Planning excavations

If an in situ treatment method is not feasible, a soil excavation and treatment method should be conducted. The soil excavation and treatment method is usually more cost-effective for small sites and shallow contamination. Before excavation, planning is needed regarding the following steps of the treatment, among others ... 

The Waste Isolation Pilot Plant (WIPP) is in an excavated salt cavern in southern New Mexico, twenty-seven miles from Carlsbad. The WIPP site is 2,000 yards underground, and defense waste is being placed. There are plans to place there about 6 million cubic feet of material there containing fewer than five million curies of radio activity. 

A carefully planned network of shafts, drifts, and raises are the requisites of a producing underground mine. The word development stands for the preparation of this network. In normal development one can recognize four different kinds of rock excavation and they are shafts, drifts, raises and inclines. The main aim of provision of a shaft is to provide access to or a connection with underground. This access may be utilized for a variety of purposes hoisting rock and ore, personnel and material transport, ventilation, etc. Most modem shafts... 

Establishing an area of paving will often necessitate the excavation of topsoil. Consider, at the planning stage, how the soil is to be removed and what is to be done with it. Can it be used... 

If required, pump-and-treat groundwater remediation and/ or in situ bioremediation are options, but unlike with soil excavation, it may take years for contaminant concentrations to reach the agreed end point. The postclosure part of the closeout activities plan should contain a well-defined exit strategy for any necessary postclosure remediation, based on a sampling methodology that defines progress and determines when the end point is reached. 

Similarly, cost estimates should include such items as preparation of work plans, permitting, excavation, processing, quality assurance/quality control verification of treatment performance, and reporting of data (D15673U, p. 7). For more specific cost estimates for ex situ thermal desorption techniques, refer to the individual technologies in the RIMS 2000 library/database. 

Excavation Your excavation team should coordinate the plans for a dewatering operation. 

Richland, Washington on March 25 on the environmental assessment it has prepared with respect to the vertical exploratory shaft it is planning to excavate in basalt at Hanford. This hearing was not required. However, the DOE is reaching out to obtain public involvement in all steps it takes in implementing the waste program. 

The Town of Greenwich realized that the costs of cleanup were going to be well beyond the capability of the community to pay. In 2004, the town applied for a US EPA brownfields cleanup grant. In its grant application, the town stated that it is committed to redeveloping the site as a public access and recreational park and that it planned to use the grant to excavate PCB-contaminated soil to depth of 4 ft over an area of approximately one-quarter acre. The town committed to backfilling the excavation with clean material, possibly from a local construction project. 

According to the Slovenian historian Tone Ference,84 the upper extermination area, which is said to have been within the camp area of Treblinka II, covered an area of about 172,000 sq.ft. however, to forestall any objections on this score, we shall base our further considerations on the size of the extermination area indicated by the archival plan, namely about 193,700 sq.ft. This area held not only burial pits and the material dug up in the course of their excavation, but gas chambers and other buildings as well. If one accepts the 875,000 dead mentioned in the Jerusalem Trial of John... 

Fig. 21. Horizontal plan of the rock shelter no. 1 of Uppony. A. side passage with sediments of layers 2-5 B. side chamber with sediments of layers 13 and 14 C. the excavation pit of 1963, which cut into layers 6-12. Hatching indicates the location of the remaining material from layer no. 1.

Fig. 36. Horizontal plan of the rock shelter of Rejtek, and longitudinal section of the excavations (A-B). I-III excavation blocks 1-7 numbering of the strata C and D pilot pits of 1957-1958 E rock ceiling F and G bottom of the hollow and boulders H back wall and boulder J side passage P fix point K trench.

Plans for construction of backfilled areas during mining, and for backfilling of mine excavations when mining is finished, including methods for preventing slides or other instability... 

The LT system was mobilized to the site after preparation of a detailed site specific Work Plan and Health and Safety Plan. An Air Permit was received from the Stanislaus County Air Resources Board. The soil was excavated from a 50 ft. by 50 ft. area. During treatment the treated soil was composited daily and analyzed using a Hanby Environmental Test Kit for petrolevim hydrocarbons. This simple test kit, which provides rapid soil analysis, was used as a means of process control. The processed soil operating temperature and retention time was optimized at 422°F and 22 minutes, respectively. The treated soil samples were collected and analyzed for TPH and BTEX s by an independent third party. The average of the 18 samples collected and analyzed using approved analytical techniques are provided on Table I. The treated soil exceeded the treatment criteria of 100 ppm total petrolevim hydrocarbons and 700 ppb toluene. 

Contractors anticipate infiltration when the excavation is planned to go below groundwater level and generally make provisions for diverting the flow of water before it reaches the excavation or removing it before or after it enters. Water problems during construction, which carry a cost penalty, occur when the provisions to handle groundwater prove ineffective. Water problems can range from nuisance value to actual retardation of the construction schedule to complete shutdown. 

Soil movement induced by underground excavation or by vibration due either to construction procedures or facility operations may also be a possible cause of damage to previously placed structures. This potential was recognized in the planning for a subway near a bridge abutment. 

The types of underground hazards or facihties (such as electrical, gas, and telephone utihties process or steam piping drains and sewer lines spiUed or buried hazardous materials etc.) that might be encountered during excavation. Identifying such hazards with the assistance of site maps and plans, utihty compaities, and knowledgeable employees. De-energizing electrical services in the area to be excavated, particularly those over 50 volts AC or 100 volts DC. 

Procedure for correcting maps or plans if unexpected lines or piping are discovered or are not found at the expected locations, and for adding equipment or piping that is being installed in the excavation. 

Considerable new excavation would have to be made at Drakelow, which was expected to take a year to complete and require the labour of 1,200 men. Costs were estimated at 285,000 to excavate the quaner of a million square feet of tunnels, plus a further 140,000 for external services. The Treasury considered the plan for several months but remained sceptical, maintaining that their own scheme of dispersal to prefabricated factories, cheaply built at government expense on surface sites far from the traditional industrial areas, was the better option. This proposal later collapsed, following acrimonious inter-departmental misunderstandings. 

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