
deviation
from
the
plan.

Actual
SMP
Sample
Schedule
Planned
Sample
Date
Actual
Sample
Date
Explanation
November
13,
2007
November
13,
2007
On
schedule.

February
12,
2008
February
12,
2008
On
schedule.

May
14,
2008
May
14,
2008
On
schedule
August
13,
2008
August
17,
2008
One
of
the
sample
bottles
broke
from
the
August
10
sampling,
so
re­
sample
was
performed
4
days
later.

2.
Summary
of
IDSE
SMP
data
and
Stage
1
DBPR
compliance
data.

All
DBP
results
from
the
SMP
and
concurrent
Stage
1
DBPR
compliance
monitoring
are
presented
in
the
following
two
tables.
The
first
table
presents
the
TTHM
and
HAA5
results
for
the
SMP
sample
sites
and
the
second
table
presents
the
results
for
the
Stage
1
DBPR
compliance
sampling
for
the
period
from
November
2007
to
August
2008.

Lakeside
City
IDSE
SMP
Monitoring
Results
SMP
Sample
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Monitoring
Results1
LRAA
Monitoring
Results1
LRAA
#
1
­
Representative
high
TTHM
63,
53,
78,
89
71
21,
25,
32,
41
30
#
2
­
Representative
high
HAA5
38,
32,
48,
56
44
43,
49,
53,
63
52
1
Data
obtained
from
sampling
every
90
days
(
as
required
for
surface
water
supplies
serving
500­
9,999
people)
are
listed
in
order
for
November,
February,
May,
and
August.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
9
Lakeside
City
Stage
1
DBPR
Monitoring
Results
SMP
Sample
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Monitoring
Results1
Avg
Monitoring
Results1
Avg
Maximum
residence
time
56,
49,
79,
95
70
25,
30,
36,
51
36
3.
Proposed
Stage
2B
Compliance
Sites
and
Schedule:

Two
Stage
2B
compliance
sample
sites
were
selected
from
among
the
one
Stage
1
DBPR
and
two
SMP
sample
sites.
The
selections
were
based
on
the
TTHM
and
HAA5
LRAAs.
The
following
table
ranks
the
sites
based
on
their
TTHM
and
HAA5
LRAAs.
The
sites
proposed
as
Stage
2B
compliance
locations
are
shaded
in
the
table.

Proposed
Stage
2
B
Compliance
Sites
TTHM
HAA5
Site
LRAA
(
µ
g/
L)
Site
LRAA
(
µ
g/
L)

SMP
#
1
71
SMP
#
2
52
Stage
1
70
Stage
1
36
SMP
#
2
44
SMP
#
1
30
Note:
Bold
text
and
shading
identify
proposed
Stage
2B
compliance
sites.

The
proposed
highest
HAA5
site
is
SMP
#
2,
which
had
the
highest
LRAA
of
the
three
sample
locations.
The
proposed
highest
TTHM
site
is
the
Stage
1
DBPR
site.
This
site
had
an
LRAA
nearly
equal
to
the
highest
LRAA
(
70
vs.
71
µ
g/
L
at
SMP
#
1),
and
had
the
highest
single
test
result
for
TTHM
(
95
vs.
89
µ
g/
L
at
SMP
#
1).
It
also
had
a
higher
HAA5
LRAA
than
SMP
#
1
(
36
vs.
30
µ
g/
L).
Continuing
to
use
the
Stage
1
DBPR
site
will
also
allow
the
city
to
maintain
a
continuous
historical
record
of
TTHM
concentrations
at
a
single
location.

Dual
sample
set
Stage
2
B
sampling
is
proposed
to
occur
in
March,
June,
August
(
peak
historical
month
for
TTHM
concentrations),
and
December.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
G­
10
Elevated
Storage
Tank
P
Pump
Station
Stage
2
high
HAA5
site
Stage
2
high
TTHM
site
Deep
Lake
WTP
P
Big
Industrial
Park
4.
Schematic
drawing
of
the
distribution
system
with
Stage
2B
sites:
Appendix
H
IDSE
Report
for
Producing
Ground
Water
Systems
Serving
<
10,000
People
This
appendix
is
provided
as
an
example
IDSE
report
for
producing
ground
water
systems
serving
less
than
10,000
people
and
opting
to
complete
the
Standard
Monitoring
Program
(
SMP).

Chapter
7
presents
the
detailed
SMP
requirements
for
these
systems,
and
Chapter
8
provides
guidance
on
selecting
SMP
sites
and
Stage
2B
compliance
monitoring
sites
based
on
SMP
results.
Chapter
8
also
presents
the
IDSE
reporting
requirements.
The
application
of
the
basic
guidance
on
SMP
site
selection
and
Stage
2B
compliance
monitoring
site
selection
is
shown
in
this
example,
along
with
several
instances
of
the
use
of
best
professional
judgement
being
applied.

The
italicized
text
within
the
appendix
consists
of
comments
and
explanations
and
is
not
intended
to
represent
the
recommended
content
of
an
actual
IDSE
Report.
This
page
intentionally
left
blank.
Initial
Distribution
System
Evaluation
Report
for
Greenspring
City
PWSID
Number:
US0000000
Address:
P.
O.
Box
1234
Greenspring
City,
US
11111­
1234
Contact
Person:
Ms.
Jennifer
Smith,
P.
E.

Phone
Number:
123­
555­
9876
Fax
Number:
123­
555­
9877
Email
Address:
Jsmith@
ci.
greenspring.
us
System
Type:
Community,
ground
water
Population
Served:
1,500
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
1
I.
SMP
PLAN
1.
System
Description:

This
section
of
the
report
should
include
a
summary
of
typical
system
operating
characteristics
(
and
how
they
change
on
a
seasonal
basis
if
appropriate)
explaining
how
sources
are
used
to
meet
system
demands,
where
high
water
age
is
expected
to
occur,
and
any
special
aspects
of
operation
that
could
affect
DBP
concentrations
in
the
distribution
system.
Information
about
water
treatment
processes
and
source
water
quality
data
should
also
be
in
this
section,
including
a
brief
description
of
the
water
treatment
process
train.

General
system
characteristics:
Service
area:
All
of
Greenspring
City
 
an
area
of
approximately
4
square
miles
Production:
Annual
average
daily
demand
­
250,000
gpd
Source
water
information:
Greenspring
Wellfield
water
quality
data:
pH
typically
ranges
from
6.8
­
7.5
Alkalinity
averages
185
mg/
L
as
CaCO
3
TOC
averages
1.5
mg/
L
as
C
Entry
points
(
tied
to
source
and
identification
of
service
area
under
influence
of
each):
(
Entry
points
should
be
tied
to
source(
s)
and
typical
flows
noted)

Green
Hill
Water
Plant
located
at
Greenspring
Wellfield
 
the
only
entry
point,
feeds
entire
distribution
system
Design
Capacity
=
1.0
mgd
Average
Daily
Production
=
0.25
mgd
Treatment
provided:
Green
Hill
Water
Plant
adds
chlorine
for
primary
and
secondary
disinfection
Description
of
distribution
system:
Distribution
system
(
estimated
length
of
lines
and
range
of
diameter):
About
7
miles,
4"
­
12"

Number
of
storage
tanks
and
total
storage
capacity:
1
ground
tank
at
the
Green
Hill
water
plant
(
0.05
MG)
and
1
elevated
tank
(
0.25
MG)

The
average
residence
time
of
water
in
the
distribution
system
is
believed
to
be
1
day,
and
may
range
up
to
nearly
3
days
at
the
ends
of
the
system.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
2
Elevated
Storage
Tank
Stage
1
DBPR
site
SMP
TTHM
site
SMP
HAA5
site
#

#
Green
Hill
Water
Plant
1
1
2
2.
Schematic
of
the
distribution
system:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
3
3.
SMP
monitoring
requirements:

The
Greenspring
City
system
serves
approximately
1,500
people.
This
is
a
ground
water
system,
served
by
one
aquifer.
Therefore,
for
the
IDSE,
a
total
of
2
SMP
sample
sites
must
be
sampled
approximately
every
six
months
(
2
dual
sample
sets
every
six
months).

SMP
Site
Requirements
Site
Criteria
Number
of
Sample
Sites
Representative
high
TTHM
1
Representative
high
HAA5
1
Available
Data:

Report
all
data
that
helped
in
sample
site
selection.
For
this
example,
only
tables
with
limited
data
are
presented
for
Stage
1
DBPR
sample
sites
and
the
sites
chosen
as
SMP
sample
locations.
If
you
have
bromide,
TOC
and/
or
HPC
data,
these
may
be
helpful
for
justifying
Stage
2B
site
selection.
Your
report
should
include
data
for
all
sites
that
were
considered
as
SMP
sites.

Chlorine
residual
was
available
for
the
system's
two
Total
Coliform
Rule
sample
sites,
the
Stage
1
DBPR
sample
site,
and
the
operational
sample
site.
The
following
table
presents
these
data,
with
SMP
site
numbers
and
types
provided
for
those
sites
chosen
for
SMP
monitoring.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
4
Table
H.
1
Greenspring
Distribution
System
 
Chlorine
Residual
Data
Sample
Site
ID
#
SMP
Site
#
SMP
Site
Type
Free
Chlorine
Residual
(
mg/
L)

1/
03
2/
03
3/
03
4/
02
5/
03
6/
03
7/
03
8/
03
9/
03
10/
03
11/
03
12/
03
1/
04
2/
04
3/
03
4/
04
5/
04
6/
04
7/
04
8/
04
9/
04
10/
04
11/
04
12/
04
Stg
1
0.25
0.28
TCR
#
2
1
TTHM
0.61
0.63
0.59
0.38
0.37
0.25
0.21
0.23
0.22
0.34
0.44
0.48
0.65
0.62
0.59
0.61
0.62
0.24
0.23
0.25
0.39
0.44
0.49
0.53
Avg.
2
HAA5
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
N/
A
TCR
#
1
0.73
0.68
0.55
0.42
0.42
0.40
0.41
0.42
0.46
0.51
0.58
0.48
0.70
0.60
0.72
0.61
0.54
0.42
0.42
0.40
0.47
0.51
0.56
0.48
FW
1.3
1.0
1.2
1.2
1.4
1.5
1.5
1.6
1.4
1.2
1.1
1.1
1.2
1.1
1.3
1.4
1.4
1.4
1.5
1.5
1.4
1.2
1.1
1.0
TCR
­
Total
Coliform
Rule
Stg.
1
­
Stage
1
DBPR
FW
­
Finished
Water
(
operational
sample
site)
Avg
­
Average
Residence
Time
(
operational
sample
site)
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
5
4.
Summary
of
selected
SMP
sample
sites:

Present
the
rationale
for
the
selection
of
the
SMP
sample
sites
in
your
system,
as
well
as
a
schematic
showing
their
locations
within
the
distribution
system.

SMP
Site
#
1
 
Chosen
to
represent
high
TTHM
levels.
This
is
TCR
site
#
2.
This
site
is
at
the
end
of
the
distribution
system,
before
the
last
significant
group
of
connections,
at
a
hose
bib
at
the
town
library.
It
is
located
near
TCR
monitoring
site
#
1,
downstream
of
the
storage
tank,
and
before
the
last
group
of
connections
in
proximity
to
the
end
of
the
distribution
system.
At
this
site,
chlorine
residuals
are
often
very
low
(
less
than
0.5
mg/
L).
This
site
also
represents
high
residence
time
within
the
distribution
system.

SMP
Site
#
2
 
Chosen
to
represent
high
HAA5
levels.
This
site
is
a
hose
bib
at
an
elementary
school
located
in
a
zone
of
the
distribution
system
with
water
age
greater
than
average
(
based
on
operators'
knowledge
of
the
distribution
system)
but
less
than
that
of
SMP
#
1.
Free
chlorine
is
not
routinely
monitored
at
this
site.
However,
this
site
is
expected
to
have
higher
chlorine
residual
than
the
TTHM
SMP
site,
and
therefore
less
potential
for
biodegradation.
This
site
was
also
chosen
to
provide
good
geographical
representation
of
the
distribution
system
(
although
TCR
#
1
had
free
chlorine
data,
it
was
physically
too
close
to
SMP
#
1
to
be
considered).

5.
SMP
sample
schedule:

Because
the
yearly
Stage
1
DBPR
monitoring
is
the
only
DBP
monitoring
that
has
been
performed
in
the
Greenspring
system,
historic
DBP
data
are
available
for
only
the
month
of
August.
No
other
DBP
data
are
available
for
any
other
months
of
the
year,
so
water
temperature
data
were
also
reviewed
to
see
which
month
of
the
year
had
the
warmest
water
temperature.
Our
review
of
3
years
of
finished
water
temperature
data
from
TCR
sample
sites
showed
that
distribution
system
water
was
warmest
in
August.
Therefore,
based
on
the
agreement
of
the
water
temperature
and
TTHM
and
HAA5
monitoring
results,
we
concluded
that
August
is
the
controlling
month
for
the
Greenspring
City
distribution
system.
The
following
table
summarizes
our
planned
SMP
sample
dates
and
is
based
on
sampling
on
the
second
Monday
of
the
month.

Proposed
SMP
Sample
Schedule
Planned
Sample
Date
February
12,
2008
August
13,
2008
Dual
sample
sets
will
be
collected
from
each
of
the
2
SMP
sample
sites
on
or
close
to
the
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
6
listed
dates
and
analyzed
for
TTHM
and
HAA5
by
a
State­
certified
laboratory.
Stage
1
DBPR
compliance
samples
will
be
collected
on
the
same
days.

II.
SMP
RESULTS
1.
Introduction:

The
SMP
was
conducted
in
February
and
August
2008.
The
following
table
presents
the
planned
SMP
sample
dates,
the
actual
dates
when
samples
were
collected,
and
the
reason
for
the
one
deviation
from
the
plan.

Actual
SMP
Sample
Schedule
Planned
Sample
Date
Actual
Sample
Date
Explanation
February
12,
2008
February
13,
2008
Sampler
was
sick
on
2/
12/
08
August
13,
2008
August
13,
2008
On
schedule
2.
Summary
of
IDSE
SMP
data
and
Stage
1
DBPR
compliance
data.

All
DBP
results
from
the
SMP
and
concurrent
Stage
1
DBPR
compliance
monitoring
are
presented
in
the
following
two
tables.
The
first
table
presents
the
TTHM
and
HAA5
results
for
the
SMP
sample
sites
and
the
second
table
presents
the
results
for
the
Stage
1
DBPR
compliance
sampling
for
the
period
from
February
2008
to
August
2008.

Greenspring
City
SMP
Monitoring
Results
SMP
Sample
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

2/
08
8/
08
LRAA
2/
08
8/
08
LRAA
#
1
­
Representative
high
TTHM
35
73
54
22
50
36
#
2
­
Representative
high
HAA5
25
55
40
23
49
36
Note:
Bold
text
and
shading
identify
proposed
Stage
2B
compliance
sites.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
7
Greenspring
City
Stage
1
DBPR
Monitoring
Results
Stage
1
DBPR
Sample
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

2/
08
8/
08
LRAA
2/
08
8/
08
LRAA
Maximum
Residence
Time
47
63
55
22
44
33
Note:
Bold
text
and
shading
identify
proposed
Stage
2B
compliance
sites.

3.
Proposed
Stage
2B
Compliance
Sites
and
Schedule:

Stage
2B
compliance
sample
sites
were
selected
from
among
the
two
SMP
sample
sites
and
one
Stage
1
DBPR
site.
The
selections
were
based
on
the
LRAAs
for
TTHM
and
HAA5.

