HomeMy WebLinkAbout120717_OC_pest_approach_citySAN DIEGO CREEK, UPPER AND LOWER NEWPORT BAY ORGANOCHLORINE TMDL
Shelly Anghera, Ph.D.
December 7, 2017
1
TMDL FACTS
Includes multiple limits for organochlorine pesticides in
Upper and Lower Newport Bay
DDTs, PCBs, toxaphene, chlordane
Water, sediment, fish tissue
Requires monitoring and special studies
Final compliance is due December 31, 2020
County is lead agency and the City has been
contributing financially
2
NEWPORT BAY CURRENT CONDITION
Numeric Targets
DDTs PCBs Chlordane Toxaphene
Sediments X √√√
Water X X √na
Tissue X X √na
New Sediment Quality Objectives
DDTs PCBs Chlordane Toxaphene
Sediment X X X X
Tissue √√√√
3
Overall the sediment, water and tissue concentrations are lower than ever before.
DDT IN SEDIMENT
4
Policy recommends
85% of samples must
be assessed as
meeting standard
Upper Bay: 5 out of
7 samples (71%)
meets sediment
quality objectives
Lower Bay: 6 out of
19 samples (32%)
meets sediment
quality objectives
SEDIMENT QUALITY OBJECTIVES
Green = meets standards for benthic health
Policy recommends 85% of area must be assessed as meeting standard
Upper Bay: 1 out of 6 samples (17%) meets sediment quality objectives
Lower Bay: 6 out of 9 samples (67%) meets sediment quality objectives
5
LNRHIRLNBRIN
LNBTUB
UNBSDC
UNBJAM
UNBNSB
UNBCHB
SUMMARY OF AVAILABLE TOXICITY DATA
Organochlorine
pesticides not at levels
that cause toxicity
RECOVERY
Fish tissue declining
Sources declining
Regional trends declining
7
0
10
20
30
40
50
60
70
80
Ja
n
u
a
r
y
-
0
8
Ju
l
y
-
0
8
Fe
b
r
u
a
r
y
-
0
9
Au
g
u
s
t
-
0
9
Ma
r
c
h
-
1
0
Oc
t
o
b
e
r
-
1
0
Ap
r
i
l
-
1
1
No
v
e
m
b
e
r
-
1
1
Ma
y
-
1
2
De
c
e
m
b
e
r
-
1
2
Ju
l
y
-
1
3
Ja
n
u
a
r
y
-
1
4
Au
g
u
s
t
-
1
4
TO
T
A
L
D
D
T
(
P
P
B
)
SAMPLE DATE
TOTAL DDT TREND LOWER NEWPORT
BAY
LNRHIR
LNBTUB
LNBRIN
LNRHIRLNBRIN
LNBTUB
REDUCTION OF LEGACY CONTAMINANTS IS OCCURRING THROUGHOUT SOUTHERN CALIFORNIA AND NEWPORT BAY
Total DDTs in Mussels Total PCBs in Mussels
Year Year
Decline rate 100 ppb/yr Decline rate 18 ppb/yr
9
REGIONAL BACKGROUND: FISH TISSUE IS HIGHER EVERYWHERE ELSE
Wh
i
t
e
C
r
o
a
k
e
r
T
o
t
a
l
P
C
B
s
(
µ
g
/
k
g
)
Notes: Data shown were collected within the top 16 cm and between 1998 and 2012. Non-detects set to half the method detection limit. Aroclor samples excluded if congeners were synoptically analyzed. Maximum concentration show for co-located samples.
REGIONAL BACKGROUND: FISH TISSUE IS HIGHER EVERYWHERE ELSE
Wh
i
t
e
C
r
o
a
k
e
r
T
o
t
a
l
P
C
B
s
(
µ
g
/
k
g
)
Notes: Data shown were collected within the top 16 cm and between 1998 and 2012. Non-detects set to half the method detection limit. Aroclor samples excluded if congeners were synoptically analyzed. Maximum concentration show for co-located samples.
PROPOSED APPROACH
Determine methods to demonstrate compliance – targets,
SQO or combination
Show progress to support effectiveness of past and current
management actions, gain credit
Focus on regional trends for these pollutants coupled with
stakeholder actions to demonstrate current level of effort is
sufficient and harbor will get to compliance for OC pesticides
in future without any additional actions
Extend TMDL timeline to allow regional sources and natural
(active) recovery of legacy pollutants in the system and in the
region
12
CONTINUED INVESTMENT BY CITY
Need to get engaged with Regional Board
Support revisions through scientific justification
Situation vulnerable to 3rd parties if it appears like “no
action”
Develop monitoring program to track and defend
(justify) approach and extended timeline for TMDL
compliance
13