Fact Sheet: May 1998, Issue #9
Drake Operations Pause for Kiln Repair
On Wednesday morning, March 31, a routine inspection revealed what appeared to be loosened brick within a small section of the Drake Incinerator's rotary kiln. The 12-foot wide kiln is lined with two layers of brick, called refractory brick. The bricks are cast in arcs to fit the cylindrical shape of the kiln. The outer layer, made of thermal insulating brick, fits between the steel case and the inner bricks. The inner layer is a harder-faced refractory brick. Like a potter's kiln, the refractory brick is heated and radiates heat back to what is in the kiln -- in this case, contaminated soil as it tumbles through the rotating 60-foot long kiln.
In order to keep the curved bricks in place inside the kiln, thin steel shims are driven into the gaps between the bricks to keep them wedged securely. Any wear between the bricks and the shims can cause the bricks to shift and wear even faster.
As the conveyor belt moves the soil into the rotating kiln, two natural gas burners heat the air inside the kiln to between 1600 and 1800 degrees Fahrenheit. The relatively cool, moist soil drops onto the kiln's surface causing a thermal shock. Alternating between hot gases and cool soil eventually wears away the brick. Therefore, the refractory brick in the kiln must be periodically repaired or replaced.
During the March 31 inspection, technicians noticed the wear and assessed the situation. Specialists would be needed to install a cast-in-place refractory lining, however it would take some time to schedule these specialists to come to Lock Haven. Therefore technicians decided to repair the small section of worn brick to allow the incinerator to continue processing soil until specialists arrived.
Because the kiln temperatures were so high, the burners could not be turned off suddenly; they had to be slowly turned down in order to let the system cool. It took 36 hours to bring the temperature down so the kiln faceplate could be unbolted and opened. Technicians then decontaminated the kiln's interior so repair crews could work safely.
Working Thursday and Friday, April 2 and 3, crews removed worn refractory and insulation brick and replaced them with new material. With the brick work complete, the Drake Cleanup Team reheated the incinerator. The first burner was fired up about noon Saturday, April 4 and by late Sunday night, April 5 the incinerator had stabilized at its proper operating temperatures. After running through a series of operational and safety checks, the cleanup team resumed full operations shortly after noon on Monday, April 6.
Between April 6 and 10, with the temporary repair in place, the incinerator safely cleaned approximately 3,700 tons of contaminated soil. On April 10, the Drake Incinerator shut down for a three week maintenance period to install cast-in-place refractory lining and replace the kiln brick.
A technician installs replacement refractory brick inside the incinerator kiln. Within the kiln, contaminated soil is heated to temperatures higher than 900 degrees Fahrenheit to drive contaminants out.
OHM Installs New Scrubber
OHM Remediation Services Corp. recently installed an additional piece of equipment to further reduce the likelihood of processed soil escaping in steam produced during the soil cooling process. Referred to as a scrubber, it draws steam from the treated soil as it exits the incinerator. Although the current system of water fog nozzles and steam containment adequately protects the health and safety of the Lock Haven community, the scrubber will provide an extra measure of protection and reduce the perception that dust is leaving the Drake Site. The new scrubber was installed on April 13.
Steam from the wet ash conveyor passes through the scrubber system which cools the steam to a point where it turns back into water and exits the scrubber system to the site's wastewater treatment plant. A 75-horsepower fan draws up to 10,000 cubic feet of steam per minute through an initial water spray and cyclone. The next step involves moving the steam through a ceramic filter system and another water spray. These two steps are designed to turn the steam back into water and separate any ash that may have been taken up by the steam during the cooling process that takes place on the wet ash conveyor. Any ash that is separated during the scrubbing falls to the bottom of the system as a mixture of water and ash and is considered processed soil. The soil is then moved to the processed soil area and tested for backfill criteria with the soil that normally exits the incinerator.
Steam is drawn in from the wet ash bin (right), cleaned by the scrubber and discharged through the stack (left).
What's That Smell?
Driving through the country on a warm spring day you notice an odor -- what's that smell? As the temperatures rise, odors that may have been unnoticeable during the winter months begin to gain strength in the warmer temperatures. This rise in temperature increases the chance that you will smell more odors during your drive.
Now that spring is here, residents of Lock Haven and the surrounding communities may notice chemical odors coming from the general vicinity of the Drake Site. These odors are a result of the warmer temperatures, the ongoing digging at the site and the cleanup occurring at the AC&C Site, which is across the street from the Drake Site. Cleanup at the AC&C Site recently began and involves treating contaminated water in onsite lagoons. The winds tend to blow across the AC&C lagoons and the stacks at the Drake Site, then over the highway and into Castanea, the closest residential community to the Drake and AC&C Sites.
