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of earth and other material. The basin is provided with a wooden cover of 2-inch plank. A 6-inch cast iron pipe line conducts the water from the basin to the storage reservoir.

This reservoir is located about 50 feet south of the springs, and has a capacity of 25,000 gallons. It is entirely of concrete and is covered with a very heavy, fiat, reinforced concrete roof. The 6-inch supply line enters bear the top of the north end and the 4-inch outlet pipe to the hospital is connected through the south end wall a few inches above the floor. An 8-inch blow-off line is connected through the floor near the 4-inch outlet. All of these lines are fitted with shut-off valves housed in concrete manholes just outside of the reservoir. A 20-inch square manhole is provided in the roof near the outlet end and steps were shown on the wall below the manhole to provide means of access to the tank. An overflow opening 12 inches by 8 inches is shown under the roof at the south end of the tank to take care of the surplus water. This overflow or spillway discharges on a small concrete apron located on the ground below it. It would seem that this overflow could be located with advantage on the west side of the tank which is nearer the creek. A still better arrangement would be to provide a stand-pipe overflow inside the tank connected to the 8-inch blow-off line to the brook at a point below the shut-off valve. By this means the unscreened opening in the side of the tank could be avoided. No ventilation is provided for the reservoir, and although closed tanks sometimes prove satisfactory it would seem advisable to provide some means for maintaining a circulation of air over the water in the tank. Ventilation could readily be provided by openings through the roof of the tank. Such openings should be arranged to exclude surface water, and should be screened to prevent the entrance of birds and insects.

A 4-inch cast iron pipe line conducts the water from the reservoir to the hospital. Two double hydrants with 24/2-inch outlets are located at the lower end of the line, one hydrant being placed on each side of the building.

Sewage disposal According to the plans it is proposed to dispose of the sewage from the hospital by sedimentation and subsurface irrigation. The disposal plant is located about 200 feet south of the hospital buildings.

A 6-inch cast-iron pipe conducts the sewage from the building to the settling tank of the disposal works. The grade of this pipe is not given, but it is apparently quite steep; and precautions should be taken in constructing the line to make the rate of fall in the 25 feet next to the tanks not greater than 1/4 inch per foot. The settling tank is of concrete, covered, and has a capacity of 1,800 gallons, giving an average detention period of a little over 8 hours with an assumed sewage flow of 100 gallons per capita per day. At the lower end of the tank and integral with it is a dosing chamber fitted with a 5-inch siphon. The capacity of this chamber is 225 gallons, the equivalent of about one hour's average flow. The siphon or dosing chamber discharges into the distributing tank.

This tank is an open concrete basin 3 feet by 5 feet with a stepped floor apparently intended to aerate the effluent from the settling tank. In view of the fact that this chamber is open and located in front of and close to the hospital, particular care should be taken to form and slope the floor so that no sewage will be left exposed to the atmosphere between doses. Two valves are provided at the lower end of this basin by means of which the sewage may be turned into either of the 2 sections of the subsurface irrigation field at the will of the attendant.

Two thousand feet of 4-inch agricultural drain tile laid 18 inches below the surface and divided into 2 sections of equal size are provided to receive the flow from the distributing tank. Each section of the subsurface irrigation field comprises 5 lines of tile 200 feet long laid approximately 4 feet on centers. The tile is laid with open joints, embedded in gravel and the joints protected with tar paper. Assuming a population of 50 people, this gives a

length of 40 feet per capita, a figure considerably smaller than can be recoinmended for the kind of soil reported as occurring in this location. It would seem advisable with the shalý gravel encountered here to provide at least 60 feet of drain tile for each person living at the hospital.

A sludge bed is provided for drying the sludge from the settling tank. This bed has an area of 250 square feet which appears to be ample for the size of the tank. The bed is 12 inches thick built up of layers of stone and gravel graded from 2-inch stone at the bottom to 1/16-inch gravel at the top. The inlet pipe discharges on a concrete apron about 4 feet square at the upper end of the bed. Six-inch tile drains laid on the bottom collect the effluent and discharge it into 150 feet of subsurface tile laid in the same manner as the tile of the main disposal field. As shown on the plans the pipe connecting the settling tank to the sludge bed is of 6-inch tile laid on a 0.5 per cent grade. On account of the small size and flat grade of this line it is probable that considerable trouble will be experienced in its use due to stoppages; and it would seem advisable to use 8-inch pipe in place of the 6-inch, and to give the line a grade of not less than 2 per cent; and, if possible, of 3 per cent. The valve in the tank at the upper end of this line should be set lower than now shown on the plans so that the bottom of the settling tank will readily drain into the pipe.

In view of the results of our examination of these plans, and after a careful consideration of the essential features of the design and of local conditions, I would recommend that the plans for a water supply for the Otsego County Tuberculosis Hospital be approved with the following conditions:

1. That the overflow from the reservoir be arranged so that the waste water will not cut away the ground near the foundation of the settling tank.

