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is of a uniform character for a depth of at least 6 feet. Neither water nor rock has ever been found in excavations of this depth on the property. Outcrops of soft shale rock with strata vertical are, however, of frequent occurrence in different parts of the village. The surface of the ground is bare and slopes away from the school to the northwest with a fall of about 5 feet per 100 feet. There are no wells on or near the school property and the nearest house to the plot on which it is proposed to construct the disposal plant is over 100 feet from the lot line, the intervening ground being used for garden purposes.

The plans as submitted contemplate the construction of a sewage disposal plant comprising a settling tank, dosing chamber, and subsurface irrigation system divided into two sections.

The settling tank is to be of concrete of 4,000 gallons' capacity furnishing an average detention period of 24 hours, assuming a flow of 10 gallons per capita per day. The inlet pipe enters at one end above the water line and the outlet pipe fitted with a band extending below the water level located at the opposite end conducts the effluent into the dosing chamber. A reinforced concrete bafile is provided at the inlet end to prevent unnecessary disturbance of the contents of the tank, and another similar baffle at the outlet end to prevent sludge and floating material from escaping from the tank. Removable slabs are provided in the top of the tank to give access for inspecting and cleaning.

The dosing chamber is of similar construction to the tank and is located immediately adjacent to it, the south wall of the former forming the north wall of the latter. This chamber has a capacity of about 825 gallons. Assuming that the entire flow from the school reaches the plant in 7 hours this capacity is an equivalent of about 12 hours' average flow during the day. The chamber is fitted with a 6-inch automatic siphon designed and arranged to discharge the contents of the chamber through the diverting manhole into the tile of the subsurface irrigation system.

The subsurface irrigation system comprises 1,952 feet of 3-inch agricultural drain tile divided into two sections of approximately equal size. The tile is to be laid in lines 4 feet on centers with open joints, protected by tar paper and each line is to have a uniform fall of 48 inch per foot. The contents in one section of this field is approximately 350 gallons, while as noted above, the discharge from the dosing tank will amount to 825 gallons. Obviously the field will not operate properly under these conditions and either the capacity of the field should be increased by the use of 4-inch tile or the size of the dosing tank decreased so that the cubical content of the tile will be approximately equal to but not less than that of the dosing chamber.

The main distributors are of 6-inch vitrified sewer pipe laid with a fall of 14-inch per foot. A diverting gate is provided so that the flow can be turned into either field at the will of the attendant.

In view of our examination of these plans and after careful consideration of the essential features of the design and of local conditions, I beg to recommend that the plans be approved and a permit issued for the discharge of effluent from the plant by percolation through the soil into the waters of Claverack creek in the village of Philmont on the following conditions:

1. That only sanitary sewage and no storm or surface water from roofs or other areas shall be admitted to the proposed disposal plant.

2. That the cubic content of the subsurface irrigation field shall be increased or the size of the dosing tank decreased so that the content of one section of the field shall be approximately equal to but not less than that of the dosing chamber and that the size of the dosing chamber be such that the discharge will not occur at intervals of less than one hour.

3. That the settling tank shall be cleaned whenever found necessary and that the sludge be disposed of in such a manner and in such a place as to create no nuisance, and under no condition shall such sludge be discharged or deposited in any watercourse or on the surface of the ground in such a place that it might be washed by rain or melting snow into any watercourse.

4. No liquid from the disposal plant or any pipe line connected therewith shall be allowed to flow upon the surface of the ground.

Respectfully submitted,
THEODORE HORTON,

Chief Engineer ALBANY, N. Y., December 1, 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 Education of the village of Philmont to discharge effluent from the sewage disposal plant into the ground waters tributary to Clavarack creek within the municipality of Philmont 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 water of this State.

S. That both the sewer system and the sewage disposal works shown by plans approved this day shall be fully constructed in complete conformity with such plans or approved amendments thereof.

4. That only sanitary or domestic sewage and no storm water or surface water from the streets, roofs or other areas shall be admitted to the sewage disposal plant.

5. That the cubic contents of the subsuface irrigation field be increased by increasing the size of the tile or the capacity of the dosing chamber decreased so that the contents of one section of the subsurface irrigation field shall be approximately equal to but not less than the contents of the dosing chamber.

6. That the capacity of the dosing chamber be of such size that it shall discharge not more frequently than once per hour.

