Overview and Current Situation of Groundwater Environment

Groundwater in Xining Basin, shallow, abundant and of good quality, has relatively high degree of development and utilization based on higher degree of hydrogeological research. The amount of underground water resources is calculated based on its total replenishment, which includes rainfall infiltration, surface water replenishment, pedimont lateral recharge (mainly from undercurrent of river bed) and return flow of groundwater abstraction. Surface water replenishment comes from seepage from river channel, canal system and farmland. The phreatic water of river valley in Xining area mainly comes from leakage of surface water bodies and from lateral recharge of underground runoffs of ditches and valleys in bedrock mountain area and rainfall infiltration as well.

(1) Groundwater Environment in Beichuan Area

To understand quality of groundwater environment in Beichuan Area, data in EIA for Beichuan River Plan were referenced and the monitoring was conducted by Xining Environmental Monitoring Station in 2012, within the time inverval for data reference purpose.

Monitoring time and frequency: Groundwater monitoring was conducted by Xining Environmental Monitoring Station for 3 consecutive days from Oct.29 to Oct.31, 2012, with water samples collected once every day.

Monitoring parameters: Totally 10 parameters, incl. PH, TDS, NH4-N, Total Hardness, permanganate index, Zn, Fe, anionic surfactant, coliform and total

Monitoring results: As shown in Table 3.3-5, the results include maximal value, average value, detection ratio, exceedance ratio, multples of average value exceeding the standard. Sites selected for the monitoring are shown in Figure 3.3-1C.

Table 3.3-5 Monitoring Results of Groundwater Environmental Quality

No. Parameters 1＃ Beihai Park

2＃ Taoxin Village

Standard Value

（mg/l，except for pH, coliform and bacteria）

1 pH 7.49~7.63 7.53~7.86 6.5~8.5

2 Total Hardness 550~589 960~996 450

3 TDS 152~198 106~128 1000

4 Fe 0.05~0.06 0.03~0.03 0.3

5 NH4-N 0.237~0.263 0.037~0.066 0.2

6 Anion Surfactant 0.05~0.056 0.058~0.081 0.3

7 Zn 0.02~0.04 0.04~0.04 1.0

8 Permanganate

From the above table, it is clear that among all 10 parameters monitored at No.1 monitoring well at Beihai Park and No.2 monitoring well at Taoxin Village, pH, permanaganate index, Zn, Fe, TDS, anionic surfactant are within limit of the standard, while NH4-N, total bacteria, total coliform and total hardness exceed the standard value, including 100% of exceedance ratio for both total hardness and total bacteria, and 100% of exceedance ratio for total coliform at No.3 monitoring well in Taoxin Village.

The above monitoring results indicate that groundwater in the assessment area has been polluted by pollutants such as total hardness, NH4-N, total coliform and total bacteria. The main reasons for the pollution are arbitrary dumping and pile-up of domestic solid waste and lack of effective sewage collection in the assessment area, and the solid and liquid domestic waste result in pollution through infiltration.

(2) Groundwater Monitoring at Upper Stream of Xichuan and Beichuan River Considering that groundwater in Beichuan Area has parameters of NH4-N, total coliform and total bacteria exceeding the standard, investigations on quality of groundwater at the upper stream of Beichuan and Xichuan rivers were conducted during this EIA for data collection and hence better understanding of groundwater quality in the assessment area. Based on data collected from No.4 water plant and Duoba water plant in Xining for period of 2011 and 2012 (see Table 3.3-6 on the next page for details), in the upper stream of Beichuan and Xichuan River, groundwater quality has all parameters meeting Class-III standard as per Groundwater Quality Standard (GB/T 14848-93), indicating good quality of groundwater in the upper stream of rivers.