2. That all openings of the reservoir be screened.

3. That suitable ventilation be provided for the reservoir. I would further recommend that the plans for sewage disposal for the Otsego County Tuberculosis Hospital be approved and a permit issued for the discharge of the effluent of the sewage treatment plant into the tributaries of Otsego creek with the conditions:

1. That sufficient tile be provided in the subsurface irrigation fields of the sewage disposal plant to give a length of not less than 60 feet per capita.

2. That the sludge outlet from the settling tank be set at such an elevation that the floor of the tank will readily drain into it.

3. That the size of the sludge pipe be increased to 8 inches and, if possible, the pipe be laid on a grade of not less than 2 per cent.

4. That the floor of the distributing tank be so formed and sloped that it will drain completely between each dose; and that if required at any time by the State Commissioner of Health the distributing tank shall be fitted with a suitable cover.

Respectfully submitted,
THEODORE HORTON,

Chief Engineer ALBANY, N. Y., October 19, 1917

PERMIT Application having been duly made to the State Commissioner of Health, as provided by section 76 of chapter 49 of the Laws of 1909, the “ Public Health Law," as amended by chapter 553 of the Laws of 1911, constituting chapter 45 of the Consolidated Laws, permission is hereby given to the board of supervisors of Otsego county to discharge effluent from the proposed sewage disposal plant for the Otsego County Tuberculosis Hospital into the waters of the State tributary to Otsego creek within the town of Laurens in accordance with the plans accompanying the petition, under the following conditions:

1. That this permit shall be revocable at any time or subject to modification or change when in the judgment of the State Commissioner of Jealth such revocation, modification or change shall become necessary.

2. That the issuance of this permit shall not be deemed to affect in any way action by this Department on any future application that may be made for permission to discharge additional sewage or effluent into the waters of this State.

3. That the sewers and sewage disposal works shown by plans approved this day shall be fully constructed in complete conformity with such plans or approved amendments thereof except as provided in Conditions 5, 6 and 7 of this permit.

4. That only sanitary or domestic sewage and no surface or storm water from grounds, roofs or other areas shall be discharged into the sewage disposal plant.

5. That sufficient tiling shall be provided in the subsurface irrig:itio fields of the sewage disposal plant to give a length of not less than 60 feet per capita.

6. That the sludge outlet from the settling tank shall be set at such an elevation that the floor of the tank will readily drain into it; that t! size of the sludge pipe shall be increased to 8 inches; that the sludge pipe, if possible, shall have a gradient of not less than 2 per cent.

7. That the floor of the distributing tank shall be so formed and sloped that it will drain completely between each dose; and that if required at any time by the State Commissioner of Health the distributing tank shall be fitted with a suitable cover.

M. NICOLL, JR.,

Deputy State Commissioner of Health October 22, 1917

OVID (Coleman House)

HERMANN M. BIGGS, M.D., State Commissioner of Health:

I beg to submit the following report on our examination of plans for sewage disposal for the Coleman House at Kidders in the town of Ovid, Seneca county, submitted to this Department for approval on April 5, 1917.

According to the data submitted with the plans this hotel which is located on the westerly shore of Cayuga lake, is occupied during the summer months only at which time it accommodates from 50 to 60 people per day. The total population to be served including servants and employees will be somewhat greater. The water supply for drinking purposes is obtained from springs located on a hillside west of the hotel. The water supply for the toilets and baths is pumped from the lake and is said to amount to about 1,100 gallons per day. The soil on the property is claimed to be a heavy red clay to a depth of 4 or 5 feet.

Plans for a sewage disposal plant for this hotel consisting of a settling tank, dosing tank and subsurface irrigation system were first submitted for approval on January 6, 1917. After our careful examination of the plans they were returned without approval to the designing engineer who was advised that in all probability a subsurface irrigation system would not operate satisfactorily in a heavy clay soil and that some other site where the soil is more suitable should be selected or that some other means of disposal of the sewage should be provided. The engineer was also advised that the approval of plans for the treatment of the sewage of the hotel on open or covered sand filters or in sprinkling filters or contact beds with the sterilization of the effluent from the coarse grained filters would be considered.

The plans now submitted show that it is proposed to treat the sewage from the hotel in a sewage disposal plant consisting of a settling tank, dosing tank and open sand filter. It is suggested in the report of the designing engineer that a light removable cover might be provided for the filter or that the filter bed might be sprinkled with chloride of lime or that a liquid mixture of chloride of lime be applied to the siphon chamber of the plant in

der to prevent the creation of objectionable odors. A removable cover would in all probability prove satisfactory for this purpose and although there would be no objection to applying a solution of chloride of lime to the dosing tank, chloride of lime should not be sprinkled on the surface of the filter inasmuch as this would tend to clog up the bed and require more frequent cleaning. If a solution of chloride of lime is used it should be applied at a uniform rate.

The settling tank forming the preliminary portion of the plant is to be covered and is to be 11 feet long, 5 feet 3 inches wide and 5 feet deep inside dimensions with a depth of flow of 4 feet. It will have a capacity of about 1.700 gallons and will, therefore, give a detention period of nearly 112 days with a flow of 100 gallons per day.