7. That the settling tank shall be cleaned whenever necessary and the sludge disposed of in such a manner and at such a place as to create no nuisance, and that under no condition shall such sludge be deposited or discharged in any watercourse or on the surface of the ground at such a place that it may be washed by rain or melting snow into any watercourse.

8. That no liquid from any portion of the disposal plant or from any pipe connected therewith shall be allowed to flow upon the surface of the ground.

M. NICOLL, JR.,

Deputy State Commissioner of Health December 1, 1917

PITTSFORD (Union Free School) 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 Union Free School in the village of Pittsford, Monroe county, submitted to this Department for approval on May 7, 1917.

These plans provide for the disposal of sewage from the school in a sewage disposal plant consisting of a covered two-compartment settling tank, dosing chamber and two cesspools about 25 feet deep and 6 feet in diameter in the bottom of each of which is to be drilled a hole 6 inches in diameter through rock. Owing to the somewhat unusual method of disposal of the sewage provided for by the plans, an inspection of the local conditions was made by a representative of this Department on May 22, 1917, with a view of determining the practicability of providing some other method of disposal.

This inspection showed that the proposed school under construction was being built on the site of the old school which was destroyed by fire last year, The old school was provided with an incinerator for the disposal of sewage which proved to be insanitary and objectionable. The new school which will have a seating capacity of 500 is located near the center of the developed portion of the village on a plot of ground: less than two acres in area. The soil consists of a heavy almost impervious clayey soil with layers of blue clay to a depth of some 16 feet, entirely unsuitable for the disposal of sewage by means of subsurface irrigation. The rock below is said to be a shaley limestone. No suitable area for the disposal of sewage from the school appeared to be available within 34 mile of the school, and the pipe leading to such site would require crossing the Barge canal and a number of railroad tracks.

The village of Pittsford is provided with a public water supply furnished by the Rochester & Lake Ontario Water Company. There are no wells in the village used for water supply purposes and it was learned that all wells were condemned about 10 years ago when the public water supply was installed. Some of the old abandoned wells are now used for the disposal of sewage. There are no public sewers in the village but practically the entire community is provided with cesspools which overflow into wells drilled into the underlying limestone to depths of from 30 to 90 feet. This method of disposal appears to care for the sewage in the village without giving rise to objectionable conditions in the community. It appears that the wells drilled for the disposal of sewage are sunk into the rock substratum until fissures sufficiently large to carry off the sewage are encountered.

Subsequent to the inspection of the village the designing engineer, who is also the president of the board of education, was advised that the proposed method of disposal of sewage at the school is fraught with many uncertainties both from a practical and a sanitary standpoint, and there is no assurance that cesspools drilled into the rock substratum would not become filled when serving a large school, even though this method of disposal might satisfactorily care for the sewage in the village when only one or two families are involved. It was pointed out that the most satisfactory method of disposal of the sewage from the school would be to convey the sewage either independently or in conjunction with the village to a suitable site for complete treatment near some stream and to discharge the effluent into such stream and that the approval of the present plans could be given only on condition that if the proposed method of disposal did not operate satisfactorily some other means of disposal would have to be provided for.

On July 10, 1917, a conference was held in this office with the designing engineer by appointment, when it was learned that the matter of the disposal of the sewage of the school had been given careful consideration at a recent meeting of the trustees of the school and it was decided that the carrying out of plans for discharging the effluent from the disposal plant into a suitable stream would prove too expensive and that the board desired to try to put the proposed method of disposal provided by the plan. The designing engineer stated that the board realized that a permit issued in connection with the approval of the plans would be temporary and that additional or more complete treatment works might be required later.

The proposed settling tank provided for by the plans now before the Department is to be located on the easterly side of the school building and the sewage from the school is to be conveyed to the tank through a comparatively short length of 6-inch sewer laid with a slope of .5 per cent. The settling tank is to be provided with two compartments so arranged as to permit of operating either or both compartments at one time. Each compartment is to be 24 feet long, 6 feet wide and 8 feet deep, inside dimensions, with a depth below the flow line of 6 feet 4 inches. The tank will provide for a capacity of approximately 13,000 gallons and will give a detention period of about two days with both compartments in operation, assuming à per capita rate of sewage contribution of 10 gallons per day. Each compartment is to be provided with a pipe controlled by a valve leading to one of the cesspools by means of which it is presumably intended to draw off the supernatant liquid from the tank during cleaning.