Proposed
Stage
2B
Compliance
Sites
Stage
2B
Site
Number
Site
Type
Location
Description
1
Highest
TTHM
Stage
1
DBPR
#
1
2
Highest
HAA5
SMP
#
1
The
proposed
site
for
high
TTHM
is
the
Stage
1
DBPR
site,
which
had
an
LRAA
of
55
µ
g/
L.
The
highest
HAA5
LRAA
occurred
at
both
SMP
#
1
and
SMP
#
2.
The
HAA5
values
during
the
peak
temperature
months
were
similar
for
these
two
sites.
Because
SMP
#
1
has
a
higher
TTHM
LRAA
than
SMP
#
2,
it
was
chosen
as
the
second
Stage
2B
compliance
monitoring
site.
Dual
sample
set
Stage
2B
sampling
is
proposed
to
occur
in
February
and
August
(
the
peak
historical
month
for
TTHM
concentrations).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
8
Elevated
Storage
Tank
Stage
2
high
TTHM
site
Green
Hill
Water
Plant
#

#
Stage
2
high
HAA5
site
1
2
4.
Schematic
of
the
distribution
system
with
Stage
2B
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
H­
9
This
page
intentionally
left
blank.
Appendix
I
IDSE
SMP
Report
for
Producing
Surface
Water
Systems
Serving
<
500
People
This
appendix
is
provided
as
an
example
IDSE
report
for
producing
surface
water
systems
serving
less
than
500
people
and
opting
to
complete
the
Standard
Monitoring
Program
(
SMP).

Chapter
7
presents
the
detailed
SMP
requirements
for
these
systems,
and
Chapter
8
provides
guidance
on
selecting
SMP
sites
and
Stage
2B
compliance
monitoring
sites
based
on
SMP
results.
Chapter
8
also
presents
the
IDSE
reporting
requirements.
The
application
of
the
basic
guidance
on
SMP
site
selection
and
Stage
2B
compliance
monitoring
site
selection
is
shown
in
this
example,
along
with
several
instances
of
the
use
of
best
professional
judgement
being
applied.

The
italicized
text
within
the
appendix
consists
of
comments
and
explanations
and
is
not
intended
to
represent
the
recommended
content
of
an
actual
IDSE
Report.
This
page
intentionally
left
blank.
Initial
Distribution
System
Evaluation
Report
for
Riverdale
PWSID
Number:
US0000000
Address:
P.
O.
Box
1234
Riverdale,
US
22222­
1234
Contact
Person:
Mr.
John
Jones,
P.
E.

Phone
Number:
123­
555­
1111
Fax
Number:
123­
555­
2222
Email
Address:
JJones@
ci.
riverdale.
us
System
Type:
Community
ground
water
under
direct
influence
Population
Served:
300
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
I­
1
I.
SMP
PLAN
1.
System
Description:

This
section
of
the
report
should
include
a
summary
of
typical
system
operating
characteristics
(
and
how
they
change
on
a
seasonal
basis
if
appropriate)
explaining
how
sources
are
used
to
meet
system
demands,
where
high
water
age
is
expected
to
occur,
and
any
special
aspects
of
operation
that
could
affect
DBP
concentrations
in
the
distribution
system.

Information
about
water
treatment
processes
and
source
water
quality
data
is
also
part
of
this
section,
including
a
description
of
water
treatment
trains.
General
information
about
residence
times
within
the
distribution
system
should
also
be
included,
if
available.

General
System
Characteristics:
Service
area:
Riverdale
Production:
Annual
average
daily
demand
40,000
gpd
Source
Water
Information:
Green
Meadows
spring:
pH:
from
6.8
to
7.9
Alkalinity:
from
77
to
94
mg/
L
as
CaCO3
TOC:
from
1.6
to
2.4
mg/
L
as
C
Entry
points
(
tied
to
source(
s))
and
identification
of
service
area(
s)
under
the
influence
of
each
entry
point:
Entry
points:
Green
Meadows
well
field
Treatment
Provided:
Green
Meadows
well
field:
Direct
filtration
Primary
and
residual
disinfection:
Chlorine/
chlorine
Description
of
distribution
system:
Distribution
system
(
estimated
length
of
lines
and
range
of
diameter):
About
1
mile,
4"
­
6"

1
standpipe
with
total
capacity
of
50,000
gallons
Riverdale
did
not
receive
a
very
small
system
waiver
from
the
State
because
the
standpipe,
which
is
used
to
maintain
system
pressure
in
the
western
half
of
the
system,
was
considered
oversized
and
may
contribute
to
excessive
residence
times
in
the
tank.
Chlorine
residual
measurements
in
the
tank
show
that
it
may
be
operating
in
a
last­
in/
first­
out
mode,
and
water
at
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
I­
2
Green
Meadows
Well
Field
1
1
2
Elevated
Storage
Tank
Stage
1
DBPR
site
SMP
TTHM
site
SMP
HAA5
site
#

#
the
top
of
the
tank
may
be
much
older
than
water
in
the
bottom
of
the
tank.
Furthermore,
the
Green
Meadows
spring
is
situated
in
the
center
of
the
Riverdale
system,
while
the
Stage
1
DBPR
monitoring
site
is
located
on
the
east
side
of
the
system.
The
State
suggested
that
the
western
half
of
the
system
be
monitored,
upstream
and
downstream
of
the
storage
tank.

The
residence
time
of
water
in
the
distribution
system
is
thought
to
average
approximately
1
day,
but
is
probably
higher
near
the
standpipe.

2.
Schematic
drawing
of
the
distribution
system:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
I­
3
3.
SMP
monitoring
requirements:

The
Riverdale
system
serves
approximately
300
people.
This
is
a
system
using
ground
water
under
the
direct
influence
of
surface
water
and
is
served
by
one
plant.
Therefore,
a
total
of
2
SMP
sample
sites
are
required
by
the
Stage
2
DBPR
to
be
sampled
approximately
every
six
months
(
2
dual
sample
sets
every
six
months).

SMP
Site
Requirements
Site
Criteria
Number
of
Sample
Sites
Representative
high
TTHM
1
Representative
high
HAA5
1
Available
Data:

Provide
all
data
that
helped
in
site
selection.
You
can
include
are
data
from
Stage
1
DBPR,
Total
Coliform
Rule,
and
operational
sample
sites
(
any
site
not
used
for
rule
compliance).
You
should
also
provide
residence
times
in
the
distribution
system,
if
known.
If
you
have
bromide,
TOC,
or
HPC
data,
these
may
be
helpful
for
justifying
your
Stage
2B
site
selection.
Your
report
should
include
data
for
all
sites
that
were
considered
as
candidates
for
SMP
locations.

Chlorine
residual
information
was
available
at
Total
Coliform
Rule
and
operational
sample
sites.
A
summary
of
chlorine
residual
data
in
the
distribution
system
is
presented
in
Table
I.
1.
The
chlorine
residual
results
from
a
study
of
water
flow
through
the
storage
tank
are
shown
in
Table
I.
2.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
I­
4
Table
I.
1
Riverdale
Distribution
System
 
Chlorine
Residual
Data
Sample
Site
ID
Chlorine
Residual
(
mg/
L)

1/
05
2/
05
3/
05
4/
05
5/
05
6/
05
7/
05
8/
05
9/
05
10/
05
11/
05
12/
05
1/
06
2/
06
3/
06
4/
06
5/
06
6/
06
7/
06
8/
06
9/
06
10/
06
11/
06
12/
06
WF
#
1
1.3
1.0
1.2
1.2
1.4
1.5
1.5
1.6
1.4
1.2
1.1
1.1
1.2
1.1
1.3
1.4
1.4
1.4
1.5
1.5
1.4
1.2
1.1
1.0
TCR
#
1
0.71
0.62
0.59
0.41
0.37
0.27
0.23
0.21
0.23
0.35
0.43
0.48
0.63
0.62
0.58
0.62
0.61
0.31
0.25
0.24
0.41
0.44
0.51
0.62
WF
­
Wellfield
finished
water
TCR
­
Total
Coliform
Rule
Table
I.
2
Riverdale
Distribution
System
 
Chlorine
Residual
Data
at
Storage
Tank
Water
Depth1
Test
1
Test
2
Test
3
Average
1
ft
from
top
ND
ND
ND
ND
3
ft
from
top
ND
0.1
0.1
0.10
5
feet
from
top/
bottom
0.2
0.3
0.2
0.23
3
ft
from
bottom
0.7
0.9
0.8
0.80
1
ft
from
bottom
1.1
1.0
1.1
1.07
1
This
is
a
50
ft
tall
standpipe.
Note:
Data
collected
in
July
2004.
ND
­
Non
Detect
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
I­
5
4.
Summary
of
selected
IDSE
SMP
sites:

Present
the
rationale
for
the
selection
of
SMP
sample
sites
in
your
system,
as
well
as
a
schematic
showing
their
location
within
the
distribution
system.

A
description
of
the
two
SMP
sites
proposed
for
the
Riverdale
distribution
system
is
given
here.
Each
site
is
shown
on
a
map
of
the
distribution
system
in
section
I.
2.

SMP
Site
#
1
 
Chosen
to
represent
high
TTHM
levels.
This
site
is
located
downstream
of
the
standpipe
on
the
western
edge
of
town.
It
is
located
before
the
last
group
of
connections
in
proximity
to
the
end
of
the
distribution
system.
Because
water
with
high
residence
time
from
the
upper
portions
of
the
tank
is
thought
to
be
occasionally
drawn
into
the
distribution
system
during
peak
demand
periods,
this
site
has
the
potential
for
high
TTHM
levels.

SMP
Site
#
2
 
Chosen
to
represent
high
HAA5
levels.
This
site
is
a
hose
bib
located
upstream
(
prior
to)
of
the
storage
tank
on
the
western
edge
of
the
system.
This
site
has
average
residence
time
within
the
distribution
system,
and
chlorine
residual
is
expected
to
be
adequate
(
greater
than
0.5
mg/
L)
to
prevent
biodegradation.

5.
SMP
Sample
Schedule:

Annual
Stage
1
DBPR
monitoring
is
the
only
DBP
monitoring
that
has
been
performed
in
the
Riverdale
system.
As
a
result
historic
DBP
data
are
available
for
only
the
month
of
August.
DBP
data
is
not
available
for
any
other
months
of
the
year,
so
water
temperature
data
were
reviewed
to
see
which
month
of
the
year
had
the
warmest
water
temperature.
Our
review
of
three
years
of
finished
water
temperature
data
from
the
TCR
sample
site
showed
that
distribution
system
water
was
warmest
in
August.
Therefore,
we
concluded
that
August
is
the
controlling
month
for
the
Riverdale
distribution
system.
The
following
table
summarizes
our
planned
SMP
sample
dates
and
is
based
on
sampling
on
the
second
Monday
of
the
required
month.

Proposed
SMP
Sample
Schedule
Planned
Sample
Date
February
12,
2008
August
13,
2008
Dual
sample
sets
will
be
collected
from
each
of
the
2
SMP
sample
sites
on
or
close
to
the
listed
dates
and
analyzed
for
TTHM
and
HAA5
by
a
State­
certified
laboratory.
Stage
1
DBPR
compliance
samples
will
be
collected
on
the
same
day
in
August.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
I­
6
II.
SMP
RESULTS
1.
Introduction:

The
SMP
was
conducted
in
February
and
August
2008.
The
following
table
presents
the
planned
SMP
sample
dates,
the
actual
dates
when
samples
were
collected,
and
the
reason
for
the
one
deviation
from
the
plan.

Actual
SMP
Sample
Schedule
Planned
Sample
Date
Actual
Sample
Date
Explanation
February
12,
2008
February
13,
2008
A
blizzard
prevented
the
operator
from
getting
to
the
monitoring
sites
on
February
12.

August
13,
2008
August
13,
2008
On
schedule.

2.
Summary
of
IDSE
SMP
data
and
Stage
1
DBPR
compliance
data:

All
DBP
results
from
the
SMP
and
concurrent
Stage
1
DBPR
compliance
monitoring
are
presented
in
the
following
table.
The
table
presents
the
TTHM
and
HAA5
results
for
the
SMP
sample
sites
and
the
Stage
1
DBPR
compliance
site.

Riverdale
SMP
and
Stage
1
DBPR
Monitoring
Results
Monitoring
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

2/
08
8/
08
LRAA
2/
08
8/
08
LRAA
SMP
Site
#
1
­
Representative
high
TTHM
45
82
64
18
32
25
SMP
Site
#
2
­
Representative
high
HAA5
33
65
49
20
35
28
Stage
1
Maximum
residence
time
N/
A
78
N/
A
N/
A
45
N/
A
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
I­
7
III.
PROPOSED
STAGE
2B
COMPLIANCE
MONITORING
SITES
This
section
of
the
report
should
include
a
summary
of
your
proposed
Stage
2B
monitoring
sites
including
a
schematic
of
the
distribution
system
showing
their
locations,
a
discussion
of
the
rationale
for
your
selection
of
those
sites,
and
a
proposed
monitoring
schedule.

Stage
2B
compliance
sample
sites
were
selected
from
the
two
SMP
sample
sites
and
the
Stage
1
DBPR
site.
The
selections
were
based
on
a
comparison
of
the
average
TTHM
and
HAA5
values
at
the
SMP
sites
and
the
August
results
for
all
three
sites
(
two
SMP
and
one
Stage
1
DBPR
sites).
The
following
tables
rank
the
sites
based
on
their
average
TTHM
and
HAA5
values.
The
sites
proposed
as
Stage
2B
compliance
sites
are
in
bold
text
and
shaded
in
the
table.
A
schematic
of
the
monitoring
sites
is
presented
in
section
III.
2.

Proposed
Stage
2B
Compliance
Monitoring
Sites
TTHM
HAA5
Site
LRAA
(
µ
g/
L)
August
results
(
µ
g/
L)
Site
LRAA
(
µ
g/
L)
August
results
(
µ
g/
L
SMP
#
1
64
82
Stage
1
N/
A
45
Stage
1
N/
A
78
SMP
#
2
28
35
SMP
#
2
49
65
SMP
#
1
25
32
Bold
text
and
shading
identifies
proposed
Stage
2B
compliance
monitoring
sites.

The
proposed
highest
TTHM
site
is
SMP
#
1.
Of
the
three
locations,
SMP
#
1
has
the
highest
average
TTHM
value
as
well
as
highest
TTHM
value
during
the
peak
temperature
month
(
August).

The
proposed
highest
HAA5
site
is
the
Stage
1
DBPR
site.
This
site
has
the
highest
August
HAA5
value
of
the
three
sites.

Stage
2B
sampling
is
proposed
to
occur
in
August
(
peak
historical
month
for
TTHM
concentrations).
TTHM
samples
will
be
collected
at
SMP
#
1
only,
and
HAA5
will
be
collected
at
the
Stage
1
site
only.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
I­
8
Elevated
Storage
Tank
Stage
2B
High
HAA5
Stage
2B
High
TTHM
Green
Meadows
Well
Field
2.
Schematic
drawing
of
the
distribution
system
with
Stage
2
DBPR
sites:
Appendix
J
IDSE
SMP
Report
for
a
100
Percent
Purchasing
Surface
Water
System
This
appendix
is
provided
as
an
example
IDSE
report
for
surface
water
systems
purchasing
100
percent
of
their
water,
serving
100,000
­
499,999
people,
and
opting
to
complete
the
Standard
Monitoring
Program
(
SMP).

Chapter
5
presents
the
detailed
SMP
requirements
for
these
systems,
and
Chapter
8
provides
guidance
on
selecting
SMP
sites
and
Stage
2B
compliance
monitoring
sites
based
on
SMP
results.
Chapter
8
also
presents
the
IDSE
reporting
requirements.
The
application
of
the
basic
guidance
on
SMP
site
selection
and
Stage
2B
compliance
monitoring
site
selection
is
shown
in
this
example,
along
with
several
instances
of
the
use
of
best
professional
judgement
being
applied.

The
italicized
text
within
the
appendix
consists
of
comments
and
explanations
and
is
not
intended
to
represent
the
recommended
content
of
an
actual
IDSE
Report.
This
page
intentionally
left
blank.
Initial
Distribution
System
Evaluation
Report
for
Grove
City
PWSID
Number:
US1111111
Address:
1234
Main
Street
Grove
City,
US
99999
Contact
Person:
Ms.
Margaret
Doe,
P.
E.

