1. Graywater
and
Groundwater:
Site
Tes2ng
Considera2ons
Todd
Jarvis,
Ph.D.
Cer2fied
Engineering
Geologist
Cer2fied
Water
Rights
Examiner
2. What
others
are
saying..
Graywater
puts
an
immense
strain
on
leach
fields
,
and
helps
to
max
out
your
sep7c
tank.
Diver&ng
your
graywater
into
your
landscape
helps
alleviate
this
problem
and
actually
leads
to
less
contamina&on
of
groundwater.
In
fact,
the
ecosystem
of
a
mulch
basin
around
a
plant
makes
for
a
very
effec7ve
wastewater
treatment
system…and
wastewater
is
filtered
more
effec&vely
when
released
on
the
surface
of
the
ground
rather
than
under.
The
microbes
in
the
soil
convert
organic
impuri7es
in
the
wastewater
into
nutrients,
which
are
then
available
for
uptake
by
the
roots
of
the
plants.
The
result
is
water
that
is
purer
than
what
is
discharged
from
a
sewage
treatment
plant.
“Graywater
irriga2on
systems
save
water
and
money”
-‐
Dave
Walzer
Santa
Cruz
Sen&nel
interviewing
Laura
Allen
of
Graywater
Ac&on-‐
02/27/2010
3. What
others
are
saying..
Contamina2on
of
surface
water.
If
grey
water
does
not
percolate
through
the
soil,
it
can
flow
into
creeks
or
other
waterways
untreated.
Solu7on:
discharge
grey
water
underground
or
into
a
mulch-‐filled
basin.
Don't
apply
grey
water
to
saturated
soils.
Apply
grey
water
intermiHently
so
that
it
soaks
in
and
soil
can
aerate
between
waterings.
In
general,
contained
grey
water
applica&on
at
least
50
feet
from
a
creek
or
lake
is
not
a
problem.
Contamina2on
of
groundwater.
It
is
all
but
impossible
to
contaminate
groundwater
with
a
grey
water
system.
However,
property
owners
with
wells
should
not
irrigate
with
grey
water
any
closer
to
the
well
than
county
regula7ons
allow
for
a
sep7c
tank
leachfield.
Oasis
Design
aka
Art
Ludwig
4. Why
do
we
need
to
heed
what
others
are
saying?
MIT
Urban
Planning
Professor
and
conflict
resolu7on
expert
Lawrence
Susskind
indicates
that
newspaper
ar7cles
and
leHers
to
the
editor
are
important
in
the
discourse
on
resource
planning
because
the
United
States
is
a
representa7ve
democracy
where
“...we
can
count
on
the
media
to
help
ci&zens
educate
themselves
about
the
issues
being
deliberated
by
their
elected
representa&ves".
Journal
of
Water
Resources
Planning
and
Management
editorial
by
former
long7me
World
Bank
consultant
and
Harvard
Professor
John
Briscoe
7tled
"The
prac)ce
and
teaching
of
American
water
management
in
a
changing
world",
Briscoe
indicates
that:
"The
new
genera&on
of
partnerships
must
involve,
inter
alia:
“A
focus
on
the
real
world,
and
thus
an
emphasis
on
partnerships
(a)
between
prac&&oners-‐who-‐think,
and
researchers-‐who-‐understand-‐prac&ce...and
(b)
to
engage
with
the
progressive
private
sector
which
is
likely
to
be
the
source
of
much
innova&on
in
the
water
domain.”
5. State
DHS
Guidelines
Graywater
is
not
listed
as
a
“Poten2al
Contaminant
Source”
According
to
Tom
PaUee
of
Groundwater
Sec2on
of
DHS,
unofficial
concern
about
graywater
rests
with
poten2al
viral
contaminants
within
the
“ Two-‐year
Time
of
Travel
Zones”
in
Public
Water
Supply
Wells.
6. State
DHS
Guidelines
Summary
of
Oregon's
Suscep2bility
(Sensi2vity)
Analysis
Procedures
Matrix
Evalua2on
A
series
of
matrices
is
used
to
evaluate
the
poten2al
of
[1]
water
migra2ng
from
the
surface
to
the
aquifer
and
[2]
a
given
contaminant
persis2ng
and
moving
with
the
water.
