Technical Bulletins

Technical Bulletins are listed on this page by year of publication, with the most recent titles appearing at the top of the list. To select a different year, choose from the dropdown list and then click View.

Displaying Documents for Year

Technical Bulletin No. 1044: Evaluation of Escherichia coli (E. coli) Measurement Methods When Applied to Woodyard Runoff

PDF , Source: Technical Bulletins Published: 05/2017 View Abstract

Abstract: The purpose of this study was to characterize the bacteriological composition of woodyard runoff and assess the reliability of Escherichia coli (E. coli) measurement methods when applied to waters derived from this source. The study was conducted on five runoff samples collected during rain events from woodyard areas within pulp and paper mills or wood products facilities where there were no known sanitary contributions. The E. coli analytical methods employed included EPA Method 1603 membrane filtration (MF), Colilert enzyme substrate (ES) at the method-prescribed incubation temperature of 35°C, and Colilert modified with an incubation temperature of 44.5°C. Vitek biochemical species testing was conducted to characterize the bacteriological composition of woodyard runoff and assess potential interferences with the E. coli analytical test methods. Levels of E. coli in woodyard runoff samples ranged from 218 to 8200 counts/100mL. However, study results indicated that none of the analytical methods were ideal for measuring E. coli in woodyard runoff because of high rates of interferences from concurrent growth of other bacteria. Species testing data from all sources showed that E. coli strains were confirmed 65% of the time using MF, 67% of the time by ES when incubated at 44.5°C, and 43% of the time by ES when incubated at 35°C. The remainder represented other species of bacteria or false positive identifications. The difference in ES E. coli confirmation may have been due to inhibited growth of non-thermotolerant background bacteria at the higher incubation temperature, which was illustrated by a difference in the diversity of species identified at the two temperatures.

Technical Bulletin No. 1043: Summary of Full Dilution Series Whole Effluent Toxicity Test Results in Modern Pulp and Paper Treated Effluents

PDF , Source: Technical Bulletins Published: 04/2017 View Abstract

Abstract: NCASI solicited its member companies for bioassay data acquired for tests that utilized a full dilution series of effluent exposures (0 to 100% effluent). The final data set included bioassay results from 22 mills representing 12% of production in the US. All raw data acquired were audited to verify that the bioassay criteria established in EPA methods were met. Trends in acute and chronic bioassay responses for fathead minnow (Pimephales promelas) and waterflea (Ceriodaphnia dubia) were examined for data collected from 1997 to 2011. Patterns between acute and chronic responses and water quality parameters including conductivity, pH, alkalinity, hardness, and ammonia were investigated. Of the 64 bioassays conducted by 11 mills for fathead minnow since 1998, acute toxicity (no observed effect concentration, or NOEC <100%) was observed only four times for organisms exposed to 100% pulp and paper mill biologically treated effluents. Chronic responses as assessed by fathead minnow larval growth occurred more frequently; six out of 64 tests reported an inhibition concentration (IC25) <100% (only two within the last ten years). Acute and chronic responses were encountered more frequently in 100% effluent when assessed using the C. dubia bioassay. Acute toxicity (NOEC <100%) was observed in 12 of 158 tests, and chronic toxicity (IC25 <100%) was observed in 55 of 153 assays reviewed. Examination of trends for acute and chronic bioassay results and conductivity, pH, alkalinity, hardness, and ammonia indicate that conductivities >2500 µohm/cm and alkalinities >480 mg/L correlated with increased bioassay responses in some effluents. KEYWORDS bioassay, Ceriodaphnia dubia, compliance, fathead minnow, mixing zone, Pimephales promelas, reproductive effects, wastewater, waterflea, whole effluent toxicity

Technical Bulletin No. 1042: Greenhouse Gas Aspects of Using Forest Residuals for Energy Production in Forest Products Facilities

PDF , Source: Technical Bulletins Published: 04/2017 View Abstract

Abstract: This study examined the life cycle greenhouse gas (GHG) benefits of using forest residuals for energy production within the forest products industry. Two product systems were compared: a product system in which the forest residuals are burned for energy in a forest products industry facility (biomass energy system), and a product system in which the forest residuals are left to decay or burned in the forest and fossil fuels are used instead to generate an identical amount and form of energy (non-use system). For each residual type, various scenarios were evaluated, including one (the reference scenario) representing the industry average conditions. Moreover, a variety of parameters in the analysis were subjected to sensitivity analyses. Results are presented both for the case where the benefits of fossil fuel substitution are included as well as for the case where they are excluded, in which case, only the fate of the biogenic GHGs in both the biomass energy and non-use systems is considered. In the reference scenario, using residuals for energy produced GHG emissions impacts over 100 years, not including biogenic CO2, that were 92% lower than those from a system disposing of the residuals and using fossil fuels for energy. Even when the differences in biogenic CO2 between the biomass energy system and non-use system were included in the analysis, the GHG emissions for the reference scenario were lower in the biomass energy system by 75.7 kg CO2E/GJ when compared to the non-use system. In the reference scenario, the benefits from using forest residuals to displace fossil fuels start to be seen essentially immediately. Monte Carlo simulations indicate that while there is uncertainty in these findings, there is little doubt that there are net reductions in GHG impacts associated with using forest residuals to displace fossil fuels.

Displaying Document for Year