New Hanover County Landfill Leachate Treatment Facility

Trevor SmithShannon AlexanderKelly AbbottCourtney JenkinsCarol Ann Dulin

Strategy/ Goals Determine if the New Hanover County Landfill Treatment

Facility is in compliance with the state laws, regulations and its NPDES permit.

Develop a method of determining compliance including:

- Create a QA/QC plan for sample credibility including chain of custody, photo documentation of YSI & turbidity readings, Photo documentation of facility treatment plant.

- Research of past permitting and violations

- Conclude with a determination of if the Leachate Treatment Facility is in compliance with permitting applications.

QA/QC Plan Developed a written documented chain of custody for all

leachate samples

Delineated responsibilities among team to insure quality control- Trevor Smith - Field Sampling, YSI, Turbidity - Shannon Alexander - Written documentation/ Pictures- Kelly Abbott - Picture Documentation- Courtney Jenkins - Video recorded sampling process- Carol Ann Dulin - Data recording/ Photography

Field Sampling Methods Instruments and equipment

used for field sampling:

YSI-80: Measured:

- Dissolved Oxygen mg/L

- Conductivity µS/cm

- Salinity ppt

Field Sampling Methods Instruments and equipment used for field sampling:

Turbidity Meter: Measured:

-Measured solids in the leachate liquid by the reflection of light through the meter and determining the concentration in particles per thousand (ppt).

Data Findings

EnteringRetention Digester

Manhole (to CFR)

EnteringWetland

After Wetland

Temperature (°C) 23.1 22.1 22.2 22.5 21.4

DO (mg/L) 0.8 5.75 4.16 1.73

DO (%) 0.7 66 48.6 53.5

Conductivity(µS) 11.36 10.24 10.14 6.68 4.7

Salinity (ppt) 6.7 6.2 6.1 3.9 1.2

Turbidity(NTUs) 21.2 133.7 11.11 16 2.85

BOD DataSample Location

Sample Bottle #

BOD5 (mg/L) over 5 days

Collector/ Handler

Manhole(post-treatment)

#112 30.3 mg/L Kelly Abbott

Wetlands(post-treatment)

#104 3.07 mg/L Carol Ann and Trevor

Standards

Effluent Characteristics

Discharge Limitations:Monthly Avg. Daily Max.

Flow 0.050 MGD ---

BOD, 5 Day, 20 °C

30.0 mg/L 45.0 mg/L

TSS 30.0 mg/L 45.0 mg/L

Sampling Locations Leachate entering Retention pond:

Sampling Locations Digester

sampling:-Turbidity sample-Conductivity-Salinity

Sampling Locations Manhole>>to

Cape Fear River: Sampling:

- Turbidity- Salinity- Conductivity- Dissolved Oxygen

Sampling Locations Wetlands

Leachate treatment area:

Sampling:

-Turbidity-Salinity-Conductivity-Dissolved Oxygen

Importance of Sample Testing Dissolved Oxygen (DO)

Dissolved oxygen analysis measures the amount of gaseous oxygen (O2) dissolved in an aqueous solution.

When performing the dissolved oxygen test, only grab samples should be used, and the analysis should be performed immediately, on site.

We measured both the milligrams per liter and the percent of saturation, which indicates the percentage of the total amount of DO the water could hold, at the temperature and composition at the sampling time.

…More on Dissolved Oxygen… Total dissolved gas concentrations in water

should not exceed 110 percent. Concentrations above this level can be harmful to aquatic life.

Adequate dissolved oxygen is necessary for good water quality. Natural stream purification processes require adequate oxygen levels in order to provide for aerobic life forms. As dissolved oxygen levels in water drop below 5.0 mg/L, aquatic life is put under stress. The lower the concentration, the greater the stress. Oxygen levels that remain below 1-2 mg/L for a few hours can result in large fish kills.

Importance of Sample Testing Conductivity

Conductivity (electrical conductivity and specific conductance) measures water's ability to conduct an electric current and is directly related to the total dissolved salts (ions) in the water.

Conductivity, abbreviated EC, is reported in µS/cm (microSiemans per centimeter). EC is temperature sensitive and increases with increasing temperature.

The purity of water for use in the is mainly controlled by its conductivity, the purity of water increases as the conductivity increases.

As a reference, the pharmaceutical standard for pure “water for injection” is 26.6 µS/cm.

Importance of Sample Testing Turbidity

Turbidity is a measure of the TSS (total suspended solids), by measuring the cloudiness.

Turbidity is measured in Nephelometric Turbidity Units (NTU’s). The term Nephelometric refers to the way the instrument

estimates how light is scattered by suspended particulate material in the water.

Turbidity may be composed of organic and/or inorganic constituents. Organic particulates may harbor high concentrations of bacteria, viruses, and protozoans. Thus, turbid conditions may increase the possibility for waterborne disease.  Particulates also provide attachment sites for heavy metals such as cadmium, mercury and lead, and many toxic organic contaminants such as PCBs, PAHs and many pesticides.

As a result, turbidity adds real costs to the treatment of surface water supplies used for drinking water since the turbidity must be virtually eliminated for effective disinfection (usually by chlorine in a variety of forms) to occur.

Biological Oxygen Demand (BOD) The BOD test takes 5 days to complete and is performed using

a dissolved oxygen test kit.  The BOD level is determined by comparing the DO level of a

water sample taken immediately with the DO level of a water sample that has been incubated in a dark location for 5 days. 

The difference between the two DO levels represents the amount of oxygen required for the decomposition of any organic material in the sample and is a good approximation of the BOD level.

This is measured in milligrams per liter or ppm.  

Biological Oxygen Demand (BOD) A BOD level of 1-2 ppm is considered very good.  There will not be

much organic waste present in the water supply. 

A water supply with a BOD level of 3-5 ppm is considered moderately clean.  (post treatment the BOD was 3.07 mg/L)

In water with a BOD level of 6-9 ppm, the water is considered somewhat polluted because there is usually organic matter present and bacteria are decomposing this waste. 

At BOD levels of 100 ppm or greater, the water supply is considered very polluted with organic waste.  

Generally, when BOD levels are high, there is a decline in DO levels.  At high BOD levels, organisms that are more tolerant of lower dissolved oxygen (i.e. leeches and sludge worms) may appear and become numerous.  Organisms that need higher oxygen levels (i.e. caddisfly larvae and mayfly nymphs) will not survive. 

The End