Laserfiche WebLink
DISCUSSION <br />Somerset Mine effluent has repeatedly failed the C. dubia Whole <br />Effluent Toxicity (WET) test portion of the facility~s permit to <br />discharge. Each WET test has recorded high alkalinity and <br />conductivity in the effluent and in the B-seam spring water that <br />mires with the effluent prior to de-watering. Therefore, it is <br />suspected that the effluent toxicity may be due to total dissolved <br />solids (TDS) particularly NaHC03. <br />The results of these tests found that mock effluent and mock spring <br />water prepared with NaCl at similar sodium concentrations as that <br />in the effluent and spring water, did not cause as high mortality <br />as the effluent and spring water. However, mock samples prepared <br />with NaHCO;, caused higher numbers of mortality than that seen in <br />effluent and spring water and in mock NACl waters. <br />Mortality was not decreased in any EDTA tests. Also, the results <br />of the metals scans did not indicate a specific heavy metal was <br />present at high concentrations in any of the samples. <br />The above results indicate that the toxicant present in Somerset <br />effluent and the B-seam spring water is not a heavy metal or a salt <br />such as NaCl. However, there is evidence that Somerset Mine <br />effluent toxicity is due to sodium bicarbonate. Results show that <br />sodium in the form of sodium bicarbonate, added to laboratory water <br />at the same concentrations as that found in the effluent and spring <br />water, is very toxic. Past test results also found Somerset Mine <br />effluent toxicity can be removed with the addition of sulfuric acid <br />but not with hydrochloric acid. It is suggested that this is <br />because sodium from sodium bicarbonate may form a non-toxic sulfate <br />compound with the addition of sulfuric acid and a toxic salt (NaCl) <br />with the addition of hydrochloric acid. High concentrations of <br />sodium and high alkalinity found in the effluent and spring water <br />also indicate that sodium bicarbonate may be the cause of Whole <br />Effluent Toxicity. <br />-5- <br />COMMER CIALTESTING & EN GIN EE RING CO. <br />a 65 ~~~ <br />urinal Wai ermarketl For Vou~ Pro~eclion <br />