Phone
Number:
123­
555­
0000
Fax
Number:
123­
555­
0001
Email
Address:
MDoe@
ci.
grovecity.
us
System
Type:
Community,
100
%
purchased
SW
Population
Served:
160,000
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
1
I.
SMP
PLAN
1.
System
Description:

This
section
of
the
report
should
include
a
summary
of
typical
system
operating
characteristics
(
and
how
they
change
on
a
seasonal
basis
if
appropriate)
explaining
how
sources
are
used
to
meet
system
demands,
where
high
water
age
is
expected
to
occur,
and
any
special
aspects
of
operation
that
could
affect
DBP
concentrations
in
the
distribution
system.

General
system
characteristics:
Service
area:
Grove
City
plus
surrounding
suburban
areas
Production:
Annual
average
daily
demand
15
MGD
Source
Water
Information:

The
wholesalers
do
not
provide
us
with
raw
water
quality
data,
but
our
purchasing
agreements
require
water
quality
at
our
city's
entry
points
to
meet
State
and
federal
drinking
water
quality
standards.

Entry
points
and
service
areas
under
the
influence
of
each
entry
point:
(
Entry
points
should
be
tied
to
source(
s)
and
typical
flows
noted)

Entry
points:
Purchase
approximately
50
percent
(
7.5
mgd
average)
from
Big
City
Purchase
remaining
50
percent
(
7.5
mgd
average)
from
New
City
Both
sources
provide
treated
surface
water
and
are
used
year
round.

Customers
located
in
the
Cypressville,
Cedarville,
Poplarville,
and
north
downtown
generally
receive
water
from
Big
City
Customers
located
in
the
Industrial
Park
area,
Oakville,
Pineville,
and
south
downtown
generally
receive
water
from
New
City
Customers
located
in
the
Weeping
Willow
Community,
Appleville,
and
central
downtown
generally
receive
a
mixture
of
water
from
both
plants
Treatment
Provided:
Big
City
 
conventional
treatment
followed
by
UF
New
City
 
conventional
treatment
Primary
and
residual
disinfection:
chlorine/
chloramines
at
both
sources.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
2
Description
of
distribution
system:
Distribution
system
(
estimated
length
of
lines
and
range
of
diameter):
About
400
miles,
4"
­
56"
(
approximately
20
MG
carrying
capacity)

5
storage
tanks
of
10
MG
total
capacity
1
ground
tank
4
MG
capacity
4
elevated
tanks
6
MG
total
capacity
(
1.5
MG
each)

The
average
residence
time
of
water
in
the
distribution
system
is
six
to
eight
days.

Pump
stations:
Station
#
1
is
located
at
the
ground
storage
tank
(
in
Pineville).
This
pump
is
primarily
used
during
peak
demands
and
low
pressure
situations.
The
pump
is
timed
to
turn
on
in
the
morning
and
evening
during
peak
demand,
and
when
the
pressure
drops
below
40
psi
at
a
point
downstream
of
the
pump
station.

Stations
#
2
and
#
3.
These
pumps
are
used
to
boost
system
pressure
when
the
pressure
in
the
areas
downstream
of
these
pumps
(
Poplarville
and
Weeping
Willow,
respectively)
drops
below
40
psi.

Booster
chloramination
facilities:
Facility
#
1
is
located
on
Cherry
Hill
Ave.
(
downstream
of
the
Cherry
Hill
storage
tank
at
pump
station
#
3
in
Weeping
Willow).
This
facility
is
occasionally
used
during
the
summer
when
remote
locations
downstream
of
the
booster
chloramination
facility
lose
total
chlorine
residual.

Facility
#
2
is
located
at
the
intersection
of
Second
Ave.
and
11th
St.
(
in
a
mixing
zone)
in
an
area
of
the
distribution
system
where
total
chlorine
residuals
are
frequently
low.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
3
Poplarville
Big
City
Purchased
Water
Entry
Point
New
City
Purchased
Water
Entry
Point
Elevated
Storage
Tank
Ground
storage
tank
Pump
station
Chlorine
Booster
Station
Appleville
Weeping
Willow
Oakville
Pineville
Cedarville
Cypressville
Downtown
Industrial
Park
PS2
CB2
PS3
CB1
PS1
Grove
City
Water
Distribution
System
Apple
Drive
EST
Jackson
EST
Cherry
Hill
EST
Pineville
GST
East
EST
2.
Schematic
drawing
of
the
distribution
system:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
4
3.
SMP
monitoring
requirements:

The
Grove
City
system
serves
160,000
people
and
purchases
only
surface
water.
Therefore,
a
total
of
24
SMP
sample
sites
are
required
to
be
sampled
approximately
every
60
days
for
one
year
(
6
dual
sample
sets
per
site)
for
TTHM
and
HAA5.

Required
SMP
Sample
Sites
Site
Criteria
Number
of
Sample
Sites
Near
entry
to
the
distribution
system
21
Average
residence
time
6
Representative
of
high
HAA5
7
Representative
of
high
TTHM
9
1
The
Stage
2
rule
requires
4
near­
entry
point
SMP
sites
for
our
size
of
system.
However,
because
we
only
have
two
consecutive
entry
points,
the
other
two
were
divided
among
high
TTHM
and
HAA5
sites.

Available
Data:

Report
all
data
that
helped
in
site
selection.
For
this
example,
tables
are
presented
with
limited
data
for
Stage
1
DBPR
sample
sites
and
the
sites
chosen
as
SMP
sample
locations.
Your
report
should
include
data
for
all
sites
that
were
considered
as
candidates
for
SMP
sites.
If
you
have
bromide,
TOC,
or
HPC
data,
these
may
be
helpful
for
justifying
Stage
2B
site
selections.

Total
chlorine
residual
and
HPC
data
were
available
at
our
Total
Coliform
Rule
and
Stage
1
DBPR
sample
sites.
The
chlorine
data
for
the
summer
months
of
June,
July,
August,
and
September
were
reviewed,
and
monthly
averages
and
an
overall
average
were
calculated.
These
data
are
presented
in
Table
J.
1.
The
SMP
sample
site
numbering
and
type
are
also
provided
for
reference.

Quarterly
HPC
data
were
available
for
the
same
year
and
at
the
same
sites
as
the
total
chlorine
data.
The
four
results
for
each
site
were
averaged.
The
monthly
results
and
overall
average
values
are
presented
in
Table
J.
2.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
5
Table
J.
1
Grove
City
Distribution
System
 
Total
Chlorine
Residual
Data
Sample
Site
ID
#
Source/
Plant
Stage
1
Type
SMP
Site
#
SMP
Type
Total
Chlorine
Residual
(
mg/
L)

June
July
Aug.
Sept.
Mean
TCR
#
9
NC
1
E
3.6
3.4
3.5
3.6
3.5
TCR
#
11
NC
2
A
2.9
2.7
3.2
2.4
2.5
TCR
#
22
NC
3
A
2.3
2.1
2.3
2.4
2.3
TCR
#
3
NC
4
A
2.4
2.7
2.3
2.5
2.5
TCR
#
46
NC
5
H
2.1
1.7
1.9
2.0
1.9
TCR
#
5
NC
6
H
1.0
1.2
1.1
1.0
1.1
TCR
#
6
NC
7
H
1.8
1.6
1.6
1.6
1.7
TCR
#
78
NC
8
T
0.9
0.9
1.2
0.9
1.0
TCR
#
81
NC
9
T
1.0
1.1
1.3
1.1
1.1
TCR
#
39
NC
10
T
1.7
1.8
1.7
1.7
1.7
TCR
#
10
NC
11
T
0.6
0.6
0.9
0.6
0.7
TCR
#
1
BC
12
E
3.4
3.2
3.7
2.9
3.3
TCR
#
86
BC
13
A
2.1
2.1
2.4
2.0
2.2
TCR
#
21
BC
14
A
2.0
1.8
2.0
1.9
1.9
TCR
#
35
BC
15
A
2.2
1.9
2.5
2.3
2.2
TCR
#
13
BC
16
H
2.0
2.3
1.9
2.4
2.2
TCR
#
49
BC
17
H
1.5
1.2
1.8
1.6
1.5
TCR
#
65
BC
18
H
1.9
2.2
1.8
2.3
2.1
TCR
#
16
MIX
19
T
2.5
2.6
2.8
2.9
2.7
TCR
#
51
BC
20
T
0.9
1.3
0.9
1.0
1.0
TCR
#
72
MIX
21
T
1.9
2.0
1.9
1.9
1.9
TCR
#
71
MIX
22
H
2.0
1.8
1.6
1.7
1.8
TCR
#
20
MIX
23
T
0.7
1.1
0.7
0.8
0.8
TCR
#
58
MIX
24
T
0.5
0.6
0.8
0.6
0.6
Stg.
1
#
1
BC
Avg
2.2
2.5
2.4
2.7
2.5
Stg.
1
#
2
BC
Avg
2.1
2.2
2.7
2.3
2.3
Stg.
1
#
3
MIX
Avg
1.6
1.7
1.7
1.9
1.7
Stg.
1
#
4
BC
Max
0.8
1.1
0.7
0.8
0.9
Stg.
1
#
5
NC
Avg
2.5
2.6
2.5
2.0
2.4
Stg.
1
#
6
NC
Avg
2.4
2.2
2.7
2.5
2.5
Stg.
1
#
7
MIX
Avg
1.4
2.0
1.7
2.0
1.8
Stg.
1
#
8
NC
Max
0.7
1.7
0.8
1.4
1.0
MIX
­
Mixing
Zone
TCR
­
Total
Coliform
Rule
E
­
Near
Entry
Point
NC
­
New
City
Source
Stg.
1
­
Stage
1
DBPR
A
­
Average
Residence
Time
BC
­
Big
City
Source
T
­
Representative
High
TTHM
H
­
Representative
High
HAA5
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
6
Table
J.
2
Grove
City
Distribution
System
 
Heterotrophic
Plate
Count
(
HPC)
Data
Sample
Site
ID
#
Source/
Plant
Stage
1
Type
SMP
Site
#
SMP
Type
HPC
(
cfu/
mL)

June
July
Aug.
Sept.
Mean
TCR
#
9
NC
1
E
12
8
34
12
17
TCR
#
11
NC
2
A
78
86
384
364
228
TCR
#
22
NC
3
A
35
62
147
92
84
TCR
#
3
NC
4
A
43
34
156
224
114
TCR
#
46
NC
5
H
34
76
97
89
74
TCR
#
5
NC
6
H
54
65
87
97
76
TCR
#
6
NC
7
H
35
43
64
45
47
TCR
#
78
NC
8
T
68
175
399
375
254
TCR
#
81
NC
9
T
151
273
164
354
235
TCR
#
39
NC
10
T
43
67
125
102
84
TCR
#
10
NC
11
T
156
278
169
359
240
TCR
#
1
BC
12
E
67
14
35
42
40
TCR
#
86
BC
13
A
43
34
156
224
114
TCR
#
21
BC
14
A
54
65
573
65
189
TCR
#
35
BC
15
A
56
72
202
147
119
TCR
#
13
BC
16
H
53
64
94
123
83
TCR
#
49
BC
17
H
50
34
113
63
65
TCR
#
65
BC
18
H
35
43
64
45
47
TCR
#
16
MIX
19
T
34
76
97
89
74
TCR
#
51
BC
20
T
69
43
37
43
48
TCR
#
72
MIX
21
T
54
65
573
65
189
TCR
#
71
MIX
22
H
66
53
153
53
81
TCR
#
20
MIX
23
T
70
212
356
332
242
TCR
#
58
MIX
24
T
233
214
456
546
362
Stg.
1
#
1
BC
Avg
56
42
345
276
180
Stg.
1
#
2
BC
Avg
82
136
146
246
152
Stg.
1
#
3
MIX
Avg
280
163
446
263
288
Stg.
1
#
4
BC
Max
140
215
557
615
382
Stg.
1
#
5
NC
Avg
50
42
223
522
209
Stg.
1
#
6
NC
Avg
53
42
84
72
63
Stg.
1
#
7
MIX
Avg
140
66
364
236
201
Stg.
1
#
8
NC
Max
196
45
653
425
330
MIX
­
Mixing
Zone
TCR
­
Total
Coliform
Rule
E
­
Near
Entry
Point
NC
­
New
City
Source
Stg.
1
­
Stage
1
DBPR
A
­
Average
Residence
Time
BC
­
Big
City
Source
T
­
Representative
High
TTHM
H
­
Representative
High
HAA5
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
7
4.
Summary
of
selected
SMP
sample
sites:

Present
the
rationale
for
the
selection
of
the
IDSE
sampling
sites,
as
well
as
a
schematic
showing
their
location
within
the
distribution
system.

Sampling
sites
were
chosen
to
represent
diverse
geographical
areas
of
the
distribution
system.
Each
site
is
shown
on
the
map
of
the
distribution
system
in
section
I.
6.
Residual
total
chlorine
(
Table
J.
1)
and
HPC
data
(
Table
J.
2)
were
considered
in
the
selection
of
SMP
monitoring
sites.

SMP
Site
#
1
 
Entry
point
to
the
distribution
system
for
New
City
supply.
This
site
is
located
where
the
first
group
of
customers
receives
water.

SMP
Site
#
2
 
Represents
average
residence
time
of
water
leaving
New
City.
Based
on
total
chlorine
monitoring
results
at
TCR
sample
sites,
we
identified
the
areas
within
the
system
where
total
chlorine
levels
dropped
by
approximately
50
percent
of
the
total
drop
in
residual
seen
in
the
area
supplied
by
New
City.
The
average
initial
concentration
(
at
SMP
#
1)
was
3.5
mg/
L.
The
average
residual
at
SMP
#
11
(
the
site
with
the
lowest
residual
and
solely
under
the
influence
of
New
City)
is
0.7
mg/
L.
Therefore,
the
average
drop
in
residual
across
the
system
is
approximately
2.8
mg/
L;
half
of
that
drop
is
1.4
mg/
L.
Sites
with
residual
concentrations
near
2.1
mg/
L
were
considered
to
be
approximate
average
residence
time
sites.
The
average
residual
at
this
site
is
2.5
mg/
L.
There
are
no
storage
facilities
between
the
entry
point
and
this
site.

SMP
Site
#
3
 
Represents
average
residence
time
of
water
received
from
New
City.
Water
at
this
site
has
an
average
total
chlorine
residual
of
2.3
mg/
L.
Based
on
the
rationale
presented
in
the
discussion
of
site
#
2,
this
site
was
determined
to
be
an
approximate
average
residence
time
site.

SMP
Site
#
4
 
Represents
average
residence
time
of
water
entering
from
New
City.
Water
at
this
site
has
an
average
total
chlorine
residual
of
2.5
mg/
L.
Based
on
the
rationale
presented
in
the
discussion
of
site
#
2,
this
site
was
determined
to
be
an
approximate
average
residence
time
site.

SMP
Site
#
5
 
Represents
high
HAA5
levels.
Sample
site
is
in
an
area
approaching
the
perimeter
of
the
distribution
system.
Water
in
this
area
is
primarily
from
the
New
City.
Total
chlorine
residual
at
this
site
ranges
between
1.7
and
2.1
mg/
L,
and
the
heterotrophic
plate
count
is
consistently
below
100
cfu
per
mL
year
round.

SMP
Site
#
6
 
Represents
high
HAA5
levels.
This
site
is
at
the
edge
of
the
mixing
zone
between
the
New
City
and
Big
City
influence
areas.
Total
chlorine
residual
levels
ranged
between
1.0
and
1.2
mg/
L
at
this
site,
and
the
heterotrophic
plate
count
never
exceeded
100
cfu
per
mL.

