Christopher,JM; Philips,ES (1999): Total organic carbon disappearance kinetics for the supercritical water oxidation of Monosubstituted Phenols. Environmental Sciences & Technology, 33(11): 1911-1915.

We oxidized phenols bearing single -CH₃, -C₂Hs, -COCH₃, -CHO, -OH, -OCH₃, and -NO₂ substituents in supercritical water at 460 °C and 25.3 MPa. The observed effects of the concentrations of total organic carbon (TOC) and oxygen on the global disappearance rates for TOC were correlated by using power-law rate expressions. This kinetics study revealed that the rate of TOC disappearance is more sensitive to the oxygen concentration than is the rate of reactant disappearance. Additionally, the rate of TOC disappearance is always slower than the rate of reactant disappearance, with the ratio of these rates ranging from 0.10 to 0.65 for the different phenols at the conditions studied. The rates of roc disappearance during supercritical water oxidation (SCWO} of these substituted phenols varied by nearly 2 orders of magnitude; showing significant effects from both the identity and location of the substituent. These substituent effects are greater for TOC disappearance kinetics than for reactant disappearance kinetics. Additionally, all of the substituted phenols exhibit faster TOC disappearance rates than does phenol. Accordingly, phenol is a good "worst case" model compound for SCWO studies. The pronounced substituent effects for TOC disappearance rates indicate that the oxidation of a common refractory intermediate is not an important feature of the SCWO networks for these phenols at the conditions studied.

Das,S; Mehta,BC; Das,PK; Srivastava,SK; Samanta,Sk (1999): Sources of high fluoride in ground water around Anugul, Dhenkenal, Orissa. Pollution Research, 18(1): 21-28.

Hydrogeological investigations were carried out in the area around Anugul, Dhenkenal district, Orissa in the wake of the reported fluoride contamination of ground water. In all 163 numbers of dug wells and 10 numbers of shallow tube we11s were monitored. Water samples were collected and analysed from selected dug wells, tube wells, major rivers, tanks, effluent channels, ash pond etc. The ground water occurs under water table condition in the weathered residium and circulates through deeper fractured zones. High fluoride content (more than 1.5 mg/L) was recorded in the shallow ground water in scattered pockets, both in the basement complex and in the Gondwana sedimentaries. However the fluoride content in the ground water in the immediate vicinity of the effluent channels and the disposal pond of NALCO smelter plant was found within permissible limits. Hydrogeochemical studies point towards a possible geological source of high fluoride content in the ground water of the area.

Elampooranan,T; Rengarj,S (1999): Ground water quality in Naggapattinam and Thanjavur Districts. Indian Journal of Environmental Protection, 19(4): 255-259.

Ground water quality is studied by systematic collection and analysis of samples, which enable us to properly manage the resources. In this study an attempt is made to assess the groundwater quality in the Thanjavur and Nagapattinam districts of Tamil Nadu. The study was carried out by collection of ground water samples from about 46 wells located in these districts. The samples were collected during the month of February 1997 and were analysed for EC, pH, TDS, TH, Na⁺, K⁺, Ca²⁺, Mg²⁺, Fe²⁺, CO₃^2-, HCO₃^-, Cl^-, SO₄^2-, NO₃^- and F^-. The pH of all the water samples were around 7 and occasional by alkaline. In about 20 wells the recommended limits for drinking water quality standard is exceeded in one or the other parameters. In general the ground waters of this area are suitable for irrigation.

Ganguly,T; Kumar,B; Sen,AK; Bhunia,AB (1999): Assessment of water quality of Damodar river through comparative analysis of bio-indicators and physicochemical determinants. Journal of Environment & Pollution, 6(2&3): 189-196.

The paper deals with the water quality of Damodar river using bioindicators as quality determinants. The study was conducted duirng May 1994 to February 1995 in three phases covering biologically active period. In addition to the scoring of biological indicators, some selected background physiochemical parameters were also monitored.

The state of water quality as revealed through the comparitive analysis of biological scores and physiochemical parameters have been discussed.

Graetz,DA; Nair,VD; Portier,KM; Voss,RL (1999): Phosphorus accumulation in manure-impacted spodosols of Florida. Agricualture, Ecosystems and Evironment, 75: 31-40.

Accumulation of phosphorus (P) in soils receiving long-term application of manure has been linked with degradation of water quality in nearby streams and lakes. The objective of this research was to determine the amounts and depth distribution of phosphorus (p) in Florida Spodosols used for dairies and beef ranches, and relate them to various soil chemical parameters. Land areas of both active and abandoned dairies were sampled based on estimated cattle density. High catlle-density areas of both the active and abandoned dairies, i.e., the intensive and holding areas, had mean total phosphorus(TP) concentrations in the surface horizon (A) of 2500 mg/kg and 750 mg/kg, respectively compared to 30 mg/kg in the native area. i.e., an area largely unimpacted by animals and humans. The dairy and beef cattle pastures and the forage areas (low cattle density areas) had a mean TP concentration of 114 mg/kg. Concentrations of TP in the E, Bh, and Bw soil horizons were also greater in the high cattle density areas than in the low cattle density areas or in the native areas. Water-soluble P concentrations (WSP) were higher in all soil horizons of the high cattle density areas compared to the low cattle density areas and the native areas. Water-soluble P concentrations in the surface horizons of the high cattle density areas averaged 3.4% of TP which suggests that a substantial amount of P could be transported either vertically or laterally with subsurface drainage. Double acid-extractable P (DAP) concentrations, which could be used as an indicator of potentially leachable P, were considerably higher than WSP concentrations and averaged (over all land-uses) 42, 44, 57 and 31% of TP for the A, E, Bh, and Bw horizons, respectively. The association of WSP, DAP, and TP with the soil chemical parameters measured in this study showed a varied relationship with double acid-extractable Ca and Mg and oxalate-extractable Fe and Al. Overall, these results show the accumulation of large amounts of P in high cattle density areas. Significant amounts of this P were in forms that are potentially leachable, i.e., WSP and DAP. Higher concentrations of all P forms in the subsurface horizons (E, Bh, Bw) of high cattle density areas confirm the downward transport of P in these manure-laden Spodosols.