Application of Sediment Quality Criteria for Metals to a Montane Lotic Ecosystem: Field Validation During Reclamation of a Copper Mine Causing Acid Mine DrainageEPA Grant Number: R826199
Title: Application of Sediment Quality Criteria for Metals to a Montane Lotic Ecosystem: Field Validation During Reclamation of a Copper Mine Causing Acid Mine Drainage
Investigators: Meyer, Joseph S. , Lockwood, Jeffrey A. , Rockwell, Richard W.
Institution: University of Wyoming
EPA Project Officer: Chung, Serena
Project Period: April 1, 1998 through March 31, 2001 (Extended to September 30, 2002)
Project Amount: $449,558
RFA: Contaminated Sediments (1997) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Hazardous Waste/Remediation , Land and Waste Management
Test if a method for deriving sediment quality criteria (SQC) for metals proposed by Ankley et al. (1996; Environ. Toxicol. Chem. 15:2056-2066) is valid for use in a montane stream receiving acid mine drainage, before and during site remediation.
We will analyze acid volatile sulfide (AVS), simultaneously extracted metals (SEM), and organic carbon (OC) in sediments, with respect to spatial (distance from metal source), seasonal, and annual (pre- and post-reclamation) gradients in Haggarty Creek, which receives metals discharge from a former copper mine in southeastern Wyoming. We will also analyze (1) important water quality parameters (pH, alkalinity, major cations and anions, total and dissolved OC, and total and dissolved Cd, Cu, Ni, Pb and Zn) in interstitial waters and stream waters and (2) several biological repsonses to metals pollution (benthic insect community structure, and in situ toxicity and bioaccumulation of metals). Based on the physical and chemical data and on dose-response relationships determined in the laboratory for three benthic insect species exposed to the five metals, we will then use the four no-effect criteria proposed by Ankley et al. (1996) to predict whether the sediment at each of the five metal-polluted sites on Haggarty Creek and at a reference site (a) passes the SQC screening or (b) appears to be unacceptably contaminated. Those predictions will be compared to observed biological responses to evaluate the validity of the proposed method for deriving SQC for metals when it is applied to hydrologically dynamic, montane stream systems. We will also compare the biological responses to water quality criteria (WQC) calculated for the stream water.
Because the waters of Haggarty Creek are well oxygenated, we expect the AVS content of sediments in the pools to be relatively low. Thus, we expect OC will play at least as large a role in controlling metal bioavailability as does AVS, especially because Cu (the dominant pollutant in Haggarty Creek) has a relatively high affinity for OC. If exposures of benthic insects to metals in this type of stream are controlled by sediments, the proposed AVS-and-OC criterion should be a good predictor of sediment quality, and bioaccumulation of metals should correlate well with interstitial-water concentrations. But if concentrations of dissolved metals in the water above the sediments are more important in determining the exposure, WQC might be better predictors of in situ toxicity, benthic community structure and bioaccumulation than are SQC. Most likely, the result will lie between these two extremes, with WQC being more important in the higher-elevation reaches and earlier in the season and SQC being more important in the lower-elevation reaches and later in the season.