SMP
Site
#
7
 
Represents
high
HAA5
levels.
This
site
is
a
hose
bib
located
at
a
convenience
store.
Total
chlorine
residual
levels
ranged
between
1.6
and
1.8
mg/
L
at
this
site,
and
the
heterotrophic
plate
count
never
exceeded
100
cfu
per
mL.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
8
SMP
Site
#
8
 
Represents
high
TTHM
levels.
This
sampling
site
is
the
western
edge
of
the
city.
Total
chlorine
residuals
at
this
site
are
generally
very
low.

SMP
Site
#
9
 
Represents
high
TTHM
levels.
This
sampling
site
is
believed
to
receive
water
from
the
Pineville
Storage
tank
(
a
4
MG
ground
tank)
during
high
demand
periods
and
is
at
the
entrance
to
a
small
subdivision
cul­
de­
sac
in
the
Oakville
community.
Chlorine
residuals
at
this
site
are
generally
low.
The
sample
site
is
near
the
first
house
on
the
cul­
de­
sac
(
which
has
12
homes
total).

SMP
Site
#
10
 
Represents
high
TTHM
levels.
This
site
is
located
upstream
of
the
Stage
1
DBPR
monitoring
site
#
7.
Both
are
used
for
routine
Total
Coliform
Rule
and
chlorine
residual
monitoring.
We
have
over
7
years
of
data
from
this
site.
This
site
is
located
near
the
predicted
edge
of
the
mixing
zone
where
chlorine
residual
measurements
indicate
there
may
be
a
hydraulic
dead
end.
Water
at
this
site
is
generally
from
the
New
City
supply,
although
specific
conductivity
data
show
that
some
mixed
zone
water
may
also
influence
this
site.

SMP
Site
#
11
 
Represents
high
TTHM
levels.
This
site
has
been
problematic
in
the
past
due
to
positive
total
coliform
test
results,
very
low
total
chlorine
residuals,
high
heterotrophic
plate
count
results,
and
odor
complaints.
A
4­
inch
blow­
off
was
installed
downstream
of
this
site,
but
it
continues
to
have
periodic
poor
water
quality.
Water
in
this
area
is
from
the
New
City
supply.

SMP
Site
#
12
 
Entry
point
to
the
distribution
system
for
the
Big
City
supply.
This
site
is
located
near
the
first
group
of
customers
that
receive
water
from
the
Big
City
supply.

SMP
Site
#
13
 
Represents
average
residence
time
of
water
entering
from
Big
City.
Based
on
total
chlorine
monitoring
results
at
TCR
sample
sites,
we
identified
the
areas
within
the
system
where
total
chlorine
levels
dropped
by
approximately
50
percent
of
the
total
drop
in
residual
seen
in
the
area
supplied
by
Big
City.
The
average
initial
concentration
(
at
SMP
#
1)
was
3.3
mg/
L.
The
average
residual
at
site
#
24
(
the
site
with
the
lowest
residual
and
solely
under
the
influence
of
New
City)
is
0.6
mg/
L.
Therefore,
the
average
drop
in
residual
across
the
system
is
approximately
2.7
mg/
L;
half
of
that
drop
is
1.3
to
1.4
mg/
L.
Sites
with
residual
concentrations
near
2.0
mg/
L
were
considered
to
be
approximate
average
residence
time
sites.
The
average
total
chlorine
residual
at
this
site
is
2.2
SMP
Site
#
14
 
Represents
average
residence
time
of
water
entering
from
Big
City.
Water
at
this
site
has
an
average
total
chlorine
residual
of
1.9
mg/
L.
Based
on
the
rationale
presented
in
the
discussion
of
site
#
13,
this
site
was
determined
to
be
an
approximate
average
residence
time
site.

SMP
Site
#
15
 
Represents
average
residence
time
for
the
Big
City
water
supply.
This
sampling
site
is
in
the
southern
edge
of
Cedarville
subdivision.
Water
at
this
site
has
an
average
total
chlorine
residual
of
2.2
mg/
L.
Based
on
the
rationale
presented
in
the
discussion
of
site
#
13,
this
site
was
determined
to
be
an
approximate
average
residence
time
site.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
9
SMP
Site
#
16
 
Represents
high
HAA5
levels.
Our
Stage
1
DBPR
results
indicate
the
high
HAA5
concentrations
move
around
our
system
depending
on
the
season
and
proportion
of
water
supplies
from
New
City
and
Big
City,
especially
in
the
areas
served
by
the
Big
City.

SMP
Site
#
17
 
Represents
high
HAA5
levels
for
the
Big
City
supply.
At
this
site,
the
water
age
is
greater
than
average
(
evidenced
by
average
total
chlorine
residual
of
1.5),
the
total
chlorine
residual
was
never
below
1.8
mg/
L
and
the
heterotrophic
count
plate
is
usually
low
(
below
100
with
one
exception
in
August).

SMP
Site
#
18
 
Represents
high
HAA5
levels
for
the
Big
City
supply.
At
this
site,
the
water
age
is
approximately
equal
to
the
system
average
(
evidenced
by
average
total
chlorine
residual
of
2.1),
the
total
chlorine
residual
was
never
below
1.9
mg/
L
and
the
heterotrophic
count
plate
is
usually
low
(
below
100).

SMP
Site
#
19
 
Represents
high
TTHM
levels.
This
sample
site
is
located
in
a
zone
of
the
distribution
system
that
has
been
recently
developed.
This
connection
is
located
downstream
from
a
chlorine
booster
station.
Total
chlorine
residuals
are
normally
in
the
2.5
to
2.9
mg/
L
range.
Water
in
this
area
is
generally
a
mix
of
water
from
the
New
City
and
Big
City
supplies.

SMP
Site
#
20
 
Represents
high
TTHM
levels.
This
site
is
downstream
from
the
Jackson
Storage
Tank
in
Cypressville,
a
1.5
million
gallon
elevated
storage
tank.
There
are
often
low
chlorine
residuals
in
the
areas
downstream
of
this
tank.

SMP
Site
#
21
 
Represents
high
TTHM
levels.
This
sampling
site
is
in
the
mixed
zone
before
the
last
group
of
connections
near
the
end
of
the
distribution
system.
This
area
receives
water
from
the
Cherry
Hill
Storage
Tank
and
water
that
bypasses
the
tank.
Water
from
this
area
can
vary
greatly
in
the
percentages
of
New
City
and
Big
City
water.

SMP
Site
#
22
 
Represents
high
HAA5
levels.
At
this
site,
the
water
age
is
believed
to
be
greater
than
average
because
it
is
within
the
mixing
zone,
but
the
total
chlorine
residual
is
never
below
1.6
mg/
L
and
the
heterotrophic
count
plate
is
usually
low
(
below
100
cfu/
mL
with
one
exception
in
August).

SMP
Site
#
23
 
Represents
high
TTHM
levels.
This
sampling
site
is
in
the
mixed
zone.
Total
chlorine
residuals
range
from
0.7
to
1.1
mg/
L
which
is
well
below
the
system
average.
This
area
receives
water
from
the
Pineville
ground
storage
tank.

SMP
Site
#
24
 
Represents
high
TTHM
levels.
This
sampling
site
is
in
the
mixed
zone.
It
has
total
chlorine
residuals
that
range
from
0.5
to
0.8
mg/
L
which
is
well
below
the
system
average.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
10
5.
SMP
Sample
Schedule:

Because
the
quarterly
Stage
1
DBPR
monitoring
is
the
only
DBP
monitoring
that
has
been
performed
in
the
Grove
City
system,
historic
DBP
data
is
available
for
only
the
months
of
January,
April,
July,
and
October.
July
has
regularly
had
the
highest
DBP
levels,
but
no
DBP
data
is
available
for
the
other
summer
months.
As
a
result,
we
also
reviewed
finished
water
temperature
in
two
years
of
TCR
sampling
records
and
determined
our
peak
month
for
distribution
system
water
temperature
is
August.
But,
we
also
found
that
July's
average
distribution
system
water
temperature
for
the
two
years
reviewed
was
only
0.5
º
C
less.
Based
on
the
historic
DBP
data
and
minimal
difference
in
average
water
temperature,
we
concluded
July
is
the
controlling
month
for
the
Elm
City
distribution
system.
The
following
table
summarizes
our
planned
SMP
sample
dates
and
is
based
on
collection
of
our
samples
on
the
second
Monday
of
the
month.

Proposed
SMP
Sample
Schedule
Planned
Sample
Date
November
8,
2005
January
10,
2006
March
14,
2006
May
9,
2006
July
11,
2006
September
12,
2006
Dual
sample
sets
will
be
collected
from
each
of
the
24
SMP
sample
sites
on
or
close
to
the
listed
dates
and
analyzed
for
TTHM
and
HAA5
by
a
State­
certified
laboratory.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
11
Poplarville
MIXING
ZONE
Elevated
Storage
Tank
Ground
storage
tank
Pump
station
Chlorine
Booster
Station
8
7
6
5
4
3
2
1
11
10
4
6
3
2
1
12
21
20
19
16
22
14
13
Stage
1
DBPR
site
TCR
/
Selected
SMP
site
Appleville
Weeping
Willow
Oakville
Pineville
Cedarville
Cypressville
Downtown
Industrial
Park
PS2
CB2
PS3
CB1
PS1
New
City
Purchased
Water
Entry
Point
Big
City
Purchased
Water
Entry
Point
Grove
City
Water
Distribution
System
18
17
15
23
24
5
9
8
7
6.
Map
of
the
distribution
system
showing
major
transmission
mains,
numbered
Stage
1
DBPR
compliance
sites,
and
numbered
SMP
sample
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
12
II.
SMP
RESULTS
1.
Introduction:

The
SMP
was
conducted
between
November
2005
and
September
2006.
The
following
table
summarizes
our
planned
SMP
sample
dates,
the
actual
dates
when
samples
were
collected,
and
the
reasons
for
deviations
from
the
plan.

Actual
SMP
Sample
Schedule
Planned
Sample
Date
Actual
Sample
Date
Explanation
November
8,
2005
November
8,
2005
On
schedule
January
10,
2006
January
10,
2006
On
schedule
March
14,
2006
March
14,
2006
On
schedule
May
9,
2006
May
9,
2006
On
schedule
July
11,
2006
July
11,
2006
On
schedule
September
12,
2006
September
14,
2006
Flooding
closed
many
of
the
roads
in
Grove
City,
making
many
sample
sites
inaccesible
until
September
14.

2.
Summary
of
IDSE
SMP
data
and
Stage
1
DBPR
compliance
data:

All
DBP
results
from
the
SMP
and
concurrent
Stage
1
DBPR
compliance
monitoring
are
presented
in
this
section.
The
first
table
presents
the
DBP
results
for
the
SMP
sample
sites,
organized
by
plant,
then
in
order
of
highest
to
lowest
TTHM
LRAA.
The
second
table
presents
the
DBP
results
for
the
Stage
1
DBPR
compliance
sample
sites
for
the
period
from
November
2005
to
August
2006.
Sites
proposed
as
Stage
2B
compliance
monitoring
locations
are
shaded
within
the
tables.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
13
Grove
City
 
IDSE
SMP
Monitoring
Results
SMP
Site
#
Site
Type
TTHM
(
ug/
L)
HAA5
(
ug/
L)

Data1
LRAA
Data1
LRAA
1
entry
point
36,
42,
30,
25,
38,
28
33
50,
44,
43,
47,
48,
38
45
12
entry
point
30,
32,
39,
40,
32,
28
29
31,
29,
38,
48,
51,
45
43
13
average
residence
time
42,
34,
52,
57,
62,
51
50
23,
56,
40,
52,
40,
28
40
2
average
residence
time
54,
39,
42,
56,
60,
42
49
22,
29,
36,
40,
41,
30
33
4
average
residence
time
51,
42,
50,
39,
50,
42
47
19,
26,
28,
31,
26,
22
25
14
average
residence
time
47,
40,
52,
43,
51,
41
46
14,
20,
21,
23,
29,
19
21
15
average
residence
time
40,
45,
45,
48,
52,
46
46
41,
32,
45,
40,
35,
43
39
3
average
residence
time
42,
39,
53,
43,
49,
40
44
20,
25,
25,
29,
27,
19
24
6
high
HAA5
36,
41,
43,
39
49,
45
42
60,
58,
68,
57,
68,
55
61
16
high
HAA5
52,
35,
46,
42,
50,
38
44
56,
44,
65,
50,
50,
58
54
17
high
HAA5
50,
33,
44,
40,
48,
36
42
53,
42,
64,
48,
49,
55
52
7
high
HAA5
35,
30,
42,
44,
44,
25
37
37,
43,
55,
57,
50,
42
47
5
high
HAA5
33,
29,
41,
42,
44,
22
35
36,
43,
52,
51,
48,
38
45
18
high
HAA5
35,
31,
47,
38,
49,
30
39
37,
42,
48,
50,
41,
35
42
22
high
HAA5
35,
29,
47,
37,
47,
27
37
36,
40,
46,
48,
40,
34
41
11
high
TTHM
68,
59,
78,
76,
75,
65
70
42,
39,
47,
46,
40,
49
44
8
high
TTHM
62,
60,
65,
71,
74,
72
67
42,
40,
33,
38,
46,
30
38
10
high
TTHM
68,
62,
54,
65,
72,
70
65
39,
45,
28,
33,
40,
32
36
23
high
TTHM
67,
59,
58,
49,
71,
75
63
32,
35,
27,
30,
39,
29
32
21
high
TTHM
69,
56,
72,
59,
71,
55
63
19,
25,
39,
29,
21,
38
29
20
high
TTHM
65,
61,
54,
50,
69,
71
62
37,
41,
29,
30,
41,
29
35
9
high
TTHM
51,
56,
69,
58,
67,
52
59
31,
38,
37,40,
32,
45
37
24
high
TTHM
50,
51,
55,
53,
62,
65
56
37,
39,
29,
28,
39,
27
33
19
high
TTHM
56,
50,
55,
51,
61,
45
53
42,
30,
43,
38,
34,
42
38
1Data
obtained
from
sampling
every
60
days
are
listed
in
order
for
November,
January,
March,
May,
July,
and
September
(
as
required
for
a
surface
water
supply
$
10,000).
Note:
Bold
text
and
shading
identifies
proposed
Stage
2
DBPR
compliance
sites.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
14
Grove
City
 
Stage
1
DBPR
Compliance
Monitoring
Results
Stage
1
Site
#
Site
Type
TTHM
(
ug/
L)
HAA5
(
ug/
L)

Data1
LRAA
Data1
LRAA
Stg.
1
#
4
Maximum
64,
68,
83,
74
72
21,
25,
26,
28
25
Stg.
1
#
8
Maximum
61,
48,
56,
71
59
19,
22,
37,
30
27
Stg.
1
#
2
Average
38,
42,
52,
62
49
50,
62,
64,
65
59
Stg.
1
#
1
Average
45,
34,
56,
62
49
24,
32,
43,
45
36
Stg.
1
#
6
Average
47,
49,
39,
52
47
22,
30,
39,
41
33
Stg.
1
#
3
Average
36,
42,
45,
45
42
47,
50,
55,
56
52
Stg.
1
#
5
Average
44,
20,
62,
42
42
34,
45,
33,
41
38
Stg.
1
#
7
Average
41,
22,
50,
59
43
32,
46,
59,
52
47
1Data
listed
in
order
for
October,
January,
April,
and
July
quarterly
sampling.
Note:
Bold
text
and
shading
identifies
proposed
Stage
2B
compliance
sites.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
15
III.
PROPOSED
STAGE
2B
COMPLIANCE
MONITORING
SITES
1.
Site
Summary:

A
total
of
12
Stage
2B
compliance
monitoring
sites
were
selected
from
the
Stage
1
DBPR
and
SMP
sites,
as
shown
in
the
previous
tables
and
as
summarized
in
the
following
table.

