Off-Grid Photovoltaic System in a Temperate Climate Greenhouse in Virginia
Douglas Mose, Ph.D., and Evans Mandes, Ph.D., College of Science, and James Metcalf, Ph.D., College of Health and Human Services, George Mason University, Fairfax, VA 22030, Tel: 703-993-1068, Fax 703-273-2282, Email: dje42@aol.com

Most buildings require power produced from fossil fuels, the extraction and consumption of which contaminate our environment. The Virginia Center of Basic and Applied Science (CBAS,INC) constructed a building in a remote area as a plant and fish nursery (and living space for staff) operated by solar generated electrical power. Comfortable summer interior temperature is facilitated an open-design 15,000 cu.ft. interior, with ceiling fans, many large windows and doors, and a large sun-screen eave off the 1000 sq.ft. south-facing roof. Comfortable winter interior temperature is possible because the building has no tree-shade, thick well-insulated walls and ceiling, thick cement floor, low ACH, and when necessary, the surrounding forest provides wood stove heat. The energy challenge was to develop a solar powered electrical generating system for year-round use (primarily for lights, fans, pumps, heaters and staff living requirements). On average, the system uses 3-4 kilowatt hours/day. The solar power is captured by 8 100-watt solar panels which during daylight hours serve the building and charge the batteries. The complete system (solar panels, batteries, DC-to-AC inverter) cost about $10,000, about 5% of the total facility cost.

Nitrate Removal from Synthetic High Nitrate Waste by a Denitrifying Bacterium
Student Presenter
Rashmi R. Nair, Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India. Tel: +91-22-23091038, Fax: +91-22-25505151/25519-613, Email: rushnair@gmail.com
Stanislaus F. D’Souza, Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India. Te.: +91-22-25593632, Fax: +91-22-25505151/25519-613, Email: sfdsouza@ barc.gov.in

The present work aims towards isolating organisms capable of treating high nitrate wastewater and optimizing the process for maximum denitrification rate. A denitrifying bacterium strain, isolated from the wastewater of a fertilizer denitrification plant (FDP), was screened from a total of 160 isolated cultures based on its high nitrate removal efficiency. Biochemical tests and 16S rRNA sequence analysis showed the bacterium genus to be Pseudomonas and close to aeruginosa species. The culture on acclimatization to high strength nitrate waste [10000 ppm NO3 (2258 ppm NO3-N)] in a sequence batch reactor, showed complete degradation in a time period of just 1.75 h. The specific nitrate and nitrite degradation rate of the process using the acclimatized culture was further increased by 54.4 % and 15 % respectively on optimizing the process using orthogonal array method. The applicability of this isolate for high rate denitrification process was investigated in a 4 L reactor and the two important enzymes involved in the first two steps of denitrification process, NaR and NiR were assayed. This provided an invitro index of the ability of the cells to reduce nitrate and nitrite. The reactor was run successfully for 2 months without any change in the activity. Studies has now been extended further by using this isolate for denitrification of radioactive nuclear high nitrate wastes, which is a common nuclear problem faced during uranium extraction process.

Influence of Salinity on Uptake and Toxicity of Zinc in the Earthworm Eisenia fetida
Olugbenga J. Owojori, MSc., Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa. Tel: +27 21 808 3471, Fax: +27 21 808 2405, Email: ojart@sun.ac.za
Adriaan J.Reinecke, PhD, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa. Tel: +27 21 808 3471, Fax: +27 21 808 2405, Email: ajr@sun.ac.za
Andrei B. Rozanov, PhD, Department of Soil Science, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa. Tel: +27 21 808 2397, Fax: +27 21 808 4791, Email: dar@sun.ac.za

Salinization of soil is a global problem especially in semi-arid and arid regions. Few studies have considered the influence of salinity on beneficial soil organisms, and their uptake of metals. Recent studies on the development of Biotic Ligand Model (BLM) suggest that cations (at low concentrations), may protect organisms against metal toxicity but effects of these cations at high concentrations remain speculative. In order to assess the influence of salinity on uptake and toxicity of zinc to earthworms, specimens of Eisenia fetida were exposed to zinc for 28 days using OECD artificial soil adjusted with 0 , 2000  and 4000 mg/kg NaCl. Zn was added as ZnCl₂ in a range of concentrations (0, 250, 500, 750 and 1000 mg/kg Zn). The endpoints; mortality, weight change, and internal zinc concentration were assessed at Day 1, 7, 14 and 28 while cocoon production was assessed only at day 28. In the substrates, nitric acid, DTPA and CaCl₂ extractable zinc concentrations were also determined. The results indicated that NaCl increased the availability of zinc in the substrates. Weight, mortality and internal zinc concentrations in the worms were not significantly affected by NaCl and zinc as individual substances, but in combination both had significant effects on all of these parameters. In contrast, cocoon production was significantly affected by increased NaCl and ZnCl₂ as individual substances, and the effects were more severe when both substances were present. The 28- d EC₅₀ for cocoon production was 2020 mg/kg NaCl. The observed increase in toxicity with increased salinity could not be explained fully by zinc accumulation in the tissues of the worm. It is concluded that salinity as a result of increased Na+ has a synergistic effect with zinc in toxicity to these earthworms. The implications in the development of BLM for earthworms are discussed.

