Fact Sheet: September 1998, Issue #13
Drake Cleanup Reaches New Milestones
Progress has been steady throughout the summer at the Drake Chemical Superfund Site allowing the Drake Cleanup Team to reach the following milestones:
- On August 2, as production resumed after a shut down for planned maintenance, the Team reached the 35% complete mark.
- On August 6, the Team passed another milestone: 100,000 tons of material was cleaned, tested and backfilled onto the property.
- As of August 25, 40% of the soils and rock from the site had been cleaned.
- Since returning to full operation on May 6, following refractory replacement, the incinerator has operated at 108% of its productivity target.
- To date, nearly 65% of the total contaminated soil on site has been excavated and either processed or stockpiled for processing.
Production resumed the first weekend in August after a planned cold shutdown during the last week of July. That maintenance period included the replacement of a set of feed screws as well as a series of repairs and calibrations that necessitated cooling the plant down. This was the first cold shutdown since kiln refractory was replaced in April, and it gave the Team an opportunity to confirm that the new refractory was performing well. (See the May 1998 issue of the Drake Update for an article describing the kiln refractory replacement.) The system reached proper operating temperatures and feed of contaminated soil began on the morning of August 2. Production continued for the next several weeks. By August 17 nearly 5% of site soil had been processed, and analysis of throughput productivity suggested that the feed screws were wearing. Plans were immediately begun for a change of feed screws. Feed screws deliver as much as 1,000 tons of contaminated soil into the hot kiln each day.
The Team completed screw replacement on August 19th and 20th. Since the screws could be replaced without cooling down the plant, the maintenance interrupted the soil feed for only about 42 hours. As is normal for the Team during production pauses, a series of additional maintenance projects, calibrations and testing was completed during the short break.
Although the facility continues to exceed its productivity targets, the Team is reviewing feed screw engineering with an eye to achieving the ideal service life for these key parts. This is being done to improve the project schedule while assuring that the incinerator is operated safely for the benefit of the workers and the Lock Haven community.
pair of new feed screws has been attached to the feed hopper and is awaiting
reinstallation of the cooling water jacket before the assembly is reinserted
into the kiln. The end of the screws will be set at the mouth of the kiln,
just below the gas burners where the screws deliver soil into the kiln
Drake Treats 15,250,000 Gallons of Water
How much water is 15,250,000 gallons? That much water could fill the Lock Haven High School gymnasium 16 stories deep. Or, if that much water were poured into the new Wal-Mart Superstore, nearing completion on Hogan Boulevard, the water would be 12 feet deep. No matter how you look at it, that's a lot of water.
Since work began at the Drake Chemical Superfund Site in May 1995, the Drake Cleanup Team has captured 15,250,000 gallons of rainwater and other process water that has come in contact with contaminated soil on the Site. The Team has tested and treated all of this water for discharge into Bald Eagle Creek through the local storm drainage system.
The Team recognized that rainwater falling on the property, or other water used in the cleanup process, could pick up contaminants from the soil. For this reason, the first onsite building erected to prepare for the cleanup was a wastewater treatment plant (WWTP). Following completion of the risk and trial burns in early 1997, the Team erected a new WWTP building on clean soil. By moving to the new building, water treatment could continue while contaminated soil under the original building is removed for treatment. Operations were moved into the new building in October 1997, and will continue from there until the project is complete.
The Team built the WWTP to ensure that no contamination washed off the property while the cleanup project is underway. Using proven and accepted technology to treat water, the WWTP removes metals and volatile and semivolatile organic compounds. The Team ensures proper operation through weekly testing for 13 site-related chemicals.
In March 1995, the Pennsylvania Department of Environmental Protection (PaDEP) issued the Team a National Pollutant Discharge Elimination System (NPDES) permit. The permit allows the Team to operate the WWTP and details the requirements for testing all water discharged into Bald Eagle Creek. (Copies of the NPDES permit are available for public review at the Drake information repositories.)
Within the contamination zone, water accumulates in two ponds linked by a 24-inch pipe. In addition to storm water running off the soil stockpile, water also drains into the ponds from decontamination operations, from sump pumps at several onsite locations and from wash down water used near the incinerator.
While the water accumulates in these outdoor ponds, silt begins to settle out. The water is then pumped into the WWTP where it is held in a series of three 10,000-gallon tanks. Additional settling occurs in these three tanks, along with the first of many treatment processes.
Sulfuric acid is added as the water is pumped into the second of the three tanks. (Sulfuric acid causes barium to form particles that can fall out of the water.) From the settling tanks, water is pumped into a three-chamber reactor tank. In the first chamber, barium particles settle to the bottom. As water spills across a dam into the second chamber, additional compounds are added that help other metals settle out. The principal addition here is caustic soda, which counteracts the acid from the earlier step. In the second chamber, a mixer speeds the process of neutralizing the acidic water, turning it into a base solution. The third chamber also contains a mixer that continues the process of bonding metals into particles that can be removed from the water.
