BIO REM^® USA, INC.

"Soil & Water Decontamination Specialists"

ENVIRONMENTAL PRODUCTS & SERVICES

Property Description:

    A multi story motel building is located on the property.  The owner reports the property was once previously known to be retail gasoline service station.  It is further reported that all underground petroleum storage tanks (UST's), dispensers and fuel supply lines have been removes along with over 3400 cubic yards of petroleum-contaminated soil.  The former UST's were located where the concrete covered parking lot for the Inn is now located.  The UST's are reported to have contained gasoline and diesel fuel.  This is also the area defined through site assessment studies as the petroleum contaminated "Area of Concern".

    On the south side of the property and to the west across Rockaway Boulevard are motels.  To the north are industrial and small office buildings.  A residential area is diagonally across the intersection of 154th Street and 137th Avenue, to the north of the rear of the motel.  To the southwest, on the other side of Rockaway Boulevard, is a Shell gasoline station.  A fast food restaurant that was formerly a gasoline service station is to the south on the same side of the street.

    The Shell station is southwest of the property at the intersection of Rockaway Boulevard and North Conduit Avenue.  It has an open spill number 9806763, and a closed spill number 9111240.  The motel directly across Rockaway Boulevard has a spill number in 1998, #9800872, related to a #2 fuel oil tank test failure that is still open.

    The suspicion of an offsite source affecting the subject property is a concern as earlier monitoring wells installed on the property did not find floating product in any well but one (W-6) on one occasion during the July - November 2001 period when they were measured monthly.  At that time, small amounts of free product had been reported in wells W-4 (6/28/02) and W-6 (4/12/02).  Fingerprints of the petroleum product could not make a strong identification.  However, both fingerprints said the product most closely resembled fuel oil rather than gasoline or diesel; and the latest fingerprint result ruled out diesel or gasoline.  Therefore, there may be an offsite source of the fuel oil found sporadically in the wells mentioned above.

    Groundwater levels at the property vary seasonally and in response to diurnal tidal changes.  Depth water ranges from 8 to 11-feet below land surface.  In addition there is a very small groundwater gradient across the property.  As a result, depending on whether the tides are rising or falling, the slope of the water table will vary, possibly 180 degrees.  This makes precise delineation of groundwater flow direction at the property difficult for any one measurement period.  However, the regional gradient is toward Jamaica Bay, generally to the south.

    In addition, as the gradient changes from south to north, petroleum floating on the water table may be able to move toward the property from what appears to be (regionally) down gradient areas.  This would potentially create a mechanism for petroleum to move onsite from a southerly to southwesterly direction.  Spills have occurred in the past from nearby sources in these directions (see earlier discussion about Shell station and motel across Rockaway Boulevard).

Scope of Project:

    Based on discussions with the NYSDEC, the cleanup objective is to reduce the hydrocarbon concentration in groundwater samples taken from a line of wells installed in the side walk along Rockaway Boulevard to a level approved by the NYSDEC, called the "Compliance Wells".  The Compliance Wells are W-8 through W-12, and they represent the limit of contamination in this Program.

    Outside influences may affect the outcome of the remediation of this area.  These include the presence of other off-site spills, the tidal influence on the area (groundwater movement back and forth), rainfall runoff to onsite drainage pools, and other off-site unknown influences.

    The goal of the remediation plan will be to progress toward, (over a 6 to 9-month period of time), an average reduction of BTEX to 100 micrograms per liter (ug/l) and MTBE to 100 ug/l in the Compliance Wells, or to such levels as can be reasonably achieved in the time frame, given the appropriate application of the Bio Rem technology.  The goal will be reached when the average BTEX and MTBE concentration of the 5 Compliance Wells meet or are less than the 100 ug/l mentioned above for each of two consecutive quarters of sampling and analysis of groundwater.  Achieving the reduction as described will constitute completion of the NYSDEC closure requirements.

Technology Selection:

    Several remedial alternatives were considered to meet the objectives.  Site specific factors were taken into consideration to obtain the most effective and cost efficient remedial approach.  The specific considerations were:

1. Extent and levels of petroleum related hydrocarbons
2. Soil Lithology: The soil is permeable, relatively homogeneous sandy silt with a trace of clay mixed with small to large gravel.
3. Depth to water and groundwater flow direction
4. Ease of Implementation: The area in the parking lot and building where remediation will be carried out is very small and confined.  There is also a great deal of vehicular traffic that needs to be considered in the selection of a remediation approach.  In addition, as the building is a motel, it is important that no unnecessary noise be created to disturb guests.
5. Cleanup Time / Effectiveness
6. Demonstrated success on similar projects.

Based on these considerations insitu bioremediation was selected as the remedial technology of choice.

Bioremediation:

    The Bio Rem process using H-10™ product was selected due to demonstrated success with the chemicals of concern in similar areas of New York City.

Description of Technology

1. Site Characterization: The site lithology is sandy silt with a trace of clay soil mixed with small to large gravel.  The smear zone is 3 to 4-feet thick and is found approximately 8 to 12-feet bls.  The water table is found from 8 to 11-feet bls, depending on the season and recharge pattern.  The smear zone is found in an irregular shaped area approximately 40 feet by 60 feet.    Discrete up gradient sources are not immediately evident.  However, there is a possibility that offsite sources could affect the property.  Based on the defined contaminant plume, the amount of Bio Rem H-10™ batched solution necessary to remediate this property is determined to be 20,000 gallons.
2. Application Methodology: Application of the microbial cultures will be made through a remedial irrigation system using 20 four-inch diameter schedule 40 PVC wells.  Each well will have a PVC .002" slot screen.  The annulus between the screen and the borehole will be backfilled with gravel up to 1-ft above the screen.  The remainder of the well will consist of a solid riser pope the annulus of which will be backfilled with bentonite.  Each well will be finished at land surface in a manhole that will be set in concrete at grade.  The wells will be spaced 10 ft. on center to allow the H-10™ applications to migrate across the affected area of concern.  A line of Application Wells will be installed along the sidewalk and property boundary of the Airport Inn to make sure the biodegradation solution and microbes reach those areas.  The well depths and screen lengths will vary and be field selected.
3. Initialization and Propagation: The initialization and propagation (growth) of the H-10™ will be done using a natural water source to initialize and grow the cultures on site.  The H-10™ is then placed into the contaminated area through the remedial irrigation system.  All nutrients are consumed above ground during the mixing process at the time of propagation, and only a 100% natural-occurring bacteria solution is introduced into the subsurface.  Injection of the H-10™ solution will take place over several days until the complete 20,000-gallon amount is placed in the ground.
4. Monitoring and Reporting: After the Bio Rem H-10™ batched solution is placed into the contaminant plume, readings are taken at regular intervals.  Field monitoring equipments such as PID, pH and dissolved oxygen meters as well as groundwater samples will be used to follow the progress of the cleanup.  These readings will be taken from wells set aside for sampling and they will not be used to inject the H-10™.  The Compliance Wells and wells W-1, W-2, W-6 and W-7 have been designated as these monitoring wells, called the Monitoring Wells.  It is estimated that it will take 6-9 months, after the final H-10 product placement, to remediate the property to acceptable concentrations.

The project

Maps

Lab Results