The plans also provide for a dosing tank with two alternating dosing siphons located adjacent to the settling tank. I am of the opinion that it should not be necessary to provide a dosing tank in connection with the proposed disposal plant, inasmuch as it would be just as well to allow the effluent from the settling tank to flow direct to the cesspool. It would be well also to omit the two pipes referred to above for drawing off the supernatant liquid, inasmuch as if used considerable scum and sludge might be discharged into the cesspool through them and cause it to clog up. The tank which has only a relatively small capacity could be cleaned during the summer vacations by pumping its contents into tank wagons or watertight barrels, by means of which it may be hauled away for disposal. The sludge should not be discharged into any stream or other body of water but should be disposed of by depositing in trenches at sufficient distance from any stream to prevent its pollution and sufficiently far from any building to prevent the creation of any objectionable conditions.

The proposed cesspools into which the effluent from the settling tank to be discharged are to be operated in series. Each cesspool is to be 6 feet in diameter and is to be excavated to a depth of about 25 feet or until rock is reached. A 6-inch hole is to be drilled through the underlying rock in each cesspool. As pointed out in our communication to the designing engineer on June 20, 1917, that although the proposed settling tank if properly constructed and operated will remove the grosser solids in suspension from the sewage, the more finely divided solids and the collodial matter in suspension in the sewage will be carried over into the cesspool and unless the fissures in the rock are large and lead to some outlet they will ultimately become filled up with solids discharged into them from the settling tank. There is no assurance, therefore, that the cesspools will continue to operate satisfactorily. It is important, therefore, that the cesspools be inspected at regular and frequent intervals and that additional cesspools should be constructed or other means for the disposal of sewage provided should it be found that the proposed cesspools become clogged. It is possible that the solids that may accumulate in the cesspools may be blown out by inserting a large fire stream under pressure into the 6-inch drilled holes of the cesspools in case of clogging.

In view of the above, I would recommend that the plans be approved on the following conditions:

1. That the pipes for draining off the supernatant liquid from the settling tank be omitted.

2. That whenever required additional cesspool or some other satisfactory means of caring for the sewage from the school be provided.

Respectfully submitted,
THEODORE HORTON,

Chief Engineer ALBANY, N. Y., July 23, 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 trustees of the Pittsford High School to discharge sewage from the proposed sewage disposal works for the school into the waters of the State tributary to Irondequoit bay, within the municipality of Pittsford, 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 the sewage disposal works shown by the plans approved this day shall be fully constructed in complete conformity with such plans or approved amendments thereof.

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

5. That no sewage sludge from any part of the disposal works shall be discharged into any stream or body of water.

6. That whenever required by the State Commissioner of Health additional works for more complete treatment of the sewage from the school shall be constructed and put in operation in accordance with detailed plans satisfactory to this Department.

7. That this permit may be temporarily suspended if the proposed cesspools shall overflow at any time after being put in use unless the sessions of the school shall be discontinued pending the construction of additional works for sewage disposal.

M. NICOLL, JR.,

Deputy State Commissioner of Health. July 23, 1917

PITTSFORD (General Filtration Co.) HERMANN M. BIGGS, M.D., State Commissioner of Health:

I beg to submit the following report on an examination of plans for sewage disposal of the filtros factory of the General Filtration Co., Inc., in the town of Pittsford, Monroe county, submitted to this Department for approval on August 17, 1917.

The disposal plant is to consist of a settling tank and subsurface irrigation field and is designed to care for sanitary sewage only, that is, from the water closets, urinals and lavatories. It is estimated that a maximum of about 25 men will be employed in the factory.

The settling tank is a single compartment tank with baffles, with inlet and outlet located at opposite corners of the tank. It is to be 16 feet long and 8 feet wide with a depth of 8 feet. The capacity of the tank would therefore be about 5,600 gallons, equal to an average flow of sewage of about 11 days on a basis of 20 gallons per capita from 25 persons.

From the settling tank the clarified sewage will flow into a subsurface irrigation field. The plans show no details nor how much subsurface tiling is to be used.

It is found from an examination of the plans that the settling tank is too large for the amount of sewage that it would receive. The daily flow from the toilet fixtures would not be more than 20 gallons per capita and if a maximum of 50 men are employed in the factory a 1,000-gallon tank would be sufficiently large to care for the sanitary sewage from the building. A settling tank of this size would give the sewage about one day's detention. The inlet instead of being on the corner of the tank, as shown on the plans,

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