Table 3.3-6 Monitoring of Groundwater Quality of Project Area

Water Source

Sampling Time

(YY-MM-DD) PH Total

Hardness Sulfate Chloride Iron Manganes

e Copper Zinc Volatile

2011.02.09 7.67 171 8 8 0.05 0.01L 0.001L 0.02

L 0.002L 0.05L 0.5 1.24 0.003L

2011.06.01 7.70 194 31 10 0.17 0.01L 0.002 0.02

L 0.002L 0.05L 0.5L 1.22 0.003L

2011.08.01 7.72 162 30 52 0.03L 0.01L 0.013 0.02

L 0.002L 0.05L 0.56 1.15 0.003L

2012.02.01 7.71 162 34 10L 0.03L 0.01L 0.05L 0.02

L 0.0005 0.05L 0.5L 1.3 0.003L

2012.06.07 7.86 178 35 8 0.03L 0.01L 0.05L 0.02

L 0.0009 0.05L 0.5L 0.931 0.003L

2012.08.03 7.83 142 21 6 0.005 0.02 0.05L 0.02

L 0.0010 0.05L 0.5L 0.98 0.003L

Duoba Water Plant

2011.02.09 7.45 313 103 50 0.03L 0.01L 0.001L 0.02

L 0.002L 0.05L 0.6 3.08 0.003L

2011.06.01 7.76 348 104 56 0.12 0.01 0.008 0.02

L 0.002L 0.05L 0.64 4.74 0.003L

2011.08.01 7.54 322 90 52 0.03L 0.01L 0.017 0.02

L 0.002L 0.05L 0.56 4.67 0.003L

2012.02.01 7.51 366 97 54 0.06 0.01L 0.05L 0.02

L 0.0009 0.064 0.5L 3.55 0.003L

2012.06.07 7.57 380 94 62 0.03L 0.01L 0.05L 0.02

L 0.0009 0.05L 0.5L 0.931 0.003L

2012.08.03 7.75 336 105 16 0.03L 0.02 0.05L 0.02

L 0.0008 0.05L 0.5L 4.55 0.003L

Standard 6.5~8.5 450 250 250 0.3 0.1 1.0 1.0 0.002 0.3 3.0 20 0.02

Table 3.3-6 (Continued) Monitoring of Groundwater Quality of Project Area

Water Source

Sampling Time (YY-MM-DD)

Ammonia

Nitrogen Fluoride Cyanide Mercury Arsenic Selenium Cadmiu m

Hexavalent

Chromium Lead No. of Fecal Coliform Group (Nr./ L)

Total Dissolved Solid

No.4 Water Plant

2011.02.09 0.025L 0.36 0.004L 0.00001L 0.0017 0.0005L 0.0001L 0.004L 0.001L 1L

2011.06.01 0.025L 0.32 0.004L 0.00001L 0.0008 0.0005L 0.0001L 0.004L 0.001L 1L

2011.08.01 0.025L 0.33 0.004L 0.00001L 0.0006 0.0005L 0.0001L 0.004L 0.001L 1L

2012.02.01 0.025L 0.14 0.004L 0.00002 0.001 0.0005L 0.0001L 0.004L 0.001L 1L

2012.06.07 0.025L 0.09 0.004L 0.00001 0.0009 0.0005L 0.0001L 0.004L 0.001L 1L 162

2012.08.03 0.025L 0.09 0.004L 0.00002 0.0016 0.0005L 0.0001L 0.004L 0.001L 1L 162

Duoba Water Plant

2011.02.09 0.025L 0.49 0.004L 0.00001L 0.001 0.0005L 0.0001L 0.004L 0.001L 1L

2011.06.01 0.025L 0.49 0.004L 0.00001L 0.0005 0.0005L 0.0001L 0.004L 0.001L 1L

2011.08.01 0.025L 0.52 0.004L 0.00001L 0.0016 0.0005L 0.0001L 0.004L 0.001L 1L

2012.02.01 0.025L 0.2 0.004L 0.00001 0.0005L 0.0005L 0.0001L 0.004L 0.001L 1L

2012.06.07 0.025L 0.09 0.004L 0.00001L 0.0005L 0.0005L 0.0001L 0.004L 0.001L 1L 188

2012.08.03 0.025L 0.12 0.004L 0.00001L 0.001 0.0005L 0.0001L 0.004L 0.001L 1L 194

Standard 0.2 1.0 0.05 0.001 0.05 0.01 0.01 0.05 0.05 3 1000

3.4 Current Ecological Situation in Project Area (1) Current Structure of Ecological System

At present, the inland ecological system of the area refers to the flood plain ecological system on both sides of Beichuan River and the urban ecological system on both banks. The ecological environment in the area generally shows the form of suburban agricultural environment. Artificial ecological system is the main form which mainly consists of human, crops and domestic animals, and relatively less other species of animals and plants. For this reason, food chain and food web formed are relatively simple and the ecological system is weak in resisting external interference.

(2) Current Types of Vegetation

At present, the vegetation species in the area are mainly crops cultivated artificially which include certain part of artificially cultivated or naturally growing forestlands. The original vegetation species are destroyed because villagers are building houses and reclaiming farmlands in such area. See figure 3.4-1 for the vegetation forms in the area.

(3) Current Types of Animals

Wild animals in the area are mainly small animals such as rats, rabbits and snakes. Besides wild animals, there are also poultry and livestock such as chicken, cattle and sheep that are artificially raised in the area.

(4) Current Situation of Agriculture

In the area, agriculture is the major industrial structure; the local villagers live basically by growing crops. Remote sensing data show that irrigated land is the main farmland in the area.

Figure 3.4-1 Current Distribution of Vegetation in Beichuan area (5) Current Situation of Soil Erosion

Xining Municipality is located in the transition area between Loess Plateau and Qinghai-Tibetan Plateau with serious water and soil loss, and belongs to the fourth subregion of hilly and gully region in terms of the classification of areas with water and soil loss in Loess Plateau. According to Notification on Zoning of Important Prevention Area for Water and Soil Loss issued by People’s Government of Qinghai Province and map of 3-area zoning for water and soil loss in Qinghai, it is determined that planning area is located in the important treatment area for water and soil loss in Qinghai, with main erosion type being water erosion. The soil erosion modulus is

in the range of 1500~3000t/Km² .a. See Figure 3.4-2 for the current situation of soil erosion in the area.

Figure 3.4-2 Current Situation of Soil Erosion in Beichuan area