Determination Cadmium and Lead Pollution Resources of Ardabil Plain Underground Waters

Underground water is among the most important sources of drinking water. The aim of this study was to determine the concentrations of heavy metals (cadmium, lead) in providing plain of Ardabil in 2015. This study was cross-sectional, drinking water samples from 100 wells were prepared according to standard procedures. The dimensions of 350 × 350 meter grid station via a station in the network were determined by atomic absorption spectrometry AAS analysis of samples. The data obtained were analyzed using SPSS software. The average concentrations of lead, cadmium in groundwater wells in the area were also studied. The mean concentrations measured in the majority of groundwater wells in the plain of Ardabil lower than the allowed amount were designated according to a national standard.


Introduction
Population growth and rising living standards in many countries resulted in increased demand for various uses of underground water for agriculture, industry, and urban construction.Less pollution of underground water due to the talent as well as a large storage capacity compared to surface water is considered as an important source of water.An increase in electrical conductivity and concentrations of sodium, chloride, sulfate, and nitrate in groundwater is mostly due to human activities such as farming operations, intensive use of fertilizers, water, and industry.Infected surface increases the amount of TDS [1].Unfortunately, because of the invisibility of many people about the importance of ground water, the harmful effects of environmental pollution on them are not aware [2].In the present society, not only water quantity but also water quality attention and research have proven that many diseases are caused by poor quality water.Substances that are potentially harmful to the consumer should be limited and those substances which can affect public acceptance of water should be controlled [3] [4].Heavy metals including considering the importance of environmental pollutants have attracted attention in scientific communities.Heavy metals in food and tissues of organisms use the food [2].Heavy metals naturally in groundwater resources due to geology and soils are found in small amounts [3] [4].Underground water pollution caused by agricultural operations is not a new phenomenon.High consumption of fertilizers in order to achieve maximum agricultural production increased nitrate in groundwater and endangered human health.So with the use of nitrogen fertilizers, a substantial amount of them are underground water.High nitrate concentrations are harm to human health and aquatic animals [5].According to [3], as the concentration of heavy metals (Cu, Cd, Pb) in drinking water in Mashhad had expressed heavy metal compounds through the various imported water sources [6]- [10].

The Introduction of the Study Area
The plain with an area of 95 thousand hectares in the high plateau is between the mountain and into plain packages.Its height is about 1350 meters from all four sides surrounded by mountains, fields and alluvial deposits of eroded mountains surrounding the basin are closed.Plains due to having proper thickness of sediments and soil quality and numerous rivers, the perfect place for farming activities and production of agricultural products, particularly cereals and potatoes is.This plain, with the ground water and in the last half century has long been considered the most important source of water supply for agriculture, industry, and urban and rural drinking.The aquifer until the last two decades, the number of wells and semi-limited and consequently the withdrawal of ground water level were very low.62 years later and with regard to agricultural development in the region and also and Ardabil urban sprawl and population growth, water extraction from aquifers has been increased for various uses [9] in addition, the network size is 350 in the 350 meters.Also sampled in two seasons of dehydration and over hydration and there is one sample per pixel.Sampling in the summer time months in August and in May 2015 was conducted in the spring.Chemical analysis results in Excel as a database was saved.Position wells were recorded using GPS to map production.Also in this study to analyze the data aggregated statistical software spss test, ANOVA and T-test was used (Figure 1).

Results
Results of the study data obtained from sampling at 100 stations in Ardabil plain dry and wet seasons in 2015 from ground water Table 1 is provided.
The station that was detectable amounts of lead and cadmium in the comparison chart was prepared with the Iranian standards (Diagram 1, Diagram 2).
The results of analysis of variance showed Lead parameters (Table 3) that the stations studied; there was no   significant difference in the level of 1%.The comparison showed that the average stations (Table 4) stations 87 and 88, respectively, with an average of 0.042 and 0.03, 958 mg had the highest infection rates were higher in statistically class stations No. 26, 27, 60, 61, 62 and 99 with a mean of zero ppm were ranked the lowest.
For comparison Lead and Cadmium parameter values in spring and summer paired samples test were used in this experiment.The results showed that compared pairs of heavy metal lead and cadmium summer statistically significant difference was observed in 1% probability level (Table 5).Cadmium and cadmium spring summer pairs well with a statistically significant difference in the level of 1 percent.
For measurements with national standard values were used in this experiment One-Sample Test.The results showed that in both heavy metals lead and cadmium in both summer and spring, there was a statistically significant difference at the 1% level (Table 6).

Conclusions
Cadmium spring is also based on national standards and EPA (0.005 ppm) lower than standard and cadmium contamination exists.

Diagram 2 .
Comparison of cadmium with the Iranian standards.

Table 1 .
Concentration of heavy metals cadmium and lead during dry and wet seasons in the plains of Ardabil.

Diagram 1 .
Comparison of the lead with the Iranian standards.

Table 2 .
Analysis of heavy metal cadmium in the plain of Ardabil in 2015.
** Significant at the 1% level shows.

Table 3 .
Analysis of heavy metal lead in the plain of Ardabil in 2015.

Table 4 .
Comparison of measuring heavy metals lead and cadmium of Ardabil plain Duncan (ppm).

Table 5 .
Test paired samples test for heavy metals lead and cadmium contamination of ground water in the spring and summer in Ardabil plain.

Table 6 .
Paired samples test for heavy metals lead and cadmium contamination of ground water in the spring and summer in Ardabil plain.