Stage
2B
Proposed
Compliance
Monitoring
Sites
Stage
2B
Compliance
Sites
Previous
Sample
Site
ID
Site
#
Type
1
Average
Stg.
1
#
2
2
Average
Stg.
1
#
3
3
Average
Stg.
1
#
1
4
High
HAA5
SMP
#
6
5
High
HAA5
SMP
#
16
6
High
HAA5
SMP
#
17
7
High
TTHM
Stg.
1
#
4
8
High
TTHM
SMP
#
11
9
High
TTHM
SMP
#
8
10
High
TTHM
SMP
#
10
11
High
TTHM
SMP
#
23
12
High
TTHM
SMP
#
20
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
16
2.
Justification
of
Site
Selections:

The
reasons
for
the
selection
of
the
12
sites
for
Stage
2B
monitoring
are:

1.
Average
Residence
Time
Sites
 
The
Stage
2
DBPR
required
us
to
select
three
average
residence
time
sites
from
among
our
existing
Stage
1
DBPR
monitoring
sites.
The
sites
were
required
to
be
selected
based
on
alternating
highest
TTHM
LRAA
and
HAA5
LRAA.
Because
we
have
three
average
residence
time
sites,
we
ultimately
ended
up
selecting
two
based
on
highest
TTHM
LRAA
and
one
based
on
highest
HAA5
LRAA.
Stage
1
DBPR
average
residence
time
sites
#
2
and
#
1
had
the
highest
TTHM
LRAA
among
Stage
1
DBPR
average
residence
time
sites.
Stage
1
DBPR
site
#
3
had
the
highest
HAA5
LRAA
among
the
Stage
1
average
residence
time
sites.

2.
Representative
High
HAA5
Site
 
The
three
highest
HAA5
LRAA
values
occur
at
SMP
site
#
6
and
#
16,
and
#
17.
Therefore,
these
three
sites
were
designated
as
Stage
2B
sites
(
numbers
4,
5,
and
6).

3.
Representative
High
TTHM
Sites
 
The
six
highest
TTHM
LRAA
values
occur
at
SMP
Site
#
11,
#
8,
#
10,
#
23,
and
#
20,
and
Stage
1
DBPR
Site
#
4.
Therefore,
these
six
sites
were
designated
as
Stage
2B
sites.
SMP
site
#
20
and
#
21
actually
had
the
same
TTHM
LRAA,
but
site
#
20
provided
better
geographic
coverage
and
was
selected
as
a
proposed
Stage
2B
monitoring
site.

3.
Proposed
Stage
2B
Compliance
Monitoring
Schedule:

Stage
2B
compliance
monitoring
will
be
scheduled
for
January,
April,
July,
and
October,
the
same
as
Stage
1
DBPR
and
Stage
2A
DBPR
sampling,
for
consistency
and
because
the
difference
in
distribution
system
water
temperature
between
July
and
August
is
minimal
(
average
0.5
º
C
higher
in
August,
based
on
a
review
of
2
years
of
TCR
sampling
records).
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
17
Poplarville
MIXING
ZONE
Elevated
Storage
Tank
Ground
storage
tank
Pump
station
Chlorine
Booster
Station
Appleville
Weeping
Willow
Oakville
Pineville
Cedarville
Cypressville
Downtown
Industrial
Park
PS2
CB2
PS3
CB1
PS1
Grove
City
Stage
2B
DBPR
Compliance
Sample
Sites
Stage
2B
Representative
High
TTHM
Stage
2B
Representative
High
HAA5
Stage
2B
Average
Residence
Time
#

#
#

New
City
Purchased
Water
Entry
Point
Big
City
Purchased
Water
Entry
Point
1
4
2
3
6
5
7
10
11
12
8
9
4.
Map
of
Proposed
Stage
2B
Compliance
Monitoring
Sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
J­
18
This
page
intentionally
left
blank.
Appendix
K
IDSE
System
Specific
Study
Using
a
Hydraulic
Model
This
appendix
is
provided
as
an
example
IDSE
report
for
producing
surface
water
systems
serving
least
10,000
people
and
opting
to
complete
a
System
Specific
Study
(
SSS)
using
a
water
distribution
system
model.

Chapter
3
presents
detailed
guidance
on
the
requirements
for
performing
an
SSS
with
a
water
distribution
system
model.
Chapter
5
presents
the
detailed
SMP
requirements
for
these
systems.
Chapter
3
also
provides
guidance
on
selecting
SMP
sites
and
Stage
2B
compliance
monitoring
sites
based
on
SSS
data,
as
well
as
IDSE
reporting
requirements.
The
application
of
the
basic
guidance
on
SMP
site
selection
and
Stage
2B
compliance
monitoring
site
selection
is
shown
in
this
example,
along
with
several
instances
of
the
use
of
best
professional
judgement
being
applied.

The
italicized
text
within
the
appendix
consists
of
comments
and
explanations
and
is
not
intended
to
represent
the
recommended
content
of
an
actual
IDSE
Report.
This
page
intentionally
left
blank.
Initial
Distribution
System
Evaluation
Report
for
Big
City
PWSID
Number:
US1111111
Address:
1234
Main
Street
Big
City,
US
99999
Contact
Person:
Mr.
John
Smith,
P.
E.

Phone
Number:
123­
555­
0000
Fax
Number:
123­
555­
0001
Email
Address:
jsmith@
ci.
bigcity.
us
System
Type:
Community,
surface
water
Population
Served:
55,000
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
1
1.
System
Description:

This
section
of
the
report
includes
a
summary
of
typical
system
operating
characteristics
(
and
how
they
change
on
a
seasonal
basis
if
appropriate)
explaining
how
sources
are
used
to
meet
system
demands,
where
high
water
age
is
expected
to
occur,
and
any
special
aspects
of
operation
that
could
affect
DBP
concentrations
in
the
distribution
system.
Information
about
water
treatment
processes
and
source
water
quality
data
should
also
be
part
of
this
section,
including
a
description
of
water
treatment,
actual
residence
times
within
the
water
treatment
plant
and
the
distribution
system.

General
system
characteristics:
Service
area:
Big
City
plus
surrounding
suburban
areas
Production:
Annual
average
daily
demand
7
MGD
Source
Water
Information:
Adams
Reservoir
(
surface
water)
water
quality:
pH:
from
7.0
to
8.0
Alkalinity:
from
62
to
88
mg/
L
as
CaCO3
TOC:
from
3.2
to
6.8
mg/
L
as
C
Lincoln
River
(
surface
water)
water
quality:
pH:
from
6.8
to
7.9
Alkalinity:
from
77
to
94
mg/
L
as
CaCO3
TOC:
from
1.6
to
4.4
mg/
L
as
C
Entry
points
and
service
areas
under
the
influence
of
each
entry
point:
(
Entry
points
should
be
tied
to
source(
s)
and
typical
flows
noted)

Entry
points:
Adams
Plant
 
serves
the
northern
half
of
the
city
Lincoln
Plant
 
serves
the
southern
half
of
the
city
Treatment
Provided:
Adams
Plant
is
a
6
MGD
plant
located
on
the
northern
edge
of
the
city.
It
draws
water
from
Adams
Reservoir.
The
plant
utilizes
coagulation
(
with
ferric
chloride),
flocculation,
sedimentation,
and
dual
media
filters
(
filter
loading
rates
are
approximately
4
gpm/
sf).

Lincoln
Plant
is
an
8
MGD
plant
located
in
the
southern
part
of
the
system
and
draws
water
from
Lincoln
River.
The
treatment
process
is
identical
to
that
of
the
Adams
Plant,
except
that
the
Lincoln
Plant
also
includes
GAC
filters
following
dual
media
filtration
to
enhance
TOC
removal.
The
Lincoln
River
is
prone
to
rapid
changes
in
TOC,
and
the
GAC
was
installed
as
an
extra
barrier
to
prevent
significant
DBP
formation
in
the
distribution
system.

Primary
and
residual
disinfection:
Chlorine/
chloramines
at
both
plants.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
2
Description
of
distribution
system:

Distribution
system
(
estimated
length
of
lines
and
range
of
diameter):
About
300
miles,
4"
­
36"
Lined
and
unlined
cast
iron
pipe,
ductile
iron
pipe,
and
plastic
pipe
4
storage
tanks
of
9
MG
total
capacity
1
ground
tank
4
MG
capacity
2
elevated
tanks
each
with
2
MG
capacity
1
elevated
tank
with
1
MG
capacity
The
average
residence
time
of
water
in
the
distribution
system
is
approximately
two
days.

Pump
stations:
A
pump
station
is
located
at
the
north
tank
(
4
MG
ground
storage
tank).
This
pump
is
primarily
used
during
peak
demands
and
low
pressure
situations.
The
pump
is
timed
to
turn
on
in
the
morning
and
evening
during
peak
demand,
and
when
the
pressure
drops
below
40
psi
at
a
point
downstream
of
the
pump
station.

Booster
chloramination
facilities:
Booster
Facility
A
is
located
in
the
northwestern
part
of
the
city.
This
facility
is
occasionally
used
during
the
summer
when
total
chlorine
residuals
at
remote
locations
downstream
of
the
booster
facility
cannot
be
maintained.

Booster
Facility
B
is
located
in
the
southeastern
part
of
the
city,
where
total
chloramine
residuals
have
historically
been
low.

A
schematic
of
the
distribution
system
is
presented
in
the
following
section.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
3
Booster
chloramination
facility
Ground
storage
tank
Elevated
storage
tank
MIXING
ZONE
Adams
WTP
Lincoln
WTP
North
Tank
(
w/
pump
station)

South
Tank
West
Tank
Central
Tank
Booster
Station
B
Booster
Station
A
2.
Schematic
of
the
distribution
system:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
4
3.
Summary
of
SSS
requirements:

Big
City
has
extensive
experience
with
water
distribution
system
modeling.
To
select
Stage
2B
compliance
monitoring
sites,
the
city
has
performed
a
System
Specific
Study
(
SSS)
based
on
its
water
distribution
system
model,
data
from
one
round
of
new
DBP
sampling,
and
data
from
Stage
1
DBPR
compliance
monitoring.

To
confirm
model
results,
we
conducted
one
round
of
DBP
sampling
at
sites
equivalent
to
those
that
would
be
selected
under
the
SMP
requirements
for
large,
subpart
H
systems.
A
summary
of
these
requirements
is
presented
in
the
following
table.
The
methodology
by
which
these
sites
were
chosen
is
presented
in
section
5.

Additional
DBP
Sampling
Site
Criteria1
Site
Criteria
Number
of
Sample
Sites
Adams
WTP
Influence
Zone
Lincoln
WTP
Influence
Zone
Near
entry
to
the
distribution
system
2
2
Average
residence
time
2
2
Representative
of
high
TTHM
2
2
Representative
of
high
HAA5
2
2
1
These
sites
were
allocated
based
on
SMP
requirements
for
a
system
of
our
size
and
source
water
type
and
practicing
similar
disinfection
methods.

4.
Description
of
Hydraulic
Model
The
hydraulic
model
for
Big
City
includes
all
8­
inch
and
larger
pipes
and
also
includes
6­
inch
pipes
for
the
remote
areas
of
the
distribution
system.
Approximately
60
percent
of
the
total
pipe
length
in
the
distribution
system
is
included
in
the
model.
The
open/
closed
status
of
all
four
storage
tanks
and
the
on/
off
status
of
the
pump
station
at
the
North
Tank
have
been
modeled.
There
are
two
control
valves
in
the
distribution
system,
but
these
do
not
significantly
affect
the
water
flow
through
the
distribution
system.
Therefore,
these
control
valves
have
not
been
modeled.

Water
demand
has
been
assigned
to
approximately
60
percent
of
the
nodes
in
the
model.
In
areas
where
there
are
no
water
users
at
the
dead­
end
of
a
pipe
segment,
a
very
small
nominal
demand
was
assigned
to
the
end
nodes
so
that
water
ages
at
the
dead
ends
could
be
calculated
by
the
modeling
software.
Summer
and
winter
average
demand
data
were
available
for
residential
customers
and
large
commercial
and
industrial
customers.
The
estimated
water
loss
in
the
system
is
about
10
percent
and
this
was
accounted
for
in
the
model.
Based
on
the
master
meter
flows,
tank
levels,
and
customer
meter
readings,
a
diurnal
(
24­
hour)
demand
pattern
was
derived
and
was
applied
to
the
residential,
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
5
commercial,
and
industrial
customers.
The
inclusion
of
diurnal
demand
patterns
allows
the
hydraulic
model
to
be
run
in
the
extended
period
simulation
(
EPS)
mode.

A
major
calibration
effort
was
performed
when
the
model
was
developed
in
1998.
At
that
time
the
model
was
calibrated
for
average
summer
and
maximum
day
conditions.
Since
the
last
calibration,
no
significant
changes
have
been
made
to
the
distribution
system
that
could
change
the
system
hydraulics.
The
calibration
program
included
extensive
C­
factor
tests
conducted
over
the
previous
10
years
and
comparisons
of
modeled
and
measured
pressures
throughout
the
system.
The
model
predicted
pressures
were
within
±
3
psi
of
the
field
measured
pressures
at
70
percent
of
the
readings.
This
is
consistent
with
calibration
guidelines
for
hydraulic
models
to
be
used
for
water
quality
purposes
(
Walski,
et
al.,
"
Perspectives
in
Calibration,"
Current
Methods,
1:
1:
21,
Haested
Press,
2001).

5.
Summary
of
the
SSS
methodology:

Summarize
the
methodology
used
to
conduct
the
SSS,
including
the
rationale
for
the
selection
of
sites
equivalent
to
the
sample
sites
required
for
the
Standard
Monitoring
Program
(
SMP).

The
hydraulic
model
was
applied
in
a
variety
of
ways
to
understand
the
flow
of
water
through
the
distribution
system
and
guide
the
selection
of
monitoring
sites
that
reflected
the
selection
criteria
outlined
in
Chapter
3
of
the
IDSE
guidance
manual.
For
this
SSS,
16
sites
were
selected
that
meet
the
criteria
required
for
the
SMP
of
a
system
of
a
similar
size
and
source
water
type
providing
similar
disinfection
(
see
section
3).

The
model
was
run
in
the
extended
period
simulation
(
EPS)
mode
under
average
summer
conditions
for
14
days,
and
showed
a
consistent,
repeating
pattern
of
water
age
at
all
nodes
after
approximately
10
days.
This
indicates
the
maximum
residence
time
in
the
distribution
system
under
average
summer
conditions
is
approximately
10
days.
The
water
age
option
was
used
in
the
model
to
obtain
residence
time
throughout
the
distribution
system.
In
addition
to
residence
time
calculations,
the
model
was
used
to
define
influence
zones
of
the
two
source
waters.
The
source
tracing
option
was
used
in
the
model
to
determine
the
average
contribution
of
the
two
water
sources
to
each
node
in
the
model.

Three
zones
were
defined
based
on
the
two
water
sources:

°
The
area
served
primarily
by
the
Adams
WTP
°
The
area
served
primarily
by
the
Lincoln
WTP
°
The
area
that
generally
received
water
from
both
treatment
plants
over
the
course
of
the
day,
either
as
a
mixture
or
on
an
alternating
basis
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
6
Because
the
Stage
1
DBPR
compliance
data
indicates
that
DBP
levels
are
highest
in
the
Big
City
distribution
system
during
the
summer
months,
average
day
demands
for
the
summer
were
used
to
determine
residence
times
and
mixing
zones.
Average
day
demands
during
winter
conditions
were
also
examined
and
the
mixing
zone
was
found
to
be
very
similar
to
the
summer
conditions.

