50 mg/l.
The draft General Permit reads, "to be eligible for reduced monitoring for copper sulfate use, permittees must have 5 years of water hardness results that are all over > 50 mg/l". In addition to the afore mentioned data demonstrating lower t...↓
The data supports a less stringent hardness level and monitoring period for when chelated copper is used compared with copper sulfate. We propose additional language stating, if chelated copper is being used, water hardness results for one year are needed and those results need to be > 25mg CaCO3/L.
References
Masuda, K., C..E Boyd (1993) Comparative evaluation of the solubility and algal toxicity of copper sulfate and chelated copper. Aquaculture 117:287-302.
Murray-Gulde, C. L., J. E. Heatley, A. L. Schwartzman and J. H. Rodgers Jr. 2002. Algicidal effectiveness of Clearigate, Cutrine-Plus, and Copper Sulfate and margins of safety associated with their use. Environ. Contam. Toxicol. 43:19-27.
Popp, A., Cope, W. G., McGregor, M. A., Kwak, T. J., Augspurger, T., Levine, J. F., & Koch, L. 2018. A Comparison of the chemical sensitivities between in vitro and in vivo propagated juvenile freshwater mussels: Implications for standard toxicity testing. Environmental Toxicology and Chemistry, 37(12), 3077–3085
Riley and Finlayson. 2004. Acute Toxicities of Herbicides Used To Control Water Hyacinth And Brazilian Elodea On Larval Delta Smelt And Sacramento Splittail By. California Department of Fish and Game. Office Of Spill Prevention and Response Administrative Report 04-003
Stauber, J. L. and T. M. Florence (1987) Mechanism of toxicity of ionic copper and copper complexes to algae. Marine Bio. 94:511-519.
Straus, D.L., C.S. Tucker (1993) Acute toxicity of copper sulfate and chelated copper to channel catfish Ictalarus punctatus. J World Aquacult Soc 24(3):390-395.
United States Environmental Protection Agency (2009) Reregistration Eligibility Decision for Coppers. 738-R-09-304. 176 p.
Virginia Cooperative Extension. 2009. Pesticides and Aquatic Animals: A Guide to Reducing Impacts on Aquatic Systems. Publication 420-013. http://hdl.handle.net/10919/48060
WA DOE Supplemental Environmental Impact Statement Assessments of Aquatic Herbicides volume 6: copper
Wagner JL, Townsend AK, Velzis AE, Paul EA. 2017. Temperature and toxicity of the copper herbicide (Nautique) to freshwater fish in field and laboratory trials. Cogent Environmental Science 3:1339386
↓
