Benthic invertebrate response to heavy metal contamination in the

Panther Creek drainage (Idaho): A case study using McQuire’s Metal

Tolerance Index (MTI)

Gary T. Lester – EcoAnalysts, Inc., Moscow, Idaho

Karen Kuzis – Kuzis Consulting, Boise, Idaho

Purposes:

- Give a brief description of the metal tolerance index (MTI)

- Give an overview of the Blackbird mine and associated water quality issues

- Discuss the MTI response to copper during a baseline study conducted last fall.

OVERVIEW OF THE MTI

McGuire’s Metal Tolerance Index (MTI) was developed using benthic invertebrate communities and associated metal data (copper) in Montana’s Clark Fork River

Calculated as a weighted average of tolerance values assigned to each species (similar to HBI)

Score ranges from zero (highly intolerant) to ten (highly tolerant)

0-3 = no impact; 7-10 = significant impact; 3-7 = ???

OVERVIEW OF THE MTI (CONTINUED)

- The index has not been published in a peer-reviewed journal

- The index has been criticized for lack of peer review

Blackbird MineBlackbird Mine

Located 20 miles SW of Salmon, ID in the Salmon NF

Currently inactive

Mined from 1900 – 1982; most active from 1949 – 1967

Mining operations have created 10 miles of tunnels, 4.8 million tons of waste rock, 2 million tons of tailings, numerous adits and portals

Tailings originally dumped directly into Blackbird Creek until 1950’s, after which tailings were dumped into an impoundment

Blackbird Mine (continued)Blackbird Mine (continued)

In 1982 a water treatment facility brought online to treat discharge from several adits that drain into Panther Creek.

Several sources still contaminating surface waters in the area

Metal Contaminants Present in Surface Metal Contaminants Present in Surface Waters:Waters:

ARSENIC

COBALT

COPPER

MANGANESE

ZINC

NICKEL

NATURAL RESOURCE USES:NATURAL RESOURCE USES:

Panther Creek historically served as spawning and rearing for Chinook and Steelhead

Anadromous runs dropped sharply following development of the mine

In 1954 fish kills of salmon, steelhead, trout and whitefish occurred – believed related to acid releases from the mine

Currently, aquatic biota are either non-existent or severely damaged in Meadow, Bucktail, SF Big Deer and Big Deer Creeks

THE STUDYTHE STUDY

A proposed expansion for a cobalt mine requires a pre-operation baseline inventory.

On August 17-18, 2001 benthic macroinvertebrates were collected from the following locations:

Sampling Stations:Sampling Stations:South Fork Big Deer Creek

SF-3 Above Bucktail Cr. SF-2 Below Bucktail Cr.

Sampling Stations:Sampling Stations:Big Deer Creek

BD-5 Above SF Deer Cr. BD-4 Below SF Deer Cr.

Sampling Stations:Sampling Stations:

Panther Creek (no photos available)

FIELD METHODSFIELD METHODS

Benthic invertebrates collected using modified Hess, 500 micron mesh, 0.10 meters sq.

3-Hess composite (across a transect) in riffle habitat

3 riffles sampled per site (3 reps/site)

Total of 0.9 meters sq. sampled at each site

LAB METHODSLAB METHODS

Fixed count/known area subsampling approach (500 count) using a modified Caton subsampler

Invertebrates identified to genus/species where possible including Chironomidae and Oligochaeta

RESULTS

Water Quality – Dissolved CopperWater Quality – Dissolved Copper

0.0004

0.0789

0.0017

0.0202

0.0025

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

SF-3 SF-2 BD-5 BD-4 P1 P2

Mea

n D

isso

lved

Cu

(m

g/l

, n

=5)

TOTAL DENSITYTOTAL DENSITY

0

2000

4000

6000

8000

10000

12000

14000

SF-3 SF-2 BD-5 BD-4 P-1 P-2

Den

sity

(#/

squ

are

met

er)

TAXA RICHNESS AND EPT TAXA RICHNESS AND EPT RICHNESSRICHNESS

43

12

60

32

5444

21

4

27

12 17 12

0

20

40

60

80

SF-3 SF-2 BD-5 BD-4 P-1 P-2

Tax. Rich. EPT Rich.