Some chemicals, like ammonia, have a very low odor threshold. This means that they can be smelled at levels far below what is considered a level of concern. Just because you smell the chemical does not mean that it is harmful.
Offsite Work Marks Visible Milestone at Drake Site
Work crews from the Drake Cleanup Team began excavation work just outside the site in early April, a move that signaled that this former chemical plant property is clearly on the way to being restored as a valuable asset to the Lock Haven community.
With the southern tip of the 10-acre site backfilled with clean soil, crews are grading the reclaimed property to accommodate storm water drainage. Up to now, all precipitation falling on the site was considered contaminated and was collected and processed through the site's waste water treatment plant. Now, drainage from cleaned portions of the property can be handled like storm water drainage elsewhere in Lock Haven.
Work crews installed a sewer drop inlet at the southern end of the site, then connected it into an existing storm sewer system. The crews installed about 134 feet of 12-inch pipe from the new drop inlet on the reclaimed Drake property to the existing line, 68 feet south of the property line. The crews installed a temporary plug in the sewer line, then excavated and dug trenches to depths of about ten feet to install the new pipe and a new manhole.
As the area of clean backfill progresses northward on the Drake Site, more of the property will be graded, mounded and connected into the storm drainage system. Precipitation that falls onto the contaminated zone will continue to be collected separately and processed through the onsite waste water treatment plant.
Workers cut through an old storm sewer line to prepare for installing a new manhole box. The manhole box provides a junction for the new storm drain coming off the reclaimed property at the south end of the Drake Site.
Strict Policy Ensures Site Safety
We've all heard the phrase, "zero tolerance." This phrase has special meaning at the Drake Chemical Superfund Site. OHM's corporate policy states that if an employee working at the site tests positive for alcohol or drug use they are fired -- on the spot. What's interesting about the policy at the Drake Site is that the blood-alcohol level used for testing is less than one-half of Pennsylvania's legal limit for drivers, which is 0.1. If the blood-alcohol level of an OHM employee is .04, that employee will be fired.
Testing for drugs and alcohol is performed on a random basis. The strict drug and alcohol policy enforced at the Drake Site is part of a comprehensive program by OHM to ensure the safety of the community, the employees onsite and the overall cleanup process.
Partner Feature: U.S. Army Corps of Engineers
The U.S. Army Corps of Engineers (USACE) is a branch of the U.S. Army's Office of the Chief of Engineers, headquartered in Washington, DC. USACE is the largest engineering organization in the world. It is made up of 53 regional offices and four engineering research laboratories staffed mostly with civilian employees.
USACE's primary mission is designing and constructing military projects for the Army, Air Force, Army National Guard and Reserve and other Department of Defense agencies. These projects include constructing maintenance and training facilities, aircraft facilities, military housing, medical facilities, recreation centers and commissaries. In addition, USACE supports civil works projects involving environmental restoration, navigation, flood control, water supply, water quality and emergency responses to natural disasters. USACE works closely with communities to develop projects to restore and protect our water and land.
USACE also manages the cleanup of hazardous waste sites and develops innovative cleanup methods. USACE provides scientific and engineering expertise, and quality control and contract management support for the U.S. Environmental Protection Agency (EPA) and other federal, state and local agencies.
USACE and EPA have an interagency agreement, on the national and regional levels, for USACE to help with contract management duties for some of the largest Superfund projects. In the early 1980s, after listing the Drake Site on the National Priorities List, EPA contacted USACE for assistance in managing the contract for the site cleanup. EPA and USACE complement each other's areas of expertise: USACE provides contract management and engineering expertise; EPA provides environmental and regulatory expertise.
USACE's role at the Drake Site is to provide 24-hour-a-day quality assurance of OHM, the contractor operating the incinerator, to ensure that their activities follow the contract guidelines. For example, when OHM conducts sampling activities, USACE representatives conduct their own random sampling and analysis to ensure that OHM's quality control measures are in place and working properly. OHM submits their work plans and reports, such as the Health and Safety Plan, to USACE for review and approval. In addition to providing oversight of the incinerator operations, USACE is also responsible for other everyday tasks at the site, such as processing contract modifications, property administration, processing payment requests and ensuring compliance with federal regulations.
We're Here to Talk to You!
If you are interested in having someone from the Drake Cleanup Team talk to your group, please contact George Drumbor at the Drake Community Outreach Center, at 748-0872.
Next Month: Look for the winners of the Drake Poster Contest!
U.S. EPA Region III
1650 Arch St.
Philadelphia, PA 19103-2029
Gregg Crystall (3HS22)
Drake Team Leader
David Polish (3HS43)
Community Involvement Coordinator
COMMUNITY OUTREACH CENTER
184 Myrtle Street
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