Rhizobium tropici, EPS Salt Production as a Function of pH and Growth Media Broth
Kimberly N. Powell, Engineer Research & Development Center, 3909 Halls Ferry Road, Vicksburg, MS 39180, United States, Tel: 601-634-2449, Fax:  601-634-3658, Email:  Kimberly.N.Powell@erdc.usace.army.mil
William Andy Martin, Engineer Research & Development Center, 3909 Halls Ferry Road, Vicksburg, MS 39180, United States, Tel:  601-634-3710, Fax:  601-634-4844, Email:   Andy.Martin@erdc.usace.army.mil
Steven L. Larson, Engineer Research & Development Center, 3909 Halls Ferry Road, Vicksburg, MS 39180, United States, Tel:  601-634-3431, Fax:  601-634-3658, Email:   Steven.L.Larson@erdc.usace.army.mil
Victor Medina, Engineer Research & Development Center, 3909 Halls Ferry Road, Vicksburg, MS 39180, United States, Tel:  601-634-4283, Fax:  601-634-4844, Email:   Victor.Medina@erdc.usace.army.mil
Debraka Williams, Engineer Research & Development Center, 3909 Halls Ferry Road, Vicksburg, MS 39180, United States, Tel:  601-634-2449, Fax:  601-634-3658, Email:  Debraka.Williams@erdc.usace.army.mil

Chemical modifications were made to the extracellular polysaccharide (EPS) produced by Rhizobium tropici ATCC 49672 to produce a dry salt of the polymer that can be transported as a low-weight material and reconstituted using local water sources.  When added to a sandy soil at 0.1% by dry weight, this amendment decreased the hydraulic conductivity of the soil by three orders of magnitude.  The biopolymer salt also strengthens the soil and adds increased flexibility which improves the load bearing and facture resistant properties of the soil.  The production of EPS by a monoculture in reactors is a very effective method of producing large quantities of the biopolymer for such diverse uses as dust control and soil stabilization/erosion control, sequestration of organic and inorganic contaminants, and production of specialty coatings.  These properties make the biopolymer an attractive, “green” alternative to petroleum-based synthetic polymers currently in use for these purposes.  Due to the various possible applications of an extracellular polysaccharide (EPS) salt, optimal conditions in regards to pH and growth media type are investigated to increase production and enhance property characteristics of the biopolymer salt.

Biomonitoring Particulate Accumulation Adjoining Limestone Mining Areas in Walayar Reserve Forest Region Western Ghats, India
Student Presenter
Bharath Prithiviraj and G.N. Hariharan, Lichen Ecology and Bioprospecting Laboratory, M.S.Swaminathan Research Foundation, 3rd cross st., Taramani Institutional Area, Taramani, Chennai 600 113, Tamil Nadu, India. Tel: 91 44 22541698, Fax: 91 44 22541319, Email: lichens@mssrf.res.in, vpbharath@gmail.com

Assessment of limestone dust and its accumulation on native lichen thalli reveals that pollution monitoring in forest areas can be assessed using epiphytic lichens by studying the community level changes and accumulation of elemental content within lichen thalli with data physiological response with photobiont chlorophyll degradation and membrane integrity ratios displaying change to chemical pollutants. The chemical analysis of native lichen thalli will indicate metal accumulation over the lichen’s lifespan (Purvis et al. 2004). Air pollution monitoring associated with limestone quarries and their dust dispersal effects within forest areas was carried out using epiphytic lichens Heterodermia dissecta, Physcia tribacoides, Parmotrema grayanum and Bacidia beckhausii Körber after ecological sampling within the Walayar RF area adjoining the Malabar cements factory, Kerala and ACC limestone mines, Tamil Nadu. The impact of cement dust using lichens within this region was not analyzed prior to this study. This investigation is part of a study initiated in order to understand the impact of cement dust on lichen diversity and its distribution pattern in order to assess the morphological and ultra-structural changes, accumulation of elements and heavy metals within lichen thalli and the photobiont photosynthetic pigment degradation profile as a physiological response to air pollution within select lichen species. The lichen surveys were carried out in the reserve forest areas near the limestone quarry and the cement kiln located within the Walayar valley region, 25 km SW of Coimbatore city, Tamil Nadu, India. Lichen sampling was carried out in locations closer to the cement factory and the limestone mining / blasting area. This study deals with the morphological analysis of lichen species using Environmental SEM confirms that this forest ecosystem located closer to anthropogenic sources of particulate matter is exposed to greater levels of air pollution in this portion of Western Ghats, India.