Water flows out of the third chamber into a clarifier. In the clarifier, the bonded metals and other particles settle to the bottom where they form sludge. The sludge is periodically pumped out of the clarifier to a sludge processor that removes the water from it. Dried sludge is put back into the contamination zone for incineration along with the soil.
Water flows out of the clarifier into an equalization tank where the pH or acid/base value is brought back to neutral. From the equalization tank, water passes through a sand filter to remove solids that did not fall to the bottom of the clarifier.
In the next step, the water passes through an air stripper. This unit forces air through tumbling water to collect volatile organic compounds that are dissolved in the water. Air from the stripper then passes through carbon filters to capture the organic compounds.
After passing through the air stripper, the water is held in another equalization tank before being sent through a series of mesh bag filters. These filters remove any fine particles left in the water.
In the last step, called the polishing step, the water is sent through two carbon filters. Each carbon filter tank contains 10,000 pounds of specially formulated filter carbon to remove any remaining organic compounds from the water. This last step ensures that the water meets the strict standards for discharge.
The clean water is then held in a final tank where it can be used for onsite dust control, or it may be discharged to Bald Eagle Creek.
As described in the NPDES permit, water samples must be collected and sent to a laboratory for testing to ensure that discharged water meets NPDES criteria. Once each week, the Team collects four samples that are tested for Beta-naphthylamine, fenac, volatile organic compounds and metals. Periodically, the U.S. Army Corps of Engineers takes separate quality assurance samples to verify that the testing is being handled properly. In addition, PaDEP conducts random checks on the testing quality. Since the WWTP program began, more than 150 sampling procedures have been conducted all have met the NPDES criteria.
Typically, crews of two technicians work ten hours a day, four days a week to operate the WWTP, which can process as much as 4,000 gallons an hour. However, during periods of heavy rain additional technicians support the regular crew so the plant can operate around the clock.
As more of the site is cleaned, less contaminated area contributes to the generation of contaminated waste water, and the work of the WWTP will slowly taper off as the project nears completion.
along with excess process water, collects in sediments ponds within the
contaminated zone. It is pumped, from the inlet at the island at the far
end of the pond, at rates as high as 4,000 gallons an hour into the waste
water treatment building at the far right.
sets of carbon filters (a primary and a backup) comprise the polishing
step the final step in which any remaining organic contamination is removed
from water before it is discharged to Bald Eagle Creek.
Moss Study Finds No Change in Dioxin Levels During Drake Incineration
Charles R. "Dick" Lee (shown at left, with Clinton County Farm
Bureau president David Snook) briefed the Farm Bureau board of directors
on Sept. 1 about the latest analysis of data collected from mosses and
leaves. According to Dr. Lee, "the incineration of soil does not
appear to be adding any measurable quantities of dioxins to the the air
being monitored with moss bags." Dr. Lee, a soil scientist with the
U.S. Army's Waterways Experiment Station in Vicksburg, Miss., has been
conducting this study since October 1995 along with plant pathology scientists
from Pennsylvania State University to determine if soil incineration at
Drake is causing any change to the area environment. (See the January
1998 issue of Drake Update for a description of the study.) The study
will continue throughout the burn.
Drake Superfund on-site soil incineration project is cleaning the contaminated
soil sitting above the water table. For years, contamination from this
soil had been steadily leaching into sub-surface groundwater. Once the
Drake soil is cleaned, a separate project takes over as the lead effort
in protecting the Lock Haven community. The owners of the former American
Color and Chemical (AC&C) plant, in a separate agreement with the
U.S. Environmental Protection Agency, will begin the lengthy process of
pumping and cleaning groundwater in the area surrounding the Drake and
AC&C properties. In early August a team of well drillers began installing
a series of pilot wells, along with testing and monitoring wells, throughout
the affected area. Instrumentation placed in these wells is providing
data for the final pump and treat system design.
U.S. EPA Region 3
1650 Arch Street
Philadelphia, PA 19103
Gregg Crystall (3HS22)
Drake Team Leader
David Polish (3HS43)
Community Involvement Coordinator
COMMUNITY OUTREACH CENTER
184 Myrtle St.
Onsite Outreach Coordinator: George Drumbor
Public Hours (Drop-Ins Invited)
Monday: 10:00 - 12:00 and 3:00 - 5:00
Tuesday: 1:00 - 5:00
Wednesday: 1:00 - 3:00 and 5:00 - 7:00
Thursday: 1:00 - 5:00
Friday: 10:00 - 12:00 and 3:00 - 5:00
Saturdays, 1st & 3rd of each month: 10:00 - 2:00
Additional hours by appointment
Community Information HOTLINE: 748-5602