Step 1: Identification and Preliminary Screening of Hot Spots

3.2. Step 1:  Identification and Preliminary Screening of Hot Spots

In Step 1 the NHSE compiled a full list of Hot Spots for each country based on information available and shortened this list to a manageable number of Hot Spots using the screening method.  If too few or too many Hot Spots passed through the screening method, the parameters were adjusted until a manageable number of Hot Spots were identified for further assessment (Step 2).

For each country, the NHSE compiled a list of Hot Spots based on the guidance provided by the definition.  The Hot Spots were selected from information available in environmental monitoring records of each country and from the knowledge and experience of the NHSE.

Decreasing the number of Hot Spots to a more manageable number for detailed scrutiny was important given the constraints of the project. For the purpose of this report, the following number of Hot Spots were selected for each country:

- Belarus: 50 to 100 Hot Spots

- Russia:  50 to 100 Hot Spots 

- Ukraine: 100 to 200 Hot Spots

Ukraine’s larger number of Hot Spots reflects their greater portion of the basin in terms of industry, population and land area.

Numerical criteria (such as contaminant loadings released from the Hot Spot), and the knowledge of NHSE, were used to screen the Hot Spots to arrive at a manageable number for in-depth assessment. Numerical criteria were adjusted to arrive at the appropriate number and were selected to correspond with data used in each country according to format and availability.  The parameters used as indicators were selected based on their availability. For example, most municipal sewage treatment plants measure Biochemical Oxygen Demand (BOD) in effluent discharges and therefore BOD was selected for this sector, while one of the heavy metals was selected as the indicator for the industrial sector.

For preliminary screening, the “effective mass of contaminant” methodology, which was developed for the characterization of different discharges (their quantity and toxicity), and is based on the “toxic equivalent” concept, was employed.  The “effective mass of contaminant” derived for a discharge was used for the comparative assessment of different contaminant discharges where multiple contaminants were involved.  The Hot Spots yielding the highest “effective mass of contaminant” were promoted to Step 2 for more detailed evaluation. 

The method made use of existing contaminant loading estimates available in the State Statistical Database (2TP – “Vodkhoz”), collected for most dischargers in each of the three countries during the period from 2000 to 2002. 

Calculation of the effective mass of contaminant for “Hot Spot X”(M_X) was based on two parameters: mass of discharged pollutant “i” (m_i), and relative toxicity of pollutant “i”, defined by the coefficient of toxicity, A_i.  The coefficient of toxicity, A_i, was calculated on a relative basis to the toxicity of ammonium sulphate which has a Maximum Permissible Concentration (MPC) value of 1 mg/L* :

For example,

for formaldehyde, A_i = 4  since MPC_formaldehyde = 0.25 mg/L*,

for ammonium perchlorate, A_i = 125  since MPC _{ammonium perchlorate} = 0.008 mg/L*.

Note:  * State Surface Water Quality Standards (Fishery) for all three countries.

The formula for calculating the “effective mass of contaminant i” for a discharge is given by the following:

Mi (tonnes/year)  =  A_i (dimensionless)  x m_i (tonnes/year)

Masses of discharged pollutants by individual discharger for a broad range of components (m_i) are stored in the Database “2TP – Vodkhoz”.  Values of Maximum Permissible Concentrations (MPC_i) for different components were found in the State Surface Water Quality Standards (Fishery).

The total effective mass of discharged contaminants for “Hot Spot X”(M_X) was calculated as the sum of the effective masses of discharged individual contaminants:

        M_X  = å M_i

Values of M_X for individual Hot Spots were used as score values for the preliminary screening and preliminary ranking of all the Hot Spots, as a basis for selecting those to go forward to Step 2.

For multi-point sources of contamination, such as those associated with large industrial or municipal complexes, the effective mass of contaminant was assessed using the following formula, which sums multiple point sources:

åⁿ M_i = M₁ +  M₂ + …. + M_n

It was at the discretion of the National Experts whether there was any merit in aggregating multiple discharges in this manner.  The decision partly depended on whether mitigation could be applied over several sources and whether a “bankable” project could be identified.

Being a simple system, the numerical screening could leave out substantial sources of contamination known to the NHSE.  In addition to the above methodology, the preliminary screening was augmented with additional criteria designed to ensure Hot Spots associated with most of the major economic sectors were included and that there remained flexibility to promote some Hot Spots based on the professional judgement of the National Experts.  This recognized that some significant Hot Spots did not meet the preliminary screening.  These additional criteria for promotion to Step 2 are provided below (Table 3.1).

Table 3.1 : Hot Spot Promotion Criteria For Preliminary Screening

 *     Actual numerical values were adjusted based on data availability, “watershed” defined on a country-specific basis given each country carried out screening independently.

**      Municipal Sector promoted on the basis of BOD and Total Phosphorus loading which served as surrogates for other potential contaminants in municipal            discharges.  Industrial Sector used parameters for which reasonably good watershed loading inventories were available.

***     Focused on livestock operations since fertilizer/pesticide issues are more readily addressed through implementation of Best Management Practices.

Next: Step 2: Detailed Evaluation of Hot Spots

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