% Dominance (3 taxa% Dominance (3 taxa))

0

20

40

60

80

SF-3 SF-2 BD-5 BD-4 P-1 P-2

THE DOMINANT CRITTERSTHE DOMINANT CRITTERS

Micropsectra sp. Baetis bicaudatus Pagastia sp.

Diamesa sp. Pagastia sp. Baetis bicaudatus

SF-3 SF-2

THE DOMINANT CRITTERSTHE DOMINANT CRITTERS

Heterlimnius sp. Cinygmula sp. Stempellinella sp.

Pagastia sp. Orthocladius

(Orthocladius) sp. Orthocladius

(Euorthocladius) sp.

BD-5 BD-4

THE DOMINANT CRITTERSTHE DOMINANT CRITTERS

Baetis tricaudatus Cladotanytarsus sp. Optioservus sp.

Baetis tricaudatus Optioservus sp. Cladotanytarsus sp.

P-1 P-2

Taxa eliminated or reduced:Taxa eliminated or reduced:

SENSITIVE MAYFLIES

CHIRONOMIDAE IN THE TRIBE TANYTARSINI

MTIMTI

0

1

2

3

4

5

6

7

8

9

10

SF-3 SF-2 BD-5 BD-4 P-1 P-2

MTI vs. Dissolved Copper*MTI vs. Dissolved Copper*

0

1

2

3

4

5

6

7

8

9

10

SF-3 SF-2 BD-5 BD-4 P-1 P-2

0.0004

0.0789

0.0017

0.0202

0.0025

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

SF-3 SF-2 BD-5 BD-4 P2 P1

Mea

n Di

ssol

ved

Cu (m

g/l,

n=5)

R-squared = 0.809, n=5

*No copper data at P2

MTI Dissolved Cu

MTI vs. HBIMTI vs. HBI

4.493.84

4.45

3.364.2 3.86

0

1

2

3

4

5

6

7

8

9

10

SF-3 SF-2 BD-5 BD-4 P-1 P-2

MTI

HBI

R-squared = -0.597, n=6

TOLERANCES TOLERANCES CANCAN DIFFER SIGNIFICANTLY FOR DIFFER SIGNIFICANTLY FOR ORGANIC VS. METAL CONTAMINANTS!!!ORGANIC VS. METAL CONTAMINANTS!!!

HBI MTICinygmula sp. 0 0

Baetis bicaudatus 2 4

Heterlimnius sp. 3 3

Pagastia sp. 1 9

Diamesa sp. 5 9

Orthocladius sp. 6 5

Micropsectra sp. 4 1

Rheotanytarsus sp. 6 1

Stempellina sp. 2 0

Stempellinella sp. 4 1 (suggest)

Tanytarsus sp. 6 3

Parting Shots:Parting Shots: In this case study the MTI was useful in tracing the

impact of metals as contaminated water flowed from headwaters to Panther Creek

The MTI shows promise as a diagnostic tool for stressor identification (metal contamination), although a more rigorous evaluation is suggested

In addition to EPT, Chironomidae are useful bioindicators of metal impacts when identified at least to genus level.

The MTI was negatively correlated with HBI

Parting Shots (continued):Parting Shots (continued): The next generation of bioassessment tools is focusing

on impact source determination (stressor identification)In order to develop these tools, we can help by having our invertebrate samples accurately identified to lowest practical level

In addition, good physical and chemical data collected with invertebrate samples over a range of conditions will be extremely helpful

Over time, enough real-world data will be collected to develop the associations necessary to assign accurate tolerance values to each taxon (e.g. Brandt, Relyea)