Identification of Ecosystems Status under Technogenic Impact on Bioindication Data
Valeria V. Stolbova, Ph.D., Radioecology & Ecotoxicology Department, Soil Science Faculty, Lomonosov Moscow State University, Vorobjevy Gory, Moscow, 119992, Russia, Tel: (495) 939-25-08, Email: vstol@soil.msu.ru
Sergey V. Mamikhin, D.Sc., Radioecology & Ecotoxicology Department, Soil Science Faculty, Lomonosov Moscow State University, Vorobjevy Gory, Moscow, 119992, Russia, Tel: (495) 939-50-09, Email: mam@soil.msu.ru

Ecosystems status estimation is obligatory component of integrated monitoring for environmental impact assessment. It is essential to reveal the stages of ecosystem’s degradation such as ecological risk, crisis, and catastrophe in the course of status estimation. Identification of technogenic degradation stages at the level of biogeocenosis is preferably to carry using biotic but not chemical indexes. Biotic indexes indicate the response of biogeocenosis components but not technogenic loads. Objectivity of the assessment is assured with formality of data processing procedure. At present time application of bioindication method is restricted by poor development of formal procedures for interpreting bioindication in quality terms. The formal procedure for diagnostics of ecosystem status is required to provide the isolation of the range of biotic indexes and establish its identity to separate degradation stage of impacted ecosystem.

Tested approaches to bioindication data interpretation referring to quality have been classified and arranged according to increasing their formalization degree for terrestrial, water and soil ecosystems. The existing methods of formal rearrangement of bioindication data is shown to be mainly based on: 1) expert quality estimation, 2) statistical treatment of numerous biotic indexes, 3) complex bioindication combining various system levels of bioindicators, 4) analysis of curves of dose-response relationship and 5) ecological modeling. Practical potentials of the formal approaches and ecological interpretation of their results have been considered.

For practical purposes complex bioindication method is considered to be adequate to definite identification of the status of impacted ecosystems. This method involves appropriate data formalization and consistent ecological interpretation for formal procedure. Technique of biotic data processing with coincidence of the results obtained on superordinate system levels enables to create division by degree of ecosystem transformation. The detection of the biotic indexes values variations on the higher hierarchic level indicates the development of successive ecosystem’s degradation phase.

A Case Study for the Modification of FEMA Base Floodplain Elevations
Christopher R. Trowbridge, LFR Inc., 87 Church Street, East Hartford, CT 06108, Tel: 860-290-9300, Fax: 860-290-9009, Email: Christopher.Trowbridge@lfr.com

The Federal Emergency Management Agency (FEMA) currently regulates floodplain elevations in all US waterways. A local Connecticut town installed a bridge over a brook in order to move two historical buildings for preservation purposes. In order to successfully install this bridge, fill was required in the water channel to allow for proper support of the bridge footings. The addition of the fill resulted in a rise in the floodplain elevation, potentially putting the base of the bridge and the two historical buildings in the base floodplain elevation. In order for the town to receive reimbursement for the bridge and grants for preservation of the historical buildings, they had to demonstrate that the new floodplain elevation would not raise enough to adversely impact the historical buildings or any other existing structures placed along the water channel. A preliminary investigation was conducted prior to submittal of the full request for a Letter of Map Revision (LOMR). The LOMR is the application used to modify existing floodplains through FEMA approval. The preliminary investigation involved construction of three floodplain cross sections; one upstream, one downstream and one at the bridge location. These cross sections, combined with the total catchment area and peak flow intensity for a 100-year storm was used to determine the peak water elevation at each cross section. The results of the preliminary investigation indicate that the fill causes the water levels to rise at the bridge, and gradually returns to normal conditions in the upstream direction. The more detailed LOMR investigation will begin in February of 2008, with completion and review by FEMA by July of 2008. The more detailed investigation will include additional cross sections and the use of the HEC-RAS modeling software to support the findings of the preliminary investigation.