The dosing tank which is to be located adjacent to the settling tank is to be provided with an automatic discharge siphon by means of which the effluent from the settling tank will be discharged intermittently to the distributing system of the sand filter. Although the size of the siphon is not given it appears from scale dimensions to be a 3-inch siphon. The average rate of discharge of 3-inch siphons having a draft of 13 inches as proposed is considerably less than 1 cubic foot per second. For a sand filter having as large an area as the proposed filter a siphon having an average rate of discharge of not less than 1 cubic foot per second should be provided in order to insure a satisfactory distribution of the sewage over the surface of the filter bed. This would require a 5-inch or 6-inch siphon depending upon the draft.

The proposed sand filter is to be 26 feet square and is to be filled to a depth of 3 feet with sand having an effective size of from .2 to .4 mm. It is to be provided with 2 lines of underdrains which are to be surrounded with gravel. The joints of the underdrains are to be covered with tar paper. The effluent from the filter is to be discharged into Cayuga lake. The proposed filter as designed has an area of .015 acres.

Based upon the reported flow of 1,700 gallons per day, the rate of operation of the filter would be about 70,000 gallons per acre per day. Although the design of settling tanks is generally based on the actual or estimated flow of sewage, the design of sand filters is governed largely by the organic content of the sewage which is practically the same in the case of sanitary sewage, whether the daily per capita rate of sewage contribution is 20 gallons per day as in this case or 200 gallons per day as in the case of very dilute sewage.

It has been found in practice that open sand filters in use all the year round when treating settled sewage cannot be operated satisfactorily and successfully, except perhaps under expert supervision, at rates of more than 100,000 gallons per acre per day, based on a per capita rate of sewage contribution of 100 gallons per day. It is probable, however, that in the case of the proposed plant which is to be operated only during the summer, the sand filter could be operated at twice the above rate or at a rate of 200,000 gallons per acre per day. This would require an area twice as large as that proposed by the plans in order to care for a population of 60 persons. It would be better, however, to install 2 filters so arranged that either of the 2 filters may be temporarily thrown out of use for resting and cleaning than to increase the size of the proposed filter.

From our careful examination of the plans it is found that the proposed sewage disposal plant has in general been designed to meet the local requirements for sewage disposal. Certain modifications should, however, be made in the plant before it is constructed as indicated above.

I would, therefore, recommend that the plans be approved and a permit be issued allowing the discharge of effluent from the proposed sewage disposal

plant into Cayuga lake in the town of Ovid, Seneca county on the following conditions:

1. That an automatic discharge siphon having an average rate of discharge of not less than 1 cubic foot per second be provided.

2. That an additional filter having an area equal to that of the proposed filter be provided and that these filters beso arranged that either of the two filters may be thrown out of use for resting and cleaning.

Respectfully submitted,
THEODORE HORTON,

Chief Engineer ALBANY, N. Y., April 17, 1917

PERMIT Application having been duly made to the State Commissioner of Health, as provided by section 76 of chapter 49 of the Laws of 1909, the “Public Health Law," as amended by chapter 553 of the Laws of 1911, constituting chapter 45 of the Consolidated Laws, permission is hereby given to S. A. Coleman to discharge effluent from the proposed sewage disposal works to treat the sewage of the Coleman House, Kidders, N. Y., into the waters of Cayuga lake near said Coleman House within the town of Ovid in accordance with the plans accompanying the petition, under the following conditions:

1. That this permit shall be revocable at any time or subject to modification or change when in the judgment of the State Commissioner of Health such revocation, modification or change shall become necessary.

2. That the issuance of this permit shall not be deemed to affect in any way action by this Department on any future application that may be made for permission to discharge additional sewage or effluent into the waters of this State.

3. That only sanitary sewage and no storm or surface water from grounds, roofs or other areas shall be discharged into the proposed sewage disposal works.

4. That two sand filter units instead of the one shown by the plans shall be constructed, the combined area of these units to be twice the area of the sand filter shown by the plans.

5. That the dosing siphun shall be of such capacity as to provide for an average discharge of not less than 1 cubic foot per second.

M. NICOLL, JR.,

Acting Deputy State Commissioner of Health April 17, 1917

PHILMONT (School) HERMANN M. BIGGS, M.D., State Commissioner of Health:

I beg to submit the following report on our examination of plans for the disposal of sewage from the Philmont school house at Philmont, Columbia county, N. Y., submitted to this Department for approval by the architect on December 1, 1917.

The school building has a seating capacity of 398 and is located on the north side of Main street near the center of the village of Philmont. The property owned by the village and used in connection with the school has a 150 foot frontage on the street and extends from the street to a line parallel to the street about 130 feet in the rear of the school building. It is proposed to locate the sewage disposal plant for the school on the rear portion of this lot. The ground at the site of the disposal plant is a disintegrated shale of a porous nature. Test pits dug on the school property indicate that the soil

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