The
residence
time
data
obtained
from
the
model
for
the
summer
conditions
were
compared
with
the
total
chlorine
residual
data
at
the
TCR
monitoring
sites
for
May
and
August
(
Table
K.
1).
In
general,
there
is
a
direct
correlation
between
model­
predicted
residence
times
and
total
chlorine
residuals.
Sites
on
the
periphery
of
the
distribution
system
have
longer
residence
times
and
lower
total
chlorine
residuals,
except
for
areas
where
booster
chloramination
is
used.
Sites
which
are
under
the
influence
of
the
booster
facilities
maintain
relatively
high
total
chlorine
residuals.
However,
these
sites
also
have
high
residence
times.
Table
K.
1
also
summarizes
model­
predicted
residence
times
at
each
of
the
TCR
monitoring
sites.

The
residence
times
from
the
model
were
used
to
select
16
of
the
20
TCR
monitoring
sites
for
DBP
monitoring.
These
sites
are
described
in
further
detail
in
the
following
section.
After
the
selection
of
16
sites,
one
round
of
DBP
dual
samples
was
taken
at
these
sites
during
August,
which
is
the
month
of
historically
high
DBP
levels.
The
residence
time
data,
Stage
1
DBPR
compliance
data
(
Table
K.
2),
and
DBP
data
from
this
new
round
of
sampling
were
then
used
to
select
Stage
2B
compliance
monitoring
sites.

Available
Data:

Report
all
data
that
helped
in
site
selection.
If
you
have
bromide,
TOC,
and
or
HPC
data,
these
may
be
helpful
for
justifying
Stage
2B
site
selection.

Total
chlorine
residual
data
for
the
months
of
February,
May,
August,
and
November,
and
residence
time
data
for
summer
demand
conditions
obtained
from
the
water
distribution
system
model,
at
TCR
monitoring
sites
is
presented
in
Table
K.
1.
Quarterly
Stage
1
DBPR
compliance
monitoring
data
is
presented
in
Table
K.
2.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
7
Table
K.
1
Big
City
Distribution
System
 
Total
Chlorine
Residual
at
TCR
Monitoring
Sites
Monitoring
Site
Free
Chlorine
Residual
(
mg/
L)
Residence
Time
During
Summer
Demand
Conditions
(
days)

Nov.
2004
Feb.
2005
May
2005
Aug.
2005
Residence
Time
TCR
#
1
3.2
3.4
3.5
3.6
0.1
TCR
#
2
3.0
3.2
3.3
3.4
0.2
TCR
#
3
2.4
2.3
1.9
1.8
4.1
TCR
#
4
2.3
2.5
1.8
2.0
3.9
TCR
#
5
3.0
2.9
2.6
2.5
2.1
TCR
#
6
2.9
3.0
2.7
2.4
1.8
TCR
#
7*
2.9
3.1
1.8
2.0
5.5
TCR
#
8
1.8
1.4
1.1
1.0
6.6
TCR
#
9
3.3
3.4
3.4
3.5
0.1
TCR
#
10
3.4
3.3
3.5
3.4
0.1
TCR
#
11
2.5
2.6
2.0
1.8
1.9
TCR
#
12
2.7
2.4
1.9
1.7
2.2
TCR
#
13
2.5
2.2
1.7
1.9
3.2
TCR
#
14
2.4
2.2
2.0
1.8
4.1
TCR
#
15
1.4
1.5
1.2
1.3
6.7
TCR
#
16
1.6
1.6
1.3
1.1
7.0
TCR
#
17
1.9
2.2
2.0
1.8
3.4
TCR
#
18
2.6
2.4
2.6
2.5
1.3
TCR
#
19
3.0
3.1
1.9
2.2
5.3
TCR
#
20
2.0
1.9
1.5
1.6
4.4
Note:
Site
7
is
located
downstream
of
Booster
Station
A.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
8
Table
K.
2
Big
City
Distribution
System
 
Stage
1
DBPR
Monitoring
Results
Monitoring
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Last
4
Quarters
Data1
Aug.
2005
LRAA
Last
4
Quarters
Data1
Aug.
2005
LRAA
Adams
Plant
average
residence
time
Site
Number
1
45,
34,
56,
62
49
24,
32,
43,
45
36
Adams
Plant
average
residence
time
Site
Number
2
32,
34,
48,
67
45
42,
47,
55,
56
50
Adams
Plant
average
residence
time
Site
Number
3
36,
42,
45,
45
42
50,
62,
67,
68
62
Adams
Plant
maximum
residence
time
Site
Number
4
64,
68,
83,
74
72
21,
25,
26,
28
25
Lincoln
Plant
average
residence
time
Site
Number
5
44,
20,
62,
42
42
34,
45,
33,
41
38
Lincoln
Plant
average
residence
time
Site
Number
6
46,
49,
39,
50
46
22,
30,
39,
41
33
Lincoln
Plant
average
residence
time
Site
Number
7
41,
22,
50,
59
43
4,
46,
64,
58
54
Lincoln
Plant
maximum
residence
time
Site
Number
8
73,
50,
67,
58
62
19,
22,
37,
30
27
1
Data
listed
in
order
for
November
2004
and
February,
May,
and
August
2005
quarterly
sampling.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
9
6.
Description
of
SSS
monitoring
sites:

Present
the
rationale
for
selection
of
the
SSS
monitoring
sites,
as
well
as
a
schematic
showing
their
location
within
the
distribution
system.

SSS
monitoring
sites
were
selected
based
on
modeling
results
and
available
total
chlorine
residual
data.
The
sites
represent
diverse
geographical
areas
of
the
distribution
system
and
are
shown
on
the
map
of
the
distribution
system
in
section
7.

Sites
#
1
and
#
2
represent
the
entry
point
to
the
distribution
system
from
Adams
Plant.
The
residence
time
at
these
sites
is
about
2
to
4
hours.

Sites
#
3
and
#
4
are
representative
of
predicted
high
HAA5
concentrations
in
the
zone
served
by
the
Adams
WTP.
These
sites
are
located
on
6­
inch
dead­
end
lines
near
the
extremities
of
the
system.
As
a
result,
travel
time
(
and
thus
water
age)
to
these
sites
is
long,
approximately
4
days,
based
on
the
water
age
modeling.
However,
the
modeling
indicates
that
these
sites
are
always
fed
directly
from
the
treatment
plant
(
the
water
does
not
go
through
a
storage
tank)
and
routine
sampling
has
shown
that
there
are
adequate
chlorine
residuals
at
these
sites.
As
a
result,
biodegradation
is
not
expected
to
occur,
and
high
HAA5
concentrations
are
expected.

Sites
#
5
and
#
6
were
selected
to
represent
average
conditions
in
the
zone
fed
by
Adams
WTP.
Monitoring
results
indicated
an
average
total
chlorine
residual
at
these
sites
of
2.8
mg/
L
during
the
summer.
Modeling
shows
that
typical
water
age
at
these
sites
is
approximately
2
days.

Site
#
7
was
selected
to
represent
high
TTHM
levels
in
the
Adams
WTP
zone.
This
site
is
downstream
of
the
Chlorine
Booster
Station
A;
thus,
the
chlorine
residuals
are
relatively
high.
The
model
indicated
that
the
water
age
is
high
(
around
5
days).

Site
#
8
is
representative
of
high
TTHM
levels
in
the
mixing
zone
and
is
counted
as
one
of
the
eight
sites
required
for
the
Adams
WTP.
Modeling
shows
that
water
age
at
this
site
is
generally
high
(>
6
days)
throughout
the
day,
representing
water
that
has
traveled
a
significant
distance
and
that
has
usually
been
through
one
of
the
storage
tanks.

Sites
#
9
and
#
10
represent
the
entry
point
to
the
distribution
system
from
the
Lincoln
Plant.
The
residence
time
of
these
sites
is
about
2
hours.

Sites
#
11
and
#
12
were
selected
to
represent
average
conditions
in
the
area
served
by
Lincoln
WTP.
Water
age
modeling
indicated
the
residence
times
for
these
sites
are
approximately
2
days.

Sites
#
13
and
#
14
represent
expected
high
HAA5
concentrations
in
the
zone
served
by
the
Lincoln
WTP.
These
sites
are
located
on
12­
inch
looped
lines
with
low
water
demand
near
the
extremities
of
the
system.
As
a
result,
travel
time
(
and
thus
water
age)
to
these
sites
is
approximately
3
to
4
days,
based
on
the
water
age
modeling.
However,
the
modeling
indicates
that
the
sites
are
always
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
10
fed
directly
from
the
Lincoln
WTP
and
routine
sampling
has
shown
that
the
total
chlorine
residual
at
these
sites
is
usually
about
2.3
mg/
L
during
the
summer.
As
a
result,
biodegradation
is
not
expected
to
occur,
and
high
HAA5
concentrations
are
expected.

Site
#
15
is
located
on
the
eastern
extremity
of
the
system
beyond
the
South
Tank.
Based
on
modeling,
it
was
determined
that,
due
to
the
travel
time
from
the
plant
to
this
site
and
the
effects
of
South
Tank,
the
water
age
at
this
site
typically
exceeds
5
days.
This
site
represents
high
TTHM.

Site
#
16
is
representative
of
high
TTHM
levels
in
the
mixing
zone
and
is
counted
as
one
of
the
eight
sites
required
for
the
Lincoln
WTP.
Modeling
shows
that
water
age
at
this
site
is
generally
high
(>
6
days)
throughout
the
day,
representing
water
that
has
traveled
a
significant
distance
and
that
has
usually
been
through
one
of
the
storage
tanks.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
11
Booster
chloramination
facility
Ground
storage
tank
Elevated
storage
tank
MIXING
ZONE
Adams
WTP
Lincoln
WTP
North
Tank
(
w/
pump
station)

South
Tank
West
Tank
Central
Tank
Booster
Station
B
Booster
Station
A
1
3
4
5
11
6
7
8
10
12
15
16
13
14
20
19
18
17
1
2
3
4
5
6
7
8
TCR
Site
used
for
SSS
TCR
Site
not
used
for
SSS
Stage
1
DBPR
Compliance
Site
##

##

#
2
9
7.
Map
of
the
distribution
system
showing
major
transmission
mains,
Stage
1
DBPR
compliance
sites,
and
SSS
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
12
8.
Summary
of
SSS
monitoring
results:

One
round
of
DBP
samples
was
collected
in
August
2005
at
the
SSS
sites
listed
in
section
6.
August
is
historically
the
high
DBP
month
for
Big
City.
The
results
from
this
sampling
are
presented
in
the
following
tables,
with
separate
sections
for
each
plant
and
the
sites
in
order
according
to
TTHM
results,
from
highest
to
lowest.
For
comparison,
Stage
1
DBPR
sampling
results
for
the
month
of
August
2005
and
the
LRAAs
as
of
August
2005
(
shown
in
parentheses)
are
also
presented
in
the
table
ranked
by
individual
TTHM
sample
results.

Adams
Plant
TTHM
and
HAA5
Test
Results
Site
#
Type
TTHM
Result
(
µ
g/
L)
HAA5
Result
(
µ
g/
L)

Adams
Plant
SSS
Sites
­
August
2005
SSS
#
7
High
TTHM
83
48
SSS
#
8
High
TTHM
62
45
SSS
#
3
High
HAA5
50
50
SSS
#
5
Average
Residence
Time
48
45
SSS
#
4
High
HAA5
48
32
SSS
#
6
Average
Residence
Time
45
30
SSS
#
2
Near
Entry
Point
34
28
SSS
#
1
Near
Entry
Point
32
30
Site
#
Type
TTHM
Result
(
LRAA)
(
µ
g/
L)
HAA5
Result
(
LRAA)
(
µ
g/
L)

Adams
Plant
Stage
1
DBPR
Sites
­
August
2005
Stage
1
#
4
Max.
Residence
Time
74
(
72)
28
(
25)

Stage
1
#
2
Avg.
Residence
Time
67
(
45)
56
(
50)

Stage
1
#
1
Avg.
Residence
Time
62
(
49)
45
(
36)

Stage
1
#
3
Avg.
Residence
Time
45
(
42)
68
(
62)
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
13
Lincoln
Plant
TTHM
and
HAA5
Test
Results
Site
#
Type
TTHM
Result
(
µ
g/
L)
HAA5
Result
(
µ
g/
L)

Lincoln
Plant
SSS
Sites
­
August
2005
SSS
#
16
High
TTHM
76
48
SSS
#
15
High
TTHM
73
36
SSS
#
13
High
HAA5
66
35
SSS
#
14
High
HAA5
62
58
SSS
#
11
Average
Residence
Time
52
40
SSS
#
12
Average
Residence
Time
50
42
SSS
#
9
Near
Entry
Point
40
34
SSS
#
10
Near
Entry
Point
44
32
Lincoln
Plant
Stage
1
DBPR
Sites
­
August
2005
Site
#
Type
TTHM
Result
(
LRAA)
(
µ
g/
L)
HAA5
Result
(
LRAA)
(
µ
g/
L)

Stage
1
#
7
Avg.
Residence
Time
59
(
43)
58
(
54)

Stage
1
#
8
Max.
Residence
Time
58
(
62)
30
(
27)

Stage
1
#
6
Avg.
Residence
Time
50
(
46)
41
(
33)

Stage
1
#
5
Avg.
Residence
Time
42
(
42)
41
(
38)

9.
Proposed
Stage
2B
monitoring
sites:

Big
City
is
a
system
serving
55,000
people
that
uses
two
surface
water
sources.
Therefore,
Big
City
is
required
to
designate
four
(
4)
Stage
2B
compliance
monitoring
sites
for
each
plant
resulting
in
a
total
of
eight
(
8)
Stage
2B
compliance
monitoring
sites.
A
summary
of
these
requirements
is
presented
in
the
following
table.

Stage
2B
Compliance
Monitoring
Requirements
Site
Criteria
Number
of
Sample
Sites
Adams
WTP
Influence
Zone
Lincoln
WTP
Influence
Zone
Stage
1
average
residence
time
sites
1
1
Representative
of
high
HAA5
1
1
Representative
of
high
TTHM
2
2
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
14
Based
on
the
modeling
results,
Stage
1
DBPR
data,
and
additional
DBP
sampling
results
at
the
SSS
monitoring
sites,
we
are
proposing
the
Stage
2B
compliance
monitoring
sites
listed
in
the
following
table.
The
rationale
for
their
selection
follows.

Stage
2B
Proposed
Compliance
Sample
Sites
Stage
2B
Sites
Site
Description
(
Previous
Site
ID)
No.
Plant
Type
1
Adams
Average
Stage
1
DBPR
average
residence
time
(
Stage
1
#
3)

2
Adams
Highest
HAA5
Stage
1
DBPR
average
residence
time
(
Stage
1
#
2)

3
Adams
Highest
TTHM
High
TTHM
from
Adams
Plant
(
SSS
#
7)

4
Adams
Highest
TTHM
Stage
1
DBPR
maximum
residence
time
(
Stage
1
#
4)

5
Lincoln
Average
Stage
1
DBPR
average
residence
time
(
Stage
1
#
7)

6
Lincoln
Highest
HAA5
High
HAA5
from
Lincoln
Plant
(
SSS
#
14)

7
Lincoln
Highest
TTHM
High
TTHM
from
Lincoln
Plant
(
SSS
#
16)

8
Lincoln
Highest
TTHM
High
TTHM
from
mixing
zone
(
SSS
#
15)

°
Stage
2B
Site
#
1:
This
is
the
average
residence
time
site
for
the
Adams
WTP
influence
area.
It
had
the
highest
HAA5
test
result
in
the
August
round
of
sampling
of
all
the
sites,
both
SSS
and
Stage
1
DBPR.
It
also
had
the
highest
HAA5
LRAA
(
62
µ
g/
L)
of
the
Stage
1
DBPR
sites,
and
this
LRAA
exceeds
the
MCL.
The
other
two
Stage
1
DBPR
average
residence
time
sites
had
higher
individual
TTHM
results
and
TTHM
LRAAs,
but
their
HAA5
results
and
LRAAs
were
significantly
less.
This
site
(
the
old
Stage
1
DBPR
#
3)
is
also
in
the
geographic
center
of
the
Adams
Plant
influence
area.

