AES Maritza East 1 / Bulgaria

Project

Region

Client

Period

Value of order:

Project Description

AES Maritza East 1Drilling, cone penetration testing, test pits, In-situ determination of water permeabilitySoil-mechanical and chemical laboratory tests

Galabovo, Bulgaria

AES Maritza East 1 EOOD

February – September 2006

approx. 700.000 €

Purpose

The European Bank for Reconstruction and Development finances theconstruction of the lignite-fired power plant Maritza East 1, located nearthe town of Galabovo, Bulgaria. The total costs of construction are esti-mated at € 1.2 billion. The ash, slag and gypsum waste will be transpor-ted via an 8-km-long band conveyor to a waste dump with a 120 millioncubic metre capacity. This abandoned open-pit lignite mine has alreadybeen filled with ash waste from the old Maritza East 1 power plant andmine waste from a nearby open-cast lignite mine. The dump deposits arenow up to 30 metres thick, exceeding the top ground surface. AES Ma-ritza East 1 EOOD contracted FUGRO CONSULT GMBH with the soilinvestigation for the construction of the new conveyor system, an ad-ministration building and the investigation of the overfilled waste dump.An additional geotechnical investigation was to be provided for an emer-gency storage pit close to the power plant as well as extensive materialtesting to determine the geotechnical properties of bottom ash, fly ashand gypsum.

Realization

Foundation soil investigation was performed with a combination of drillingwith liner sampling and SPT, test pits and cone penetration testing. Dril-ling and sampling was conducted and documented by engineering andtechnical staff of FUGRO CONSULT GMBH. Cone penetration tests wereexecuted with a CPT crawler of FUGRO CONSULT GMBH. Selected re-presentative samples were tested for their soil-mechanical features in the

Former railroadembankment leading to the waste dump

Liner Sampling

Project Description

laboratories of FUGRO CONSULT GMBH (standard classification testslike sieving, consistency limits etc.) and in the sub-contracted laboratoriesof the Technical Universities of Hamburg and Bremen (CU- UU-, shearand Oedometer tests). The drilling and CPT investigations on the wastedump area were a great challenge due to the very low bearing capacity ofthe existing ash dump and the wet and cold weather. It took great effortand time to bulldoze access tracks of total 6 km and prepare them withgravel in order to make them drivable. During field work the enormousamount of data was collected, presented and governed with handheldcomputers using the software GeODIN® Fieldmanager and in the sub-sequent reporting phase the software GeODIN® 5 was applied. The database which contains the results of the soil-mechanical laboratory testsand the profile of the foundation soil and which is integrated in the soft-ware allows any presentation of the results and CPT interpretations/cor-relations with the collected data. In spite of considerable hindrance to thedrilling work, the client’s high demands could be met thanks to the excel-lent cooperation of all parties involved in the project and a good projectorganisation.

Scope of Work / Overview

· 65 drillings at depths of up to 60 metres with liner sampling, SPTtesting and installation of monitoring wells

· 125 cone penetration tests at depths of up to 40 metres· 15 borehole tests to determine water permeability· 21 test pits to collect samples for environmental and geotechnical

testing· 27 chemical water and soil analyses for the Contamination Baseline

Study· 680 geotechnical classification tests (grain size distribution,

consistency, Proctor density, water contents, specific weight)· 180 triaxial, shear and Oedometer tests· Geotechnical data reports for the conveyor system, the waste dump,

the settling basin and material testing of ash/gypsum/slag.

FUGRO CONSULT GMBHUmwelt – Geotechnik – AnalytikFachbereich GeomonitoringHauptstraße 10304416 Markkleeberg

Tel. 49-341-350176Fax 49-341-3501770e-mail fugro-sachsen@fugro.dewww.fugro.dewww.fugro.com

FUGRO CONSULT GmbH is a member of the Fugro Group, with offices throughout the world

G4-2-19e

Drilling Cores

Bulldozing a track to provide access to the drilling location