Contamination of Groundwater by Leaking Sewers – Role of the Unsaturated Zone and the Capillary Fringe
J. Hua, University of Karlsruhe, Department of Biology for Engineers and Biotechnology of Wastewater, Am Fasanengarten, D-76228 Karlsruhe, Germany
P. An, University of Karlsruhe, Department of Biology for Engineers and Biotechnology of Wastewater, Am Fasanengarten, D-76228 Karlsruhe, Germany 
C. Gallert,  University of Karlsruhe, Department of Biology for Engineers and Biotechnology of Wastewater, Am Fasanengarten, D-76228 Karlsruhe, Germany, Email: Claudia.Gallert@iba.uka.de
J. Winter, University of Karlsruhe, Department of Biology for Engineers and Biotechnology of Wastewater, Am Fasanengarten, D-76228 Karlsruhe, Germany, Tel: 0049-721-608-2297 or –2696, Email: Josef.Winter@iba.uka.de

On average 25 % of the sewage from urban sewers are lost through leaky sewers, causing soil and groundwater pollution. The hydraulic behaviour of trickling sewage in soil, biological and chemical reactions in the unsaturated zone and the capillary fringe and evolving hazards for the groundwater were investigated.

Simulation experiments on trickling of sewage into the subsoil below leaky sewers were performed in artifical soil or sand cones. Glass columns were filled with fine sand (Ø 0.5-2.0 mm), that allows fast trickling and represents “the worst case” of pollution. Mechanically pre-treated sewage was taken from the domestic sewage treatment plant of Karlsruhe and was trickled through the sand columns.

A beginning colmation was seen after about 20 days of wastewater infiltration into a sand column. The colmation layer increased with time, filtering off the larger particles and leaving through dissolved matter and small partilces, including bacteria. Methane, CO₂ and N₂ gas bubble evolution disturbed the colmation layer and prevented permanently a total colmation. Effluent of the sand columns varied under aerobic and anaerobic conditions, representing changing environmental conditions in the soil, capillary fringe and groundwater.

Most of the COD of the wastewater in the unsaturated soil was eliminated after a trickling stretch of less than 125 cm. About 50 % of the COD was already eliminated in a 2 cm thick organic colmation layer. A little more COD was eliminated under water-saturated conditions. A further COD removal of maximally 5-7 % was observed if effluent of the 125 cm sand columns was trickled to an adjacent 125 cm of nonsaturated sand and its capillary fringe. The trickling rate had a less pronounced effect than the residual BOD-compounds. Even after a trickling stretch of 2.5 m 8-10 % of the COD of raw sewage remained as non-biodegradable compounds, containing (new) humic acid-like and xenobiotic substances, as well as inorganic sewage compounds.

In the center of an anaerobic sewage plume heavy metals are precipitated and immobilized under anaerobic conditions by sulfide steming from sulfate reduction. However, when trickling rates are decreasing and the plume gets aerobic, metal sulfides are reoxidized by aerobic conversion to sulfates and these are dislocated to deeper layers. Metal adsorption was mainly dependent on the pH and the ion properties. Metal ions were adsorbed (and precipitated as sulfides) in aged columns on the biofilm. All metal ions were enriched almost quantitatively in sand columns with the organic particle fraction followed by columns where the sewage was applied. Least immobilization was found in columns through which the soluble fraction of sewage was trickled. 

Aerobic and anaerobic bacteria were reduced by three to four orders of magnitude after 125 cm of trickling distance. The capillary fringe did, however, not hinder bacteria to be washed into the groundwater. Significant growth of aerobic or anaerobic microorganisms occured only in the upper 30 cm of soil.

Biofilm formation influenced hydraulic properties. E. coli and other bacteria (presumably adsorbed or growing in the biofilm) were shifted in the sand layer with time in deeper soil zones. After some months, E. coli was found in the ground water.

The results after 250 cm of trickling distance of sewage in a sandy soil showed that the COD and the nitrogen of the sewage could not be completely eliminated in the sandy soil. Sewage from leaking sewers does pollute primarily the soil by residual heavy metal precipitates and the ground water with soluble organic and inorganic material, including humic acid-like substances . Metal precipitates in soil undergo disssolution under certain conditions and then contaminate the groundwater. Thus trickling sewage pollutes soil and groundwater and creates a risc for groundwater use as a potable water resource.

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