Attachment 3 - Technical Exhibit 1.pdf

Waste Water Treatment Plant Operation Services at Sector Field Office Eastern Shore

70Z08420QAA554400

Attachment 3 – Technical Exhibit 1

A. Summary of Operator's Responsibilities

1. Routine Operation Control

a. Visually check performance

(1) Is the effluent clear and free of odor?

(2) Is the color of the activated sludge the normal shade of brown typical of good treatment results for the plant?

b. Inspect the mechanical equipment (see maintenance instructions of the manufacturer provided in

Appendix F)

(1) Are blowers operating without overheating or unusual noise?

(2) Is oil level in blower gear case proper?

c. Lubricate mechanical equipment in accordance with maintenance instruction of the manufacturer.

d. Clean up plant.

(1) Scrape walls and hoppers of clarifier chamber.

(2) Clean inlet bar screen and remove very large solids. The large solids removed will hold in a separate container for lime stabilization and drying. Then the solids will be disposed of as a solid waste.

(3) Once a week, brush heavy algae growths from effluent trough and brush or flush solids from clarifier side walls at water line.

(a) Visually inspect surge/pump station to empty trash basket in the unit. Also check to see if pumps are operating properly.

e. Measure D.O. of aeration tank liquor. If D.0. is less than 1.0 mg/ L or sludge is turning a dark color and producing a detectable septic odor, increase air supply.

f. Conduct a settle-ability test on a sample collected near the outlet end of the aeration chamber. If the sludge are more than 75% at the end of 30 minutes, waste sludge to the sludge holding tank. The need to waste sludge may be confirmed by high sludge blanket level in the clarifier chamber. For best results, shut off air supply in sludge tank for 30 minutes prior to operating waste sludge air lift.

g. Make entries in plant operating and maintenance logs, as required.

2. Non-Routine Plant Operations Duties

a. Check overflow from sludge tank when waste sludge air lift is in operation. When reasonable low solids in the overflow cannot be maintained, remove digested sludge from the sludge tank.

b. Change oil in the blower gear case every 1500 hours or two (2) months of operation.

c. Clean blower intake filters in accordance with manufacturer’s instruction.

d. Inspect plant for damage to protective coating and touch up damaged areas before extensive rusting creates a major painting problem.

e. Operate all valves and other non-regularly used equipment to be sure they are in good working condition.

f. Maintain plant site so that it presents an attractive appearance.

REMEMBER: A clean, properly cared for plant means fewer repairs, less maintenance and more efficient operation.

B. Routine Operation

The operation of the plant is a matter of observing the effluent for any deterioration of quality , regular inspection and lubrication of the mechanical equipment , clean-up or housekeeping work, and performance of tests to control the air supply and the solids concentration. Other operational requirements include periodic maintenance of buildings and grounds and periodic removal of sludge from the "sludge holding tank" for final disposal by a contracted septic tank service.

The operator's first action on arrival at the treatment plant is to make a quick visual survey of the plant. The plant effluent discharging over the weir of the settling tank effluent trough should be relatively clear, free of solids and completely free of odor. All motors and mechanical devices should be operating in a normal manner and the distribution of air in the aeration chamber should be uniform. Where indications of abnormal conditions are found, such corrective action should be undertaken promptly. When operation appears to be normal, the operator should then proceed with routine inspection and lubrication of mechanical devices in accordance with the equipment manufacturer's maintenance instructions. He should follow this with performance of the test required to check the air supply and the solids concentration in the purification system. Effluent quality tests and the housekeeping jobs should be done to complete the routine operating duties. In addition to a record of test results, a log of plant operation providing a written record of all repairs, adjustment, lubrications, and unusual operation conditions is strongly recommended.

C. Operational Tests

Results of chemical, biological and physical tests are utilized to determine the operating needs of the plant.

These tests are discussed in the USCG Chincoteague Station Wastewater Treatment Facility Operations and

Maintenance Manual.

D. Interpretation of Test Results

The interpretation of the results of the test at the various locations are described in the following paragraphs:

Plant Performance Tests: The biochemical oxygen demand (BODs), Total Kjeldahl Nitrogen (TKN) and Total Suspended Solids (TSS) tests performed on the effluent from the plant are parameters used for determining the strength of the wastewater leaving the plant. By keeping records of effluent characteristics, the plant personnel will be able to determine if there are any significant changes in the ability of the plant to maintain treatment of the waste. In order to correlate these parameters it is important that when performing these tests, the test be conducted on the same composite sample.

Those tests performed on the influent and effluent can also be used to determine the plant efficiency in terms of the percent removal of each constituent. Using the Carbonaceous Biochemical Oxygen

Demand (CBOD) for an example, the removal efficiency is calculated as follows:

% CBOD removal = CBOD (infl.) - CBOD (effl.) x 100

CBOD (infl.)

Thus, if the influent sewage had a CBOD of 240 mg/1 and the effluent CBOD was 24 mg/1, the removal efficiency would be:

240-24 x 100 = 90% CBOD Removal

The same basic formula is used for determining the removal efficiency of each of the other parameters. If the raw sewage influent begins to show signs of an increase in strength, the plant personnel should vary the process controls to account for the change. Any decline in the removal efficiency should alert the operator to make an effort to find the cause of the decline and make the appropriate process changes. Efforts should be made to adjust the system to the highest possible removal efficiency.

The pH will indicate if any drastic changes in the acid or base characteristics have occurred which will either upset the treatment process or have a detrimental effect on the receiving waters. Normally, the pH of the influent and effluent should remain relatively constant and be in a range of 6.0 to 9.0. If the pH is outside the normal range, the source of the abnormal discharge should be located and the detrimental flow stopped.

The dissolved oxygen (D.O.) content of the influent will measure the degree of septicity of the influent wastewater. If the D.O. is low or equal to zero, hydrogen sulfide gas can be expected and the need for odor control will be evident. The effluent D.O. should be kept as high as possible.

The total plant performance tests measure the efficiency of the entire plant, which is what the state agencies are primarily interested in. However, it is also important to determine if each of the treatment units utilized in the treatment plant are operating at their best efficiency.

Therefore, the discharge from each plant unit should be tested for BOD, TSS, TKN, pH, DO, and residual chlorine to determine how well the system is operating by comparing the effluent tests results with results obtained on the influent tests.

Preliminary Treatment Test

Once each month the personnel should test the waste discharged by the bar screen for total volatile suspended solids. If the level is too high, the aeration to the basins may need to be increased slightly to keep organic material in suspension in the chamber.

Secondary Treatment Test

The main control parameter for operation of the aeration basins is dissolved oxygen. The D.O. must be maintained above 1.0 mg/I in the aeration basins at all to times maintain aerobic conditions.

Generally, the pH of the effluent should be in the 6.0 to 9.0 range.

Clarification

The effluent of the clarifier should be tested periodically for settle-able solids determination. After 30 minutes of settling in the settle-able solids test, an efficiently operating clarifier should show a slight dusting of sludge settling with some light suspended floe in the liquid above. If the liquid above the settled sludge is cloudy, it is an indication of poor performance of the final settling process. Other solids and BOD5 testing should be performed on samples of the clarifier periodically as a means for monitoring the efficiency of the settling process.