In
each
matrix,
two
parameters
are
ploUed.
Their
intersec2on
within
the
matrix
yields
a
score
from
1
to
10.
The
higher
the
score,
the
greater
the
poten2al
that
these
parameters
will
contribute
to
aquifer
suscep2bility.
1.
Traverse
Poten2al.
2.
Infiltra2on
Poten2al.
3.
Mobility
Poten2al.
4.
Leach
Poten2al.
5.
Suscep2bility.
7. State
UIC
Guidelines
340-‐044-‐0018
Authoriza2on
of
Underground
Injec2on
by
Rule
Basic
requirements
for
all
storm
water
injec&on
systems
authorized
by
rule
–
(E)
The
injec&on
system
is
not
located
within
the
2
year
2me-‐of-‐travel
zone
as
delineated
by
the
Oregon
Health
Division
or
closer
than
500
feet
to
a
public
water
supply
well,
whichever
is
more
protec2ve.
(G)
The
injec&on
system
does
not
exceed
a
depth
of
100
feet
and
does
not
discharge
directly
into
groundwater
or
below
the
highest
seasonal
groundwater
level.
(H)
A
confinement
barrier
or
a
natural
or
engineered
filtra&on
medium
is
present
between
the
base
of
the
injec2on
system
and
the
highest
seasonal
groundwater
level
and
prevents
contaminants
from
reaching
groundwater,
or
the
owner
or
operator
implements
best
management
prac2ces
that
prevent
or
treat
storm
water
contamina2on
before
injec2on.
8. State
On-‐Site
Guidelines
• 340-‐071-‐0150
Site
Evalua2on
Procedures
for
On
Site
Sep2c
Systems.
For
the
Site
Evalua7on
Report,
the
standards
include,
among
other
things
"...applicants
must
provide
at
least
two
test
pits,
with
dimensions
and
configura7on
as
directed
by
the
agent,
located
approximately
75
feet
apart
and
within
the
area
of
the
proposed
system,
including
the
repair/
replacement
area",
where
"Soil
profiles
determined
from
test
pits
provided
by
applicant"
and
"Water
table
levels
(as
indicated
by
condi&ons
associated
with
satura&on
or
water
table
observa&ons)".
Site
tes&ng
using
On-‐site
or
UIC
methods
require
holes
which
can
serve
as
conduits
for
greywater
to
reach
groundwater
without
treatment
9. Unintended
Consequences
of
using
On-‐site
or
UIC
si2ng
standards
-‐
“Guerilla
Well-‐fare”
or
Dueling
Expert
Situa2ons
From Jarvis (2010) Water Wars, War of the
Well, and Guerilla Well-fare, Journal of
Ground Water
10. Site
Evalua2on
and
Permijng
Situa2on
“Invasive
versus
Self
Evalua2on”
Oregon On-site or UIC standards applied to a graywater?
"Ludwig's Law"- "Experience with groundwater contamination from
septics [and UIC] does not translate to greywater".
“OOSU corollary to Ludwig's Law” - "Experience with groundwater
contamination from greywater does translate to septics".
11. Recommenda2on?
The
Shovel
Test
and
Common
Sense
Paul Stanton, Duckboy® Cards Inc.
12. The
Conflict
over
Graywater
“Green
versus
Black
&
White”
"Graywater reuse is viewed by the green-leaning
layperson as the panacea for water shortages,
groundwater depletion, surface water contamination,
and climate change"; and
"Graywater is seen by society's public health
guardians (including the water utilities) as a threat to
health and safety of the users themselves and their
neighbors”.
"Neither of these caricatures of graywater is accurate,
although an element of truth resides in each".
AWWA – White Paper on Graywater (2010)
13. Mul2ple
Ways
of
Knowing
Portland State University Professor of Urban Studies
and Planning Connie Ozawa suggests that any system
developed for folding science and other sorts of
information into decisionmaking must be able to make
space for silent voices and multiple ways of knowing.
Thank
you
for
your
aUen2on.