°
Stage
2B
Site
#
2:
This
is
the
representative
high
HAA5
site
for
the
Adams
WTP
influence
area.
It
had
the
second
highest
(
after
Stage
2B
#
1)
HAA5
result
of
the
12
sites.
It
is
located
on
the
south
central
region
of
the
distribution
system.

°
Stage
2B
Site
#
3:
This
is
one
of
two
representative
high
TTHM
sites
for
the
Adams
WTP
influence
area.
It
had
the
highest
TTHM
result
of
the
12
Adams
WTP
sites.
It
is
on
the
western
periphery
of
the
Adams
WTP
influence
area
and
downstream
of
Booster
Station
A,
which
is
used
intermittently
during
the
summer.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
15
°
Stage
2B
Site
#
4:
This
is
the
second
of
the
representative
high
TTHM
sites
for
the
Adams
WTP
influence
area.
It
had
the
second
highest
TTHM
result
of
the
12
Adams
sites,
and
because
it
was
the
Stage
1
DBPR
maximum
residence
time
location,
its
continued
use
will
maintain
an
uninterrupted
historic
record
of
DBP
levels
at
the
site.
It
is
in
the
mixing
zone
in
the
center
of
the
city.

°
Stage
2B
Site
#
5:
This
is
the
average
residence
time
site
for
the
Lincoln
WTP
influence
area.
It
had
the
highest
TTHM
and
HAA5
test
results
in
the
August
round
of
sampling
of
the
Stage
1
DBPR
average
sites.
Its
TTHM
LRAA
was
not
as
high
as
one
of
the
other
two
Stage
1
DBPR
average
sites
(
old
Stage
1
DBPR
#
6),
but
its
HAA5
LRAA
was
the
highest
HAA5
LRAA
of
the
Stage
1
sites
by
a
large
margin.
This
site
(
the
old
Stage
1
DBPR
#
7)
is
also
in
the
geographic
center
of
the
Lincoln
Plant
influence
area.

°
Stage
2B
Site
#
6:
This
is
the
representative
highest
HAA5
site
for
the
Lincoln
WTP
influence
area.
It
had
the
highest
HAA5
result
of
the
8
Lincoln
SSS
sites.
It
is
located
on
the
eastern
periphery
of
the
Lincoln
WTP
influence
area
and
has
historically
always
had
a
measurable
total
chlorine
residual,
which
is
most
likely
due
to
the
effect
of
the
frequent
operation
of
Booster
Station
B.

°
Stage
2B
Site
#
7:
This
is
the
first
of
two
representative
highest
TTHM
sites
for
the
Lincoln
WTP
influence
area.
It
had
the
highest
TTHM
result
of
the
12
Lincoln
WTP
sites,
and
is
located
in
the
mixing
zone
in
the
central
portion
of
the
city.

°
Stage
2B
Site
#
8:
This
is
the
second
of
the
representative
highest
TTHM
sites
for
the
Lincoln
WTP
influence
area.
It
had
the
second
highest
TTHM
result
of
the
12
Lincoln
sites.
It
is
on
the
eastern
edge
of
the
city.

The
map
on
the
following
page
shows
the
proposed
Stage
2B
compliance
monitoring
sites.

10.
Proposed
Stage
2B
Compliance
Monitoring
Schedule:

Stage
2B
compliance
monitoring
will
be
scheduled
for
the
first
week
of
February,
May,
August,
and
November.
This
is
the
same
as
the
Stage
1
DBPR
and
Stage
2A
DBPR
sampling,
because
August
is
the
historic
month
of
maximum
DBP
levels
and
water
temperature
in
the
distribution
system.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
16
Booster
chlorination
facility
Ground
storage
tank
Elevated
storage
tank
MIXING
ZONE
Adams
WTP
Lincoln
WTP
North
Tank
(
w/
pump
station)

South
Tank
West
Tank
Central
Tank
Booster
Station
B
Booster
Station
A
3
8
7
1
5
Stage
2B
Representative
High
TTHM
Stage
2B
Representative
High
HAA5
Stage
2B
Average
Residence
Time
#

#

#
6
2
4
11.
Proposed
Stage
2B
compliance
monitoring
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
K­
17
This
page
intentionally
left
blank.
Appendix
L
IDSE
System­
Specific
Study
Using
Historical
Data
This
appendix
is
provided
as
an
example
IDSE
report
for
a
producing
system
opting
to
complete
a
System­
Specific
Study
(
SSS)
using
historical
DBP
data.

Chapter
3
presents
detailed
guidance
on
the
requirements
for
performing
an
SSS
with
historical
data
and
guidance
on
the
selection
of
Stage
2B
compliance
monitoring
sites
using
SSS
data.
Chapter
3
also
presents
the
IDSE
reporting
requirements
for
systems
conducting
an
SSS.
The
application
of
the
basic
guidance
on
the
use
of
historical
data
to
select
sites
meeting
the
SMP
site
criteria
and
the
use
of
the
data
to
select
Stage
2B
compliance
monitoring
sites
is
shown
in
this
example,
along
with
several
instances
of
the
use
of
best
professional
judgement
being
applied.

The
italicized
text
within
the
appendix
consists
of
comments
and
explanations
and
is
not
intended
to
represent
the
recommended
content
of
an
actual
IDSE
Report.
This
page
intentionally
left
blank.
Initial
Distribution
System
Evaluation
Report
for
Magnolia
City
PWSID
Number:
US0000000
Address:
P.
O.
Box
1234
Magnolia
City,
US
11111­
1234
Contact
Person:
Ms.
Mary
Flower,
P.
E.

Phone
Number:
234­
555­
1111
Fax
Number:
234­
555­
2222
Email
Address:
Mflower@
ci.
magnolia.
us
System
Type:
Community,
surface
water
Population
Served:
125,000
This
page
intentionally
left
blank.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
1
1.
System
Description:

This
section
of
the
report
should
include
a
summary
of
typical
system
operating
characteristics
(
and
how
they
change
on
a
seasonal
basis
if
appropriate)
explaining
how
sources
are
used
to
meet
system
demands,
where
high
water
age
is
expected
to
occur,
and
any
special
aspects
of
operation
that
could
affect
DBP
concentrations
in
the
distribution
system.
Information
about
water
treatment
processes
and
source
water
quality
data
is
also
part
of
this
section,
including
a
description
of
actual
residence
times
within
the
water
treatment
plant
and
the
distribution
system.

General
system
characteristics:
Service
Area:
Magnolia
City
plus
surrounding
suburban
areas
Production:
Annual
average
daily
demand
35
MGD
Source
Water
Information:
Grand
Falls
River
pH:
from
6.7
to
7.7
Alkalinity:
from
73
to
104
mg/
L
as
CaCO3
TOC:
from
1.8
to
5.4
mg/
L
as
C
Entry
points
(
tied
to
source(
s)
and
identification
of
service
area(
s)
under
the
influence
of
each
entry
point:
Entry
points:
River
Run
Plant,
serves
the
entire
service
area
Treatment
Provided:
River
Run
Plant,
coagulation
(
with
ferric
chloride),
flocculation,
sedimentation,
and
dual
media
filtration
(
filter
loading
rates
are
approximately
4
gpm/
sf).
Chlorine
is
used
for
both
primary
and
residual
disinfection.

Description
of
distribution
system:
Distribution
system
(
estimated
length
of
lines
and
range
of
diameter):
About
800
miles,
4"
­
56"

11storage
tanks
with
a
total
of
19
MG
capacity
4
elevated
tanks
2.0
MG
each
(
8
MG)
2
elevated
tanks,
1.5
MG
(
3
MG)
2
elevated
tanks,
0.5
MG
(
1
MG)
3
ground
tanks
(
two
2
MG
and
one
3
MG,
7
MG
total
capacity)

The
average
residence
time
of
water
in
the
distribution
system
is
estimated
as
two
days.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
2
Pump
stations:
Station
#
1
is
located
at
the
ground
storage
tank
on
North
Boulevard.
This
station
is
primarily
used
during
peak
demands
and
low
pressure
situations.
The
pump
is
timed
to
turn
on
in
the
morning
and
evening
during
peak
demand,
and
when
the
pressure
drops
below
40
psi
at
a
point
downstream
of
the
pump
station.

Stations
#
2
and
#
3.
These
pumps
are
used
to
boost
system
pressure
when
the
pressure
in
the
areas
downstream
of
these
pumps
(
Flower
Village
and
Friendship
Heights)
drops
below
40
psi.

Booster
chlorination
facilities:
Facility
#
1
is
located
in
proximity
to
Freedom
Square
(
downstream
of
the
Columbus
St.
storage
tank).
This
facility
is
occasionally
used
during
the
summer
when
remote
locations
downstream
of
the
booster
chlorination
facility
lose
residual.

Facility
#
2
is
located
at
the
Flower
Village
elevated
tank,
in
an
area
of
the
distribution
system
where
chlorine
residuals
are
frequently
low.

Facility
#
3
is
located
near
the
North
Village
(
downstream
of
the
north
storage
tank)
in
an
area
of
the
distribution
system
where
chlorine
residuals
are
frequently
low.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
3
River
Run
WTP
P
Elevated
Storage
Tank
Pump
station
Booster
chlorination
station
P
Ground
Storage
Tank
P#
1
Flower
Village
Friendship
Heights
P#
3
P#
2
1
2
3
North
EST
Flower
Village
EST
Brown
Pike
EST
Columbus
Street
EST
2.
Schematic
of
the
distribution
system:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
4
3.
SMP
monitoring
requirements:

Magnolia
City
is
a
system
serving
125,000
people
that
uses
one
surface
water
source.
Instead
of
an
IDSE
SMP,
an
IDSE
SSS
has
been
performed
based
on
historical
system­
specific
monitoring
data
that
are
comparable
or
superior
to
data
that
would
be
collected
at
monitoring
sites
required
by
the
Standard
Monitoring
Program.
A
comparison
of
SMP
monitoring
site
requirements
and
sites
used
as
a
part
of
this
SSS
is
presented
in
the
following
table.

Comparison
of
SMP
and
SSS
Monitoring
Sites
Site
Criteria
Number
of
Sample
Sites
Required
by
SMP
Provided
in
SSS
Near­
entry
to
the
distribution
system
1
1
Average
residence
time
2
4
Representative
of
high
TTHM
3
5
Representative
of
high
HAA5
2
2
Total
8
12
4.
Description
of
Historical
Data:

The
selected
SSS
sites
have
been
monitored
three
times
a
year
for
a
period
of
five
years
(
1999­
2003).
This
monitoring
was
conducted
separately
from
Stage
1
DBPR
compliance
monitoring.
TTHM
testing
for
the
entire
5­
year
period
was
performed
by
certified
labs.
HAA5
testing
was
performed
by
certified
labs
beginning
in
2002,
so
HAA5
data
provided
by
non­
certified
labs
in
the
previous
years
were
not
considered
and
have
not
been
included
in
this
report.

During
the
5­
year
period
of
DBP
monitoring,
there
were
no
significant,
long­
term
changes
made
at
the
water
treatment
plant
or
in
the
operation
of
the
distribution
system.
There
have
been
no
process
changes
at
the
plant,
and
no
new
tanks,
pump
stations,
or
significant
water
mains
added
to
the
distribution
system.
A
small
booster
chlorination
facility
was
added
to
the
North
EST
in
the
spring
of
2003,
which
allows
chlorine
to
be
added
to
water
flowing
out
of
the
tank.
This
helped
increase
the
chlorine
residual
levels
in
the
area
around
and
past
the
tank
in
the
summer
of
2003.
The
area
affected
by
this
new
chlorine
booster
facility
is
limited
to
the
area
that
receives
water
from
this
0.5
MG
tank,
so
the
area
is
relatively
small.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
5
Available
Data:

Report
all
data
that
helped
in
site
selection.
If
you
have
bromide,
TOC,
or
HPC
data,
these
may
be
helpful
for
justifying
selection
of
Stage
2B
sites.

Table
L.
1
summarizes
free
chlorine
residual
data
at
each
of
the
city's
24
TCR
monitoring
sites.
Of
these
24
sites,
12
have
been
monitored
for
DBP's
over
the
last
5
years
and
were
selected
as
SSS
monitoring
sites.
Table
L.
2
presents
HPC
data
for
the
24
TCR
monitoring
sites
The
historical
sampling
stations
were
chosen
in
1999
to
represent
diverse
geographical
areas
of
the
distribution
system,
using
water
quality
data
collected
in
1997
and
1998
for
free
residual
chlorine
(
Table
L.
1)
and
heterotrophic
plate
counts
(
HPC)
(
Table
L.
2).
The
extent
of
this
network
of
12
monitoring
stations
is,
in
our
opinion,
superior
to
the
eight
monitoring
stations
required
by
the
IDSE
SMP
for
a
system
under
the
influence
of
one
surface
water
source.

Table
L.
3
in
section
7
presents
TTHM
and
HAA5
test
results
for
the
12
TCR
monitoring
sites
where
TTHM
and
HAA5
testing
has
been
conducted
on
a
regularly
scheduled
basis
for
the
last
5
years.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
6
Table
L.
1
Magnolia
City
 
Free
Chlorine
Residual
Data
(
mg/
L)

TCR
Site
#
Location
SSS
#
11/
97
02/
98
05/
98
08/
98
Average
1
Lakeshore
Dr
7
0.5
0.8
0.9
0.4
0.7
2
Dogwood
Dr
5
0.7
0.6
0.8
1.0
0.8
3
Brown
Pike
6
0.6
0.9
1.1
0.8
0.9
4
Near
Heights
8
0.7
0.7
0.4
0.2
0.5
5
Museum
Rd
2
0.6
0.7
0.6
0.8
0.7
6
Country
Club
Rd
9
0.2
0.6
0.3
0.2
0.3
7
Logan
Pl
12
0.5
0.3
0.2
0.5
0.4
8
Langley
Ave
0.8
0.9
1.2
1.1
1.0
9
Grant
Hill
Pl
0.6
0.6
0.5
0.9
0.7
10
River
Run
entry
point
1
1.4
1.2
1.3
1.7
1.3
11
Gray
Sq
10
0.3
0.6
0.1
0.0
0.1
12
Pink
Ln
0.2
0.3
0.5
0.3
0.6
13
Oak
Dr
0.8
0.9
0.3
0.8
0.7
14
Sea
Dr
0.2
0.8
0.8
0.5
0.6
15
River
Rd
0.2
1.0
0.7
0.1
0.6
16
Lake
Ave
0.9
0.7
1.0
1.2
1.0
17
Hardwood
Sq
0.9
1.2
1.0
0.8
1.0
18
Long
Dr
1.6
1.4
1.6
1.5
1.5
19
Colonial
Plaza
0.8
0.6
0.9
0.8
0.8
20
Butler
Pl
4
0.6
0.2
0.5
0.4
0.4
21
Sunset
Rd
11
ND
0.1
0.1
0.3
0.1
22
Gatewood
Ln
0.2
0.2
0.2
0.5
0.3
23
Morgan
Ave
3
0.6
0.4
0.4
0.6
0.5
24
Central
Street
ND
0.2
ND
0.1
0.1
ND
­
Non
Detect
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
7
Table
L.
2
Magnolia
City
 
Heterotrophic
Plate
Counts
(
cfu/
mL)

TCR
Site
#
Location
SSS
#
11/
97
02/
98
05/
98
08/
98
Average
1
Lakeshore
Dr
7
50
34
63
113
65
2
Dogwood
Dr
5
53
64
123
94
83
3
Brown
Pike
6
56
42
276
345
180
4
Near
Heights
8
82
136
246
146
152
5
Museum
Rd
2
66
53
53
153
81
6
Country
Club
Rd
9
70
212
332
356
242
7
Logan
Pl
12
54
65
65
93
69
8
Langley
Ave
69
43
43
37
48
9
Grant
Hill
Pl
43
34
224
156
114
10
River
Run
entry
point
1
67
14
42
35
40
11
Gray
Sq
10
140
215
615
857
456
12
Pink
Ln
280
163
263
746
363
13
Oak
Dr
50
42
522
223
209
14
Sea
Dr
140
66
236
364
201
15
River
Rd
196
45
425
853
380
16
Lake
Ave
53
42
72
84
63
17
Hardwood
Sq
35
43
45
64
47
18
Long
Dr
12
8
12
34
17
19
Colonial
Plaza
78
86
364
384
228
20
Butler
Pl
4
34
76
89
97
74
21
Sunset
Rd
11
156
278
359
469
315
22
Gatewood
Ln
233
214
546
656
412
23
Morgan
Ave
3
35
62
92
147
84
24
Central
Street
68
175
375
399
254
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
8
5.
Description
historical
sample
sites:

A
description
of
the
characteristics
used
to
select
the
twelve
historical
sites
used
for
DBP
monitoring
in
the
distribution
system
is
given
here.
These
sites
are
presented
graphically
in
section
3.
Historical
DBP
data
for
these
sites
is
presented
in
section
8.

Historical
Site
#
1
 
Entry
point
to
the
distribution
system
for
River
Run
Water
Treatment
Plant.
This
site
is
located
just
after
the
first
significant
group
of
connections
downstream
of
the
plant.

Historical
Site
#
2
 
Represents
average
residence
time
of
water
leaving
the
plant.
We
estimated
the
point
where
the
chlorine
decays
to
about
50
percent
of
its
original
residual
concentration
(
at
the
high
service
pumps).
There
are
no
storage
facilities
between
the
plant
and
this
site.

Historical
Site
#
3
 
Represents
average
residence
time.
Water
at
this
site
does
not
go
through
a
storage
facility,
and
the
chlorine
residual
is
generally
35
to
40
percent
of
the
River
Run
Plant
effluent
concentration.
We
attribute
this
additional
loss
of
chlorine
to
the
fact
that
the
transmission
and
distribution
lines
serving
this
area
are
older
unlined
cast
iron
and
have
significant
build­
up
of
corrosion
by­
products
(
tubercles).
We
believe
that
these
corrosion
by­
products
exert
a
chlorine
demand
which
results
in
lower
chlorine
residual
at
this
site,
although
it
is
probably
lower
in
water
age
than
Site
#
2.

Historical
Site
#
4
 
Represents
average
residence
time.
The
site
is
used
as
an
alternative
site
for
our
coliform
and
chlorine
residual
monitoring.

Historical
Site
#
5
 
Represents
average
residence
time.
The
chlorine
residual
at
this
site
is
generally
45
to
50
percent
of
the
plant
effluent
concentration.

Historical
Site
#
6
 
Represents
high
TTHM
levels.
This
sampling
site
is
downstream
of
the
Brown
Pike
Storage
Tank
(
a
1.5
MG
elevated
tank).
The
sampling
station
is
located
downstream
of
the
tank
before
the
last
group
of
connections
(
approximately
0.5
miles)
to
be
representative
of
water
delivered
to
customers.

Historical
Site
#
7
 
Represents
high
TTHM
levels.
This
site
is
the
last
dedicated
sampling
site
downstream
of
the
Flower
Village
EST
and
is
used
for
routine
Total
Coliform
Rule
and
chlorine
residual
monitoring.
We
have
over
7
years
of
data
from
this
site.
This
site
is
located
before
the
last
group
of
connections
near
the
end
of
the
system,
where
the
water
demand
tends
to
be
relatively
low.

Historical
Site
#
8
 
Represents
high
TTHM
levels.
This
sample
site
is
a
faucet
at
a
connection
located
in
a
zone
of
the
distribution
system
that
has
been
recently
developed.
Chlorine
residuals
are
normally
in
the
0.2
to
0.7
mg/
L
range.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
9
Historical
Site
#
9
 
Represents
high
TTHM
levels.
This
site
is
downstream
of
the
North
Storage
Tank,
a
0.5
MG
elevated
tank
with
a
booster
chlorination
facility
that
was
recently
added
to
aid
in
maintaining
a
chlorine
residual.

Historical
Site
#
10
 
Represents
high
TTHM
levels.
This
site
has
been
problematic
in
the
past,
with
the
occurrence
of
coliform
bacteria,
non­
detectable
chlorine
residuals,
high
heterotrophic
plate
count,
and
odor
complaints.
A
4­
inch
blow­
off
was
installed
downstream
of
this
site,
but
the
site
continues
to
have
poor
water
quality.

Historical
Site
#
11
 
Represents
high
HAA5
levels.
Although
chlorine
residual
levels
are
often
low
at
this
site,
there
has
never
been
an
occurrence
of
a
heterotrophic
plate
count
greater
than
500
cfu/
mL
or
a
positive
coliform
bacteria
test.

Historical
Site
#
12
 
Represents
high
HAA5
levels.
Sample
tap
is
a
hose
bib
at
a
building
located
in
a
zone
of
the
distribution
system
with
water
age
greater
than
average.
Chlorine
residual
at
this
site
ranges
from
0.2
to
0.5
mg/
L,
and
the
heterotrophic
plate
count
is
consistently
below
100
per
mL
all
year
round.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
10
River
Run
WTP
P
Elevated
Storage
Tank
Pump
station
Booster
chlorination
station
P
Ground
Storage
Tank
P#
1
3
Historical
DBP
monitoring
site
Stage
1
DBPR
site
Flower
Village
Friendship
Heights
P#
3
P#
2
1
2
3
North
EST
Flower
Village
EST
Brown
Pike
EST
Columbus
Street
EST
8
6
2
7
4
5
1
12
9
11
10
1
2
3
4
6.
Map
of
the
distribution
system
showing
major
transmission
mains,
numbered
Stage
1
DBPR
compliance
sites,
and
numbered
historical
sample
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
11
7.
Summary
of
historical
DBP
data
and
Stage
1
DBPR
compliance
data:

Data
for
five
years
of
TTHM
monitoring
and
two
years
of
HAA5
monitoring
are
presented
in
Table
L.
3.
Data
were
collected
three
times
a
year,
during
April,
July,
and
October.
No
winter
samples
were
taken.
The
historical
monitoring
did
not
include
sampling
during
August
 
the
peak
historical
month
for
water
temperature
and
DBPs
(
based
on
Stage
1
DBPR
compliance
monitoring
provided
below).
Therefore,
a
single
set
of
additional
samples
was
collected
at
the
12
historical
sites
in
August
2003
and
the
results
included
as
part
of
the
2003
monitoring
data
in
the
following
table.
The
August
value
is
included
in
the
table
to
allow
for
a
comparison
between
the
individual
sampling
results.
However,
the
August
2003
results
were
not
included
in
the
calculation
of
the
2003
yearly
averages
because
this
would
have
prevented
a
direct
comparison
of
the
2003
averages
to
the
averages
from
previous
years
that
do
not
include
an
August
sample
result.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
12
Table
L.
3
Magnolia
City
Historical
DBP
Monitoring
Results
(
1999­
2003)

SSS
Sample
Site
Year
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Monitoring
Data1
08/
03
Avg
Monitoring
Data1
08/
03
Avg
#
1
­
Plant
entry
point
1999
36,
92,
89
72
2000
24,
78,
93
65
2001
33,
15,
24
24
2002
24,
35,
46
35
21,
15,
68
35
2003
37,
45,
58
69
47
38,
58,
53
46
50
#
2
­
Average
residence
time
1999
66,
82,
80
76
2000
76,
94,
83
84
2001
72,
98,
79
83
2002
51,
75,
80
69
29,
35,
41
35
2003
44,
68,
71
78
61
45,
50,
48
56
48
#
3
­
Average
residence
time
1999
56,
71,
63
63
2000
36,
84,
103
74
2001
62,
68,
54
61
2002
41,
58
,
69
70
24,
23,
74
40
2003
41,
65,
70
74
59
47,
63,
59
48,
56
#
4
­
Average
residence
time
1999
61,
77,
75
71
2000
68,
86,
75
79
2001
67,
88,
79
78
2002
56,
75,
75
69
34,
33,
54
40
2003
47,
71,
74
85
66
43,
68,
63
59
58
#
5
­
Average
residence
time
1999
55,
70,
62
62
2000
35,
83,
82
67
2001
60,
66,
52
59
2002
43,
60
,
71
72
22,
21,
64
37
2003
39,
63,
69
92
57
48,
62,
58
36
56
#
6
­
High
TTHM
1999
85,
71,
93
83
2000
82,
92,
102
92
2001
70,
72,
95
79
2002
61,
81,
85
76
40,
56,
68
55
2003
68,
76,
80
123
75
50,
50,
58
23
53
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
SSS
Sample
Site
Year
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Monitoring
Data1
08/
03
Avg
Monitoring
Data1
08/
03
Avg
July
2003
­
Proposal
Draft
L­
13
#
7
­
High
TTHM
1999
82,
69,
83
78
2000
92,
102,
112
102
2001
90,
92,
105
96
2002
71,
91,
95
86
45,
33,
25
34
2003
88,
96,
100
98
95
30,
60,
68
63
53
#
8
­
High
TTHM
1999
75,
80,
82
79
2000
65,
103,
112
93
2001
60,
106,
152
106
2002
53,
80,
91
75
32,
31,
23
29
2003
89,
55,
99
152
81
28,
33,
49
44
37
#
9
­
High
TTHM
1999
80,
85,
87
84
2000
75,
93,
109
92
2001
70,
110,
98
93
2002
73,
100
,
101
95
35,
36,
28
34
2003
84,
90,
94
132
89
31,
39,
59
47
45
#
10
­
High
TTHM
1999
78,
87,
89
85
2000
85,
103,
119
102
2001
60,
120,
108
96
2002
75,
102
,
103
98
34,
36,
30
33
2003
54,
70,114
92
79
45,
19,
29
26
31
#
11
­
High
HAA5
1999
56,
71,
63
63
2000
37,
85,
84
69
2001
63,
69,
55
62
2002
42,
58
,
69
69
42,
71,
55
56
2003
41,
65,
71
83
59
50,
65,
79
82
65
#
12
­
High
HAA5
1999
56,
72,
70
66
2000
63,
81,
70
74
2001
62,
83,
74
73
2002
51,
70,
70
64
44,
43,
25
37
2003
42,
66,
69
90
61
53,
68,
83
78
68
1
Data
obtained
from
sampling
at
approximate
90
day
intervals
each
year
are
listed
in
order
for
April,
July,
and
October.
Bold
values
are
August
2003
results
and
are
not
included
in
the
calculated
averages.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
14
Stage
1
DBPR
sampling
occurred
as
scheduled
from
November
2002
through
August
2003.
These
data
are
presented
in
the
following
table.

Magnolia
City
 
Stage
1
DBPR
Monitoring
Results
for
2003
Monitoring
Site
TTHM
(
µ
g/
L)
HAA5
(
µ
g/
L)

Individual
Results1
LRAA
Individual
Results1
LRAA
Average
residence
time
#
1
45,
34,
51,
67
49
24,
27,
43,
50
36
Average
residence
time
#
2
36,
42,
41,
49
42
42,
47,
50,
61
50
Average
residence
time
#
3
32,
34,
43,
72
45
50,
62,
62,
73
62
Maximum
residence
time
#
4
64,
68,
74,
83
72
21,
25,
26,
28
25
1
Data
listed
in
order
for
November,
February,
May,
and
August
quarterly
sampling.

8.
Proposed
Stage
2B
monitoring
sites:

Magnolia
City
is
a
system
serving
125,000
people
and
uses
one
surface
water
source.
Therefore,
Big
City
is
required
to
propose
a
total
of
four
Stage
2B
compliance
monitoring
sites.
A
summary
of
these
requirements
is
presented
in
the
following
table.

Stage
2B
Compliance
Monitoring
Requirements
Site
Criteria
Number
of
Sites
Stage
1
average
residence
time
sites
1
Representative
of
high
HAA5
1
Representative
of
high
TTHM
2
Based
on
historical
DBP
data,
Stage
1
compliance
data,
and
other
available
water
quality
data
(
free
chlorine
residual
and
HPC),
we
are
proposing
the
Stage
2B
monitoring
sites
listed
in
the
following
table.
The
rationale
for
their
selection
follows.
A
schematic
of
the
sites
is
presented
in
section
9.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
15
Proposed
Stage
2B
Compliance
Monitoring
Sites
Sample
Site
Site
Description
Stage
2B
Site
#
1
Stage
1
DBPR
#
3
Stage
2B
Site
#
2
SSS
#
11
­
High
HAA5
Stage
2B
Site
#
3
SSS
#
7
­
High
TTHMs
Stage
2B
Site
#
4
SSS
#
9
­
High
TTHMs
1.
One
Stage
2B
monitoring
site
representative
of
average
residence
time
must
be
selected
from
the
three
Stage
1
DBPR
average
residence
time
sites.
Stage
1
DBPR
#
3
was
retained
as
the
Stage
2B
monitoring
site
representative
of
average
residence
time.
This
site
had
the
highest
individual
TTHM
concentration
and
the
highest
HAA5
LRAA.
Because
Stage
1
#
3'
s
HAA5
LRAA
was
much
greater
than
the
HAA5
LRAAs
of
the
other
two
Stage
1
sites
and
the
TTHM
LRAAs
of
all
three
sites
were
relatively
close,
the
decision
was
made
to
retain
Stage
1
#
3
as
the
Stage
2B
average
residence
time
compliance
site.

2.
One
Stage
2B
monitoring
site
must
be
representative
of
the
highest
HAA5
levels
in
the
distribution
system.
Among
all
the
SSS
and
Stage
1
DBPR
sites,
SSS
#
12
had
the
highest
average
HAA5
value
during
the
2003
sampling
period
(
68
µ
g/
L)
but
had
a
much
lower
average
(
37
µ
g/
L)
in
2002.
SSS
#
11
had
the
highest
average
HAA5
values
when
considered
together
for
2002
and
2003,
the
only
site
to
have
such
consistently
high
values.
It
is
believed
that
the
startup
of
Booster
Chlorination
Facility
#
2
in
June
2003
resulted
in
an
increase
in
HAA5
values
at
SSS
#
12,
compared
to
the
values
seen
the
previous
summer.
Operation
of
Booster
Chlorination
Facility
#
2
is
on
an
as
needed
basis,
so
it
appears
that
if
the
booster
facility
is
not
operating,
the
HAA5
levels
at
SSS
#
12
will
be
much
lower.
Also,
SSS
#
12
is
geographically
and
hydraulically
a
little
too
close
to
Stage
2B
#
3.
Therefore,
based
on
our
professional
judgement
of
these
factors,
SSS
#
11
is
proposed
as
the
Stage
2B
compliance
monitoring
site
representative
of
highest
HAA5.

3.
Two
Stage
2
DBPR
monitoring
sites
must
be
representative
of
highest
TTHM
levels.
Among
all
the
SSS
and
Stage
1
DBPR
sites,
SSS
#
7
and
#
9
consistently
had
the
highest
average
TTHM
values
during
1999­
2003.
Therefore,
we
propose
SSS
sites
#
7
and
#
9
as
the
Stage
2B
compliance
monitoring
sites
representative
of
highest
TTHM.
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
16
River
Run
WTP
P
Elevated
Storage
Tank
Pump
station
Booster
chlorination
station
P
Ground
Storage
Tank
P#
1
Stage
2B
representative
high
HAA5
location
Stage
2B
representative
high
TTHM
location
#
#

#
Stage
2B
average
residence
time
location
Flower
Village
Friendship
Heights
P#
3
P#
2
1
2
3
North
EST
Flower
Village
EST
Brown
Pike
EST
Columbus
Street
EST
1
3
4
2
9.
Proposed
Stage
2B
compliance
sample
sites:
Stage
2
DBPR
Initial
Distribution
System
Evaluation
Guidance
Manual
July
2003
­
Proposal
Draft
L­
17
This
page
intentionally
left
blank.